Methods, architectures, apparatuses, and systems for contention condition and layer 1 / layer 2 triggered mobility (LTM) usage

Abstract

A process, method, architecture, apparatus, system, apparatus, and computer program product for Layer 1 / Layer 2 (L1 / 2) triggered mobility (LTM). In an example, a wireless transmit / receive unit (WTRU) may receive information indicating configuration information associated with a quality of an LTM. The WTRU may receive information indicating a measurement event. The WTRU may determine a quality of the first set of LTMs based on measurements of the first set of beams from the first plurality of cells. The WTRU may send a measurement report associated with the measurement event and / or perform conditional reconfiguration based on, for example, (1) satisfying the measurement event using the determined quality of the first LTM set and (2) elapsed time since the last LTM cell handover.

Description

[0001] Cross-reference to related applications This application claims the benefit of U.S. Provisional Patent Application No. 63 / 456,933, filed April 4, 2023, which is incorporated herein by reference. Technical Field

[0002] This disclosure generally relates to the fields of communications, software, and coding, including, for example, methods, architectures, apparatuses, and systems for processes used for mobility and more specifically to LTM. Background Technology

[0003] The Wireless Transmit / Receive Unit (WTRU) can be configured to use LTM. When LTM is configured together with LTM-enabled measurement and measurement reporting mechanisms, it is expected to provide a process for LTM to operate in parallel or coexist with Radio Resource Control (RRC) based measurements and mobility. Summary of the Invention

[0004] In an example embodiment, the WTRU may (e.g., implement a method to) receive information indicating configuration information associated with the quality of the LTM. The WTRU may receive information indicating measurement events. The WTRU may determine the quality of a first LTM set based on measurements of a first beam set from a first plurality of cells. The WTRU may send a measurement report associated with the measurement event and / or perform a conditional reconfiguration based on, for example, (1) the determined quality using the first LTM set satisfies the measurement event and (2) the time elapsed since the last LTM cell handover.

[0005] For example, the WTRU can determine the quality of a second LTM set based on measurements of a second beam set from a second plurality of cells. The determined quality of the first LTM set and the determined quality of the second LTM set (e.g., determined) can be used to satisfy a measurement event. For example, the WTRU can determine the first beam set as a subset of (e.g., first) beams from a first plurality of cells and / or determine the second beam set as a subset of (e.g., second) beams from a second plurality of cells. For example, the WTRU can determine the quality of a serving or target cell outside the first LTM set. The determined quality of the first LTM set and the determined quality of the serving or target cell (e.g., determined) can be used to satisfy a measurement event. For example, the WTRU can perform a final LTM handover before satisfying a measurement event. For example, a measurement report may include information indicating the determined quality of the first LTM set, and / or conditional reconfiguration may include sending information indicating the determined quality of the first LTM set.

[0006] In some representative embodiments, virtual cell quality derivation and / or modified cell quality derivation can be performed. For example, the virtual cell quality of an LTM candidate set can be derived using and / or taking into account beams from different cells with L1 / L2 triggered mobility (LTM) candidate sets.

[0007] In some representative embodiments, the WTRU may be configured with an active LTM set and a target LTM set. Cell quality derivation and / or comparison can be performed as in the availability process, such as deriving L3-filtered cell quality using N L1-filtered beam measurements of the cells. At least one additional triggering condition may (e.g., should) be fulfilled by a number of cells from the target and / or source candidate sets.

[0008] In some representative embodiments, the WTRU can use LTM to hand over from a first serving cell to a second serving cell. During the handover, the WTRU can determine L3 cell quality and evaluate L3 event triggering based on measurements applicable to the first and second serving cells, such as if the first and second serving cells were a single serving cell. For example, even after a cell change, the WTRU can use one or more previous serving cell measurements as if they were current cell measurements to continue evaluating (e.g., current) serving cell quality and measuring event triggering.

[0009] In some representative embodiments, the WTRU may execute procedures that allow Radio Resource Control (RRC) reconfiguration completion signaling to be successfully delivered to a centralized unit (CU) such as a gNB after an L3 handover and / or allow L3 measurement event evaluation to be completed (e.g., when a time-to-trigger is running). For example, the WTRU may be prevented from sending L1 measurement reports and / or performing LTM, which could result in LTM handover triggered by a distributed unit (DU) and loss of L3 signaling, and / or could cause the CU to detect a handover failure or reconfiguration failure. For example, the WTRU may apply (e.g., temporary) constraints to neighbor and / or candidate cell L1 reports by using timers and / or by waiting for RLC acknowledgments of the RRC message (complete) transmission, such as current cell beam reporting remaining enabled to allow scheduling.

[0010] In some representative embodiments, the WTRU may include information indicating the PCell identifier / identity in the uplink (UL) RRC message. For example, the PCell ID may correspond to the PCell at the time an event is triggered (e.g., a measurement event, RRC reconfiguration). In the case of RRC reconfiguration, the RRC reconfiguration completion signaling may include information indicating whether an RRC reconfiguration, an L2-triggered reconfiguration, or both has been performed.

[0011] In some representative embodiments, the WTRU may receive configuration information associated with determining LTM quality. The configuration information may include any of the following: (i) a minimum number of beams and / or cells used to determine LTM quality, (ii) offset and / or scaling information, (iii) associations between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using LTM quality as serving cell quality or as an offset for serving cell quality. The WTRU may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions. The WTRU may perform a first measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. The WTRU 102 may use the first measurement and the configuration information associated with determining LTM quality to determine a first LTM quality. The WTRU may send a report associated with the L1 / L3 measurement event based on the satisfaction of the triggering conditions and the minimum time period since the last LTM cell handover, the report including information indicating the first LTM quality.

[0012] In some representative embodiments, the WTRU may receive configuration information associated with determining the mobility (LTM) quality triggered by a Layer 1 or Layer 2 (L1 / L2) event. For example, the configuration information may include any of the following: (i) a minimum number of beams and / or cells for determining the LTM quality, (ii) offset and / or scaling information, (iii) associations between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the target cell quality or as an offset to the target cell quality. The WTRU may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions. The WTRU may perform a first measurement on one or more beams of the target cell and one or more beams of other cells associated with the target cell. The WTRU may use the first measurement and the configuration information associated with determining the LTM quality to determine a first LTM quality. The WTRU 102 may send a report associated with the L1 / L3 measurement event based on the satisfaction of the triggering conditions and the minimum time period since the last LTM cell handover, the report including information indicating the first LTM quality.

[0013] In some representative embodiments, the WTRU may receive configuration information associated with determining the mobility (LTM) quality triggered by a Layer 1 or Layer 2 (L1 / L2) event. The configuration information may include any of the following: (i) a minimum number of beams and / or cells for determining the LTM quality, (ii) offset and / or scaling information, (iii) associations between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the serving cell quality or as an offset for the serving cell quality. WTRU 102 may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions. The WTRU may perform a first measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. The WTRU may use the first measurement and the configuration information associated with determining the LTM quality to determine a first LTM quality. The WTRU may perform a conditional reconfiguration associated with the L1 / L3 measurement event based on the fulfillment of the triggering conditions and the minimum time period that has elapsed since the last LTM cell handover.

[0014] In some representative embodiments, the WTRU may receive configuration information associated with determining the mobility (LTM) quality triggered by a Layer 1 or Layer 2 (L1 / L2) event. The configuration information may include any of the following: (i) a minimum number of beams and / or cells for determining the LTM quality, (ii) offset and / or scaling information, (iii) associations between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the target cell quality or as an offset to the target cell quality. The WTRU may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions. The WTRU may perform a first measurement on one or more beams of the target cell and one or more beams of other cells associated with the target cell. The WTRU may use the first measurement and the configuration information associated with determining the LTM quality to determine a first LTM quality. The WTRU may perform a conditional reconfiguration associated with the L1 / L3 measurement event based on the fulfillment of triggering conditions and the minimum time period elapsed since the last LTM cell handover.

[0015] In some representative embodiments, the WTRU may receive configuration information associated with an active LTM set and a target LTM set. The WTRU may receive configuration information indicating measurement events associated with trigger conditions for the serving cell and / or neighboring cells. The WTRU may determine the number of cells in the active LTM set and / or the number of cells in the target LTM set based on the time elapsed since the last LTM handover. The WTRU may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. The WTRU may send a measurement report associated with the measurement event based on the fact that the trigger conditions are met using (1) the quality of the serving cell modified by a first offset and / or (2) the quality of the neighboring cells modified by a second offset.

[0016] In some representative embodiments, the WTRU may receive configuration information associated with an active LTM set and a target LTM set. The WTRU may receive configuration information indicating measurement events associated with trigger conditions for the serving cell and / or neighboring cells. The WTRU may determine the number of cells in the active LTM set and / or the number of cells in the target LTM set based on the time elapsed since the last LTM handover. The WTRU may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. The WTRU may perform conditional reconfiguration based on the fact that the quality of the serving cell modified by a first offset and / or the quality of the neighboring cells modified by a second offset meets the trigger conditions.

[0017] In some representative embodiments, the WTRU may receive configuration information associated with determining cell quality using L3 filtering. The WTRU may receive configuration information indicating measurement events associated with a trigger time period (TTT) and an offset. The WTRU may determine that a measurement event is satisfied at the beginning of a first time period based on a first trigger condition using the quality of a first serving cell and the quality of neighboring cells using L3 filtering. The WTRU may receive information indicating a switch from the first serving cell to a second serving cell using Layer 1 / Layer 2 triggered mobility (LTM) at the end of the first time period, where the first time period is shorter than the TTT period. The WTRU may determine that a measurement event is satisfied based on the quality of a second serving cell during a second time period using L3 filtering and the quality of neighboring cells during the second time period based on a second trigger condition, where the second time period is after the first time period, and the sum of the first and second time periods is greater than or equal to the TTT period. Based on the measurement result that the quality of the neighboring cell is greater than that of the second serving cell, plus an offset, the WTRU may send a measurement report including information indicating (i) the first and second serving cells and / or (ii) either the first or second time periods.

[0018] In some representative embodiments, the WTRU may receive an RRC reconfiguration message that includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). The WTRU may send an RRC reconfiguration complete message. The WTRU may receive an LTM switchover command. The WTRU may send information indicating that the LTM switchover command was not executed based on the time elapsed since receiving the RRC reconfiguration message being less than the indicated time period. The WTRU may send an LTM measurement report based on the time elapsed since receiving the RRC reconfiguration message being greater than the indicated time period.

[0019] In some representative embodiments, the WTRU may receive an RRC reconfiguration message including information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). The WTRU may send an RRC reconfiguration complete message. The WTRU may receive an LTM switchover command. The WTRU may send information indicating that the LTM switchover command was not executed based on the time elapsed since the transmission of the RRC reconfiguration complete message being less than the indicated time period. The WTRU may send an LTM measurement report based on the time elapsed since receiving the RRC reconfiguration message being greater than the indicated time period.

[0020] In some representative embodiments, the WTRU may receive an RRC reconfiguration message that includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). The WTRU may send an RRC reconfiguration complete message. The WTRU may receive an LTM switchover command. The WTRU may send information indicating that the LTM switchover command was not executed based on the time elapsed since receiving the RRC reconfiguration message being less than the indicated time period. The WTRU may send an LTM measurement report based on the time elapsed since sending the RRC reconfiguration complete message being greater than the indicated time period.

[0021] In some representative embodiments, the WTRU may receive an RRC reconfiguration message including information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). The WTRU may send an RRC reconfiguration complete message. The WTRU may receive an LTM switchover command. The WTRU may send information indicating that the LTM switchover command was not executed based on the time elapsed since the transmission of the RRC reconfiguration complete message being less than the indicated time period. The WTRU may send an LTM measurement report based on the time elapsed since the transmission of the RRC reconfiguration complete message being greater than the indicated time period.

[0022] In some representative embodiments, the WTRU can receive information indicating the configuration of L3 measurement events and / or reports. The WTRU can receive information indicating LTM configuration. The WTRU can receive information indicating conditions for including primary cell (PCell) information in the L3 measurement report. The WTRU can perform measurements on the serving cell and candidate cells. The WTRU can send L1 / L2 measurement reports based on the measurements, wherein the L1 / L2 measurement reports include information indicating (i) the measurement result of the candidate cell is higher than (ii) the measurement result of the serving cell plus an offset. The WTRU can initiate the transmission of L3 measurement reports based on the triggering of an L3 measurement event after sending L1 / L2 measurement reports. The L3 measurement report may include information indicating the identifier of the WTRU's PCell associated with the triggering of the L3 measurement event. The WTRU can receive LTM cell handover commands. The WTRU can reconfigure to another cell based on the LTM cell handover command. The WTRU can complete the transmission of L3 measurement reports.

[0023] In some representative embodiments, the WTRU may receive an RRC reconfiguration message in the source cell (e.g., from the source cell). The WTRU may apply the RRC reconfiguration information included in the RRC reconfiguration message. The WTRU may send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is attributed to an RRC reconfiguration.

[0024] In some representative embodiments, the WTRU may receive an RRC reconfiguration message in the source cell (e.g., from the source cell). The WTRU may apply the RRC reconfiguration information included in the RRC reconfiguration message. The WTRU may receive an LTM cell handover command. The WTRU may reconfigure to another cell based on the LTM cell handover command. The WTRU may send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is attributed to both RRC reconfiguration and LTM reconfiguration. Attached Figure Description

[0025] A more detailed understanding can be obtained from the following detailed description, which is given by way of example in conjunction with the accompanying drawings. As with the detailed description, the figures in such drawings are illustrative. Therefore, the figures (figures) and the detailed description should not be considered limiting, and other equally valid examples are possible and contemplated. Furthermore, the same reference numerals (“reference numerals”) in the figures indicate the same elements, and wherein: Figure 1A This is a system diagram illustrating an example communication system; Figure 1BIt shows that it can be shown Figure 1A A system diagram of an example wireless transmit / receive unit (WTRU) used within a communication system shown; Figure 1C It shows that it can be shown Figure 1A The system diagram shows an example radio access network (RAN) and an example core network (CN) used within the communication system shown. Figure 1D It shows that it can be shown Figure 1A The system diagram shows another example RAN and another example CN used in the communication system shown; Figure 2 This is a block diagram illustrating an example of a measurement model; Figure 3 This is a system diagram illustrating an example of LTM operation; Figure 4 This is a process diagram illustrating the baseline process of LTM; Figure 5 This is a system diagram illustrating examples of switching within and between CUs; Figure 6 This is a system diagram showing an example of a virtual cell; Figure 7 This is a process diagram illustrating an example process for measuring and reporting virtual cell information; Figure 8 This is a system diagram showing examples of adjacent regions and candidate LTM regions; Figure 9 This is a process diagram illustrating an example process for determining and measuring the active LTM set; Figure 10 This is a system diagram illustrating an example of L3 filtering and measurement evaluation; Figure 11 This is a process diagram illustrating an example procedure for L3 filtering and measurement event evaluation; Figure 12 This is a process diagram illustrating an example procedure for LTM measurement and execution pause after L3 reconfiguration; Figure 13 This is a process diagram illustrating an example procedure for indicating the current PCell identity in a triggered measurement report; and Figure 14 This is a process diagram illustrating an example procedure for RRC reconfiguration; Figure 15 This is a process diagram illustrating a first example LTM process according to certain representative embodiments; Figure 16 This is a process diagram illustrating a second example LTM process according to certain representative embodiments; Figure 17This is a process diagram illustrating a third example LTM process according to certain representative embodiments; Figure 18 This is a process diagram illustrating a fourth example LTM process according to certain representative embodiments; Figure 19 This is a process diagram illustrating a fifth example LTM process according to certain representative embodiments; Figure 20 This is a process diagram illustrating an example procedure for a measurement report that uses the association between the serving cell beam and the beams of other cells; Figure 21 This is a process diagram illustrating an example procedure for a measurement report that uses the correlation between the target cell beam and the beams of other cells; Figure 22 This is a process diagram illustrating an example of a conditional reconfiguration process for using the association of the serving cell's beam with the beams of other cells. Figure 23 This is a process diagram illustrating an example of a conditional reconfiguration process using the association of the target cell beam with the beams of other cells; Figure 24 This is a process diagram illustrating an example procedure for measurement reporting using the active LTM set and the target LTM set; Figure 25 This is a process diagram illustrating an example of a conditional reconfiguration process using an active LTM set and a target LTM set; Figure 26 This is a process diagram illustrating an example procedure for measurement reporting using a trigger time (TTT) period; Figure 27 This is a process diagram illustrating an example procedure for LTM measurement pause and measurement reporting; Figure 28 This is a process diagram illustrating another example of a process for LTM measurement pause and measurement reporting; Figure 29 This is a process diagram illustrating yet another example of a process for LTM measurement pause and measurement reporting; Figure 30 This is a process diagram illustrating yet another example of a process for LTM measurement pause and measurement reporting; Figure 31 This is a process diagram illustrating an example procedure for LTM switching and measurement reporting; Figure 32 This is a process diagram illustrating an example procedure for LTM handover and RRC signaling; and Figure 33 This is a process diagram illustrating another example procedure for LTM handover and RRC signaling. Detailed Implementation

[0026] In the following detailed description, numerous specific details are set forth to provide a thorough understanding of the embodiments and / or examples disclosed herein. However, it should be understood that such embodiments and examples may be practiced without some or all of the specific details set forth herein. In other instances, well-known methods, processes, components, and circuits have not been described in detail so as not to obscure the following description. Furthermore, embodiments and examples not specifically described herein may be practiced in place of or in combination with the embodiments and other examples expressly, implicitly, and / or inherently described, disclosed, or otherwise provided herein (collectively, the “Provided”). Although various embodiments in which apparatuses, systems, devices, etc., and / or any elements thereof perform operations, processes, algorithms, functions, etc., and / or any part thereof are described and / or claimed herein, it should be understood that any embodiment described and / or claimed herein assumes that any apparatus, system, device, etc., and / or any element thereof is configured to perform any operation, process, algorithm, function, etc., and / or any part thereof.

[0027] Example Communication System The methods, apparatus, and systems provided herein are well-suited for communications involving both wired and wireless networks. Regarding... Figure 1A-1D An overview of various types of wireless devices and infrastructures is provided, wherein various elements of the network can utilize, perform, and be arranged and / or adapted and / or configured to be used in accordance with the methods, apparatus and systems provided herein.

[0028] Figure 1A This is a system diagram illustrating an example communication system 100 in which one or more of the disclosed embodiments may be implemented. The communication system 100 may be a multiple access system providing content such as voice, data, video, messaging, broadcasting, etc., to multiple wireless users. The communication system 100 enables multiple wireless users to access such content by sharing system resources, including wireless bandwidth. For example, the communication system 100 may employ one or more channel access methods, such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal FDMA (OFDMA), Single Carrier FDMA (SC-FDMA), Zero-Tail (ZT) Unique Word (UW) Discrete Fourier Transform (DFT) Spread Spectrum OFDM (ZT UW DTS-s OFDM), Unique Word OFDM (UW-OFDM), Resource Block Filtered OFDM, Filter Bank Multicarrier (FBMC), and the like.

[0029] like Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, radio access networks (RANs) 104 / 113, core networks (CNs) 106 / 115, public switched telephone networks (PSTNs) 108, the Internet 110, and other networks 112. However, it will be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. As examples, WTRUs 102a, 102b, 102c, and 102d, any one of which may be referred to as a “station” and / or “STA”, may be configured to transmit and / or receive wireless signals and may include (or) user equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, pagers, cellular phones, personal digital assistants (PDAs), smartphones, laptops, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of industrial and / or automated processing chains), consumer electronics devices, devices operating on commercial and / or industrial wireless networks, and the like. Any one of WTRUs 102a, 102b, 102c, and 102d may be interchangeably referred to as a UE.

[0030] The communication system 100 may also include base station 114a and / or base station 114b. Each of base stations 114a and 114b may be any type of device configured to wirelessly interface with at least one of WTRUs 102a, 102b, 102c, and 102d to facilitate access to one or more communication networks, such as CN 106 / 115, Internet 110, and / or Network 112. As an example, base stations 114a and 114b may be base transceiver stations (BTS), node Bs (NBs), eNode-Bs (eNBs), home node Bs (HNBs), home eNode-Bs (HeNBs), gNode-Bs (gNBs), NR node Bs (NR NBs), site controllers, access points (APs), wireless routers, and any of the like. Although each of base stations 114a and 114b is depicted as a single element, it will be appreciated that base stations 114a and 114b may include any number of interconnected base stations and / or network elements.

[0031] Base station 114a may be part of RAN 104 / 113, which may also include other base stations and / or network elements (not shown), such as base station controllers (BSCs), radio network controllers (RNCs), relay nodes, etc. Base station 114a and / or base station 114b may be configured to transmit and / or receive radio signals on one or more carrier frequencies, which may be referred to as cells (not shown). These frequencies may be licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. Cells may provide coverage for radio services to a specific geographic area that may be relatively fixed or may change over time. Cells may also be divided into cell sectors. For example, the cell associated with base station 114a may be divided into three sectors. Therefore, in an embodiment, base station 114a may include three transceivers, i.e., one transceiver per sector of the cell. In an embodiment, base station 114a may employ multiple-input multiple-output (MIMO) technology and may use multiple transceivers for each or any sector of the cell. For example, beamforming may be used to transmit and / or receive signals in a desired spatial direction.

[0032] Base stations 114a and 114b can communicate with one or more of WTRUs 102a, 102b, 102c, and 102d via air interface 116. Air interface 116 can be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, micrometer wave, infrared (IR), ultraviolet (UV), visible light, etc.). Any suitable radio access technology (RAT) can be used to establish air interface 116.

[0033] More specifically, as described above, the communication system 100 can be a multiple access system and can employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, and the like. For example, base stations 114a and WTRUs 102a, 102b, and 102c in RAN 104 / 113 can implement radio technologies such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA), which can use Wideband CDMA (WCDMA) to establish the air interface 116. WCDMA can include communication protocols such as High-Speed ​​Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA can include High-Speed ​​Downlink Packet Access (HSDPA) and / or High-Speed ​​Uplink Packet Access (HSUPA).

[0034] In the embodiment, base station 114a and WTRUs 102a, 102b, 102c can implement radio technologies such as Evolved UMTS Terrestrial Radio Access (E-UTRA), which can use Long Term Evolution (LTE) and / or LTE-A Advanced (LTE-A) and / or LTE-A Pro Advanced (LTE-A Pro) to establish air interface 116.

[0035] In the embodiment, base station 114a and WTRUs 102a, 102b, 102c can implement radio technologies such as NR radio access, which can use New Radio (NR) to establish air interface 116.

[0036] In the embodiments, base station 114a and WTRUs 102a, 102b, and 102c can implement multiple radio access technologies. For example, base station 114a and WTRUs 102a, 102b, and 102c can, for instance, use the dual connectivity (DC) principle to jointly implement LTE radio access and NR radio access. Therefore, the air interface utilized by WTRUs 102a, 102b, and 102c may be characterized by transmissions to / from multiple types of base stations (e.g., eNBs and gNBs) and / or multiple types of radio access technologies.

[0037] In the embodiments, base station 114a and WTRUs 102a, 102b, 102c can implement radio technologies such as IEEE 802.11 (i.e., WiFi), IEEE 802.16 (i.e., Global Microwave Access Interoperability (WiMAX)), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Provisional Standard 2000 (IS-2000), Provisional Standard 95 (IS-95), Provisional Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rate Evolution of GSM (EDGE), GSM EDGE (GERAN), and the like.

[0038] Figure 1ABase station 114b can be, for example, a wireless router, a home node B, a home eNode B, or an access point, and can utilize any suitable RAT to facilitate wireless connectivity in a local area, such as a commercial location, home, vehicle, campus, industrial facility, air corridor (e.g., for drone use), road, and the like. In embodiments, base station 114b and WTRUs 102c, 102d can implement radio technologies such as IEEE 802.11 to establish a wireless local area network (WLAN). In embodiments, base station 114b and WTRUs 102c, 102d can implement radio technologies such as IEEE 802.15 to establish a wireless personal area network (WPAN). In embodiments, base station 114b and WTRUs 102c, 102d can utilize cellular-based RATs (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish any cell, such as a small cell, pico cell, or femtocell. Figure 1A As shown, base station 114b can have a direct connection to the Internet 110. Therefore, it is not required that base station 114b access the Internet 110 via CN 106 / 115.

[0039] RAN 104 / 113 can communicate with CN 106 / 115, which can be any type of network configured to provide voice, data, application, and / or Voice over Internet Protocol (VoIP) services to one or more of WTRUs 102a, 102b, 102c, and 102d. Data can have different Quality of Service (QoS) requirements, such as different throughput requirements, latency requirements, fault tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, and the like. CN 106 / 115 can provide call control, billing services, location-based services, prepaid calling, internet connectivity, video distribution, and / or perform advanced security functions such as user authentication. Although Figure 1A Although not shown, it should be understood that RAN 104 / 113 and / or CN 106 / 115 can communicate directly or indirectly with other RANs that use the same RAT as or a different RAT than RAN 104 / 113. For example, in addition to being connected to RAN 104 / 113, which can utilize NR radio technology, CN 106 / 115 can also communicate with another RAN (not shown) that uses any of the following technologies: GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or Wi-Fi radio technology.

[0040] CN 106 / 115 can also serve as a gateway for WTRU 102a, 102b, 102c, 102d to access PSTN 108, the Internet 110, and / or other networks 112. PSTN 108 may include a circuit-switched telephone network providing Common Old-Style Telephone Service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices using common communication protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and / or Internet Protocol (IP) from the TCP / IP Internet Protocol suite. Network 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, network 112 may include another CN connected to one or more RANs, which may use the same RAT as RAN 104 / 113 or a different RAT.

[0041] Some or all of the WTRUs 102a, 102b, 102c, and 102d in communication system 100 may include multi-mode capabilities (e.g., WTRUs 102a, 102b, 102c, and 102d may include multiple transceivers for communicating with different wireless networks via different wireless links). For example, Figure 1A The WTRU 102c shown can be configured to communicate with a base station 114a that can employ cellular-based radio technology and a base station 114b that can employ IEEE 802 radio technology.

[0042] Figure 1B This is a system diagram illustrating example WTRU 102. (See diagram below.) Figure 1B As shown, WTRU 102 may, among other things, include a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, non-removable memory 130, removable memory 132, a power supply 134, a Global Positioning System (GPS) chipset 136, and / or other components / peripherals 138. It should be understood that WTRU 102 may include any sub-combination of the foregoing components while remaining consistent with the embodiments.

[0043] Processor 118 may be a general-purpose processor, a special-purpose processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, and the like. Processor 118 may perform signal encoding, data processing, power control, input / output processing, and / or any other functionality that enables WTRU 102 to operate in a wireless environment. Processor 118 may be coupled to transceiver 120, and transceiver 120 may be coupled to transmitting / receiving element 122. Although Figure 1B The processor 118 and transceiver 120 are depicted as separate components, but it should be understood that the processor 118 and transceiver 120 may be integrated together in, for example, an electronic package or chip.

[0044] Transmitting / receiving element 122 can be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via air interface 116. For example, in one embodiment, transmitting / receiving element 122 can be an antenna configured to transmit and / or receive RF signals. In another embodiment, transmitting / receiving element 122 can be a transmitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In yet another embodiment, transmitting / receiving element 122 can be configured to transmit and / or receive both RF signals and optical signals. It should be understood that transmitting / receiving element 122 can be configured to transmit and / or receive any combination of wireless signals.

[0045] Although the transmitting / receiving element 122 is in Figure 1B While depicted as a single element, WTRU 102 may include any number of transmit / receive elements 122. For example, WTRU 102 may employ MIMO technology. Therefore, in an embodiment, WTRU 102 may include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals via air interface 116.

[0046] Transceiver 120 can be configured to modulate signals to be transmitted by transmitting / receiving element 122 and demodulate signals received by transmitting / receiving element 122. As described above, WTRU 102 can have multi-mode capability. Therefore, transceiver 120 may include multiple transceivers for enabling WTRU 102 to communicate via various RATs, such as, for example, NR and IEEE 802.11.

[0047] The processor 118 of WTRU 102 can be coupled to a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) unit or an organic light-emitting diode (OLED) display unit), and can receive user input data therefrom. The processor 118 can also output user data to the speaker / microphone 124, keypad 126, and / or display / touchpad 128. Additionally, the processor 118 can access information from and store data therein from any type of suitable memory, such as non-removable memory 130 and / or removable memory 132. Non-removable memory 130 can include random access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. Removable memory 132 can include a subscriber identity module (SIM) card, memory stick, secure digital storage (SD) card, and the like. In other embodiments, the processor 118 can access information from and store data in memory that is not physically located on WTRU 102, such as on a server or home computer (not shown).

[0048] The processor 118 may receive power from the power supply 134 and may be configured to distribute and / or control power to other components in the WTRU 102. The power supply 134 may be any suitable device for powering the WTRU 102. For example, the power supply 134 may include one or more dry cell batteries (e.g., nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), etc.), solar cells, fuel cells, and the like.

[0049] The processor 118 may also be coupled to a GPS chipset 136, which may be configured to provide location information (e.g., longitude and latitude) about the current location of the WTRU 102. In addition to or instead of information from the GPS chipset 136, the WTRU 102 may receive location information from base stations (e.g., base stations 114a, 114b) via air interface 116 and / or determine its location based on the timing of signals received from two or more nearby base stations. It should be understood that the WTRU 102 may acquire location information using any suitable location determination method while remaining consistent with the embodiments.

[0050] The processor 118 may also be coupled to other components / peripherals 138, which may include one or more software and / or hardware modules / units providing additional features, functionality, and / or wired or wireless connectivity. For example, components / peripherals 138 may include accelerometers, electronic compasses, satellite transceivers, digital cameras (for photos and / or video), Universal Serial Bus (USB) ports, vibration devices, television transceivers, hands-free headsets, and Bluetooth. ® Modules, FM radio units, digital music players, media players, video game player modules, internet browsers, virtual reality and / or augmented reality (VR / AR) devices, activity trackers, and the like. Components / peripherals 138 may include one or more sensors, which may be one or more of the following: gyroscopes, accelerometers, Hall effect sensors, magnetometers, orientation sensors, proximity sensors, temperature sensors, time sensors; geolocation sensors; altimeters, light sensors, touch sensors, magnetometers, barometers, gesture sensors, biometric sensors, and / or humidity sensors.

[0051] WTRU 102 may include a full-duplex radio for which transmission and reception of some or all signals associated with specific subframes for both uplink (e.g., for transmission) and downlink (e.g., for reception) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit to reduce and / or substantially eliminate self-interference via hardware (e.g., chokes) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In embodiments, WTRU 102 may include a half-duplex radio for which transmission and reception of some or all signals associated with specific subframes for either uplink (e.g., for transmission) or downlink (e.g., for reception) may be concurrent and / or simultaneous.

[0052] Figure 1C This is a system diagram illustrating RAN 104 and CN 106 according to an embodiment. As described above, RAN 104 may employ E-UTRA radio technology to communicate with WTRUs 102a, 102b, and 102c via air interface 116. RAN 104 may also communicate with CN 106.

[0053] RAN 104 may include eNode-B 160a, 160b, 160c, but will be appreciated that RAN 104 may include any number of eNode-Bs while remaining consistent with the embodiments. Each of eNode-B 160a, 160b, 160c may include one or more transceivers for communicating with WTRU 102a, 102b, 102c via air interface 116. In the embodiments, eNode-B 160a, 160b, 160c may implement MIMO technology. Thus, for example, eNode-B 160a may use multiple antennas to transmit radio signals to and / or receive radio signals from WTRU 102a.

[0054] Each of the eNode-B 160a, 160b, and 160c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, user scheduling in the uplink (UL) and / or downlink (DL), and the like. Figure 1C As shown, eNode-B 160a, 160b, and 160c can communicate with each other via the X2 interface.

[0055] Figure 1C The CN 106 shown may include a Mobility Management Entity (MME) 162, a Serving Gateway (SGW) 164, and a Packet Data Network (PDN) Gateway (PGW) 166. While each of the foregoing elements is depicted as part of CN 106, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0056] The MME 162 can connect to each of the eNode-Bs 160a, 160b, and 160c in RAN 104 via the S1 interface and can be used as a control node. For example, the MME 162 can be responsible for authenticating users of WTRUs 102a, 102b, and 102c, bearer activation / deactivation, selecting a specific serving gateway during the initial attachment of WTRUs 102a, 102b, and 102c, and the like. The MME 162 can provide control plane functions for handover between RAN 104 and other RANs (not shown) employing other radio technologies such as GSM and / or WCDMA.

[0057] The SGW 164 can connect to each of the eNode Bs 160a, 160b, and 160c in RAN 104 via the S1 interface. The SGW 164 can typically route and forward user data packets to / from WTRUs 102a, 102b, and 102c. The SGW 164 can perform other functions such as anchoring the user plane during inter-eNode B handover, triggering paging when DL data is available for WTRUs 102a, 102b, and 102c, managing and storing the context of WTRUs 102a, 102b, and 102c, and so on.

[0058] The SGW 164 can connect to the PGW 166, which provides WTRU 102a, 102b, and 102c with access to packet-switched networks such as the Internet 110, facilitating communication between WTRU 102a, 102b, and 102c and IP-enabled devices.

[0059] CN 106 can facilitate communication with other networks. For example, CN 106 can provide WTRUs 102a, 102b, and 102c with access to circuit-switched networks such as PSTN 108 to facilitate communication between WTRUs 102a, 102b, and 102c and traditional landline communication equipment. For example, CN 106 may include, or be able to communicate with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between CN 106 and PSTN 108. Furthermore, CN 106 can provide WTRUs 102a, 102b, and 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers.

[0060] Despite Figure 1A-1D While the WTRU is described as a wireless terminal, it is conceivable that in some representative embodiments, such a terminal may use (e.g., temporarily or permanently) a wired communication interface with a communication network.

[0061] In a representative embodiment, the other network 112 may be a WLAN.

[0062] A WLAN in Infrastructure Basic Services Set (BSS) mode can have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP may have access or an interface to a distribution system (DS) or another type of wired / wireless network that carries traffic into and / or out of the BSS. Traffic originating outside the BSS to a STA can reach and be delivered to the STA via the AP. Traffic originating from a STA to a destination outside the BSS can be sent to the AP for delivery to the appropriate destination. Traffic between STAs within the BSS can be sent via the AP, for example, where a source STA can send traffic to the AP, and the AP can deliver the traffic to the destination STA. Traffic between STAs within the BSS can be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic can be sent between a source STA and a destination STA (e.g., directly between the source STA and the destination STA) using Direct Link Establishment (DLS). In some representative embodiments, the DLS may use 802.11e DLS or 802.11z Tunneling DLS (TDLS). WLANs using Standalone BSS (IBSS) mode may not have access points (APs), and STAs within the IBSS or using the IBSS (e.g., all STAs) can communicate directly with each other. The IBSS communication mode may sometimes be referred to as the "ad-hoc" communication mode in this document.

[0063] When using 802.11ac infrastructure operating mode or a similar operating mode, the AP can transmit beacons on a fixed channel, such as the primary channel. The primary channel can be of fixed width (e.g., a bandwidth of 20 MHz) or dynamically set via signaling. The primary channel can be the operating channel of the BSS and can be used by the STA to establish a connection with the AP. In some representative embodiments, carrier-sense multiple access (CSMA / CA) with collision avoidance can be implemented, for example, in an 802.11 system. For CSMA / CA, STAs including the AP (e.g., each STA) can sense the primary channel. If the primary channel is sensed / detected and / or determined to be busy by a particular STA, that particular STA can back off. A single STA (e.g., only one station) can transmit at any given time within a given BSS.

[0064] High-throughput (HT) STAs can communicate using a 40 MHz wide channel, for example, by combining a primary 20 MHz channel with adjacent or non-adjacent 20 MHz channels.

[0065] Very High Throughput (VHT) STAs can support wide channels of 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz. A 40 MHz and / or 80 MHz channel can be formed by combining consecutive 20 MHz channels. A 160 MHz channel can be formed by combining eight consecutive 20 MHz channels or by combining two non-consecutive 80 MHz channels; this can be referred to as an 80+80 configuration. For the 80+80 configuration, after channel coding, data passes through a segmentation parser, which divides the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time-domain processing can be performed separately for each stream. The streams can be mapped onto two 80 MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the above operations for the 80+80 configuration can be reversed, and the combined data can be sent to Media Access Control (MAC), entities, etc.

[0066] The sub-1 GHz operating mode is supported by 802.11af and 802.11ah. The channel operating bandwidth and carrier are reduced in 802.11af and 802.11ah compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV white space (TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support instrument-type control / machine-type communication (MTC), such as MTC devices in macro coverage areas. MTC devices may have certain capabilities, such as limited capabilities, including support (e.g., only support) certain and / or limited bandwidths. MTC devices may include batteries with a battery life exceeding a threshold (e.g., to maintain a very long battery life).

[0067] WLAN systems supporting multiple channels and channel bandwidths, such as 802.11n, 802.11ac, 802.11af, and 802.11ah, include a channel that can be designated as the primary channel. The primary channel can have a bandwidth equal to the maximum common operating bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel can be set and / or limited by the STAs operating in the BSS that support the minimum bandwidth operating mode. In the 802.11ah example, for STAs supporting (e.g., only supporting) the 1 MHz mode (e.g., MTC type devices), the primary channel can be 1 MHz wide, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operating modes. Carrier sensing and / or Network Allocation Vector (NAV) settings can depend on the status of the primary channel. If the primary channel is busy, for example, because an STA (which only supports the 1 MHz operating mode) is transmitting to the AP, then all available bands can be considered busy even if most bands remain idle and are likely available.

[0068] In the United States, the available frequency bands for 802.11ah are from 902 MHz to 928 MHz. In South Korea, the available frequency bands are from 917.5 MHz to 923.5 MHz. In Japan, the available frequency bands are from 916.5 MHz to 927.5 MHz. Depending on the country code, the total bandwidth available for 802.11ah ranges from 6 MHz to 26 MHz.

[0069] Figure 1D This is a system diagram illustrating RAN 113 and CN 115 according to an embodiment. As described above, RAN 113 can employ NR radio technology to communicate with WTRUs 102a, 102b, and 102c via air interface 116. RAN 113 can also communicate with CN 115.

[0070] RAN 113 may include gNBs 180a, 180b, and 180c; however, it should be understood that RAN 113 may include any number of gNBs while remaining consistent with the embodiments. Each of gNBs 180a, 180b, and 180c may include one or more transceivers for communicating with WTRUs 102a, 102b, and 102c via air interface 116. In the embodiments, gNBs 180a, 180b, and 180c may implement MIMO technology. For example, gNBs 180a and 180b may utilize beamforming to transmit signals to and / or receive signals from WTRUs 102a, 102b, and 102c. Therefore, gNB 180a may, for example, use multiple antennas to transmit radio signals to and / or receive radio signals from WTRU 102a. In embodiments, gNBs 180a, 180b, and 180c can implement carrier aggregation technology. For example, gNB 180a can transmit multiple component carriers to WTRU 102a (not shown). A subset of these component carriers can be on unlicensed spectrum, while the remaining component carriers can be on licensed spectrum. In embodiments, gNBs 180a, 180b, and 180c can implement Cooperative Multipoint (CoMP) technology. For example, WTRU 102a can receive cooperative transmissions from gNBs 180a and 180b (and / or gNB 180c).

[0071] WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using transmissions associated with scalable numberology. For example, OFDM symbol spacing and / or OFDM subcarrier spacing can vary for different transmissions, different cells, and / or different portions of the radio transmission spectrum. WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c using subframes or transmission time intervals (TTIs) of various or scalable lengths (e.g., including different numbers of OFDM symbols and / or absolute times of varying durations).

[0072] gNBs 180a, 180b, and 180c can be configured to communicate with WTRUs 102a, 102b, and 102c in standalone and / or non-standalone configurations. In standalone configuration, WTRUs 102a, 102b, and 102c can communicate with gNBs 180a, 180b, and 180c without also accessing other RANs (e.g., eNode-Bs 160a, 160b, and 160c). In standalone configuration, WTRUs 102a, 102b, and 102c can utilize one or more of gNBs 180a, 180b, and 180c as mobility anchors. In standalone configuration, WTRUs 102a, 102b, and 102c can use signals in unlicensed frequency bands to communicate with gNBs 180a, 180b, and 180c. In a non-standalone configuration, WTRUs 102a, 102b, and 102c can communicate with / connect to gNBs 180a, 180b, and 180c, while also communicating with / connecting to another RAN such as eNode-Bs 160a, 160b, and 160c. For example, WTRUs 102a, 102b, and 102c can implement DC principles to communicate substantially simultaneously with one or more gNBs 180a, 180b, and 180c and one or more eNode-Bs 160a, 160b, and 160c. In a non-standalone configuration, eNode-B160a, 160b, and 160c can be used as mobility anchors for WTRU 102a, 102b, and 102c, and gNB 180a, 180b, and 180c can provide additional coverage and / or throughput for serving WTRU 102a, 102b, and 102c.

[0073] Each of gNBs 180a, 180b, and 180c can be associated with a specific cell (not shown) and can be configured to handle radio resource management decisions, handover decisions, user scheduling in UL and / or DL, network slicing support, dual connectivity, interoperability between NR and E-UTRA, routing of user plane data to User Plane Functions (UPF) 184a and 184b, routing of control plane information to Access and Mobility Management Functions (AMF) 182a and 182b, and the like. Figure 1D As shown, gNB 180a, 180b, and 180c can communicate with each other via the Xn interface.

[0074] Figure 1DThe CN 115 shown may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one Session Management Function (SMF) 183a, 183b, and at least one Data Network (DN) 185a, 185b. While each of the foregoing elements is depicted as part of the CN 115, it should be understood that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0075] AMF 182a and 182b can connect to one or more of gNBs 180a, 180b, and 180c in RAN 113 via the N2 interface and can be used as control nodes. For example, AMF 182a and 182b can be responsible for authenticating users of WTRU 102a, 102b, and 102c, supporting network slicing (e.g., handling different Protocol Data Unit (PDU) sessions with different requirements), selecting specific SMF 183a and 183b, managing registration areas, terminating NAS signaling, mobility management, and the like. AMF 182a and 182b can use network slicing, for example, to customize CN support for WTRU 102a, 102b, and 102c based on the type of service being used by WTRU 102a, 102b, and 102c. For example, different network slices can be created for different use cases, such as services that rely on Ultra Reliable Low Latency (URLLC) access, services that rely on Enhanced Massive Mobile Broadband (eMBB) access, services for MTC access, and / or similar services. AMF 162 provides control plane functions for handover between RAN 113 and other RANs (not shown) employing other radio technologies, such as LTE, LTE-A, LTE-A Pro, and / or non-3GPP access technologies, such as WiFi.

[0076] SMFs 183a and 183b can connect to AMFs 182a and 182b in CN 115 via the N11 interface. SMFs 183a and 183b can also connect to UPFs 184a and 184b in CN 115 via the N4 interface. SMFs 183a and 183b can select and control UPFs 184a and 184b, and configure the routing of traffic through UPFs 184a and 184b. SMFs 183a and 183b can perform other functions such as managing and allocating UE IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing downlink data notifications, and so on. PDU session types can be IP-based, non-IP-based, Ethernet-based, and so on.

[0077] UPF 184a and 184b can be connected via an N3 interface to one or more gNBs 180a, 180b, and 180c in RAN 113. This N3 interface provides WTRU 102a, 102b, and 102c with access to packet-switched networks, such as the Internet 110, to facilitate communication between WTRU 102a, 102b, and 102c and IP-enabled devices. UPF 184 and 184b can perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering downlink packets, providing mobility anchoring, and so on.

[0078] CN 115 can facilitate communication with other networks. For example, CN 115 may include, or be able to communicate with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) serving as an interface between CN 115 and PSTN 108. Furthermore, CN 115 can provide WTRUs 102a, 102b, 102c with access to other networks 112, which may include other wired and / or wireless networks owned and / or operated by other service providers. In an embodiment, WTRUs 102a, 102b, 102c may be connected to local data networks (DNs) 185a, 185b via the N3 interface to UPFs 184a, 184b and the N6 interface between UPFs 184a, 184b and DNs 185a, 185b.

[0079] Given Figure 1A-1D and to Figure 1A-1D The corresponding descriptions herein refer to the following: One or more of the functions described in the WTRU 102a-d, Base Station 114a-b, eNode-B 160a-c, MME 162, SGW 164, PGW 166, gNB 180a-c, AMF 182a-b, UPF 184a-b, SMF 183a-b, DN 185a-b, and / or any other element / device described herein may be performed by one or more emulation elements / devices (not shown). An emulation device may be one or more devices configured to emulate one or more of the functions described herein. For example, an emulation device may be used to test other devices and / or simulate network and / or WTRU functions.

[0080] Simulation devices can be designed to perform one or more tests on other devices in a laboratory environment and / or a carrier network environment. For example, one or more simulation devices may perform one or more or all of their functions while being fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices within the communication network. One or more simulation devices may perform one or more or all of their functions while being temporarily implemented / deployed as part of a wired and / or wireless communication network. Simulation devices may be directly coupled to another device for testing using over-the-air wireless communication and / or for the purpose of performing tests.

[0081] One or more simulation devices may perform one or more (including all) functions without being implemented / deployed as part of a wired and / or wireless communication network. For example, simulation devices may be used to test test scenarios in a laboratory and / or non-deployed (e.g., testing) wired and / or wireless communication networks to perform testing of one or more components. One or more simulation devices may be test equipment. Simulation devices may transmit and / or receive data using direct RF coupling and / or wireless communication via RF circuitry (e.g., which may include one or more antennas).

[0082] introduce Measurement In RRC_CONNECTED, WTRU 102 can measure one or more of the multiple beams of a cell. WTRU 102 can average the measurement results (e.g., power values) to derive (e.g., determine) the cell quality corresponding to the cell. For example, WTRU 102 can be configured to consider a subset of the detected beams. Filtering can be performed at two different levels: filtering at the physical layer to derive beam quality, and then filtering at the RRC layer to derive cell quality from multiple beams. For serving cells(one or more) and non-serving cells(one or more), the cell quality from the beam measurements can be derived in the same manner. The measurement report can contain the measurement results of X best beams, such as in the example where WTRU 102 has been configured by gNB 180 to do so.

[0083] Figure 2 This is a block diagram illustrating an example of a measurement model. Figure 2 At point A in the diagram, WTRU 102 can perform one or more measurements within the physical layer (e.g., beam-specific samples). At L1 filtering block 202, WTRU 102 can perform internal L1 filtering on the input measured at point A. For example, the filtering can vary depending on the implementation. The exact filtering can be implementation-dependent. Performing measurements at the physical layer (e.g., input A and L1 filtering) through implementation is not subject to normalization constraints.

[0084] exist Figure 2 A in 1 At this point, measurements (e.g., beam-specific measurements) can be reported from layer 1 to layer 3 after layer 1 filtering. At beam combining / selection box 204, WTRU 102 can combine beam-specific measurements to derive cell quality information for the corresponding cell. The behavior of beam combining / selection can be standardized. For example, RRC signaling can configure parameters associated with beam combining / selection.

[0085] exist Figure 2 At point B in the diagram, measurement information derived from beam-specific measurements (e.g., cell quality) can be reported to layer 3 after beam combining / selection box 204. For example, the reporting period at point B can correspond to (e.g., equal to) point A. 1 A measurement period at point B. At the Layer 3 filtering frame 206 for cell quality, WTRU 102 can perform filtering on the measurements provided at point B. For example, the behavior of the Layer 3 filter can be normalized. For example, RRC signaling can configure parameters associated with the Layer 3 filter.

[0086] exist Figure 2 At point C, the measurement after processing in layer 3 filter box 206 can be provided. The measurement can be used as input to one or more evaluations of the reporting criteria. For example, the filtered reporting period at point C can correspond to (e.g., equal to) a measurement period at point B. The filtered reporting rate at point C can correspond to (e.g., equal to) the rate at point B. At the evaluation box 208 of the reporting criteria, WTRU 102 can check whether actual measurement reporting is necessary. The evaluation can be based on more than one measurement stream at reference point C (e.g., for comparison between different measurements). Figure 2 In this case, it is determined by inputs C and C. 1 As shown. WTRU 102 can (e.g., should) at least each time at point C and / or C 1 When reporting new measurement results, reporting standards are evaluated. Reporting standards can be standardized. For example, RRC signaling can configure parameters associated with the evaluation of reporting standards.

[0087] exist Figure 2 At point D in the diagram, WTRU 102 can send measurement report information (e.g., in a message) to a network, such as gNB 180, via the radio interface.

[0088] exist Figure 2 At L3 beam filter frame 210, WTRU 102 can target point A. 1 The measurements provided (e.g., beam-specific measurements) are filtered. For example, the behavior of the beam filter can be normalized. For example, RRC signaling can configure parameters associated with the configuration of the beam filter.

[0089] exist Figure 2 At point E, the processed measurements (e.g., beam-specific measurements) in the L3 beam filtering box 210 can be provided. For example, the measurements can be used as inputs for selecting X measurements to be reported. For example, the filtered reporting period at point E can correspond to (e.g., equal to) A. 1 A measurement period at point A. The filter reporting rate can be compared with that at point A. 1 The reporting rate is the same at each location.

[0090] At beam selection box 212 for beam reporting, WTRU 102 can select X measurements from those provided at E. The behavior of beam selection can be standardized. For example, RRC signaling can configure parameters associated with beam selection.

[0091] exist Figure 2 At point F, the WTRU can send beam measurement information (e.g., in a beam measurement report) to the network, such as to the gNB 180, via the radio interface.

[0092] For example, Layer 1 filtering can introduce (e.g., include) a certain level of measurement averaging. How and when exactly WTRU 102 performs the required measurements can be an implementation of the point where the output at point B meets the performance requirements specified in TS 38.133. Layer 3 filtering for cell quality and the relevant parameters used are specified in TS 38.331 and may not introduce any delay in sample availability between B and C. Figure 2 In the middle, C 1 This is the input used in event assessment. The L3 beam filtering and the relevant parameters used are specified in TS 38.331 and may not introduce any delay in sample availability between E and F.

[0093] For example, a measurement report may include the measurement identity of the associated measurement configuration that triggered the report. The measurement report may include cell and / or beam measurements configured by the network. The number of non-serving cells to be reported can be limited by network configuration. Cells belonging to an exclusion list configured by the network may be excluded from event assessment and reporting. Cells belonging to an allow list can be configured by the network. For example, (e.g., only) cells belonging to the allow list may be used in event assessment and reporting. Beam measurements to be included in the measurement report can be configured by the network (e.g., only beam identifier, measurement result and beam identifier, or no beam report).

[0094] For example, intra-frequency neighbor (e.g., cell) measurements and inter-frequency neighbor (e.g., cell) measurements can include measurements based on synchronization signal blocks (SSBs) and / or intra-frequency measurements based on channel state information reference signals (CSI-RS). For example, an SSB-based intra-frequency measurement can refer to an SSB-based intra-frequency measurement where the center frequency of the serving cell's SSB is the same as the center frequency of the neighboring cell's SSB and / or the subcarrier spacing of the two SSBs is the same. For example, an SSB-based inter-frequency measurement can refer to an SSB-based intra-frequency measurement where the center frequency of the serving cell's SSB is different from the center frequency of the neighboring cell's SSB, and / or the subcarrier spacing of the two SSBs is different. For SSB-based measurements, one measurement object can correspond to one SSB, and WTRU 102 treats different SSBs as different cells.

[0095] For example, a CSI-RS-based intra-frequency measurement can be described as a measurement in which the subcarrier spacing (SCS) of the CSI-RS resources configured for measurement on a neighboring cell is the same as the SCS of the CSI-RS resources indicated for measurement on the serving cell. For example, for a 60 kHz subcarrier spacing, the CP type of the CSI-RS resources configured for measurement on a neighboring cell can be the same as the CP type of the CSI-RS resources indicated for measurement on the serving cell. For example, a CSI-RS-based intra-frequency measurement can be described as a measurement in which the center frequency of the CSI-RS resources configured for measurement on a neighboring cell is the same as the center frequency of the CSI-RS resources indicated for measurement on the serving cell.

[0096] For example, CSI-RS-based inter-frequency measurements can be referred to as measurements other than CSI-RS-based intra-frequency measurements (e.g., using CSI-RS resources). For example, extended CP may (or may not) be supported for CSI-RS-based measurements.

[0097] For example, depending on the WTRU's capabilities, its active BWP, and / or (e.g., current) operating frequency, the measurement may be referred to as non-gap-assisted or gap-assisted. For SSB-based inter-frequency measurements, where measurement gap requirement information is reported by WTRU102, measurement gap configuration can be provided based on this information. Otherwise, measurement gap configuration can (e.g., always) be provided when: the WTRU supports only one measurement gap per WTRU, and / or the WTRU supports one FR measurement gap per WTRU, and any serving cell is within the same frequency range of the measurement object. For SSB-based intra-frequency measurements, where measurement gap requirement information is reported by WTRU, measurement gap configuration can be provided based on this information. Otherwise, measurement gap configuration can (e.g., always) be provided when: any configured BWP (e.g., other than the initial BWP) does not contain frequency domain resources of the SSB associated with the initial DL BWP.

[0098] In the non-gap-assisted example, WTRU 102 can (e.g., should) be able to perform such a measurement without a measurement gap. In the gap-assisted scenario, WTRU 102 may not (e.g., cannot) be assumed to be able to perform such a measurement without a measurement gap.

[0099] Inter-cell L1 / L2 triggered mobility (LTM) Currently, 5G NR Release 17 (R17) can use inter-cell beam management, which can manage beams in carrier aggregation (CA) scenarios, but does not support cell changes and / or additions. In 5G NR Release 18 (R18), one of the goals of work item "Further NR Mobility Enhancements" in RP-213565 is to specify the mechanisms and procedures for L1 / L2 based inter-cell mobility for mobility latency reduction, as follows: 1. To specify the mechanisms and processes for L1 / L2-based inter-cell mobility for mobility latency reduction: • Configuration and maintenance of multiple candidate cells to allow for rapid application of candidate cell configurations [RAN2, RAN3] • Dynamic handover mechanism between candidate serving cells (including SpCell and SCell) based on potential application scenarios of L1 / L2 signaling [RAN2, RAN1] • L1 enhancements for inter-cell beam management, including L1 measurement and reporting, and beam indication [RAN1, RAN2] - Note 1: Early RAN2 participation is necessary, including further clarification of the project bullet and previous items. The possibility of interaction between symbolic objects • Scheduled advance management [RAN1, RAN2] • Supports CU-DU interface signaling for L1 / L2 mobility, if required [RAN3] Note 2: FR2-specific enhancements are not excluded, if any.

[0100] Note 3: The process based on L1 / L2 inter-cell mobility is applicable to the following scenarios: ▪ Independent CA and NR-DC scenarios with serving cell changes within a CG ▪ Intra-DU and intra-CU DU scenarios (applicable to standalone and CA: no new RAN interface expected) ▪ Both within and between frequencies ▪ Both FR1 and FR2 ▪ The source cell and the target cell can be synchronized or asynchronous. ▪ Excluding cases between CUs.

[0101] L1 / L2-based mobility was first introduced in R17, and inter-cell beam management in R17 addresses intra-DU and intra-frequency scenarios. In this case, the serving cell can remain unchanged (e.g., there is no possibility of changing the serving cell using L1 / 2-based mobility). In FR2 deployments, CA is typically used to utilize available bandwidth, such as aggregating multiple component carriers (CCs) in a frequency band. CCs typically utilize the same analog beam pairs (e.g., gNB beams and WTRU beams) for transmission. WTRU 102 can be configured with TCI states (e.g., 64 TCI states) for receiving PDCCH and PDSCH. Each TCI state can include an RS or SSB, which WTRU 102 references to set its beam. For R17, the SSB can be associated with a non-serving physical cell ID (PCI). MAC signaling (e.g., "TCI state indication for UE-specific PDCCH MAC CE") activates the TCI states of the Coreset / PDCCH. MAC CE indicating the TCI state associated with a non-serving PCI supports PDCCH reception from a non-serving cell. MAC signaling (e.g., "TCI state activation / deactivation for UE-specific PDSCH") activates a subset of up to eight TCI states for PDSCH reception. DCI indicates which of the eight TCI states. R17 also supports "unified TCI states" with different update mechanisms (e.g., DCI-based) but without multiple TRPs. R18 is expected to support unified TCI states with multiple TRPs.

[0102] The overall goal of LTM is to improve handover latency. Using legacy L3 handover (HO) or conditional handover (CHO), the WTRU102 can typically first send a measurement report using RRC signaling. In response, the network can provide further measurement configuration and potential conditional handover configuration. With legacy L3 handover, the network provides the target cell configuration after the WTRU102 reports that the target cell meets the configured radio quality criteria using RRC signaling. With legacy conditional handover, to reduce the handover failure rate due to the delay in sending measurement reports and then receiving RRC reconfiguration, the network pre-provides the target cell configuration and the measurement criteria for determining when the WTRU102 should trigger CHO configuration. However, both L3 handover methods suffer from a certain amount of latency due to sending measurement reports and receiving target configuration, especially in the case of non-conditional handover.

[0103] One of the goals of LTM is to allow the rapid application of candidate cell configurations, including dynamic handovers between SCells and handovers between PCells (e.g., switching roles between SCells and PCells), without executing RRC signaling. Centralized cell (CU) inter-process handovers are excluded because this requires repositioning the PDCP anchor and has been excluded from the work items. Therefore, at least an RRC-based approach is required to support CU inter-process handovers.

[0104] Furthermore, using the legacy L3 handover mechanism, any currently active SCell(s) are released before the WTRU 102 moves to complete the handover to the target cell in the coverage area of ​​the new site. Scells can only be added back after a successful handover, leading to a degradation in throughput during the handover period. Therefore, one of the goals of L1 / 2 is to enable CA operation immediately when the serving cell changes.

[0105] Figure 3 This is a system diagram illustrating an example of LTM operation. Candidate cell groups can be configured by RRC. Dynamic handover between PCell and SCell can be implemented by WTRU 102 using L1 / 2 signaling.

[0106] exist Figure 3In this configuration, RRC signaling can configure WTRU 102 with cells 1, 2, 3, and 4 as candidate cell groups. As an example only, cell 1 302 can operate at 3.5 GHz, cell 2 304 at 2.1 GHz, cell 3 306 at 26 GHz, and / or cell 4 308 at 26 Hz. Cell 1 302 can be activated as a Pcell. Cell 2 304 can be activated as an Scell. WTRU 102 can perform dynamic Scell ​​handover between cells 2 304, 3 306, and / or 4 308 (e.g., during mobility). WTRU 102 can also perform dynamic Pcell handover between cells 1 302 and 2 304 (e.g., during mobility).

[0107] In March 2023, RAN Working Group 2 (RAN2) approved the baseline procedures for LTM. Figure 4 This is a process diagram illustrating the baseline procedure for LTM. At 402, WTRU 102 can be in an RRC connected state with the network (e.g., gNB 180). Figure 4 At position 404, WTRU 102 can send to gNB 180. Measurement Report The gNB 180 can determine whether to use LTM and can initiate candidate cell preparation (one or more).

[0108] At 406, gNB 180 can prepare LTM candidate cell configuration, and at 408, gNB 180 can transmit an RRCReconfiguration message to WTRU 102, which includes LTM candidate cell configuration of one or more candidate cells.

[0109] At position 410, WTRU 102 stores the LTM candidate cell configuration and can transmit the RRCReconfigurationComplete message to the gNB.

[0110] At 412, WTRU 102 may perform DL synchronization and / or timing advance (TA) acquisition with one or more candidate cells prior to receiving a cell handover command. For example, DL synchronization with one or more candidate cells prior to a cell handover command may be (e.g., at least) based on SSB. For example, TA acquisition with one or more candidate cells prior to an LTM cell handover command may be (e.g., at least) based on RACH of a PDCCH command, where the PDCCH command is triggered only by the source cell. At 414, WTRU 102 may perform UL synchronization with one or more candidate cells prior to receiving a cell handover command.

[0111] At 416, WTRU 102 can perform L1 measurements on configured candidate cells(s) and can transmit (e.g., report) lower-layer measurements to the gNB. For example, lower-layer measurement reports can be carried on L1 or MAC. For example, DL synchronization, UL synchronization, and / or L1 measurement reports can be changed and / or modified (e.g., Figure 4 The order of 412, 414, and 416 in the table.

[0112] At 418, gNB 180 can make an LTM decision, and at 420, it can determine whether to perform a cell handover to the target cell. At 420, gNB 180 can transmit a MAC CE that triggers the cell handover. For example, gNB 180 may include information indicating a candidate configuration index for the target cell. At 422, WTRU 102 can switch to the configuration of the target cell. For example, gNB 180 may provide information indicating one or more beams of the target cell.

[0113] At 424, WTRU 102 can perform a random access procedure toward the target cell, such as when a cell handover is required.

[0114] At 426, WTRU 102 can indicate successful completion of a cell handover to the target cell. For example, WTRU 102 can send uplink signals and / or messages to indicate successful completion of an LTM cell handover to the target cell.

[0115] For example, WTRU 102 can perform 412 to 426 once or more for subsequent LTM cell handovers based on the configuration provided at 408.

[0116] As mentioned above, inter-CU handover scenarios are excluded because they require repositioning the PDCP anchor and have been removed from the work items. Therefore, an RRC-based approach can be provided to support inter-CU handover, such as for DU / CU partitioning architectures. For example, the inter-CU handover process can be used in conjunction with the LTM process for intra-CU, intra-DU, and / or inter-DU handover. For example, when configuring LTM and LTM-supporting measurement and measurement reporting mechanisms, RRC-based measurement and mobility can be performed in parallel with LTM-supporting measurement and measurement reporting mechanisms.

[0117] Figure 5This is a system diagram illustrating examples of handover within and between CUs. By way of example only, LTM can be used for mobility between cells 1 502, 3 504, and 4 506 belonging to the first CU, and LTM can be used for mobility between cells 2 508, 5 510, and 6 512 belonging to the second CU. L3 mobility can be used for mobility between cells belonging to the first and second DUs, for example, for handover from cell 1 502 to cell 2 508 (e.g., measurement reporting and RRC reconfiguration and / or conditional reconfiguration (CHO)).

[0118] For example, LTM can use L1 measurement reports and MAC CE triggers to perform reconfiguration (handover). Similarly, L3 mobility can use L3 measurements and RRC triggers for reconfiguration. For several reasons, the latency of L1 measurements and MAC triggers can be expected to be significantly lower than that of L3 measurements and RRC triggers. First, measurement filtering performed at L1 can be completed on a shorter timescale than measurement filtering performed at L3, and measurement event evaluation at L1 can be expected to be performed on a shorter timescale than L3 measurement evaluation using relatively longer trigger times. L3 measurement evaluation can be performed using longer filtering and longer trigger times because handover using L3 signaling is relatively expensive in terms of overhead, and service interruptions should only be performed when necessary—trigger times and filtering are designed to reduce the likelihood of ping-pong between cells and ensure stable target cell measurements before handover. L1 mobility means lower costs in terms of overhead and service interruptions due to the use of pre-configured cell configurations, faster handover execution times, and further enhancements such as avoiding full MAC resets when performing handovers within a DU and when performing UL and DL synchronization before performing cell changes. Therefore, measurements can be performed more quickly to improve latency and handover failure / radio link failure rates, at the cost of a higher ping-pong rate, which, as explained, has a lower cost than utilizing L3 mobility. Consequently, any changes in cell quality can be detected at L1 earlier than at L3.

[0119] Secondly, LTM can be controlled by the DU (e.g., the source DU in the case of inter-DU mobility), while L3 mobility (e.g., RRC) is controlled by the CU. RRC signaling between WTRU 102 and the CU may be slower than L1 / L2 signaling between WTRU 102 and the DU. RRC signaling can be transmitted via the DU using the L1 / 2 protocol layer, and MAC / L1 signaling can be terminated at the DU. RRC signaling may be more reliable than using (e.g., using only) L2 due to the use of RRC acknowledgments (e.g., RRC reconfiguration complete), RLC AM (e.g., ARQ), and MAC (e.g., HARQ). Multi-level acknowledgments imply further latency and delay.

[0120] For these reasons, several potential race conditions exist when configuring LTM. Race conditions can refer to conditions that exist between different measurement and reporting types and / or different handover triggering signaling mechanisms. Problems include any of the following: (1) premature mobility outside the LTM area, (2) delayed and / or blocked mobility outside the LTM area, (3) a race condition in which WTRU 102 receives signaling for both L3 mobility and L1 / 2 mobility, and / or (4) a race condition in which WTRU 102 triggers an L3 measurement report and performs an L2 mobility procedure before successfully delivering the L3 report.

[0121] Regarding premature mobility outside the LTM area, in some scenarios, even if there are appropriately configured LTM candidates, L3 measurement events can be triggered based on a comparison between the current serving cell and neighboring cells.

[0122] Regarding the latency or congestion of mobility outside the LTM region, in some scenarios, it can prevent the triggering of L3 measurement events because frequent L2 triggering switching can reset the L3 measurement evaluation.

[0123] In addition, race conditions may exist where WTRU 102 receives signaling for (e.g., both) L3 mobility controllable by CU and L1 and / or L2 mobility controllable by DU.

[0124] Additionally, a race condition may exist where WTRU 102 has already triggered an L3 measurement report. The L2 mobility procedure is executed before WTRU 102 successfully delivers the L3 report.

[0125] Overview Abbreviations and acronyms The following abbreviations and acronyms may be used in this article.

[0126] ACK confirmation BLER block error rate BWP bandwidth portion CA carrier aggregation CAP channel access priority CAPC Channel Access Priority Class CCA Idle Channel Assessment CCE Control Channel Element CE control elements CG configuration authorization or cell group CHO conditional switching CP cyclic prefix CP-OFDM vs. Conventional OFDM (depending on the cyclic prefix) CPA can add PsCell under certain conditions. CPAC allows conditional addition / modification of PsCell. CPC conditional PsCell change CQI Channel Quality Indicator CRC Cyclic Redundancy Check CSI Channel State Information CW Competition Window CWS Competition Window Size CO channel occupancy DAI Downlink Allocation Index DC dual connectivity DCI Downlink Control Information DFI downlink feedback information DG Dynamic Licensing DL downlink DM-RS demodulation reference signal DRB Data Radio Bearer eLAA Enhanced Licensing Assisted Access FeLAA Further Enhanced Licensed Assisted Access HARQ Hybrid Automatic Repeat Request LAA Licensed Assisted Access LBT Listen before you speak LTE, for example, from 3GPP LTE R8 and above Long Term Evolution. LTM L1 / 2 triggered mobility NACK (Negative) MCG Main Cell Group MAC Media Access Control MCS modulation and coding scheme MIMO (Multiple Input Multiple Output) NR New Radio OFDM (Orthogonal Frequency Division Multiplexing) PCell main cell PCIP Physical Cell Identity PHY physical layer PID process ID PO paging timing PRACH (Physical Random Access Channel) PSCell main SCG cell PSS Master Synchronization Signal RA (Random Access or Procedure) RACH Random Access Channel RAR Random Access Response RCU Radio Access Network Central Unit RF radio front end RLC Radio Link Control RLF radio link failure RLM radio link monitoring RNTI Radio Network Identifier RO RACH timing RRC Radio Resource Control RRM Radio Resource Management RS reference signal RSRP reference signal received power RSSI Received Signal Strength Indicator SCell Auxiliary Community SCG Auxiliary Community Group SDU Service Data Unit SpCell Special Cell SRS Detection Reference Signal SS synchronization signal SSS auxiliary synchronization signal SWG switching interval (in a self-contained subframe) SPS (Semi-Persistent Scheduling) SUL supplements uplink TB transfer block TBS (Transfer Block Size) TRP Transmit / Receive Point TSC Time-Sensitive Communication TSN Time-Sensitive Networking UL uplink URLLC: Ultra-Reliable and Low-Latency Communication WBWP wide bandwidth portion WLAN (Wireless Local Area Network) and related technologies (IEEE 802.xx domain) As used herein, the term SpCell may refer to either the PCell of the MCG or the PSCell of the SCG (e.g., depending on whether the MAC entity is associated with the MCG or the SCG).

[0127] In some representative embodiments, LTM virtual cell quality can be determined (e.g., derived) from multiple LTM candidate cells. For example, it may be possible to avoid premature mobility outside the LTM area, such as due to (e.g., temporary) radio link quality issues in the serving cell, where other candidate cells within the LTM area would be acceptable. In other words, WTRU 102 can perform a process to identify whether it is worthwhile (e.g., efficient) to experience an L3 handover to cells outside the LTM (e.g., comparing the LTM set with cells outside the set using L3 filters) or to switch to a separate LTM set (e.g., comparing the LTM sets).

[0128] In some representative embodiments, the L3 cell quality of a virtual cell can be determined using beams from a subset or all cells of the LTM candidate set. Virtual cell quality derivation (e.g., a process) may refer to a modified cell quality derivation where beams from different cells within the LTM candidate set are considered to derive the virtual cell quality of the LTM candidate set. The virtual cell quality of the source LTM candidate set can be used as the quality of the source cell or as an offset to determine the quality to be applied to the source cell (e.g., on top of it). The virtual cell quality of the target LTM candidate set (e.g., a set of neighboring cells) can be used as the quality of the target cell or as an offset to determine the quality to be applied to the target cell (e.g., on top of it). WTRU 102 can use virtual cell quality to report measurement information, such as the time period (e.g., maximum or minimum) that has elapsed since (e.g., the last) LTM cell handover.

[0129] For example, WTRU 102 can perform averaging on a first (e.g., larger) set of cells and / or beams immediately after a cell handover, and later use a second (e.g., smaller) set of cells and / or beams, such as only the source cells or the best candidate cells. This ensures that WTRU 102 can eventually switch to a better LTM set.

[0130] In a first example embodiment, WTRU 102 may receive information indicating a configuration associated with determining (e.g., how to derive) the quality of the LTM set. The determined quality may take into account beams on all or a subset of the cells within the LTM set. For example, the configuration may include information indicating any of the following: the maximum / minimum number of cells to be included in the export; the maximum / minimum number of beams to be included in the export; the minimum quality of the beams / cells to be included in the export (e.g., absolute / relative to the serving cell, absolute / relative to the best cell); one or more average / filter weights to be applied to the export; one or more offset and / or scaling parameters to be applied to the export; a list of cells and / or beams that must be included in the export; a list of cells and / or beams that may not be included in the export; the association of each serving beam with a list of beams to be included on other cells in the virtual cell quality export; using the exported LTM set quality as an indication of the quality of the source and / or target cells; and / or using the exported LTM set quality as an indication of the offset to be applied to the quality of the source and / or target cells (e.g., on top of them).

[0131] WTRU 102 can receive information indicating the configuration for L1 and / or L3 measurement events. For example, the triggering conditions for an event may be based on a comparison of at least one LTM set quality (e.g., serving LTM set, target LTM set) with one or more of the following: another LTM set quality; individual cell quality (e.g., serving cell outside the LTM set, target cell outside the LTM set); cell quality threshold; maximum time since the last LTM cell handover; and / or minimum time since the last LTM cell handover.

[0132] WTRU 102 can determine the cells and / or beams to be considered for LTM set quality derivation (e.g., based on the above configuration for serving LTM set and / or target LTM set).

[0133] The WTRU 102 can perform measurements and derive the LTM set quality of the source LTM set and / or the target LTM set.

[0134] WTRU 102 can use (e.g., based on the configuration described above) the derived LTM set quality as the source cell quality and / or target cell quality. WTRU 102 can (e.g., based on the configuration described above) apply the derived LTM set quality to the serving and / or target cell quality (e.g., as offset, scaling factor, etc.).

[0135] WTRU 102 may determine that one or more triggering conditions of an event are met, such as a minimum time period having elapsed since the last LTM cell handover, and perform one or more of the following: send a measurement report associated with the event (e.g., including one or more derived LTM set quality, details of the derived cell and / or beam, and measurements of the legacy cell and / or beam); perform an associated conditional reconfiguration (e.g., if configured); and / or send instructions regarding the execution of the conditional reconfiguration (e.g., including one or more derived LTM set quality, details of the derived cell and / or beam, and measurements of the legacy cell and / or beam).

[0136] In some representative embodiments, the quality of the LTM serving cell can be modified by taking into account the quality of the LTM candidate cells. For example, it may be possible to avoid premature mobility outside the LTM area when most cells in the candidate LTM area have poor quality, or if the current LTM set has multiple active candidates. For the case of switching from one LTM set to another (e.g., inter-CU case), WTRU 102 may (e.g., should) verify that the target set has more than a single candidate and / or the source set does not have a sufficient (e.g., configured or predetermined number) number of active candidates.

[0137] In some representative embodiments, WTRU 102 may be configured with an active LTM set and a target LTM set. For example, cell quality derivation and / or comparison may be performed as a legacy process (e.g., deriving L3-filtered cell quality using N L1-filtered beam measurements of a cell) and modified with one or more additional triggering conditions that must be satisfied by a certain number of cells in the target and / or source candidate sets. The active LTM set may be determined as a set of LTM candidate cells on which WTRU 102 maintains downlink synchronization, has effective timing advance (e.g., UL synchronization), is actively reporting L1 CSI measurements, and is configured to perform TRS tracking, and / or candidate cells above a radio quality threshold. The target LTM set may be associated with a list of cell identities, PCIs, and / or SSBs. WTRU 102 may perform L1 and / or L3 measurements, as well as measurement reporting or CHO-triggered evaluations. The quality of the active LTM set can be determined by applying a first offset to the measured serving cell quality of any (e.g., each) additional LTM cells identified as being in the active LTM set. The quality of the target LTM set can be determined by applying a second offset to the measured neighbor cell quality of any (e.g., each) additional neighbor cells in the target set, such as those cells that meet the configured thresholds.

[0138] For example, WTRU 102 can send measurement reports or perform event-related CHOs, such as when any of the following are met: the target cell meets the event condition after applying one or more (e.g., second) offsets (e.g., event A4 on the target cell); the serving cell and the target cell meet the event conditions after applying one or more (e.g., first) offsets (e.g., event A3 comparing the source and the target, event A5 comparing the source and the target with different thresholds, etc.); the target cell meets the event condition after applying one or more (e.g., second) offsets (e.g., event A4 on the target cell, event A3 comparing the source and the target, event A5 comparing the source and the target with different thresholds, etc.). The target cells are compared with different thresholds (e.g., event A5, etc.) and a certain number of cells in the candidate set satisfy (e.g., the second) condition (e.g., the target cell satisfies event A3 / A4 / A5, and N cells in the target set satisfy the threshold); the target cells satisfy the event condition after applying one or more (e.g., the second) offsets and a certain number of cells in the source set satisfy (e.g., the second) condition (e.g., the target cell satisfies event A3 / A4 / A5, and N cells in the source set are below the second threshold, or fewer than N cells are determined to be in the LTM active set); and / or a certain number of target cells satisfy the event condition (e.g., N target cells satisfy event A3 / A4 / A5). The number of target cells and / or the number of cells in the LTM active set may depend on the elapsed time, such as the time elapsed since the last LTM cell handover (e.g., a first number if the elapsed time is less than the threshold, otherwise a second number).

[0139] In a second example embodiment, WTRU 102 may receive information indicating at least one configuration associated with (e.g., for identification) an active LTM set and / or a target LTM set. For example, the configuration for the LTM set may include information indicating any of the following: a list of cell identities, a list of PCIs, and / or a list of SSBs. The list may be associated with an active LTM set. The list may be associated with a target LTM set.

[0140] For example, WTRU 102 may receive information indicating at least one configuration for L1 and / or L3 measurement events. For example, the triggering conditions for the event may be based on criteria (or multiple criteria) (e.g., RSRP threshold) for determining suitable additional candidate cells (e.g., in addition to the target SpCell), the number of n additional candidates to be considered in the criteria, and / or a timer value for determining whether to use the n additional candidates.

[0141] For example, WTRU 102 can determine the number of additional candidates as a first value. WTRU can determine the first number of additional candidates (e.g., 0) based on the elapsed time, such as when the elapsed time since the last LTM cell handover is less than a configured threshold (e.g., a timer value), and otherwise determine it as a second value (e.g., n is greater than 0).

[0142] For example, WTRU 102 can perform measurements on active and target LTM sets. WTRU 102 can determine which cells to include in the active and target LTM sets based on any of the following: cells on which WTRU 102 maintains downlink synchronization; cells on which WTRU 102 has effective timing advance (e.g., UL synchronization); cells on which WTRU 102 actively reports L1 CSI beam measurements; cells on which WTRU 102 is configured to perform TRS tracking; and / or cells above a radio quality threshold.

[0143] For example, WTRU 102 may determine (e.g., a first) offset to be applied to any serving cell measurement based on cells in the active and / or target LTM set. WTRU 102 may also determine (e.g., a second) offset to be applied to any neighboring cell measurement based on cells in the target LTM set.

[0144] For example, WTRU 102 can evaluate measurement events based on serving cell measurements (e.g., after applying a first offset) and / or neighbor cell measurements (e.g., after applying a second offset). If the triggering conditions of an event are met, WTRU 102 can perform any of the following: send a measurement report associated with the event (e.g., including information indicating the identifiers of any additional cells considered in the event and / or the primary cell that triggered the event); and / or perform an associated conditional reconfiguration, if configured; and / or send information indicating the execution of the conditional reconfiguration (e.g., including information indicating the identifiers of any additional cells considered in the event and / or the primary cell that triggered the event).

[0145] In some representative embodiments, long-term measurement assessments can be performed across multiple LTM serving cells. For example, the network may want to configure relatively long trigger time-to-trigger (TTT) values ​​for one or more L3 measurement events to prevent premature handover out of the LTM set. Side effects may include WTRU 102 using LTM to handover frequently between cells (e.g., more frequently than per TTT), and / or L3 measurement events may trigger too late (or never trigger) due to changes in the serving cell of WTRU 102 within the TTT. Triggering conditions can be enhanced to allow consideration of all serving cells within the TTT, such as when a candidate cell is significantly better than the current serving cell.

[0146] For example, when WTRU 102 uses LTM to handover from a first serving cell to a second serving cell, WTRU 102 can derive L3 cell quality and evaluate L3 event triggering based on measurements applicable to both the first and second serving cells (e.g., as if the serving cell were a single serving cell). WTRU 102 can continue (e.g., currently) the evaluation of serving cell quality and measurement event triggering after the cell change. After the cell change, WTRU 102 can (e.g., continue) use previous (one or more) serving cell measurements as if they were current cell measurements. WTRU 102 can trigger a measurement report where at least one condition is met for the current serving cell over the TTT duration (e.g., evaluated using the first and second serving cells). WTRU 102 can perform the aforementioned operations if the measurement results for a candidate cell are above a threshold; otherwise, WTRU 102 can trigger (e.g., only) if the condition is met over the TTT for the current serving cell. For example, the L3 filtering result for the second serving cell can be based on the L3 filtering result for the first serving cell during cell handover.

[0147] In a third example embodiment, the WTRU may receive information indicating a configuration associated with determining (e.g., how to derive) the quality of the serving cell using L3 filtering by acquiring L1 RSRP, RSRQ, and / or SINR samples from any cell that is already within the filtering window (Pcell). For example, this configuration may include information indicating at least one of filter coefficients, RS type, and / or RS index.

[0148] For example, WTRU 102 can receive information indicating the configuration for L1 and / or L3 measurement events. The configuration may include information indicating that the evaluation on TTT (e.g., time period, duration, interval) is performed using thresholds of measurement results from any cell that is already a serving cell and / or neighboring cell measurement results while the TTT is running (e.g., during the TTT).

[0149] For example, WTRU 102 can determine the conditions for an event to be met for the first serving cell and neighboring cells within a first time period. The first time period can be less than (e.g., shorter than) TTT.

[0150] For example, WTRU 102 can receive information indicating a handover from the first serving cell to the second serving cell using LTM at the end of the first time period (or no later than the first time period).

[0151] For example, WTRU 102 can determine the conditions for events to be met for the second serving cell and neighboring cells during a second time period. The sum of the first and second time periods can be equal to or greater than TTT. If the result of the neighboring cell is higher than the result of the second serving cell plus a threshold, WTRU 102 can trigger the transmission of a measurement report including information indicating the first and / or second serving cells and / or the first and / or second time periods.

[0152] In some representative embodiments, a timer for LTM measurement reports can be disabled after the L3 handover process. For example, a timer on L1 reports can be disabled (e.g., temporarily) to limit reporting after an L3 cell handover. The example disabling described herein can resolve race conditions where an L3 handover is completed but an LTM handover occurs before L3 signaling (e.g., an RRC reconfiguration completion transmission using RLC AM) is completed. This can occur for L3 handovers that include the set of LTMs in the target configuration, or it can occur during the initial LTM setup (e.g., an LTM cell handover occurs before the delivery of an RRC reconfiguration completion corresponding to the LTM setup is completed).

[0153] To provide RRC reconfiguration completion signaling for successful delivery (e.g., to the CU) after an L3 handover, WTRU 102 can be prevented from sending L1 measurement reports and / or performing LTM. Sending L1 measurement reports and / or performing LTM may result in LTM handover triggered by the DU and loss of L3 signaling, causing the CU to detect a handover failure or reconfiguration failure. For example, temporary restrictions on L1 reporting to neighbors and / or candidate cells (e.g., current cell beam reporting is still enabled to allow scheduling) can be implemented using a timer or by waiting for RLC acknowledgment of the RRC message (e.g., completion) transmission. For example, WTRU 102 can be made to complete L3 measurement assessments, such as when preventing LTM from occurring before the TTT period has passed (e.g., TTT is in progress).

[0154] In the fourth example embodiment, WTRU 102 may receive an RRC reconfiguration message that includes information indicating an LTM measurement pause and / or associated timer values.

[0155] For example, WTRU 102 can perform RRC reconfiguration and can stop LTM L1 measurement reporting for neighboring cells (e.g., if it is already running). WTRU 102 can send an RRC reconfiguration complete message.

[0156] For example, if the elapsed time since receiving the RRC reconfiguration is less than the indicated time (e.g., a timer value) and WTRU 102 receives an LTM cell handover command, WTRU 102 may transmit an indication not to perform a cell handover (e.g., via MAC CE). If an LTM cell handover is received before the timer expires (e.g., the elapsed time is less than the indicated time), WTRU 102 may not perform the LTM cell handover command and may respond with a failure indication.

[0157] For example, if the elapsed time since the transmission or successful acknowledgment of the RRC reconfiguration completion message is less than the indicated time (e.g., a timer value) and WTRU 102 receives an LTM cell handover command, WTRU 102 may (e.g., via MAC CE) transmit an indication that a cell handover was not performed. If an LTM cell handover is received before the timer expires (e.g., the elapsed time is less than the indicated time), WTRU 102 may not perform the LTM cell handover command and may respond with a failure indication.

[0158] For example, when a period of time corresponding to the indicated timer value has elapsed since the RRC reconfiguration message was received, the WTRU 102 can start (or resume) the LTM L1 measurement report for the candidate cell.

[0159] For example, when a period of time corresponding to the indicated timer value has elapsed since the transmission of the RRC reconfiguration complete message, the WTRU 102 can start (or resume) the LTM L1 measurement report for the candidate cell.

[0160] In some representative embodiments, when an RRC message is generated while LTM is in use, the WTRU can provide the network with the identifier of the PCell in use. For the UL case, a race condition can be resolved where an L3 measurement report is triggered, but an LTM handover occurs before the RRC message is transmitted. This could cause the L3 measurement report to be transmitted to the wrong cell (e.g., not the cell on which the event is configured). If the same measurement configuration (e.g., ID) is configured on the target cell, there may be ambiguity regarding on which cell the event was triggered. For the DL case, a race condition can be resolved where an RRC reconfiguration message is transmitted by the CU, but the DU performs LTM. If the RRC message does not contain a configuration specific to the old cell group served by the first DU (e.g., DU#1), the CU can safely retransmit the RRC message to the WTRU 102 via the second DU (e.g., DU#2). Problems may occur if the content of the RRC message has an outdated configuration associated with the old serving cell group on the first DU. If RRC messages are retransmitted to WTRU 102 via the second DU, WTRU 102 may fail to apply outdated RRC configurations because it references the old serving cell group and WTRU 102 is connected to the new serving cell group. This could trigger a connection re-establishment for WTRU 102. If RRC messages are not retransmitted to WTRU 102 via the second DU, any new RRC messages from the same SRB will have to use a new PDCP sequence number (SN), as mandated for replay protection using the same AS security context. This could create PDCP SN gaps. Since the default value of the t-reordering timer for SRB1 is infinity, the t-reordering timer may never expire, and the SRB's PDCP SDU may become undeliverable to the upper layer.

[0161] In some representative embodiments, information indicating the PCell ID can be included in the UL RRC message corresponding to the PCell when the corresponding event (e.g., a measurement event, RRC reconfiguration) is triggered. For example, an RRC reconfiguration can be triggered, and the RRC reconfiguration completion message can include information indicating whether an RRC reconfiguration and / or L2-triggered reconfiguration has occurred.

[0162] In the fifth example embodiment, WTRU 102 can receive information indicating L3 measurement events and / or reporting configurations. WTRU 102 can receive information indicating LTM configurations. WTRU 102 can receive information indicating configurations for including current PCell information in the L3 measurement report (e.g., any candidate cell with or without an added offset, whose measurement results in the latest L1 and / or L2 reports are higher than those of the serving cell). WTRU 102 can perform measurement evaluations on the current cell and transmit L1 and / or L2 measurement reports. WTRU 102 can determine the trigger for transmitting L3 measurement reports based on the L3 measurement configuration. If the L1 and / or L2 measurement reports indicate that the measurement results of a candidate cell are higher than those of the serving cell (e.g., with an offset), WTRU 102 can transmit an L3 measurement report including information indicating the current PCell. WTRU 102 can receive LTM cell handover commands and complete RRC transmissions on the new cell.

[0163] In the sixth example embodiment, WTRU 102 may receive an RRC reconfiguration message in the source cell. WTRU 102 may apply the RRC reconfiguration and transmit an RRC reconfiguration complete message (e.g., before LTM). The RRC reconfiguration complete message may include information indicating that the RRC reconfiguration was completed due to the application of RRC reconfiguration (e.g., only) and information indicating the source cell (e.g., PCI).

[0164] In the seventh example embodiment, WTRU 102 may receive an RRC reconfiguration message in the source cell. WTRU 102 may apply the RRC reconfiguration. WTRU 102 may receive (or determine) an LTM trigger and reconfigure to the new cell. WTRU 102 may transmit an RRC reconfiguration complete message, which includes information indicating that the RRC reconfiguration was completed due to the application of RRC reconfiguration and LTM reconfiguration, and information indicating the source cell (e.g., PCI).

[0165] For example, LTM-only reconfiguration can cause WTRU 102 to send an RRC reconfiguration complete message that does not include any indication (e.g., the source cell's PCI). As another example, the RRC reconfiguration complete message may include information indicating that the message was sent because LTM-only reconfiguration was applied.

[0166] General terms As used in this article, to execute LTM or to perform an LTM process can refer to executing... Figure 4Any or all of the steps described herein. For example, WTRU 102 may perform LTM, which includes early synchronization with one or more candidate cells in the DL and / or UL, performing L1 measurements and reporting on one or more candidate cells, and handover between candidate cells (e.g., performing a handover). As another example, WTRU 102 may perform LTM, which refers to WTRU 102 moving and / or handover between multiple candidate cells during the process.

[0167] As used herein, a candidate cell set can refer to a group of RRC configurations corresponding to HO configurations for one or more candidate SpCells and / or SCells. One or more candidate cell sets can be a group of more than one RRC configuration corresponding to HO configurations for one or more candidate SpCells and / or SCells. For example, a candidate cell set may include one or more complete RRC reconfiguration messages, one or more cell group configurations, and / or one or more cell configurations, and / or interchangeably thereof. Candidate cell configurations may include candidate configuration identifiers, and / or candidate cell groups may include candidate cell group identifiers. For example, RRC signaling can be used to group candidate cells. Switching between different sets of candidate cells may include updating the serving cell index or candidate configuration index used in L1 and MAC signaling to reference a specific index. As an example, a MAC CE that triggers a reconfiguration may include informing WTRU 102 which cell's candidate configuration index to perform the reconfiguration to.

[0168] In some representative embodiments, RRC can be used to configure one or more candidate cell groups as a single list or group of candidate cell configurations. Grouping can occur during the early synchronization or LTM execution phase (e.g., rather than the configuration phase). With respect to the RRC configuration list or group, the set of candidate cells can be considered a single group, and the cells selected for performing early synchronization, L1 measurements, and LTM execution can depend on further grouping into multiple subsets of the entire candidate cell list. In other words, the grouping itself may not be modeled using candidate configuration identifiers at the RRC, but the grouping can be performed as part of the early synchronization or LTM execution process.

[0169] As used herein, LTM candidate configuration can refer to any type of pre-configured cell information. For example, WTRU 102 can be configured with one or more conditional reconfigurations [such as conditional handover (CHO), conditional PSCell addition (CPA), and / or conditional PSCell change (CPC), which are effective before and / or after a cell change, or in certain cells].

[0170] General principles and observation L1 measurement As used herein, L1 measurement may refer to a measurement of any one of RSRP, RSRQ, RSSI, and / or similar values. L1 measurements may be performed by the WTRU 102 on any one of the cells, beams, cell sets, and / or beam sets. L1 measurements may be similar to L3 measurements reported in the RRM, with differences in filtering, the reference signal for the measurement, and the reporting mechanism.

[0171] In some representative examples, including but not limited to the context of 3GPP standards, L1 measurements can refer to... Figure 2 Points A and A in 1 Related measurements.

[0172] L3 measurement As used herein, L3 measurement can refer to the measurement after processing in the L3 filter. In some representative examples, including but not limited to the context of 3GPP standards, L3 measurement can refer to a beam-specific measurement (reported to Layer 3 after beam combining / selection). Figure 2 Measurement at point B (e.g., cell quality measurement) or Figure 2 The measurement at point C (e.g., the measurement after processing in the Layer 3 filter). For example, the reporting rate at C may be more or less the same as (e.g., identical) the reporting rate at point B. The L3 measurement can be used as input to one or more evaluations of the reporting criteria. General Measurement As used herein, L1 measurement can refer to L1 measurement relative to LTM, and L3 measurement can refer to measurement performed in RRC using specified L3 filtering and cell quality derivation. Some representative embodiments can be applied to L1 measurements and / or RRM / L3 measurements, as well as other measurements (e.g., measurements of speed, location, altitude, flow, etc.) or measurements obtained after alternative processing (e.g., different types of filtering or different types of averaging) or different measurements (e.g., RSRP, RSRQ, RSSI, CSI, etc.).

[0173] Measuring events As used herein, a measurement event can refer to the occurrence of a measurement meeting certain conditions. Some representative embodiments may include measurement events as set forth in 3GPP TS 38.331 §5.5.4, including event A1 (service becomes better than a threshold); event A2 (service becomes worse than a threshold); event A3 (neighbor becomes better than SpCell offset); event A4 (neighbor becomes better than a threshold); event A5 (SpCell becomes worse than threshold 1 and neighbor becomes better than threshold 2); and so on, as is known to those skilled in the art. Measurement events as described herein include, but are not limited to, the aforementioned events.

[0174] Common benefits In some representative embodiments, multiple types of mobility, measurement, and reporting can coexist. For example, WTRU 102 can execute L1 / 2-triggered mobility procedures and L3-triggered mobility procedures. Due to the nature of the procedures, race conditions may exist due to different measurement timings, different signaling delays, different network nodes controlling mobility, and / or different protocol layers handling the processing in WTRU 102 and the network. Therefore, the embodiments disclosed herein can enable interaction between different mobility types and / or provide measures to reduce or eliminate potential problems that may arise due to race conditions between procedures.

[0175] LTM and Measurement Configuration In some representative embodiments, LTM configuration may include RRC pre-configuration for multiple serving cells and / or configuration of L1 measurements (e.g., CSI reporting, L1 event triggering) used with LTM. For example, WTRU 102 may be configured with L3 measurements for measurement reporting and / or conditional reconfiguration (CHO).

[0176] In some representative embodiments, WTRU 102 may be configured to associate L1 measurements with L3 measurements. For example, WTRU 102 may be configured to indicate which L1 measurement results can affect L3 measurement results. For example, in some cases, specific measurement objects, measurement identifiers, and / or conditional reconfiguration may use specific CSI measurement reports and / or resource configurations.

[0177] ability In some representative embodiments, WTRU 102 may report capability information for specific functions (e.g., WTRU-specific capabilities), such as support for LTM, support for specific measurement derivation methods, and / or the maximum number of beams, cells, and / or carriers that can be measured using any specific measurement method. For example, capability information may include performance indicators such as the number of RF receivers, maximum bandwidth, processing capacity, and / or timing information. LTM and / or measurement capabilities may be reported per frequency band or in combination per frequency band.

[0178] LTM virtual cell quality derived from beams from multiple LTM candidate cells In some representative embodiments, WTRU 102 can avoid premature mobility outside the LTM area, such as when there is a temporary radio link quality problem in the serving cell and other candidate cells within the LTM area would be acceptable. For example, WTRU 102 can identify whether it is worthwhile to perform an L3 handover to a cell outside the LTM area, such as by comparing the LTM set with cells outside the set using L3 filters, or by performing a handover to a separate LTM set (e.g., comparing the LTM sets).

[0179] In some representative embodiments, L3 cell quality can be determined (e.g., derived) for a “virtual cell.” The L3 cell quality of a virtual cell can utilize beams from a subset or all cells of the LTM candidate set. For example, virtual cell quality derivation can refer to a modified cell quality derivation, such as where beams from different cells in the LTM candidate set can be considered to derive the virtual cell quality of the LTM candidate set. For example, the virtual cell quality of a source LTM candidate set can be used as the quality of the source cell or to determine an offset to be applied (e.g., on top of the quality of the source cell). For example, the virtual cell quality of a target LTM candidate set can be used as the quality of the target cell or to determine an offset to be applied (e.g., on top of the quality of the target cell). For example, WTRU 102 can use virtual cell quality to report measurement information, such as the condition that the maximum or minimum time period has elapsed since the last LTM cell handover. In some representative embodiments, WTRU 102 may perform filtering (e.g., averaging) on ​​a larger set of cells and / or beams for a first time period after cell handover, and use a smaller set of cells and / or beams (e.g., only the source cell or the best candidate cell) for a second time period (e.g., after the first time period), such as to ensure that WTRU 102 can eventually switch to a better set of LTMs.

[0180] In some representative embodiments, WTRU 102 may receive information indicating a configuration associated with determining (e.g., how to derive) the quality of the LTM set. The determined quality may take into account beams on all or a subset of the cells within the LTM set. For example, the configuration may include information indicating any of the following: the maximum / minimum number of cells to be included in the export; the maximum / minimum number of beams to be included in the export; the minimum quality of the beams / cells to be included in the export (e.g., absolute / relative to the serving cell, absolute / relative to the best cell); one or more average / filter weights to be applied to the export; one or more offset and / or scaling parameters to be applied to the export; a list of cells and / or beams that must be included in the export; a list of cells and / or beams that may not be included in the export; the association of each serving beam with a list of beams to be included on other cells in the virtual cell quality export; an indication of the quality of the source and / or target cells using the exported LTM set quality; and / or an indication of the offset to be applied to the quality of the source and / or target cells (e.g., on top of them) using the exported LTM set quality.

[0181] WTRU 102 can receive information indicating the configuration for L1 and / or L3 measurement events. For example, the triggering conditions for an event may be based on a comparison of at least one LTM set quality (e.g., serving LTM set, target LTM set) with one or more of the following: another LTM set quality; individual cell quality (e.g., serving cell outside the LTM set, target cell outside the LTM set); cell quality threshold; maximum time since the last LTM cell handover; and / or minimum time since the last LTM cell handover.

[0182] WTRU 102 can determine the cells and / or beams to be considered for LTM set quality derivation (e.g., based on the above configuration for serving LTM set and / or target LTM set).

[0183] The WTRU 102 can perform measurements and derive the LTM set quality of the source LTM set and / or the target LTM set.

[0184] WTRU 102 can use (e.g., based on the configuration described above) the derived LTM set quality as the source and / or target cell quality. WTRU 102 can (e.g., based on the configuration described above) apply the derived LTM set quality to the serving and / or target cell quality (e.g., as offset, scaling factor, etc.).

[0185] WTRU 102 may determine that one or more triggering conditions of an event are met, such as a minimum time period having elapsed since the last LTM cell handover, and perform one or more of the following: send a measurement report associated with the event (e.g., including one or more derived LTM set quality, details of the derived cell and / or beam, and measurements of the legacy cell and / or beam); perform an associated conditional reconfiguration (e.g., if configured); and / or send instructions regarding the execution of the conditional reconfiguration (e.g., including one or more derived LTM set quality, details of the derived cell and / or beam, and measurements of the legacy cell and / or beam).

[0186] Figure 6 This is a system diagram illustrating an example of a virtual cell 602. For example, virtual cell and / or virtual cell quality can be used interchangeably with LTM set quality. For example, WTRU 102 can be configured with more than one candidate LTM cell, such as cell 1 (e.g., PCI 1) 604 and cell 2 (e.g., PCI 2) 606. For each candidate LTM cell, WTRU 102 can be configured with one or more beams (e.g., SSB or CSI-RS resources) 608 to perform measurements. WTRU 102 can be configured to derive cell quality based on beam combining and L3 filtering performed on L1 beam measurements performed on one or more beams 608 of the same cell (e.g., with the same PCI). This can be advantageous for L3 handover because cell quality can consider multiple beams on the same cell, thus allowing WTRU 102 to evaluate measurement events and report them to the gNB, thereby allowing the gNB to make a decision on whether to perform a handover from one cell to another. Using LTM, the WTRU 102 can be configured with multiple candidate cells and can be configured to maintain uplink and / or downlink synchronization with multiple candidate cells, and can be triggered to perform handovers from one cell to another, such as an incomplete MAC reset. These enhancements take into account significantly improved latency for cell handovers with less overhead, and therefore it can be anticipated that performing cell handovers between cells within a configured LTM set (e.g., belonging to the same DU or the same CU / gNB) may be preferred relative to changes in the CU and / or gNB. This improved mobility between cells configured as LTM candidate cells takes into account that cells belonging to this configuration set are considered groups or sets. In some locations, such as near the boundary between two configured LTM candidates, the WTRU 102 may be able to measure multiple beams from multiple cells. For example, the WTRU 102 may be able to measure six good beams, such as... Figure 6 As shown (for example, three beams 608 from cell 1 604 and three beams 608 from cell 2 606, as...) Figure 6(As shown in the diagram). When evaluating L3 measurement conditions to compare the LTM set quality with another cell or another LTM set, it may be preferable to consider all six beams together. In one example, a cell outside the configured LTM set may have an individual cell quality higher than that of cell 1 604 or cell 2 606 (e.g., based on the number of beams from that cell). When the LTM set quality considers all six good beams from both cell 1 604 and cell 2 606, in which WTRU 102 can switch, the overall quality of the virtual cell 602 may be better than that of cells outside the LTM candidate set. The LTM set quality can be derived based on more than one cell to determine whether it is better to remain in the current LTM configuration using an L1 / 2-based mobility procedure, or whether to perform an L3 reconfiguration for cells or LTM sets outside the current LTM configuration.

[0187] As used herein, the terms virtual cell and LTM ensemble quality are used interchangeably and can refer to the radio quality of an ensemble of cells derived from individual beam measurement quality from beams from more than one cell in the ensemble. For example, virtual cell can refer to a cell quality derived such as an RSRP (e.g., L1 RSRP) similar to that defined in 3GPP TS 38.331 §5.5.3.3 based on individual beam measurements from multiple cells (e.g., rather than deriving cell measurement results by measuring one or more beams associated with each cell configured by the network, as specified in 3GPP TS 38.331 §5.5.3.1).

[0188] Figure 7 This is a process diagram illustrating an example process for measuring and reporting virtual cell information. Figure 7At position 702, WTRU 102 can receive information indicating the configuration associated with the LTM candidate set. This configuration may include information about how the quality of the LTM candidate set is derived, and this quality may take into account the beams on all or a subset of the cells within the candidate set. For example, the configuration may include any of the following: the maximum and / or minimum number of cells to be included in the export; the maximum and / or minimum number of beams to be included in the export; the maximum and / or minimum number of beams to be included in each cell in the export or the exact number of beams to be included in the export; the minimum quality of the beams and / or cells to be included in the export (e.g., absolute or relative to the serving cell, absolute or relative to the best cell); the average and / or filtering weights to be applied to perform the export; the offset and / or scaling to be applied to the quality export; a list of cells and / or beams that may (e.g., must) be included in the export; a list of cells / beams that may not be included in the export; a list of beams to be included on other cells in the virtual cell quality export associated with any (e.g., each) serving beam; and / or an indication of whether the exported LTM set quality is used as the quality of the source or target cell and / or as an indication of the offset to be applied to the quality of the source or target cell (e.g., on top of it).

[0189] For example, WTRU 102 can be configured with a maximum number of cells within the LTM set to be considered in the LTM set quality derivation. As an example, WTRU 102 can be configured to include beams from no more than N cells in the cell quality. WTRU 102 can select N cells with the beam having the highest L1 measurement (e.g., RSRP). For example, WTRU 102 can also be configured with a minimum number of cells. As an example, if beams from fewer than N cells meet a minimum quality threshold (e.g., ...), ... absThreshSS-BlocksConsolidation If a standard such as a standard cell quality standard is used, then WTRU 102 can (e.g., should) use a standard or normal cell quality export. For example, WTRU 102 can be configured with a specific number of cells to be included in the export.

[0190] For example, the WTRU 102 can be configured with a maximum number of beams within the LTM ensemble to be considered in the LTM ensemble quality export. As an example, the WTRU 102 can be configured to include no more than N beams in the cell quality export (e.g., using...). nrofSS-BlocksToAverage For example, the WTRU 102 can be configured with a minimum number of beams. As an example, if fewer than N beams meet one or more criteria, such as a minimum quality threshold (e.g., ...), absThreshSS- BlocksConsolidationIf so, the WTRU 102 can (e.g., should) use standard or normal cell quality export. As another example, the WTRU 102 can be configured with a specific number of beams to be included in the export.

[0191] For example, the WTRU 102 can be configured with a maximum and / or minimum number of beams per cell to be included in the output. For example, the WTRU 102 can be configured with a specific number of beams to be included in the output.

[0192] For example, WTRU 102 can be configured with minimum beam and / or cell quality to be included in the output (e.g., absolute / relative to the serving cell, absolute / relative to the best cell). As an example, WTRU 102 can be configured with an absolute threshold (e.g., absThreshSS-BlocksConsolidation As an example, the WTRU 102 can be configured with relative thresholds, such as thresholds that allow a beam or cell to be included within X dB of the serving cell (PCell) or within X dB of the best cell or best beam.

[0193] For example, WTRU 102 can be configured to derive each cell measurement based on the SS / PBCH block to a higher value than... absThreshSS-BlocksConsolidation The linear power scale averaging of the highest beam measurement values, such as where the total number of averaged beams can (e.g., should) not exceed nrofSS-BlocksToAverage As another example, the WTRU 102 can be configured with weights to be applied to each beam measurement. The beam with the highest beam measurement can carry the most weights, and other beams can have fewer weights when performing averaging.

[0194] For example, LTM ensemble quality can be derived by including an offset in the optimal beam measurement. For instance, the optimal beam might have an RSRP of X dBm. An offset can be added to the beam measurement of each additional beam that satisfies one or more criteria (e.g., a minimum threshold). As another example, the optimal beam measurement can use a scaling factor based on the number of other beams that satisfy one or more criteria.

[0195] For example, WTRU 102 can be configured with a list of cells and / or beams that can (e.g., must) be included in the export. For example, WTRU 102 can be configured with a list of cells and / or beams that can (e.g., should) not be included in the export. In this example, WTRU 102 can be configured with one or more specific cells and / or beams to include in or exclude from the LTM set quality export.

[0196] For example, the WTRU 102 can be configured with a list of cells and / or beams and / or optimal beams for each Pcell to use in the export. For example, for a given current Pcell, or for any given serving beam, or for any optimal beam, a list of other beams can be provided to the WTRU 102 for measurement and inclusion in the LTM set export.

[0197] For example, WTRU 102 can be configured with instructions regarding the method of LTM ensemble quality deriving. As an example, the instructions can configure WTRU 102 to perform LTM ensemble quality deriving based on beam averaging from multiple cells, or to derive LTM ensemble quality based on adding an offset to the cell quality deriving, as described herein.

[0198] For example, WTRU 102 can be configured with a list of cells and / or beams that can be dynamically updated by the gNB. For instance, the gNB can configure the list of cells and / or beams using one or more methods described herein. An indication of a subset of cells and / or beams can then be provided to WTRU 102 (e.g., control signaling such as in MAC CE). In one example, cells and / or beams can be determined from the cells and / or beams used for L1 measurements (e.g., the same set of cells / beams can be used).

[0199] exist Figure 7 At 704, WTRU 102 may receive information indicating the configuration for L1 or L3 measurement events, wherein the triggering condition of the event may be based on a comparison of at least one LTM set quality (e.g., serving LTM candidate set, target LTM candidate set) with one or more of the following: another LTM set quality; individual cell quality; cell quality threshold; maximum time since the last LTM cell handover; and / or minimum time since the last LTM cell handover.

[0200] For example, WTRU 102 can compare the serving and / or current LTM set with a potential target set. The current set may include cells and / or beams for which WTRU 102 (e.g., LTM candidate configurations) have already been configured, while the target set may be a list of cells and / or measurement resources with indications of these forming sets. For example, WTRU 102 may be configured to evaluate normal measurement events (e.g., as specified in 3GPP TS 38.331 §5.5.4). The quality of the current and target derived LTM sets can be used as measurement results for the serving cells (e.g., Ms) and for neighboring cells (e.g., Mn). For example, the quality of the current LTM set can be used as measurement results for the serving cells. For example, the quality of the target LTM set can be used as measurement results for neighboring cells.

[0201] For example, WTRU 102 can be configured with individual cell quality (e.g., serving cell outside the LTM set, target cell outside the LTM set). As an example, WTRU 102 can be configured to evaluate normal measurement events (e.g., event A3, a neighbor becomes offset better than SpCell, as specified in 3GPP TS 38.331 §5.5.4). LTM set quality can be used as the measurement result of the serving cell (e.g., Ms), while the normal cell quality of the neighboring cell can be used as the measurement result of the neighboring cell (e.g., Mn).

[0202] For example, WTRU 102 can be configured with a cell quality threshold. WTRU 102 can compare the current or target LTM set quality with an absolute threshold. As an example, WTRU 102 can be configured with measurement events (e.g., event A1, service becomes better than the threshold, or event A2, service becomes worse than the threshold), and the resulting LTM set quality can be used as a measurement result for the serving cell (e.g., Ms). As an example, WTRU 102 can be configured with measurement events (e.g., event A4, a neighbor becomes better than the threshold), and the resulting LTM set quality can be used as a measurement result for the neighboring cell (e.g., Mn). As an example, WTRU 102 can be configured with measurement events (e.g., event A5, SpCell becomes worse than threshold 1, and a neighbor becomes better than threshold 2), where the current and target derived LTM set quality can be used as derived measurements for the serving cell (e.g., Ms) and the neighboring cell (e.g., Mn).

[0203] For example, WTRU 102 can be configured with a maximum time period since the last LTM cell handover. As an example, WTRU 102 can be configured to perform evaluations using LTM set quality up to the maximum amount of time since the last LTM cell handover. This can be used, for example, to configure WTRU 102 to use LTM set quality when SpCell changes frequently due to LTM (e.g., because WTRU 102 is mobile), and to use serving cell quality when WTRU 102 becomes stationary.

[0204] For example, WTRU 102 can be configured with a minimum time period since the last LTM cell handover. As an example, WTRU 102 can be configured to use LTM set quality only (e.g., only) after a certain time has elapsed since the last LTM cell handover. This can be used, for example, to configure WTRU 102 to use LTM set quality only after WTRU 102 has had sufficient time to begin early synchronization of the target candidate cell following the LTM cell handover.

[0205] exist Figure 7At point 706, WTRU 102 can determine, based on the above configuration (e.g., for serving LTM sets and / or target LTM sets), which cells and / or beams to consider for LTM set quality export. Using the configuration received in 1. and / or 2., WTRU 102 can select which cells to consider in the LTM set export. For example, this selection can depend on any of the following: the current SpCell and / or Pcell; an explicit list of cells and / or beams; and / or the current measurement configuration (e.g., CSI resource configuration).

[0206] exist Figure 7 At point 708, WTRU 102 can perform measurements and derive the LTM set quality of the source and / or target LTM sets. For example, WTRU 102 can perform measurements based on the above configuration according to any configured RRM and / or CSI resources (e.g., SSB, CSI-RS). Based on L1 beam measurements (e.g., for cell measurements, the network can configure any of RSRP, RSRQ, SINR, RSCP, and / or EcN0 as trigger quantities), WTRU 102 can select which measurement beams will be included in the LTM set quality derive. For example, WTRU 102 can perform a selection of any of the following: the best N beams, the best L beams per cell, up to the N best beams that have been configured to be included for a certain best beam and / or cell, any particular beam (e.g., regardless of its quality), any beam above a certain absolute threshold, or any beam within a relative threshold (e.g., compared to the best beam or SpCell).

[0207] Based on the beams already selected for inclusion in the LTM ensemble quality derive by the WTRU 102, the WTRU 102 can derive quality values. For example, LTM ensemble measurements can be based on one or more SS / PBCH blocks, as above a threshold (e.g., absThreshSS-BlocksConsolidation The average of the (e.g., highest) beam measurements is a linear power scale average. For example, the total number of averaged beams may (e.g., should) not exceed a threshold (e.g., nrofSS-BlocksToAverage Example beam measurements are described in 3GPP TS 38.215.

[0208] For example, WTRU 102 can be used, but is not limited to, in... Figure 7 Any averaging method or parameter described in the configuration at position 702.

[0209] exist Figure 7At position 710, WTRU 102 can use the exported LTM set quality as the source and / or target cell quality based on this configuration. As an example, WTRU 102 can add the exported LTM set quality on top of the serving and / or target cell quality.

[0210] For example, for any measurement event described in 3GPP TS 38.331 §5.5.4, WTRU 102 can use the current LTM set quality instead of the serving cell quality (e.g., Ms).

[0211] For example, for any measurement event described in 3GPP TS 38.331 §5.5.4, WTRU 102 can use the target LTM set quality instead of the neighbor cell quality (e.g., Mn).

[0212] For example, WTRU 102 can use any of a variety of comparisons or evaluations to compare the derived current and / or target LTM set quality with another LTM set quality and / or cell quality.

[0213] exist Figure 7 At position 712, WTRU 102 can determine whether the triggering conditions of the evaluated event are met.

[0214] exist Figure 7 At position 714, WTRU 102 can determine whether a minimum time period (e.g., T1) has elapsed since the last LTM cell handover.

[0215] exist Figure 7At point 716, when the triggering conditions of the evaluated event are met, and when a minimum time period (e.g., T1) has elapsed since the last LTM cell handover and / or a maximum time period (e.g., T2) has not elapsed since the last LTM cell handover, WTRU 102 may perform any of the following. For example, if WTRU 102 has been configured with RRC measurement events, objects, or reports, WTRU 102 may send a measurement report associated with that event. As an example, WTRU 102 may include (e.g., in the measurement report) information indicating any of the following: the quality of the derived LTM set, details of the specific cell and / or beam used for the derived data (e.g., beam ID and / or cell ID), and / or general cell and / or beam measurement results for the LTM set and / or neighboring cells. For example, if configured, WTRU 102 may perform an associated conditional reconfiguration. As an example, in a reconfiguration completion message or a subsequent message, WTRU 102 may include information indicating the execution of a conditional reconfiguration, which may include any one of the following: the quality of the exported LTM set, details of the specific cell and / or beam used for the exported LTM set (e.g., beam ID and / or cell ID), and / or general cell and / or beam measurement results for the LTM set and / or neighboring cells.

[0216] In some representative embodiments, L1 signaling (e.g., PUCCH and / or PUSCH) can be used to report LTM cell quality (e.g., to the serving cell). For example, WTRU 102 reporting can be periodic or aperiodic (e.g., triggered by the serving cell).

[0217] LTM serving cell quality modified using LTM candidate cell quality To avoid premature mobility outside the LTM area when some (e.g., most) cells in the candidate LTM area have poor quality or when the current LTM set has multiple active candidates, the LTM serving cell quality can be modified based on the quality of the LTM candidate cells. For a switch from one LTM set to another (e.g., an inter-CU situation), WTRU 102 can (e.g., should) verify that the target set has more candidates than a single candidate and that the source set does not have enough active candidates.

[0218] In some representative embodiments, WTRU 102 may be configured with an active LTM set and a target LTM set. For example, cell quality derivation and / or comparison may be performed as a legacy process (e.g., deriving L3-filtered cell quality using N L1-filtered beam measurements of a cell) and modified with one or more additional triggering conditions that must be satisfied by a certain number of cells in the target and / or source candidate sets. The active LTM set may be determined as a set of configured LTM candidate cells on which any of the following are satisfied: WTRU 102 is maintaining downlink synchronization; WTRU 102 has effective timing advance (e.g., UL synchronization); WTRU 102 is actively reporting L1 CSI measurements; WTRU 102 is configured to perform TRS tracking; and / or candidate cells above a radio quality threshold. The target LTM set may be associated with a list of cell identities, PCIs, and / or SSBs. WTRU 102 may perform L1 and / or L3 measurements, as well as measurement reporting or CHO-triggered evaluations. The quality of the active LTM set can be determined by applying a first offset to the measured serving cell quality of any (e.g., each) additional LTM cells identified as being in the active LTM set. The quality of the target LTM set can be determined by applying a second offset to the measured neighbor cell quality of any (e.g., each) additional neighbor cells in the target set, such as those cells that meet the configured thresholds.

[0219] For example, WTRU 102 can send measurement reports or perform event-related CHOs, such as when any of the following are met: the target cell meets the event condition (e.g., event A4 on the target cell) after applying one or more (e.g., second) offsets; the serving cell and the target cell meet the event condition (e.g., event A3 comparing source and target, event A5 comparing source and target with different thresholds, etc.) after applying one or more (e.g., second) offsets; the target cell meets the event condition (e.g., event A4 on the target cell, event A3 comparing source and target, etc.) after applying one or more (e.g., second) offsets. The source and target cells satisfy (e.g., a second) condition (e.g., the target cell satisfies event A3 / A4 / A5, and N cells in the target set satisfy the threshold) and a certain number of cells in the candidate set satisfy (e.g., a second) condition (e.g., the target cell satisfies event A3 / A4 / A5, and N cells in the source set are below the second threshold, or fewer than N cells are determined to be in the LTM active set); and / or a certain number of target cells satisfy event conditions (e.g., N target cells satisfy event A3 / A4 / A5). The number of target cells and / or cells in the LTM active set may depend on the elapsed time, such as the time elapsed since the last LTM cell handover (e.g., a first number if the elapsed time is below the threshold, otherwise a second number).

[0220] In some representative embodiments, WTRU 102 may receive information indicating at least one configuration associated with (e.g., for identifying) an active LTM set and / or a target LTM set. For example, the configuration for the LTM set may include information indicating any of the following: a list of cell identities, a list of PCIs, and / or a list of SSBs. The lists may be associated with an active LTM set. The lists may be associated with a target LTM set.

[0221] For example, WTRU 102 may receive information indicating at least one configuration for L1 and / or L3 measurement events. For example, the triggering conditions for the event may be based on criteria (or multiple criteria) (e.g., RSRP threshold) for determining suitable additional candidate cells (e.g., in addition to the target SpCell), the number of n additional candidates to be considered in the criteria, and / or a timer value for determining whether to use the n additional candidates.

[0222] For example, WTRU 102 can determine the number of additional candidates as a first value. WTRU can determine the first number of additional candidates (e.g., 0) based on the elapsed time, such as when the elapsed time since the last LTM cell handover is less than a configured threshold (e.g., a timer value), and otherwise determine it as a second value (e.g., n is greater than 0).

[0223] For example, WTRU 102 can perform measurements on active and target LTM sets. WTRU 102 can determine which cells are to be included in the active and target LTM sets based on any of the following: cells on which WTRU 102 maintains downlink synchronization; cells on which WTRU 102 has effective timing advance (e.g., UL synchronization); cells on which WTRU 102 actively reports L1 CSI beam measurements; cells on which WTRU 102 is configured to perform TRS tracking; and / or cells above a radio quality threshold.

[0224] For example, WTRU 102 may determine (e.g., a first) offset to be applied to any serving cell measurement based on cells in the active and / or target LTM set. WTRU 102 may also determine (e.g., a second) offset to be applied to any neighboring cell measurement based on cells in the target LTM set.

[0225] For example, WTRU 102 can evaluate measurement events based on serving cell measurements (e.g., after applying a first offset) and / or neighbor cell measurements (e.g., after applying a second offset). If the triggering conditions of an event are met, WTRU 102 can perform any of the following: send a measurement report associated with the event (e.g., including information indicating the identifiers of any additional cells considered in the event and / or the primary cell that triggered the event); and / or perform an associated conditional reconfiguration, if configured; and / or send information indicating the execution of the conditional reconfiguration (e.g., including information indicating the identifiers of any additional cells considered in the event and / or the primary cell that triggered the event).

[0226] Figure 8 This is a system diagram illustrating an example of adjacent region 802 and candidate LTM region 804. Figure 8 The diagram illustrates two regions of a cell. One region can be a neighboring region 802, and the other region can be a candidate LTM region 804 containing a set of LTM candidate cells 806. For example, the two regions can be associated with two CUs. The WTRU 102 can be configured with a set of LTM candidate cells 806 in one of the regions (e.g., CUs). Figure 8In this configuration, WTRU 102 is connected to an SpCell / PCell and is additionally configured to perform additional procedures related to two additional target LTM candidate cells 808 (e.g., neighboring cells from adjacent areas). In some examples, WTRU 102 may perform L1 CSI measurements on these two additional target cells and / or maintain downlink and / or uplink synchronization. Since the two additional target candidate cells 808 are now “ready” for WTRU 102 to perform LTM procedures (e.g., WTRU 102 may receive a MAC CE triggering a fast reconfiguration / handover to one of these cells), these cells may be additionally considered to contribute to the overall serving cell quality at L3 when compared to cells outside the configured LTM candidate set 804. WTRU 102 can derive the quality of the active LTM set based on measurements of cells within the active LTM set (e.g., any cell with measurements above a threshold, any cell for which WTRU 102 has a valid TA, any cell for which WTRU 102 maintains DL synchronization, and / or any cell on which WTRU 102 actively reports CSI information). For example, the active LTM candidate set 804 may include a subset of cells that are configured candidate LTM cells 808. Since the overhead and latency associated with LTM handover are improved compared to L3 handover, it may be desirable to perform LTM on L3 mobility where possible. Therefore, by considering the active LTM candidate cells 808 in the L3 cell quality, the perceived cell quality of the active LTM set can be improved compared to considering only the current PCell. With the increased quality derived by considering additional cells, L3 measurement event assessment can compare the quality of the active LTM set with one or more potential target cells. Target cells can be derived using regular cell quality (e.g., comparing the LTM set quality with the quality of neighboring cells). In some examples, the quality of the target cells can be derived using the LTM set quality. The target LTM set can be determined, for example, using a list of cell identities or PCIs, and WTRU 102 can include cells in the target LTM set where the corresponding cell quality and / or beam quality measurements are above a configured threshold. For example, the target LTM set can include a subset of cells from neighboring areas of multiple cells. In this way, WTRU 102 may be able to derive the target LTM set quality based on multiple potential LTM candidate cells that have not yet been considered in this way. WTRU 102 can then perform a comparison between the current (e.g., active) LTM set and the potential (e.g., target) LTM set, and (e.g., only) send a measurement report or perform a CHO when the target set is considered to have higher quality than the current set.L3 reconfiguration can subsequently occur from the current set to the target set. This can involve changes to the gNB / CU and requires L2 reset, security reinitialization, configuration of a new set of LTM candidate cells, and so on. Since L3 reconfiguration implies more overhead and longer latency, if the evaluation quality of the target set is better than that of the current set, L3 reconfiguration can be performed (e.g., only).

[0227] Figure 9 This is a process diagram illustrating an example process for determining and measuring the active LTM set. Figure 9 At 902, WTRU 102 may receive information indicating a configuration for identifying the active LTM set and / or the target LTM set. For example, this configuration may include any of the following: a list of cells and / or beams that must be included in the export; a list of cells and / or beams that may not be included in the export; one or more radio quality thresholds to be used in the export; an indication of one or more standards to be used; a maximum and / or minimum number of cells to be included in the export; an offset and / or scaling to be applied to the quality export; an association of each serving beam to be included in the virtual cell quality export with a list of beams on other cells; an indication of using the exported LTM set quality as the quality of the source or target cell; and / or an indication of using the exported LTM set quality as an offset to be applied to the quality of the source or target cell (e.g., on top of it).

[0228] For example, the WTRU 102 may be configured with one or more specific cells and / or beams (e.g., a set of LTM sets) to include LTM set quality exports and / or exclude from LTM set quality exports. As an example, the WTRU 102 may be configured with any of the following: a list of cell identities to be considered; a list of PCIs to be considered; a list of SSBs and / or CSI RSs to be considered; and / or a list of LTM candidate cell identities to be considered.

[0229] For example, the WTRU 102 can be configured with one or more radio quality thresholds to be used, such as minimum quality thresholds for beams and / or cells to be included in the output. The thresholds can be absolute or relative to the serving cell, and / or absolute or relative to the best cell. As an example, the WTRU 102 can be configured with absolute thresholds (e.g., absThreshSS-BlocksConsolidation As another example, the threshold can be a relative threshold, such as a threshold that allows the inclusion of a beam and / or cell within X dB of the serving cell (PCell) and / or within X dB of the best cell and / or best beam.

[0230] For example, WTRU 102 can be configured with indications of the standards to be used, such as using a cell with measurements above the radio quality threshold, using the cell in the assessment if WTRU 102 is maintaining DL and / or UL (e.g., with a valid TA), and / or using the cell in the assessment if a CSI report for that cell is currently being actively sent.

[0231] For example, WTRU 102 can be configured with a maximum and / or minimum number of cells to be included in the export. As an example, WTRU 102 can be configured with a maximum number of cells within the LTM set to be considered in the LTM set quality export. For example, WTRU 102 can be configured to include beams from no more than N cells in the cell quality export. WTRU 102 can select N cells with the beam having the highest L1 measurement (e.g., RSRP). As another example, WTRU 102 can be configured with a minimum number of cells such that if beams from fewer than N cells meet a minimum quality threshold (e.g., ...), ... absThreshSS-BlocksConsolidation If a standard or multiple standards are used, then WTRU 102 should use normal (or conventional) cell quality export.

[0232] For example, the WTRU 102 can be configured with one or more offsets and / or scaling factors to be applied to quality export. For instance, LTM ensemble quality can be exported by including an offset of the optimal beam measurement. For example, the optimal beam may have an RSRP of X dBm, and an offset can be added to the beam measurement for each additional beam that satisfies one or more criteria (e.g., a minimum threshold). As another example, the optimal beam measurement can use a scaling factor based on the number of other beams that satisfy one or more criteria.

[0233] For example, the WTRU 102 can be configured with an association of each serving beam with a list of beams on other cells to be included in the virtual cell quality export. As an example, the WTRU 102 can be provided with a list of cells and / or beams for each Pcell and / or the best beam for use in the export. For instance, for any given current Pcell, for any given serving beam, and / or for any best beam, a list of other beams can be provided to the WTRU 102 for measurement and inclusion in the LTM set export.

[0234] For example, WTRU 102 can be configured to indicate whether the derived LTM ensemble quality is used as the quality of the source or target cell or as an offset to be applied to the quality of the source / target cell (e.g., on top of it). As an example, an indication regarding the method of LTM ensemble quality derivation can be provided. The indication can configure WTRU 102 to perform LTM ensemble quality derivation based on beam averaging from multiple cells, as described above, or based on adding an offset to the cell quality derivation to derive the LTM ensemble quality.

[0235] exist Figure 9 At position 904, WTRU 102 can receive information indicating the configuration for L1 or L3 measurement events. The triggering conditions for the event may be based at least in part on one or more criteria (e.g., RSRP threshold) used to determine suitable candidate cells to be added, such as in addition to the target SpCell. For example, the configuration may include any of the following: the number of additional cells to consider (e.g., n), and / or a timer value (e.g., time period or duration) or another value (e.g., 0) used to determine whether to use (e.g., n) additional cells.

[0236] The triggering conditions for a measurement event may be based at least in part on a comparison of at least one LTM set quality (e.g., serving LTM candidate set, target LTM candidate set) with one or more of the following: another LTM set quality; individual cell quality; cell quality threshold; maximum time since the last LTM cell handover; and / or minimum time since the last LTM cell handover.

[0237] For example, the quality of an LTM set can be compared with the quality of another LTM set. As an example, WTRU 102 can compare the serving and / or current LTM set with a potential target set. The current set may include cells and / or beams (e.g., LTM candidate configurations) that WTRU 102 has already configured, and / or the target set may be a list of cells and / or measurement resources with indications of these sets. As an example, WTRU 102 can be configured to evaluate normal (or routine) measurement events (e.g., as specified in 3GPP TS 38.331 §5.5.4). The measurement results of the serving cell (e.g., Ms) and the measurement results of neighboring cells (e.g., Mn) can be the LTM set quality derived from the current and target sets.

[0238] For example, LTM set quality can be compared to individual cell quality (e.g., serving cell outside the LTM set, target cell outside the LTM set). As an example, WTRU 102 can be configured to evaluate normal (or routine) measurement events (e.g., event A3, a neighbor becomes a better offset than SpCell, as specified in 3GPP TS 38.331 §5.5.4). The measurement result of the serving cell (e.g., Ms) can be LTM set quality, and the measurement result of the neighboring cell (e.g., Mn) can be the normal (or routine) cell quality of the neighboring cell.

[0239] For example, the LTM set quality can be compared to one or more cell quality thresholds. As an example, WTRU 102 can compare the current or target LTM set quality to an absolute threshold. As an example, WTRU 102 can be configured with measurement events such as event A1 (service becomes better than a threshold) and event A2 (service becomes worse than a threshold), from which the derived LTM set quality is used as a measurement result for the serving cell (e.g., Ms). As another example, WTRU 102 can be configured with measurement events such as event A4 (neighbor becomes better than a threshold), from which the derived LTM set quality can be used as a measurement result for the neighboring cell (e.g., Mn). As yet another example, WTRU 102 can be configured with measurement events such as event A5 (SpCell becomes worse than threshold 1 and neighbor becomes better than threshold 2), and the current and target derived LTM set quality can be used as derived measurements for the serving cell (e.g., Ms) and the neighboring cell (e.g., Mn). For example, the current LTM set quality can be used as a measurement result for the serving cell. For example, the target LTM set quality can be used as a measurement result for the neighboring cell.

[0240] For example, the maximum time since the last LTM cell handover can be used to compare LTM set quality. As an example, WTRU 102 can be configured to perform an evaluation based on LTM set quality up to the maximum time since the last LTM cell handover (e.g., before the maximum time has elapsed). This can be used, for example, to configure WTRU 102 to use LTM set quality when SpCell changes frequently due to LTM (e.g., because WTRU 102 is mobile), and to use serving cell quality when WTRU 102 becomes stationary.

[0241] For example, the minimum time since the last LTM cell handover can be used to compare LTM set quality. As an example, WTRU 102 can be configured to (e.g., only) perform an evaluation based on LTM set quality after a certain amount of time has elapsed since the last LTM cell handover. This can be used, for example, to configure WTRU 102 to (e.g., only) use LTM set quality after WTRU 102 has had time to begin early synchronization of the target candidate cell after the LTM cell handover.

[0242] exist Figure 9 At position 906, WTRU 102 can determine the number of additional candidates to be used in the LTM set quality derivation. For example, when the time elapsed since the last LTM cell handover is less than a threshold (e.g., in...). Figure 9 When the timer value configured at position 904 is used, WTRU 102 can determine the number of additional candidates as a first value (e.g., 0), and otherwise determine it as a second value (e.g., in...). Figure 9 (The n configured at position 904 in the original text). As another example, WTRU 102 can use the time elapsed since the last LTM candidate set handover (e.g., where PCell changed from a cell in LTM set x to a cell in LTM set y). As another example, WTRU 102 can determine the number of additional candidates from a set of values. In some representative embodiments, WTRU 102 can use multiple elapsed time values, serving cell quality, and / or one or more other criteria to select the number of additional candidates.

[0243] exist Figure 9 At position 908, WTRU 102 can perform measurements on active and / or target LTM sets (e.g., based on...). Figure 9 The configuration received at positions 902 and 904 and based on Figure 9 (The determination at 906 in the text). For example, WTRU 102 may determine the cells to be included in the active and / or target LTM set based on any of the following: cells on which WTRU 102 maintains downlink synchronization; cells on which WTRU 102 has effective timing advance (e.g., UL synchronization); cells on which WTRU 102 actively reports L1 CSI beam measurements; cells on which WTRU 102 is configured to perform TRS tracking; cells on which measurements are above a radio quality threshold; and / or the best N cells (cells with the highest radio quality up to the maximum number of cells).

[0244] In some representative embodiments, WTRU 102 may derive LTM set quality only for the active LTM set, and WTRU 102 may derive normal (or conventional) cell quality for neighboring cells. In some representative embodiments, LTM set quality may be determined (e.g., separately) for both the active and target LTM sets.

[0245] exist Figure 9 At position 910, WTRU 102 can determine a first offset to be applied to the serving cell measurement based on cells in the active LTM set. WTRU 102 can determine a second offset to be applied to the neighboring cell measurement based on cells in the target LTM set (e.g., if evaluated).

[0246] In some representative embodiments, the desired result can be achieved in a certain number of cells (e.g., n). Figure 9 After one or more criteria at point 908 (e.g., only if a certain number of cells (e.g., n) meet the criteria), Figure 9 When applying one or more criteria at 908, a first offset and / or a second offset are used. In some representative embodiments, the offset to be applied to the LTM ensemble may be selected based on (e.g., depending on) the number of cells that meet one or more criteria. For example, an offset of X dB may be added for one cell, an offset of 2*X dB may be added for two cells, and so on. In some representative embodiments, an average cell quality value may be used. For example, the linear average of all cells that meet one or more criteria up to a maximum number N may be used as the LTM ensemble quality. For example, the offset to be applied may be selected based on (e.g., depending on) the number of additional cells determined at 906.

[0247] exist Figure 9At point 912, WTRU 102 can evaluate measurement events based on serving cell measurements (e.g., after applying a first offset) and neighboring cell measurements (e.g., after applying a second offset). For example, WTRU 102 can use the derived LTM set quality as the source / target cell quality based on this configuration, or apply the derived LTM set quality to the serving / target cell quality (e.g., on top of it). For example, for any measurement event described in 3GPP TS 38.331 §5.5.4, WTRU 102 can use the current LTM set quality instead of the serving cell quality (e.g., Ms). For example, for any measurement event described in 3GPP TS 38.331 §5.5.4, WTRU 102 can use the target LTM set quality instead of the neighboring cell quality (e.g., Mn). For example, WTRU 102 can use any type of comparison or evaluation to compare the derived current and / or target LTM set quality with another LTM set quality and / or cell quality.

[0248] exist Figure 9 At point 914, when the triggering conditions of the assessed event are met (e.g., the minimum time period has elapsed since the last LTM cell handover and the maximum time period has not elapsed since the last LTM cell handover), WTRU 102 may perform any of the following: send a measurement report associated with the event; and / or perform an associated conditional reconfiguration (e.g., if configured).

[0249] In some representative embodiments, where the WTRU 102 is already configured with RRC measurement events, objects, and / or reports, the WTRU 102 can send a measurement report associated with the event. For example, the measurement report may include information indicating any of the following: the quality of the derived LTM set; details of the specific cell and / or beam used for the derived measurement (e.g., beam ID or cell ID); normal (or regular) cell and / or beam measurement results for the LTM set and / or neighboring cells; and / or the quality of the derived LTM set.

[0250] In some representative embodiments, WTRU 102 may perform an associated conditional reconfiguration (e.g., if configured). For example, WTRU 102 may send information indicating the execution of the conditional reconfiguration (e.g., in a reconfiguration completion message or in a subsequent message). The information sent may include any of the following: the quality of the derived LTM set; details of the specific cell and / or beam used for the derived LTM set (e.g., beam ID or cell ID); normal (or regular) cell and / or beam measurements of the LTM set and / or neighboring cells; and / or the quality of the derived LTM set.

[0251] Longer-term measurement and evaluation across multiple LTM serving cells In some representative embodiments, the network may want to configure relatively long TTT values ​​for L3 measurement events to prevent premature handover out of the LTM set. A side effect could be that the WTRU 102 uses LTM to handover frequently between cells (e.g., more frequently than per TTT), and L3 measurement events might trigger too late (or never) because the serving cell changes within the TTT. To address this, the triggering conditions can be enhanced to allow any (e.g., all) serving cells within the TTT to be considered, such as when a candidate cell is significantly better than the current serving cell.

[0252] For example, when WTRU 102 uses LTM to handover from a first serving cell to a second serving cell, WTRU 102 can derive L3 cell quality and evaluate L3 event triggering based on measurements applicable to both the first and second serving cells (e.g., as if the serving cell were a single serving cell). WTRU 102 can continue (e.g., currently) the evaluation of serving cell quality and measurement event triggering after the cell change. After the cell change, WTRU 102 can (e.g., continue) use previous (one or more) serving cell measurements as if they were current cell measurements. WTRU 102 can trigger a measurement report where at least one condition is met for the current serving cell over the TTT duration (e.g., evaluation using the first and second serving cells). WTRU 102 can perform the aforementioned operations if the measurement results for a candidate cell are above a threshold; otherwise, WTRU 102 can trigger (e.g., only) if the condition is met over the TTT for the current serving cell. For example, the L3 filtering result for the second serving cell can be based on the L3 filtering result for the first serving cell during cell handover.

[0253] In some representative embodiments, the WTRU may receive information indicating a configuration associated with determining (e.g., how to derive) the serving cell quality using L3 filtering by acquiring L1 RSRP, RSRQ, and / or SINR samples from any cell that is already a Pcell within the filtering window. For example, the configuration may include information indicating at least one of filter coefficients, RS type, and / or RS index.

[0254] For example, WTRU 102 can receive information indicating the configuration for L1 and / or L3 measurement events. The configuration may include information indicating that the evaluation on TTT (e.g., time period, duration, interval) is performed using thresholds of measurement results from any cell that is already a serving cell and / or neighboring cell measurement results while the TTT is running (e.g., during the TTT).

[0255] For example, WTRU 102 can determine the conditions for an event to be met for the first serving cell and neighboring cells within a first time period. The first time period can be less than (e.g., shorter than) TTT.

[0256] For example, WTRU 102 can receive information indicating a handover from the first serving cell to the second serving cell using LTM at the end of the first time period (or no later than the first time period).

[0257] For example, WTRU 102 can determine the conditions for events to be met for the second serving cell and neighboring cells during a second time period. The sum of the first and second time periods can be equal to or greater than TTT. If the result of the neighboring cell is higher than the result of the second serving cell plus a threshold, WTRU 102 can trigger the transmission of a measurement report including information indicating the first and / or second serving cells and / or the first and / or second time periods.

[0258] Figure 10 This is a system diagram illustrating an example of L3 filtering and measurement evaluation. Figure 10 In this context, assume that WTRU 102 is performing LTM using cell 1 1002 and cell 2 1004 while evaluating L3 measurement events that compare the serving cell (e.g., cell 1 then cell 2) with neighboring cells (e.g., cell 3 1006).

[0259] For example, a regular cell quality export can use L1 RSRP measurements provided from each beam of L1, perform beam combining (e.g., select the best N beams for the cell), and apply filters to average the measurement samples over time. However, when LTM is used for handover of serving cells, this type of reconfiguration can occur relatively frequently, making it possible that the serving cell quality export may not be completed at certain times due to insufficient time.

[0260] In some representative embodiments, when LTM is configured, L3 filtering of serving cell quality may not be limited to a single serving cell. For example, the filtering window may include RSRP results from any previous serving cells within the filtering window. Figure 10 In this process, the serving cell changes from cell 1 1002 to cell 2 1004, and cell quality derivation continues during and after the handover from cell 1 1002 to cell 2 1004. WTRU 102 can use samples from both cell 1 1002 and cell 2 1004 as input to a filter to derive the serving cell quality.

[0261] According to 3GPP TS 38.331, (e.g., baseline) measurement filters can (e.g., should) be implemented by WTRU 102 as follows: 1> For each cell measurement, each beam measurement, and each sidelink measurement required according to Clause 5.8.10, for each CLI measurement performed by the UE according to 5.5.3.1, and for each candidate L2 U2N relay UE measurement according to 5.5.3.4: 2. Before using the evaluation report standards or for measurement reports, filter the measured results using the following formula: F n =(1- a )* F n-1 + a * M n in M n It is the latest measurement result received from the physical layer; F n It is an updated filtered measurement result, used to evaluate reporting standards or for measurement reporting; F n-1 These are the old filtered measurement results, where, upon receiving the first measurement result from the physical layer, F 0 is set to M 1; and for MeasObjectNR , a =1 / 2 （ki / 4） ,in k i yes quantityConfigNR The i-th item in the list QuantityConfigNR The corresponding measurement quantity filterCoefficient And i is by MeasObjectNR In quantityConfigIndex Instructions; for other measurements, a =1 / 2 （k / 4） ,in k It is by quantityConfig Received corresponding measurement quantity filterCoefficient For UTRA-FDD, a =1 / 2 （k / 4） , where k is determined by QuantityConfig In quantityConfigUTRA-FDD The received filterCoefficient corresponding to the measured quantity; 2> Adapt the filter to preserve its time characteristics under different input rates, and observe... filterCoefficientk assumes the sampling rate is equal to X ms; assumes non-DRX operation and depends on the frequency range, the value of X is equal to an L1 measurement period within a frequency range as defined in TS 38.133

[14] .

[0262] Note 1: If k If set to 0, no layer 3 filtering is applicable.

[0263] Note 2: The filtering is performed in the same domain as the evaluation report standard or the measurement report, i.e., logarithmic filtering for logarithmic measurements.

[0264] Note 3: The filter input rate is implementation-dependent to meet the performance requirements set in TS 38.133

[14] . For further details on physical layer measurements, see TS38.133.

[0265] Note 4: For CLI-RSSI measurements, whether the filtering is reset during BWP handover depends on the UE implementation.

[0266] In some representative embodiments, previous filtered measurement results (e.g., Fn-1) can be retained after LTM cell handover, such that updated filtered measurement results (e.g., Fn) are based on previous serving cell results (e.g., Fn-1) and current serving cell measurement results (e.g., Mn).

[0267] For measurement event evaluation, the duration of the continuous TTT may need to meet the conditions. In the case of frequent cell changes due to LTM, any measurement event that uses serving cell measurement results as part of the triggering conditions may not trigger because the serving cell measurement has not been evaluated for a sufficiently long time.

[0268] In some representative embodiments, L3 measurement events (e.g., using serving cell measurements configured when LTM was also configured) may (e.g., should) use previous cell measurement results and current cell measurement results as triggering conditions, and TTT can continue to operate after cell handover. An event may (e.g., should) be triggered if the duration of the (e.g., previous or current) serving cell measurement continuing the TTT meets one or more criteria.

[0269] Figure 11 This is a process diagram illustrating an example procedure for L3 filtering and measurement event evaluation. In some representative embodiments, WTRU 102 can... Figure 11At position 1102, information indicating configuration is received regarding how to obtain L1 samples (e.g., RSRP, RSRQ, and / or SINR) from any cell that is already a Pcell (e.g., the UE's) within the filtering window to derive the serving cell quality using L3 filtering. For example, the configuration may include information indicating any of the following: filter coefficients; RS type; and / or RS index.

[0270] In some representative embodiments, WTRU 102 may receive information indicating a configuration that restricts the cell quality derivation method to certain cells and / or groups of cells. For example, the use of the cell quality derivation method may be associated with a specific measurement event and / or measurement object. As an example, the configuration at 1102 may be received as part of a measurement event and / or conditionally triggered configuration to be applied to the measurement evaluation. As another example, WTRU 102 may receive a (e.g., a single) configuration applicable to any (e.g., all) configuration.

[0271] exist Figure 11 At position 1104, WTRU 102 can receive information indicating the configuration for L1 or L3 measurement events. This configuration may include information indicating that evaluation on TTT can (e.g., will) be performed using measurement results from any cell that is already a serving cell during the TTT. In some representative embodiments, the configuration for cross-cell measurement event evaluation can be independent of the configuration for cross-cell L3 filtering. For example, these features can be configured independently or together.

[0272] For example, WTRU 102 can be configured to perform measurement event assessments, continue TTT (e.g., if performed using LTM) after a cell handover, and consider serving cell quality measurements from both the previous and current cells for one event criterion / multiple event criters. In some representative embodiments, WTRU 102 can receive information instructing the configuration to indicate which cells to include when performing assessments across cells using TTT. For example, WTRU 102 can continue assessments across cells 1 and 2 instead of cells 2 and 3. In some representative embodiments, a list of cells to which a single measurement event applies can be provided to a configuration for that event. For example, a measurement event can be configured to apply when it is in a set of cells (e.g., cells 1, 2, 3), and if any LTM cell handover is performed between the set of cells, any current event criterion assessment can continue and be applied by WTRU 102 as if the set of cells were a single serving cell.

[0273] For example, a measurement event may at least consider the quality of the serving cell. For example, a measurement event may (e.g., also) consider the quality of neighboring cells. In some representative embodiments, it may be based on... Figure 11 The configuration at 1102 uses filtering across multiple cells to derive the measurement results for the serving cell (e.g., Ms).

[0274] In some representative embodiments, WTRU 102 can be configured to evaluate routine measurement events that compare the serving cell with neighboring cells (e.g., event A3, when a neighbor becomes better offset than SpCell, as specified in 3GPP TS 38.331 §5.5.4). Measurements of the serving cell (e.g., Ms) can be derived from previous cell measurements included in the filtering calculation. In some representative embodiments, neighbor cell measurements and evaluations can (e.g., also) continue when the serving cell changes due to LTM.

[0275] In some representative embodiments, WTRU 102 may be configured with measurement events, such as event A1 (service becomes better than the threshold) and / or event A2 (service becomes worse than the threshold) that compare the serving cell to a threshold. For example, the measurement results of the serving cell (e.g., Ms) can be derived from including previous cell measurements in the filtering calculation.

[0276] In some representative embodiments, WTRU 102 may be configured with measurement events, such as event A5 (SpCell becomes worse than threshold 1 and the neighbor becomes better than threshold 2) that compares the serving cell and neighbor cells to thresholds. For example, the serving cell measurement (e.g., Ms) can be derived from including previous cell measurements in the filtering calculation. For example, neighbor cell measurements and evaluations can (e.g., also) continue when the serving cell changes due to LTM.

[0277] exist Figure 11 At position 1106, WTRU 102 can determine that conditions for an event are met, such as during a first time period for the first serving cell and neighboring cells (e.g., the first time period is less than the TTT). WTRU 102 can initiate a TTT period. In some representative embodiments, the measured event may evaluate both the serving cell and one or more neighboring cells (e.g., event A3, a neighboring cell becomes better offset than SpCell). In some representative embodiments, the measured event may evaluate only the serving cell (e.g., event A1, the serving cell becomes better than a threshold). For example, the condition may continue to be met for a first time period shorter than the TTT configured for the event.

[0278] exist Figure 11At point 1108, at the end of the first time period, WTRU 102 may receive information indicating LTM triggering (e.g., MAC CE indicating a new SpCell). WTRU 102 may perform reconfiguration to the indicated SpCell. LTM triggering may (e.g., should) occur before TTT has elapsed.

[0279] exist Figure 11 At point 1110, since WTRU 102 is configured to continue evaluating measurement events after a cell change from the first cell to the second cell, WTRU 102 can determine the conditions for the event being met for the second serving cell and neighboring cells during the second time period (e.g., the same conditions as in 1106). For example, the sum of the first and second time periods is equal to or exceeds the TTT. That is, when the TTT has been running (e.g., during the TTT period), the measurement event conditions are met for the first time period using the first serving cell and for the second time period using the second serving cell, satisfying one or more criteria to trigger the event, because the duration of the TTT, the serving cell, which is not necessarily the same serving cell, has already met the conditions.

[0280] As another example, when an LTM cell handover command is received while the TTT is running, the WTRU 102 can reset the TTT timer, or reset and start a TTT with a different value (e.g., an offset higher than the previous value). The WTRU 102 can continue the event evaluation using measurements from the new serving cell while the timer is running (e.g., during the TTT reset period).

[0281] exist Figure 11 At point 1112, WTRU 102 can trigger the transmission of a measurement report, including information indicating (e.g., identifying) the first and second serving cells and / or time periods, based on a condition that the result of a neighboring cell is higher than the result of the second serving cell plus a threshold. For example, WTRU 102 can indicate all serving cells that have triggered the event. For example, WTRU 102 can indicate the time during which each serving cell has met the condition. For example, WTRU 102 can include filtered measurement results calculated based on more than one serving cell. For example, WTRU 102 can include regular measurement results for each of the cells that met the condition.

[0282] The timer that disables LTM measurement reporting after the L3 switching process. In some representative embodiments, a timer for L1 reporting can be disabled (e.g., temporarily) to limit reporting after an L3 cell handover.

[0283] The examples described herein prohibit race conditions that can resolve situations where an L3 handover is completed but an LTM handover occurs before L3 signaling (e.g., an RRC reconfiguration completion transmission using RLCAM) is completed. This can occur for L3 handovers that include the set of LTMs in the target configuration, or it can occur during the initial LTM setup (e.g., an LTM cell handover occurs before the delivery of an RRC reconfiguration completion corresponding to the LTM setup is completed).

[0284] To provide RRC reconfiguration completion signaling that will be successfully delivered (e.g., to the CU) after an L3 handover, WTRU 102 can be prevented from sending L1 measurement reports and / or performing LTM. Sending L1 measurement reports and / or performing LTM may result in DU-triggered LTM handover and loss of L3 signaling, causing the CU to detect a handover failure or reconfiguration failure. For example, temporary restrictions on L1 reporting to neighbors and / or candidate cells (e.g., current cell beam reporting is still enabled to allow scheduling) can be implemented using timers or by waiting for RLC acknowledgments of RRC messages (e.g., completion) to be transmitted.

[0285] In some representative embodiments, WTRU 102 may receive an RRC reconfiguration message that includes information indicating an LTM measurement pause and / or associated timer values.

[0286] For example, WTRU 102 can perform RRC reconfiguration and can stop LTM L1 measurement reporting for neighboring cells (e.g., if it is already running). WTRU 102 can send an RRC reconfiguration complete message.

[0287] For example, if the elapsed time since receiving the RRC reconfiguration is less than the indicated time (e.g., a timer value) and WTRU 102 receives an LTM cell handover command, WTRU 102 may transmit (e.g., via MACCE) an indication not to perform a cell handover. If an LTM cell handover is received before the timer expires (e.g., the elapsed time is less than the indicated time), WTRU 102 may not perform the LTM cell handover command and may respond with a failure indication.

[0288] For example, if the elapsed time since the transmission or successful acknowledgment of the RRC reconfiguration completion message is less than the indicated time (e.g., a timer value) and WTRU 102 receives an LTM cell handover command, WTRU 102 may transmit (e.g., via MAC CE) an indication not to perform a cell handover. If an LTM cell handover is received before the timer expires (e.g., the elapsed time is less than the indicated time), WTRU 102 may not perform the LTM cell handover command and may respond with a failure indication.

[0289] For example, if a configured RRC measurement event TTT is in progress (e.g., started due to met conditions but not yet expired) and WTRU 102 receives an LTM cell handover command, WTRU 102 can transmit (e.g., via MAC CE) information indicating that cell handover should not be performed. If an LTM cell handover command is received while a configured RRC measurement event TTT is in progress, WTRU 102 may not execute the LTM cell handover command and may respond with a failure indication. For example, TTT in progress could refer to a situation where the time period corresponding to the TTT value has not yet expired. For example, TTT expiration could refer to a situation where the time period corresponding to the TTT value has already expired.

[0290] For example, when a period of time corresponding to the indicated timer value has elapsed since the RRC reconfiguration message was received, the WTRU 102 can start (or resume) the LTM L1 measurement report for the candidate cell.

[0291] For example, when a period of time corresponding to the indicated timer value has elapsed since the transmission or successful acknowledgment of the RRC reconfiguration completion message, the WTRU 102 can start (or resume) the LTM L1 measurement report for the candidate cell.

[0292] For example, under the condition that the configured RRC measurement event TTT is running (e.g., it has started because the conditions are met, but has not yet expired), the UE can stop or suspend LTM L1 measurement reporting for the candidate cell, and when the TTT expires (e.g., and the measurement event is triggered) or stops (e.g., the measurement event criteria are no longer met, and therefore the event is not triggered), WTRU 102 can start (or resume) LTM L1 measurement reporting for the candidate cell.

[0293] Figure 12 This is a process diagram illustrating an example procedure for LTM measurement and execution pause after L3 reconfiguration (e.g., switching). Figure 12At position 1202, WTRU 102 can receive an RRC reconfiguration message that includes information indicating a pause in LTM measurements and execution. For example, a timer value may be indicated in the RRC reconfiguration. For example, the timer value may be derived (e.g., based on the number of LTM candidate cells, and / or whether the RRC reconfiguration is performing certain procedures, such as security reinitialization or L2 reset). For example, a fixed timer may be predetermined and / or provided as a normalized value (e.g., in 5G NR). In some representative embodiments, this indication pauses only LTM measurements and / or measurement reporting. In some representative embodiments, only LTM execution is paused. In some representative embodiments, both measurement and measurement reporting and execution are paused.

[0294] In some representative embodiments, RRC reconfiguration may include information indicating the configuration of one or more LTM candidate cells. For example, the LTM candidate cells may have been previously configured (e.g., reconfigured via an earlier RRC) and may become effective after a new RRC reconfiguration is applied. As an example, RRC reconfiguration may instruct the reconfiguration to be performed using a stored LTM configuration (e.g., applying an LTM reconfiguration indicated by an RRC). In some representative embodiments, RRC reconfiguration may update a previously configured LTM candidate configuration. In some representative embodiments, RRC reconfiguration may instruct the serving cell configuration and may instruct changes to a new SpCell, a new SCell, MCG, and / or SCG, or any combination thereof.

[0295] In some representative embodiments, RRC reconfiguration can indicate a handover from one set of LTM cells to another, such as if WTRU 102 needs to be reconfigured from one CU to another.

[0296] exist Figure 12 At position 1204, WTRU 102 may apply the received RRC reconfiguration and stop any LTM-based measurement reports (e.g., if operational). LTM-based measurement reports may refer to reports from any LTM candidate cell using L1 measurement events, L1 CSI reports, and / or L3 reports. For example, WTRU 102 may start a timer equal to the indicated value in the RRC reconfiguration (e.g., determining the duration). For example, WTRU 102 may start a timer equal to a derived or implicit value (e.g., determining the duration). In some representative embodiments, the timer may be started upon receiving an RRC reconfiguration message. In some representative embodiments, the timer may be started upon transmitting an RRC reconfiguration completion message. In some representative embodiments, the timer may be started upon receiving an RLC acknowledgment corresponding to the successful delivery of the RRC reconfiguration completion message.

[0297] In some representative embodiments, the first type of L1 CSI reporting may be suspended, while the second type of L1 CSI reporting may not be suspended. For example, periodic L1 CSI reporting may be suspended, while non-periodic L1 CSI reporting may not be suspended.

[0298] exist Figure 12 At position 1206, WTRU 102 can encode and transmit an RRC reconfiguration completion message. When LTM operation is suspended, WTRU 102 can perform transmissions, including any necessary MAC, RLC, and / or PDCP retransmissions, without cell change due to LTM. Therefore, messages can be delivered on the cell intended for reconfiguration according to RRC, thus avoiding any potential error conditions that might arise from separately controlled mobility procedures (e.g., LTM controlled by the DU and RRC controlled by the CU).

[0299] exist Figure 12 At points 1208 and 1210, if a MAC CE (e.g., a MAC CE with an indication to perform LTM cell handover) is received, and the timer is still running (e.g., the elapsed time since receiving the RRC reconfiguration is less than the indicated timer value, or the elapsed time since transmitting or successfully acknowledging the completion of the RRC reconfiguration is less than the indicated timer value), then WTRU 102 may not apply the indicated MAC CE. For example, WTRU 102 may not perform LTM reconfiguration for the indicated candidate configuration ID. In some representative embodiments, WTRU 102 may transmit a failure indication, such as a failure message using a MAC CE or using an RRC reconfiguration. In some representative embodiments, WTRU 102 may include information indicating a cause or reason for the failure, which indicates that the failure is due to the LTM pause timer running. If the timer stops running (e.g., the time elapsed since the RRC reconfiguration was received is greater than or equal to the indicated timer value, or the time elapsed since the RRC reconfiguration was transmitted or successfully acknowledged is greater than or equal to the indicated timer value), the WTRU 102 may perform LTM (e.g., perform cell handover to the indicated candidate configuration, or begin measurement, synchronization, or any process applicable to LTM) according to the received instructions.

[0300] In some representative embodiments, priority quantities (e.g., high priority and / or low priority) can be defined. For example, priorities can be indicated by indices (e.g., 1 means high priority and 0 means low priority). The priority index can define whether L1 / 2 (LTM) cell handover or L3 handover has a higher priority. Priorities can be configured and / or indicated. For example, priorities can be indicated in the MAC CE. In some representative embodiments, if a MAC CE indicating cell handover is received and the priority indicates that L1 / 2 cell handover has a higher priority, WTRU 102 can perform an L1 / 2 handover. In some representative embodiments, if a MAC CE indicating cell handover is received and the priority indicates that L3 cell handover has a higher priority, WTRU 102 can abort the L1 / 2 handover when the L3 handover is pending (e.g., an RRC reconfiguration message has been received).

[0301] exist Figure 12 At positions 1212 and 1214, when the timer expires (e.g., the time elapsed since receiving the RRC reconfiguration is greater than or equal to the indicated timer value), the WTRU 102 can resume the L1 measurement or other measurements related to the LTM, and can execute any commands received from the DU (e.g., MAC CE) and the like.

[0302] PCell identifier when generating RRC messages using LTM In some representative embodiments, the identifier of the PCell in use is used when generating an RRC message while using LTM. For the UL case, a race condition can be resolved where an L3 measurement report is triggered, but an LTM handover occurs before the RRC message is transmitted. This could cause the L3 measurement report to be transmitted to the wrong cell (e.g., not the cell on which the event is configured). If the same measurement configuration (e.g., ID) is configured on the target cell, there may be ambiguity regarding on which cell the event was triggered. For the DL case, a race condition can be resolved where an RRC reconfiguration message is transmitted by the CU, but the DU performs LTM. If the RRC message does not contain a configuration specific to the old cell group served by the first DU (e.g., DU#1), the CU can safely retransmit the RRC message to WTRU 102 via the second DU (e.g., DU#2). Problems may occur if the content of the RRC message has an outdated configuration associated with the old serving cell group on the first DU. If RRC messages are retransmitted to WTRU 102 via the second DU, WTRU 102 may fail to apply outdated RRC configurations because it references the old serving cell group and WTRU 102 is connected to the new serving cell group. This could trigger a connection re-establishment for WTRU 102. If RRC messages are not retransmitted to WTRU 102 via the second DU, any new RRC messages from the same SRB will have to use a new PDCP sequence number (SN), as mandated for replay protection using the same AS security context. This could create a PDCPSN gap. Since the default value of the t-reordering timer for SRB1 is infinity, the t-reordering timer may never expire, and the SRB's PDCP SDU may become undeliverable to the upper layer.

[0303] In some representative embodiments, information indicating the cell identifier (e.g., PCell ID) may be included in the UL RRC message corresponding to the PCell when a corresponding event (e.g., a measurement event, RRC reconfiguration) is triggered. For example, an RRC reconfiguration may be triggered, and the RRC reconfiguration completion message may include information indicating whether an RRC reconfiguration and / or L2-triggered reconfiguration has occurred.

[0304] In a representative embodiment, WTRU 102 may receive information indicating L3 measurement events and / or reporting configurations. WTRU 102 may receive information indicating LTM configurations. WTRU 102 may receive information indicating configurations for including current PCell information in the L3 measurement report (e.g., any candidate cell whose measurement results are higher than the serving cell in the latest L1 and / or L2 reports, with or without an added offset). WTRU 102 may perform measurement evaluation on the current cell and transmit L1 and / or L2 measurement reports. WTRU 102 may determine the trigger for transmitting L3 measurement reports based on the L3 measurement configuration. If the L1 and / or L2 measurement reports indicate that the candidate cell's measurement results are higher than the serving cell's (e.g., with an offset), WTRU 102 may transmit an L3 measurement report including information indicating the current PCell. WTRU 102 may receive LTM cell handover commands and complete RRC transmission on the new cell.

[0305] In a representative embodiment, WTRU 102 may receive an RRC reconfiguration message in the source cell. WTRU 102 may apply the RRC reconfiguration and transmit an RRC reconfiguration complete message (e.g., before LTM). The RRC reconfiguration complete message may include information indicating that the RRC reconfiguration was completed due to the application (e.g., only) of the RRC reconfiguration and information indicating the source cell (e.g., PCI).

[0306] In a representative embodiment, WTRU 102 may receive an RRC reconfiguration message in the source cell. WTRU 102 may apply the RRC reconfiguration. WTRU 102 may receive (or determine) an LTM trigger and reconfigure to the new cell. WTRU 102 may transmit an RRC reconfiguration complete message, which includes information indicating that the RRC reconfiguration was completed due to the application of RRC reconfiguration and LTM reconfiguration, and information indicating the source cell (e.g., PCI).

[0307] For example, LTM-only reconfiguration can cause WTRU 102 to transmit an RRC reconfiguration complete message that does not include any indication (e.g., the source cell's PCI). As another example, the RRC reconfiguration complete message may include information indicating that the message was due to LTM-only reconfiguration being applied.

[0308] For any transmitted RRC message, WTRU 102 may include a cell ID to indicate which cell WTRU 102 was in when the RRC message transmission was triggered. The cell ID can be a PCI, serving cell ID, candidate cell ID, or any value that can identify the cell. This identifier resolves the problems introduced by RRC reconfiguration triggered by L1 / 2, since the cell may change after being triggered by the DU, and the CU may not be aware of this. The cell identifier in the uplink RRC message received by the CU resolves any ambiguity.

[0309] In some examples, the cell identifier may correspond to the cell that triggered the measurement event (e.g., RRC measurement report).

[0310] In some examples, the cell identifier may correspond to the cell on which a mobility command (e.g., an RRC reconfiguration or MAC CE instructing LTM to perform) is received.

[0311] Figure 13 This is a process diagram illustrating an example procedure that indicates the current PCell identity in a triggered measurement report. Figure 13 At 1302, WTRU 102 can determine that a measurement event has been triggered. WTRU 102 can generate an RRC measurement report. The generated RRC measurement report may include information indicating the cell identifier of the current PCell. For example, the RRC measurement report may include fields indicating the current PCell ID and / or the PCell on which the measurement event was triggered. At 1304, WTRU 102 can perform LTM. To transmit the RRC measurement report (e.g., submit it to a lower layer for transmission), it can... Figure 13 1304 or 1306 in the cell physically transmits RRC measurement reports on any cell (e.g., if a MAC CE is received before the transmission has been successfully completed).

[0312] In some representative embodiments, additional indications may be provided in the RRC reconfiguration complete message. For example, a MAC CE triggering LTM may be received after receiving the RRC reconfiguration. The MAC CE triggering LTM may be received before transmitting the RRC reconfiguration complete message (e.g., while WTRU 102 is still processing and applying the RRC reconfiguration).

[0313] The MAC CE can be received after the RRC reconfiguration complete message has been submitted to a lower layer for transmission (e.g., WTRU 102 may have the RRC reconfiguration complete message in the RLC or HARQ buffer for transmission / retransmission). Because for some LTM cell changes (e.g., within a DU), the MAC and RLC are not reset, the RRC reconfiguration complete message can be transmitted to a different cell than the one indicated in the RRC reconfiguration. If the RRC message does not contain configuration information specific to the old cell group served by DU1, the CU can securely retransmit the RRC message to WTRU 102 via DU2.

[0314] There is a potential issue where RRC messages contain outdated configuration information associated with an older serving cell group on DU1. For example, if an RRC message is retransmitted to WTRU 102 via DU2, WTRU 102 may fail to apply the outdated RRC configuration because it references the older serving cell group and WTRU 102 is connected to a new serving cell group. This can trigger a UE connection re-establishment. Alternatively, if an RRC message is not retransmitted to WTRU 102 via DU2, new RRC messages for the same SRB will have to use a new PDCP sequence number, as mandated for replay protection using the same AS security context. This creates a PDCP SN gap. Since the default value of the t-reordering timer for SRB1 is infinity, the t-reordering timer may never expire, and the SRB's PDCP SDU may no longer be delivered to the upper layer.

[0315] In some representative embodiments, WTRU 102 may include (e.g., in a measurement report) information indicating that the RRC reconfiguration complete message is a response to an RRC reconfiguration (e.g., not a MAC CE indicating an LTM). In some representative embodiments, WTRU 102 may include information indicating that the RRC reconfiguration complete message is transmitted before any LTM trigger is received. In some representative embodiments, in addition to the reconfiguration indicated by the MAC CE, WTRU 102 also indicates that the RRC reconfiguration complete message is a response to an RRC reconfiguration. In some representative embodiments, WTRU 102 may include information indicating a received RRC reconfiguration (e.g., a message ID, counter value, and / or security token corresponding to the received RRC reconfiguration).

[0316] Figure 14 This is a process diagram illustrating an example procedure for RRC reconfiguration. For example, in the case of RRC reconfiguration during LTM execution, an RRC reconfiguration completion flag can be used. Figure 14At 1402, WTRU 102 may receive an RRC reconfiguration message. At 1404, WTRU 102 may apply the reconfiguration and set a value (e.g., a flag in the RRC reconfiguration complete message) to indicate that the RRC reconfiguration has been applied. For example, WTRU 102 may (e.g., additionally) indicate the primary cell in the RRC reconfiguration complete message (e.g., where the PCell ID of the RRC reconfiguration has been received). WTRU 102 may receive a MAC CE indicating LTM cell handover at 1406 (e.g., before the RRC reconfiguration complete message has been submitted to the lower layer for transmission). WTRU 102 may perform LTM at 1408. For example, WTRU 102 may set (e.g., additionally) a value in the RRC reconfiguration complete message to indicate that LTM has been additionally performed. In some representative embodiments, WTRU 102 may include the LTM candidate cell ID (e.g., as the value at 1410) in the RRC reconfiguration complete message. After the RRC transmission measurement report (e.g., submitted to a lower layer for transmission), the RRC reconfiguration complete message can be physically transmitted at 1412 on any cell (e.g., if a MAC CE is received before the transmission has been successfully completed).

[0317] Figure 15 This is a process diagram illustrating an example process according to certain representative embodiments. Figure 15 At 1502, WTRU 102 may (e.g., implement a method to) receive information indicating configuration information associated with the quality of LTM. WTRU 102 may receive information indicating measurement events at 1504. At 1506, WTRU 102 may determine the quality of a first LTM set based on measurements of a first set of beams from a first plurality of cells. At 1508, WTRU 102 may send a measurement report associated with the measurement event and / or perform a conditional reconfiguration based on, for example, (1) the determined quality using the first LTM set satisfies the measurement event and (2) the time elapsed since the last LTM cell handover.

[0318] In some representative embodiments, WTRU 102 may (e.g., implement a method to) receive information indicating configuration information associated with the quality of LTM. WTRU 102 may receive information indicating measurement events. WTRU 102 may determine the quality of a first LTM set based on measurements of a first set of beams from a first plurality of cells. WTRU 102 may send a measurement report associated with the measurement event and / or perform a conditional reconfiguration based on, for example, (1) the determined quality using the first LTM set satisfies the measurement event and (2) the time elapsed since the last LTM cell handover.

[0319] For example, WTRU 102 can determine the quality of a second LTM set based on measurements of a second set of beams from a second plurality of cells. Using the determined quality of the first LTM set and the determined quality of the second LTM set, a measurement event can be (e.g., determined) to be satisfied.

[0320] For example, WTRU 102 may determine a first set of beams as a subset of (e.g., first) multiple beams from a first plurality of cells, and / or determine a second set of beams as a subset of (e.g., second) multiple beams from a second plurality of cells.

[0321] For example, WTRU 102 can determine the quality of a serving cell or target cell outside the first LTM set. Using the determined quality of the first LTM set and the determined quality of the serving or target cell, a measurement event can be (e.g., determined) to be satisfied.

[0322] For example, WTRU 102 can perform the final LTM switch before the measurement event is met.

[0323] For example, a measurement report may include information indicating the determined quality of the first LTM set, and / or conditional reconfiguration may include sending information indicating the determined quality of the first LTM set.

[0324] In some representative embodiments, WTRU 102 may (e.g., implement a method to) receive information indicating configuration information for an active LTM set and a target LTM set. WTRU 102 may receive information indicating measurement events associated with a serving cell (e.g., associated with the active LTM set) and / or neighboring cells (e.g., associated with the target LTM set). WTRU 102 may determine the number of cells based on the time elapsed since the last LTM handover (e.g., performed). WTRU 102 may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. WTRU 102 may send measurement reports associated with measurement events and / or perform conditional reconfiguration based on measurements of the serving cell modified by a first offset and / or measurements of the neighboring cells modified by a second offset. For example, the first offset may be based on measurements of the active LTM set (e.g., determined using measurements of the active LTM set). For example, the second offset may be based on measurements of the target LTM set (e.g., determined using measurements of the target LTM set).

[0325] For example, WTRU 102 can determine the number of additional cells as a first value based on the time elapsed since the last LTM handover being less than a threshold, or determine the number of additional cells as a second value based on the time elapsed since the last LTM handover being greater than a threshold.

[0326] For example, WTRU 102 can select the number of cells in the active LTM set based on one or more (e.g., a first) criteria, and / or select the number of cells in the target LTM set based on one or more (e.g., a second) criteria. For example, the first and second criteria / multiple criteria can be the same (or different).

[0327] For example, a measurement report may include information indicating a determined number or cells and / or (e.g., specific) cells associated with triggering a measurement event, and / or conditional reconfiguration may include sending information indicating a determined number or cells and / or (e.g., specific) cells associated with triggering a measurement event.

[0328] For example, WTRU 102 can determine a first offset based on measurements of the active LTM set satisfying one or more (e.g., a first) criteria, and / or determine a second offset based on measurements of the target LTM set satisfying one or more (e.g., a second) criteria. For example, the first and second criteria / multiple criteria can be the same (or different).

[0329] For example, the final LTM handover (e.g., performed by WTRU 102) could be the final LTM candidate cell handover.

[0330] In some representative embodiments, WTRU 102 may (e.g., implement a method to) receive information indicating configuration information associated with the quality of the serving cell using L3 filtering. WTRU 102 may receive information indicating measurement events associated with the use of a TTT period and an offset (and / or a scaling factor and / or a threshold). WTRU 102 may determine that a measurement event is met during a first time period for a first serving cell and / or a neighboring cell. The first time period may (e.g., is) be less than the TTT period. WTRU 102 may receive information indicating that the first serving cell is switched to a second serving cell using LTM at the end of the first time period. WTRU 102 may determine that a measurement event is met during a second time period for a second serving cell and / or a neighboring cell. The sum of the first time period and the second time period may (e.g., is) be greater than or equal to the TTT period. WTRU 102 may send a measurement report including information indicating the first serving cell, the second serving cell, and / or the first time period and the second time period based on (1) the measurement result of the neighboring cell being greater than (2) the measurement result of the second serving cell plus an offset (or otherwise the measurement result of the second serving cell modified by the offset). As another example, the measurement results of the second serving cell can be modified by a scaling factor. As another example, a measurement report can be sent based on (1) the difference between the measurement results of the neighboring cell and the measurement results of the second serving cell is greater than (2) a threshold. In some embodiments, any combination of offset, scaling factor and / or threshold can be used.

[0331] For example, WTRU 102 can use any of the L1, L2 and / or L3 measurements to determine the measurement events that are met during a first time period for the first serving cell and / or neighboring cells.

[0332] For example, WTRU 102 can determine the measurement event that is met during a second time period for a first serving cell using L3 filtering and / or a neighboring cell using L3 filtering.

[0333] For example, WTRU 102 can receive information in the MAC CE indicating to switch the first serving cell to the second serving cell.

[0334] For example, the configuration information that WTRU 102 may associate with the quality of the serving cell using L3 filtering may include information indicating one or more filter coefficients for L3 filtering and / or one or more reference signals for L3 filtering.

[0335] For example, configuration information associated with the quality of the serving cell using L3 filtering may include information indicating one or more types of Layer 1 measurements to be used for L3 filtering.

[0336] In some representative embodiments, WTRU 102 may (e.g., implement a method to) receive information indicating an RRC reconfiguration message, which includes information indicating an LTM pause and a time period. WTRU 102 may (e.g., perform an RRC reconfiguration and) send an RRC reconfiguration complete message. WTRU 102 may receive an LTM handover command. WTRU 102 may send information indicating that an LTM handover command was not executed based on the time elapsed since receiving the RRC reconfiguration message being less than the time period or the time elapsed since transmitting the RRC reconfiguration complete message being less than the time period.

[0337] For example, WTRU 102 can stop LTM layer 1 reports based on receiving an LTM pause.

[0338] For example, information indicating that an LTM switching command was not executed could be a failure indication.

[0339] For example, a message indicating that the LTM switching command was not executed can be sent from the MAC CE.

[0340] For example, WTRU 102 can start LTM layer 1 reporting after the time elapsed since receiving the RRC reconfiguration message becomes greater than or equal to that time period.

[0341] For example, WTRU 102 can start LTM layer 1 reporting after the time elapsed since the transmission of the RRC reconfiguration completion message becomes greater than or equal to that time period.

[0342] In some representative embodiments, WTRU 102 may (e.g., implement a method to) receive information indicating the configuration of L3 measurement events and / or reports. WTRU 102 may receive information indicating LTM configuration. WTRU 102 may receive information indicating conditions for including PCell information in the L3 measurement report. WTRU 102 may perform measurements on the serving cell and candidate cells. WTRU 102 may send L1 / 2 measurement reports based on the measurements. The L1 / 2 measurement reports may include information indicating that the measurement results of the candidate cell are higher than the measurement results of the serving cell modified by (e.g., plus) an offset. After sending the L1 / 2 measurement reports, WTRU 102 may initiate the transmission of L3 measurement reports based on the triggering of an L3 measurement event. The L3 measurement reports may include information indicating the identifier of the PCell of WTRU 102 associated with the triggering of the L3 measurement event. WTRU 102 may receive LTM cell handover commands. WTRU 102 may be reconfigured to another cell based on the LTM cell handover commands. The WTRU 102 can transmit L3 measurement reports (e.g., after reconfiguration to another cell).

[0343] In some representative embodiments, WTRU 102 may receive RRC reconfiguration messages in the source cell (e.g., when connected to the source cell). WTRU 102 may apply the RRC reconfiguration information included in the RRC reconfiguration message. WTRU 102 may send an RRC reconfiguration complete message, which includes information indicating the identifier of the PCell of WTRU 102 and information indicating that the RRC reconfiguration complete message is only due to RRC reconfiguration.

[0344] In some representative embodiments, WTRU 102 may receive RRC reconfiguration messages in the source cell (e.g., when connected to the source cell). WTRU 102 may apply the RRC reconfiguration information included in the RRC reconfiguration message. WTRU 102 may receive LTM cell handover commands. WTRU 102 may reconfigure to another cell based on the LTM cell handover commands. WTRU 102 may send an RRC reconfiguration complete message, which includes information indicating the identifier of WTRU 102's PCell and information indicating that the RRC reconfiguration complete message is due to both RRC reconfiguration and LTM reconfiguration.

[0345] For example, LTM cell handover commands can be included in MAC CE.

[0346] For example, an RRC reconfiguration complete message includes any one of the message identifier, counter value, and / or security token associated with the RRC reconfiguration message.

[0347] Figure 16 This is a process diagram illustrating a second example LTM process according to certain representative embodiments. Figure 16In this configuration, WTRU 102 may (e.g., implement a method to) receive information at 1602 indicating configuration information for the active LTM set and the target LTM set. At 1604, WTRU 102 may receive information indicating measurement events associated with the serving cell (e.g., associated with the active LTM set) and / or neighboring cells (e.g., associated with the target LTM set). At 1606, WTRU 102 may determine the number of cells based on the time elapsed since the last LTM handover (e.g., performed). At 1608, WTRU 102 may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. At 1610, WTRU 102 may send a measurement report associated with the measurement event and / or perform a conditional reconfiguration based on (1) measurements of the serving cell modified by a first offset and / or (2) measurements of the neighboring cells modified by a second offset satisfying the measurement event. For example, the first offset may be based on measurements of the active LTM set (e.g., determined using measurements of the active LTM set). For example, the second offset may be based on measurements of the target LTM set (e.g., determined using measurements of the target LTM set).

[0348] Figure 17 This is a process diagram illustrating a third example LTM process according to certain representative embodiments. Figure 17 At 1702, WTRU 102 can receive information indicating configuration information associated with the quality of the serving cell using L3 filtering. At 1704, WTRU 102 can receive information indicating measurement events associated with the use of TTT periods and offsets (and / or scaling factors and / or thresholds). At 1706, WTRU 102 can determine, for the first serving cell and / or neighboring cells, that a measurement event is met during a first time period. The first time period may (e.g., is) be shorter than the TTT period. At 1708, WTRU 102 can receive information indicating that, at the end of the first time period, the first serving cell is switched to a second serving cell using LTM. At 1710, WTRU 102 can determine, for the second serving cell and / or neighboring cells, that a measurement event is met during a second time period. The sum of the first time period and the second time period may (e.g., is) be greater than or equal to the TTT period. WTRU 102 can send a measurement report at 1712 that includes information indicating the first serving cell, the second serving cell, and / or the first time period and the second time period, based on (1) the measurement result of the neighboring cell being greater than (2) the measurement result of the second serving cell plus an offset (or otherwise the measurement result of the second serving cell modified by the offset).

[0349] Figure 18 This is a process diagram illustrating a fourth example LTM process according to certain representative embodiments. Figure 18In step 1802, the WTRU may (e.g., implement a method to) receive information indicating an RRC reconfiguration message, which includes information indicating an LTM pause and a time period. At step 1804, the WTRU may (e.g., perform an RRC reconfiguration and) send an RRC reconfiguration complete message. At step 1806, the WTRU may receive an LTM handover command. At step 1808, the WTRU may send information indicating that the LTM handover command was not executed based on the time elapsed since receiving the RRC reconfiguration message being less than the time period or the time elapsed since transmitting the RRC reconfiguration complete message being less than the time period.

[0350] Figure 19 This is a process diagram illustrating a fifth example LTM process according to certain representative embodiments. Figure 19 At 1902, WTRU 102 can receive information indicating the configuration of L3 measurement events and / or reports. At 1904, WTRU 102 can receive information indicating LTM configuration. At 1906, WTRU 102 can receive information indicating the conditions for including primary cell (PCell) information in the L3 measurement report. At 1908, WTRU 102 can perform measurements on the serving cell and candidate cells. At 1910, WTRU 102 can send L1 / L2 measurement reports based on the measurements. The L1 / L2 measurement reports may include information indicating that the measurement results of the candidate cell are higher than the measurement results of the serving cell plus an offset. At 1912, WTRU 102 can begin the transmission of L3 measurement reports based on the triggering of an L3 measurement event after sending L1 / L2 measurement reports. The L3 measurement report may include information indicating the identifier of the WTRU's PCell associated with the triggering of the L3 measurement event. At 1914, WTRU 102 can receive LTM cell handover commands. At point 1916, WTRU 102 can be reconfigured to another cell based on LTM cell handover commands. At point 1918, WTRU 102 can complete the transmission of Layer 3 measurement reports.

[0351] Figure 20 This is a process diagram illustrating an example procedure for measurement reporting that uses the association between the serving cell's beam and the beams of other cells. Figure 20In section 2002, WTRU 102 can receive configuration information associated with determining LTM quality. The configuration information may include any of the following: (i) a minimum number of beams and / or cells used to determine LTM quality, (ii) offset and / or scaling information, (iii) association between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using LTM quality as serving cell quality or as an offset to serving cell quality. In section 2004, WTRU 102 can receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions. In section 2006, WTRU 102 can perform a first measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. In section 2008, WTRU 102 can use the first measurement and the configuration information associated with determining LTM quality to determine a first LTM quality. In 2020, the WTRU can send a report associated with an L1 / L3 measurement event based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. This report includes information indicating the quality of the first LTM.

[0352] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the target cell and one or more beams of other cells associated with the target cell. WTRU 102 can use the second measurement to determine a second LTM quality.

[0353] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

[0354] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison of the serving cell quality using a first LTM quality offset and / or scaling with (ii) a second LTM quality.

[0355] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the serving cell to determine the serving cell quality.

[0356] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the target cell. WTRU 102 can use the second measurement to determine the quality of the target cell.

[0357] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the target cell quality.

[0358] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison between the serving cell quality using a first LTM quality offset and / or scaling and (ii) the target cell quality.

[0359] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the serving cell to determine the serving cell quality.

[0360] In some representative embodiments, WTRU 102 may send reports to any of the serving cells or to one of the other cells associated with one or more beams of the serving cell.

[0361] In some representative embodiments, WTRU 102 may perform an LTM cell handover to a target cell based on the fulfillment of triggering conditions. For example, a report may be sent to the target cell.

[0362] In some representative embodiments, WTRU 102 can perform conditional reconfiguration based on the fulfillment of triggering conditions. For example, a report can be sent to the target cell.

[0363] Figure 21 This is a process diagram illustrating an example of a conditional reconfiguration process using the association of the serving cell's beam with the beams of other cells. Figure 21 At 2102, WTRU 102 may receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2). For example, the configuration information may include any of the following: (i) a minimum number of beams and / or cells used to determine the LTM quality, (ii) offset and / or scaling information, (iii) association between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the target cell quality or as an offset from the target cell quality. At 2104, WTRU 102 may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with the triggering condition. At 2106, WTRU 102 may perform a first measurement on one or more beams of the target cell and one or more beams of other cells associated with the target cell. At 2108, WTRU 102 may use the first measurement and the configuration information associated with the determined LTM quality to determine a first LTM quality. At 2110, WTRU 102 can send a report associated with an L1 / L3 measurement event based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. This report includes information indicating the quality of the first LTM.

[0364] In some representative embodiments, WTRU 102 may perform a second measurement of one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. WTRU 102 may use the second measurement to determine a second LTM quality.

[0365] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

[0366] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison of the target cell quality using a first LTM quality offset and / or scaling with (ii) a second LTM quality.

[0367] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the target cell to determine the quality of the target cell.

[0368] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the serving cell. WTRU 102 can use the second measurement to determine the quality of the serving cell.

[0369] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the serving cell quality.

[0370] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison between the target cell quality using a first LTM quality offset and / or scaling and (ii) the serving cell quality.

[0371] In some representative embodiments, WTRU 102 may send reports to any cell in the serving cell or to one of other cells associated with one or more beams of the serving cell.

[0372] In some representative embodiments, WTRU 102 may perform an LTM cell handover to a target cell based on the fulfillment of triggering conditions. WTRU 102 may send a report to the target cell.

[0373] Figure 22 This is a process diagram illustrating an example of a conditional reconfiguration process using the association of the target cell's beam with the beams of other cells. Figure 22At 2202, WTRU 102 may receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2). The configuration information may include any of the following: (i) a minimum number of beams and / or cells used to determine the LTM quality, (ii) offset and / or scaling information, (iii) association between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the serving cell quality or as an offset to the serving cell quality. At 2204, WTRU 102 may receive configuration information indicating an L1 or L3 (L1 / L3) measurement event associated with a triggering condition. At 2206, WTRU 102 may perform a first measurement of one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. At 2208, WTRU 102 may use the first measurement and the configuration information associated with determining the LTM quality to determine a first LTM quality. At 2210, WTRU 102 can perform a conditional reconfiguration associated with an L1 / L3 measurement event based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover.

[0374] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the target cell and one or more beams of other cells associated with the target cell. WTRU 102 can use the second measurement to determine a second LTM quality.

[0375] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

[0376] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison of the serving cell quality using a first LTM quality offset and / or scaling with (ii) a second LTM quality.

[0377] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the serving cell to determine the serving cell quality.

[0378] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the target cell. WTRU 102 can use the second measurement to determine the quality of the target cell.

[0379] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the target cell quality.

[0380] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison between the serving cell quality using a first LTM quality offset and / or scaling and (ii) the target cell quality.

[0381] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the serving cell to determine the serving cell quality.

[0382] In some representative embodiments, WTRU 102 may send a report including information indicating the first LTM quality after a conditional reconfiguration. For example, WTRU 102 may send the report to any cell in the serving cell or to one of other cells associated with one or more beams of the serving cell.

[0383] Figure 23 This is a process diagram illustrating an example of a conditional reconfiguration process using the association of the target cell's beam with the beams of other cells. Figure 23 At 2302, WTRU 102 may receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2). The configuration information may include any of the following: (i) a minimum number of beams and / or cells used to determine the LTM quality, (ii) offset and / or scaling information, (iii) association between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the target cell quality or as an offset from the target cell quality. At 2304, WTRU 102 may receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with the triggering condition. At 2306, WTRU 102 may perform a first measurement of one or more beams of the target cell and one or more beams of other cells associated with the target cell. At 2308, WTRU 102 may use the first measurement and the configuration information associated with determining the LTM quality to determine a first LTM quality. At 2310, WTRU 102 can perform a conditional reconfiguration associated with an L1 / L3 measurement event based on the fulfillment of trigger conditions and the minimum time period that has elapsed since the last LTM cell handover.

[0384] In some representative embodiments, WTRU 102 may perform a second measurement of one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. WTRU 102 may use the second measurement to determine a second LTM quality.

[0385] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

[0386] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison of the target cell quality using a first LTM quality offset and / or scaling with (ii) a second LTM quality.

[0387] In some representative embodiments, WTRU 102 may use a first measurement of one or more beams of the target cell to determine the quality of the target cell.

[0388] In some representative embodiments, WTRU 102 can perform a second measurement of one or more beams of the serving cell. WTRU 102 can use the second measurement to determine the quality of the serving cell.

[0389] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the serving cell quality.

[0390] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on (i) a comparison between the target cell quality using a first LTM quality offset and / or scaling and (ii) the serving cell quality.

[0391] In some representative embodiments, WTRU 102 may send a report including information indicating the first LTM quality after a conditional reconfiguration. For example, the report may be sent to any cell in the serving cell or one of other cells associated with one or more beams of the serving cell.

[0392] Figure 24 This is a process diagram illustrating an example procedure for measurement reporting using both the active LTM set and the target LTM set. Figure 24 At 2402, WTRU 102 can receive configuration information associated with the active LTM set and the target LTM set. At 2404, WTRU 102 can receive configuration information indicating measurement events associated with trigger conditions for the serving cell and / or neighboring cells. At 2406, WTRU 102 can determine the number of cells in the active LTM set and / or the number of cells in the target LTM set based on the time elapsed since the last LTM handover. At 2408, WTRU 102 can perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. At 2410, WTRU 102 can send a measurement report associated with the measurement event based on the fact that the trigger conditions are met using (1) the quality of the serving cell modified by a first offset and / or (2) the quality of the neighboring cells modified by a second offset.

[0393] In some representative embodiments, WTRU 102 may determine the number of additional cells as a first value based on the time elapsed since the last LTM handover being less than a threshold, or determine the number of additional cells as a second value based on the time elapsed since the last LTM handover being greater than a threshold.

[0394] In some representative embodiments, WTRU 102 may determine the number of cells in an active LTM set based on one or more criteria, and / or select the number of cells in a target LTM set based on one or more criteria.

[0395] In some representative embodiments, one or more criteria for determining the number of cells in an active LTM set may include any one of the following: (i) cells in an active LTM set with which the WTRU has downlink synchronization, (ii) cells in an active LTM set with which the WTRU has uplink synchronization, (iii) cells in an active LTM set with which the WTRU is configured to report channel state information, (iv) cells in an active LTM set with which the WTRU is configured to perform tracking reference signal (TRS) tracking, and / or (v) cells in an active LTM set with a measured radio quality above a threshold.

[0396] In some representative embodiments, WTRU 102 may determine a first offset based on the number of cells in the active LTM set and / or determine a second offset based on the number of cells in the target LTM set that meet a threshold.

[0397] In some representative embodiments, WTRU 102 may determine a first offset based on measurements of the active LTM set, and / or determine a second offset based on measurements of the target LTM set.

[0398] In some representative embodiments, the measurement report may include information indicating the determined number of cells and / or the cells associated with triggering the measurement event.

[0399] In some representative embodiments, WTRU 102 may determine a first offset based on measurements of an active LTM set that meets one or more criteria, and / or determine a second offset based on measurements of a target LTM set that meets one or more criteria.

[0400] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a first condition that compares the quality of the serving cell with the quality of neighboring cells.

[0401] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of the neighboring cell modified by the second offset with a threshold.

[0402] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of the serving cell with a first threshold and a third condition that compares the quality of the neighboring cell modified by the second offset with the second threshold.

[0403] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of neighboring cells modified by the second offset with a first threshold and a third condition that compares the number of cells in the target LTM set that meet the second and third thresholds.

[0404] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of neighboring cells modified by the second offset with a first threshold and a third condition that compares the number of cells in the active LTM set with the second threshold.

[0405] In some representative embodiments, WTRU 102 may determine whether a trigger condition is met based on a first condition that compares the quality of each cell in the target LTM set with a first threshold and a second condition that compares the number of cells that meet the first condition with a second threshold.

[0406] Figure 25 This is a process diagram illustrating an example of a conditional reconfiguration process using an active LTM set and a target LTM set. Figure 25 At 2502, WTRU 102 may receive configuration information associated with the active LTM set and the target LTM set. At 2504, WTRU 102 may receive configuration information indicating measurement events associated with trigger conditions for the serving cell and / or neighboring cells. At 2506, WTRU 102 may determine the number of cells in the active LTM set and / or the number of cells in the target LTM set based on the time elapsed since the last LTM handover. At 2508, WTRU 102 may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. At 2510, WTRU 102 may perform conditional reconfiguration based on the fact that the trigger conditions are met using (1) the quality of the serving cell modified by a first offset and / or (2) the quality of the neighboring cells modified by a second offset.

[0407] In some representative embodiments, WTRU 102 may determine the number of additional cells as a first value based on the time elapsed since the last LTM handover being less than a threshold, or determine the number of additional cells as a second value based on the time elapsed since the last LTM handover being greater than a threshold.

[0408] In some representative embodiments, WTRU 102 may determine the number of cells in an active LTM set based on one or more criteria, and / or select the number of cells in a target LTM set based on one or more criteria.

[0409] In some representative embodiments, one or more criteria for determining the number of cells in an active LTM set may include any one of the following: (i) cells in an active LTM set with which the WTRU has downlink synchronization, (ii) cells in an active LTM set with which the WTRU has uplink synchronization, (iii) cells in an active LTM set with which the WTRU is configured to report channel state information, (iv) cells in an active LTM set with which the WTRU is configured to perform tracking reference signal (TRS) tracking, and / or (v) cells in an active LTM set with a measured radio quality above a threshold.

[0410] In some representative embodiments, WTRU 102 may determine a first offset based on the number of cells in the active LTM set and / or determine a second offset based on the number of cells in the target LTM set that meet a threshold.

[0411] In some representative embodiments, WTRU 102 may determine a first offset based on measurements of the active LTM set, and / or determine a second offset based on measurements of the target LTM set.

[0412] In some representative embodiments, WTRU 102 may send a measurement report associated with conditional reconfiguration, which includes information indicating the determined number of cells or cells and / or cells associated with triggering the measurement event.

[0413] In some representative embodiments, WTRU 102 may determine a first offset based on measurements of an active LTM set that meets one or more criteria, and / or determine a second offset based on measurements of a target LTM set that meets one or more criteria.

[0414] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a first condition that compares the quality of the serving cell with the quality of neighboring cells.

[0415] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of the neighboring cell modified by the second offset with a threshold.

[0416] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of the serving cell with a first threshold and a third condition that compares the quality of the neighboring cell modified by the second offset with the second threshold.

[0417] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of neighboring cells modified by the second offset with a first threshold and a third condition that compares the number of cells in the target LTM set that meet the second and third thresholds.

[0418] In some representative embodiments, WTRU 102 may determine whether the triggering condition is met based on a second condition that compares the quality of neighboring cells modified by the second offset with a first threshold and a third condition that compares the number of cells in the active LTM set with the second threshold.

[0419] In some representative embodiments, WTRU 102 may determine whether a triggering condition is met based on a first condition that compares the quality of each cell in the target LTM set with a first threshold and a second condition that compares the number of cells that meet the first condition with a second threshold.

[0420] Figure 26 This is a process diagram illustrating an example procedure for measurement reporting using a trigger time (TTT) period. Figure 26 At 2602, WTRU 102 can receive configuration information associated with determining cell quality using L3 filtering. At 2604, WTRU 102 can receive configuration information indicating measurement events associated with a trigger time period (TTT) and offset. At 2606, WTRU 102 can determine, based on a first triggering condition, that a measurement event is satisfied at the beginning of a first time period using the quality of the first serving cell and the quality of neighboring cells using L3 filtering. At 2608, WTRU 102 can receive information indicating a handover of the first serving cell to a second serving cell using Layer 1 / Layer 2 triggered mobility (LTM) at the end of the first time period, wherein the first time period is shorter than the TTT period. At 2610, WTRU 102 can determine the satisfaction of a measurement event based on a second triggering condition, during a second time period, based on the quality of the second serving cell and the quality of neighboring cells during the second time period using L3 filtering, wherein the second time period is after the first time period, and the sum of the first and second time periods is greater than or equal to the TTT period. At 2612, WTRU102 can send a measurement report based on the measurement result that the quality of the neighboring cell is greater than that of the second serving cell plus an offset. The measurement report includes information indicating any of the following: (i) the first serving cell and the second serving cell, and / or (ii) the first time period and the second time period.

[0421] In some representative embodiments, WTRU 102 may perform a handover from the first serving cell to the second serving cell at the end of the first time period.

[0422] In some representative embodiments, the second time period may begin when switching to the second serving cell.

[0423] In some representative embodiments, WTRU 102 can determine a first plurality of L1 measurements of one or more reference signals from the first serving cell. WTRU 102 can use L3 filtering of the first plurality of L1 measurements to determine the quality of the first serving cell.

[0424] In some representative embodiments, WTRU 102 can determine a second plurality of layer (L1) measurements of one or more reference signals from the second serving cell. WTRU 102 can use L3 filtering of the second plurality of L1 measurements and the first plurality of L1 measurements to determine the quality of the second serving cell.

[0425] In some representative embodiments, the measurement report may include information indicating the determined quality of the second serving cell.

[0426] In some representative embodiments, WTRU 102 can determine a third plurality of L1 measurements of one or more reference signals from neighboring cells. WTRU 102 can use the third plurality of L1 measurements to determine the quality of the neighboring cells.

[0427] In some representative embodiments, the WTRU 102 may use L3 filtering based on a third plurality of L1 measurements to determine the quality of neighboring cells.

[0428] In some representative embodiments, configuration information associated with the quality of the serving cell using L3 filtering may include information indicating one or more filter coefficients, one or more reference signal types, and / or any one of one or more reference signal indices. WTRU 102 may perform corresponding L1 measurements based on the reference signal type and / or reference signal index, and / or perform L3 filtering based on the filter coefficients.

[0429] In some representative embodiments, information indicating the use of LTM to switch from the first serving cell to the second serving cell is included in the MAC CE.

[0430] In some representative embodiments, the measurement report may include information indicating the quality of the second serving cell and / or the quality of the first serving cell.

[0431] In some representative embodiments, WTRU 102 can perform L3 filtering on any of the following measurements: reference signal received power (RSRP), reference signal received quality (RSRQ), or signal-to-interference-plus-noise ratio (SINR).

[0432] Figure 27 This is a process diagram illustrating an example procedure for LTM measurement pause and measurement reporting. Figure 27 At 2702, WTRU 102 can receive an RRC reconfiguration message, which includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). At 2704, WTRU 102 can send an RRC reconfiguration complete message. At 2706, WTRU 102 can receive an LTM switching command. At 2708, WTRU 102 can send information indicating that an LTM switching command will not be executed based on the time elapsed since receiving the RRC reconfiguration message being less than the indicated time period. At 2710, WTRU 102 can send an LTM measurement report based on the time elapsed since receiving the RRC reconfiguration message being greater than the indicated time period.

[0433] In some representative embodiments, WTRU 102 may stop LTM measurement reporting based on the indicated LTM pause when the time elapsed since receiving the RRC reconfiguration message is less than the indicated time period.

[0434] In some representative embodiments, the information indicating that the LTM switching command was not executed can be a failure indication.

[0435] In some representative embodiments, a message indicating that the LTM switching command was not executed is sent in the MAC CE.

[0436] In some representative embodiments, WTRU 102 may send an LTM measurement report before receiving an RRC reconfiguration message.

[0437] Figure 28 This is a process diagram illustrating another example of a process used for LTM measurement pauses and measurement reporting. Figure 28 At 2802, WTRU 102 can receive an RRC reconfiguration message, which includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). At 2804, WTRU 102 can send an RRC reconfiguration complete message. At 2806, WTRU 102 can receive an LTM switching command. At 2808, WTRU 102 can send information indicating that the LTM switching command will not be executed based on the time elapsed since the transmission of the RRC reconfiguration complete message being less than the indicated time period. At 2810, WTRU 102 can send an LTM measurement report based on the time elapsed since receiving the RRC reconfiguration message being greater than the indicated time period.

[0438] In some representative embodiments, WTRU 102 may stop LTM measurement reporting based on the indicated LTM pause when the time elapsed since receiving the RRC reconfiguration message is less than the indicated time period.

[0439] In some representative embodiments, the information indicating that the LTM switching command was not executed can be a failure indication.

[0440] In some representative embodiments, a message indicating that the LTM switching command was not executed is sent in the MAC CE.

[0441] In some representative embodiments, WTRU 102 may send an LTM measurement report before receiving an RRC reconfiguration message.

[0442] Figure 29 This is a process diagram illustrating yet another example of a process for LTM measurement pauses and measurement reporting. Figure 29 At 2902, WTRU 102 can receive an RRC reconfiguration message, which includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). At 2904, WTRU 102 can send an RRC reconfiguration complete message. At 2906, WTRU 102 can receive an LTM switching command. At 2908, WTRU 102 can send information indicating that the LTM switching command will not be executed based on the time elapsed since receiving the RRC reconfiguration message being less than the indicated time period. At 2910, WTRU 102 can send an LTM measurement report based on the time elapsed since sending the RRC reconfiguration complete message being greater than the indicated time period.

[0443] In some representative embodiments, WTRU 102 may stop LTM measurement reporting based on the indicated LTM pause when the time elapsed since sending the RRC reconfiguration complete message is less than the indicated time period.

[0444] In some representative embodiments, the information indicating that the LTM switching command was not executed can be a failure indication.

[0445] In some representative embodiments, a message indicating that the LTM switching command was not executed is sent in the MAC CE.

[0446] In some representative embodiments, WTRU 102 may send an LTM measurement report before receiving an RRC reconfiguration message.

[0447] Figure 30 This is a process diagram illustrating yet another example of a process for LTM measurement pauses and measurement reporting. Figure 30In the above steps, at 3002, WTRU 102 can receive an RRC reconfiguration message, which includes information indicating an LTM measurement pause and a time period (e.g., associated with an LTM pause). At 3004, WTRU 102 can send an RRC reconfiguration complete message. At 3006, WTRU 102 can receive an LTM handover command. At 3008, WTRU 102 can send information indicating that an LTM handover command will not be executed based on the time elapsed since the transmission of the RRC reconfiguration complete message being less than the indicated time period. At 3010, WTRU 102 can send an LTM measurement report based on the time elapsed since the transmission of the RRC reconfiguration complete message being greater than the indicated time period.

[0448] In some representative embodiments, WTRU 102 may stop LTM measurement reporting based on the indicated LTM pause when the time elapsed since sending the RRC reconfiguration complete message is less than the indicated time period.

[0449] In some representative embodiments, the information indicating that the LTM switching command was not executed can be a failure indication.

[0450] In some representative embodiments, a message indicating that the LTM switching command was not executed is sent in the MAC CE.

[0451] In some representative embodiments, WTRU 102 may send an LTM measurement report before receiving an RRC reconfiguration message.

[0452] Figure 31 This is a process diagram illustrating an example procedure for LTM switching and measurement reporting. Figure 31At 3102, WTRU 102 can receive information indicating the configuration of L3 measurement events and / or reports. At 3104, WTRU 102 can receive information indicating LTM configuration. At 3106, WTRU 102 can receive information indicating conditions for including primary cell (PCell) information in the L3 measurement report. At 3108, WTRU 102 can perform measurements on the serving cell and candidate cells. At 3110, WTRU 102 can send L1 / L2 measurement reports based on measurements, wherein the L1 / L2 measurement reports include information indicating (i) the measurement result of the candidate cell is higher than (ii) the measurement result of the serving cell plus an offset. At 3112, WTRU 102 can initiate the transmission of L3 measurement reports based on the triggering of an L3 measurement event after sending L1 / L2 measurement reports. The L3 measurement report may include information indicating the identifier of the PCell of the WTRU associated with the triggering of the L3 measurement event. At 3114, WTRU 102 can receive LTM cell handover commands. At 3116, WTRU 102 can be reconfigured to another cell based on LTM cell handover commands. At 3118, WTRU 102 can complete the transmission of L3 measurement reports.

[0453] In some representative embodiments, the condition may be (i) the measurement result of the candidate cell is higher than (ii) the measurement result of the serving cell plus an offset.

[0454] In some representative embodiments, the LTM cell handover command can be received after the transmission of the L3 measurement report has begun.

[0455] In some representative embodiments, LTM cell handover commands can be received before the transmission of L3 measurement reports is completed.

[0456] In some representative embodiments, the transmission of L3 measurement reports can be completed after reconfiguration to another cell.

[0457] Figure 32 This is a process diagram illustrating an example procedure for LTM handover and RRC signaling. Figure 32 At 3202, WTRU 102 can receive an RRC reconfiguration message in the source cell (e.g., from the source cell). At 3204, WTRU 102 can apply the RRC reconfiguration information included in the RRC reconfiguration message. At 3206, WTRU 102 can send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is due to an RRC reconfiguration.

[0458] In some representative embodiments, the RRC reconfiguration complete message may include information indicating that the RRC reconfiguration complete message is only due to RRC reconfiguration.

[0459] In some representative embodiments, the identifier of the PCell of the WTRU may be the Physical Cell Identifier (PCI).

[0460] Figure 33 This is a process diagram illustrating another example procedure for LTM handover and RRC signaling. Figure 33 In step 3302, WTRU 102 can receive an RRC reconfiguration message in the source cell (e.g., from the source cell). At step 3304, WTRU 102 can apply the RRC reconfiguration information included in the RRC reconfiguration message. At step 3306, WTRU 102 can receive an LTM cell handover command. At step 3308, WTRU 102 can reconfigure to another cell based on the LTM cell handover command. At step 3310, WTRU 102 can send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is due to both RRC and LTM reconfiguration.

[0461] In some representative embodiments, LTM cell handover commands may be included in the MAC CE.

[0462] In some representative embodiments, the RRC reconfiguration complete message may include any one of the message identifier, counter value, and / or security token associated with the RRC reconfiguration message.

[0463] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving information indicating configuration information associated with the quality of LTM. WTRU 102 may receive information indicating measurement events. WTRU 102 may determine the quality of a first LTM set based on measurements of a first set of beams from a first plurality of cells. WTRU 102 may send a measurement report associated with the measurement event and / or perform a conditional reconfiguration based on (1) the determined quality using the first LTM set satisfies the measurement event and (2) the time elapsed since the last LTM cell handover.

[0464] For example, WTRU 102 can determine the quality of a second LTM set based on measurements of a second set of beams from a second plurality of cells. Measurement events can be determined to be satisfied using the quality determined by the first LTM set and the quality determined by the second LTM set.

[0465] For example, WTRU 102 may define a first set of beams as a subset of multiple beams from a first plurality of cells and / or define a second set of beams as a subset of multiple beams from a second plurality of cells.

[0466] For example, WTRU 102 can determine the quality of a serving cell or target cell outside the first LTM set. WTRU 102 can determine the quality determined using the first LTM set and the quality determined for the serving or target cell to satisfy a measurement event.

[0467] For example, WTRU 102 can perform the final LTM switch before the measurement event is met.

[0468] For example, WTRU 102 can send a measurement report including information indicating the determined quality of the first LTM set, and / or conditionally reconfigure to include sending information indicating the determined quality of the first LTM set.

[0469] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving information indicating configuration information for an active LTM set and a target LTM set. WTRU 102 may receive information indicating measurement events associated with the serving cell and / or neighboring cells. WTRU 102 may determine the number of cells based on the time elapsed since the last LTM handover. WTRU 102 may perform measurements on the number of cells in the active LTM set and the number of cells in the target LTM set. WTRU 102 may send measurement reports associated with measurement events and / or perform conditional reconfiguration based on measurements of the serving cell modified by a first offset and / or measurements of neighboring cells modified by a second offset. The first offset may be based on measurements of the active LTM set, and / or the second offset may be based on measurements of the target LTM set.

[0470] For example, WTRU 102 can determine the number of additional cells as a first value based on the time elapsed since the last LTM handover being less than a threshold, or determine the number of additional cells as a second value based on the time elapsed since the last LTM handover being greater than a threshold.

[0471] For example, WTRU 102 can select the number of cells in an active LTM set based on one or more criteria, and / or select the number of cells in a target LTM set based on one or more criteria.

[0472] For example, WTRU 102 may send a measurement report including information indicating the determined number or cells and / or cells associated with the triggering measurement event, and / or performing conditional reconfiguration may include sending information indicating the determined number or cells and / or cells associated with the triggering measurement event.

[0473] For example, WTRU 102 can determine a first offset based on measurements of an active LTM set that meets one or more criteria, and / or determine a second offset based on measurements of a target LTM set that meets one or more criteria.

[0474] For example, the final LTM handover could be the handover of the final LTM candidate cell.

[0475] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving information indicating a configuration associated with the quality of the serving cell using L3 filtering. WTRU 102 may receive information indicating measurement events associated with a trigger time to trigger (TTT) period and an offset. WTRU 102 may determine that a measurement event is met for a first serving cell and / or a neighboring cell during a first time period. The first time period is shorter than the TTT period. WTRU 102 may receive information indicating a handover of the first serving cell to a second serving cell using LTM at the end of the first time period. WTRU 102 may determine that a measurement event is met for the second serving cell and / or a neighboring cell during a second time period. The sum of the first time period and the second time period is greater than or equal to the TTT period. WTRU 102 may send a measurement report including information indicating the first serving cell, the second serving cell, and / or the first time period and the second time period, based on the fact that the measurement result of the neighboring cell is greater than the measurement result of the second serving cell plus an offset.

[0476] For example, for the first serving cell using Layer 3 filtering and / or neighboring cells using Layer 3 filtering, WTRU 102 can determine that a measurement event is met during a first time period.

[0477] For example, for the first serving cell using Layer 3 filtering and / or the neighboring cells using Layer 3 filtering, WTRU 102 can determine that a measurement event is met during the second time period.

[0478] For example, the MAC CE receives information instructing the user to switch from the first serving cell to the second serving cell.

[0479] For example, configurations associated with the quality of the serving cell using L3 filtering may include information indicating one or more filter coefficients for L3 filtering and / or one or more reference signals for L3 filtering.

[0480] For example, configurations associated with the quality of the serving cell using L3 filtering may include information indicating one or more types of L1 measurements to be used for L3 filtering.

[0481] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving information indicating an RRC reconfiguration message, the RRC reconfiguration message including information indicating an LTM pause and a time period. WTRU 102 may send an RRC reconfiguration complete message. WTRU 102 may (e.g., then) receive an LTM switching command. WTRU 102 may (e.g., then) send information indicating that the LTM switching command was not executed based on the time elapsed since receiving the RRC reconfiguration message being less than the time period or the time elapsed since transmitting the RRC reconfiguration complete message being less than the time period.

[0482] For example, WTRU 102 can stop LTM L1 reporting based on receiving an LTM pause.

[0483] For example, information indicating that an LTM switching command was not executed could be a failure indication.

[0484] For example, a message indicating that the LTM switching command was not executed is sent in the MAC CE.

[0485] For example, WTRU 102 can start LTM L1 reporting after the time elapsed since receiving the RRC reconfiguration message becomes greater than or equal to that time period.

[0486] For example, WTRU 102 can start LTM L1 reporting after the time elapsed since the transmission of the RRC reconfiguration completion message becomes greater than or equal to that time period.

[0487] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving information indicating configuration for L3 measurement events and / or reports. WTRU 102 may receive information indicating LTM configuration. WTRU 102 may receive information indicating conditions for including primary cell (PCell) information in the L3 measurement report. WTRU 102 may perform measurements on the serving cell and candidate cells. WTRU 102 may send L1 / L2 measurement reports based on the measurements. The L1 / L2 measurement reports include information indicating that the measurement result of the candidate cell is higher than the measurement result of the serving cell plus an offset. After sending the L1 / L2 measurement reports, WTRU 102 may initiate the transmission of L3 measurement reports based on the triggering of an L3 measurement event. The L3 measurement report includes information indicating the identifier of the PCell of WTRU 102 associated with the triggering of the L3 measurement event. WTRU 102 may receive LTM cell handover commands. WTRU 102 may be reconfigured to another cell based on the LTM cell handover commands. The WTRU 102 can (for example, then) complete the transmission of L3 measurement reports.

[0488] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving RRC reconfiguration messages in the source cell. WTRU 102 may apply RRC reconfiguration information included in the RRC reconfiguration message. WTRU 102 may send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is solely due to the RRC reconfiguration.

[0489] In some representative embodiments, WTRU 102 may be configured (e.g., to implement a method) to include receiving RRC reconfiguration messages in (e.g., from) a source cell. WTRU 102 may apply RRC reconfiguration information included in the RRC reconfiguration message. WTRU 102 may receive LTM cell handover commands. WTRU 102 may reconfigure to another cell based on the LTM cell handover commands. WTRU 102 may send an RRC reconfiguration complete message, which includes information indicating the identifier of the WTRU's PCell and information indicating that the RRC reconfiguration complete message is due to both RRC reconfiguration and LTM reconfiguration.

[0490] For example, LTM cell handover commands can be included in MAC CE.

[0491] For example, an RRC reconfiguration complete message may include any one of the message identifier, counter value, and / or security token associated with the RRC reconfiguration message.

[0492] in conclusion While features and elements have been provided above in specific combinations, those skilled in the art will understand that each feature or element can be used alone or in any combination with other features and elements. This disclosure is not limited to the specific embodiments described herein, which are intended as illustrative of various aspects. It will be apparent to those skilled in the art that many modifications and variations can be made without departing from its spirit and scope. Elements, actions, or instructions not used in the description herein should be construed as critical or essential to the invention unless expressly provided so. Based on the foregoing description, functionally equivalent methods and apparatus within the scope of this disclosure, in addition to those listed herein, will be apparent to those skilled in the art. Such modifications and variations are intended to fall within the scope of the appended claims. This disclosure is limited only by the terminology of the appended claims and the full scope of equivalents conferred by such claims. It should be understood that this disclosure is not limited to specific methods or systems.

[0493] For simplicity, the foregoing embodiments have been discussed in terms of terminology and structure relating to devices with wireless communication capabilities (e.g., radio wave transmitters and receivers). However, the embodiments discussed are not limited to these systems, but can be applied to other systems that use other forms of electromagnetic waves or non-electromagnetic waves such as sound waves.

[0494] It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the term "video" or the term "image" may mean any one of a snapshot, a single image, and / or multiple images displayed on a time-based basis. As another example, when referred to herein, the term "user equipment" and its abbreviation "UE," the term "remote," and / or the term "head-mounted display" or its abbreviation "HMD" may represent or include (i) a wireless transmitting and / or receiving unit (WTRU); (ii) any embodiment of a plurality of embodiments of a WTRU; (iii) a device particularly configured with some or all of the structural and functional aspects of a WTRU having wireless and / or wire capabilities (e.g., tetherable); (iv) a device configured with fewer than all the structural and functional aspects of a WTRU having wireless and / or wire capabilities; or (iv) something like that. Figure 1A-1DDetails of an example WTRU are provided, which may represent any WTRU described herein. As another example, the various embodiments disclosed above and below are described as utilizing a head-mounted display. Those skilled in the art will recognize that devices other than head-mounted displays can be utilized, and some or all of the embodiments disclosed herein and the various disclosures can be modified accordingly without excessive experimentation. Examples of such other devices may include drones or other devices configured to stream information for providing an adaptive reality experience.

[0495] Furthermore, the methods described herein can be implemented in computer programs, software, or firmware incorporated in a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROMs and digital versatile discs (DVDs). The processor associated with the software can be used to implement a radio frequency transceiver used in a WTRU, UE, terminal, base station, RNC, or any host computer.

[0496] Variations of the methods, apparatus, and systems provided above are possible without departing from the scope of the invention. Given the many possible embodiments, it should be understood that the illustrated embodiments are merely examples and should not be construed as limiting the scope of the appended claims. For example, embodiments provided herein include handheld devices that may include any suitable voltage source providing any suitable voltage, such as a battery, and the like or used therewith.

[0497] Furthermore, in the embodiments provided above, note the processing platform, computing system, controller, and other devices including the processor. These devices may include at least one central processing unit (“CPU”) and memory. According to the practice of those skilled in the art of computer programming, references to actions and symbolic representations of operations or instructions can be executed by various CPUs and memories. Such actions and operations or instructions may be referred to as being “executed,” “computer-executed,” or “CPU-executed.”

[0498] Those skilled in the art will understand that the actions and symbols representing operations or instructions include manipulation of electrical signals by the CPU. The electrical system represents data bits that can cause a transformation or reduction of electrical signals and the maintenance of data bits at memory locations in a memory system, thereby reconfiguring or otherwise altering CPU operations and other signal processing. The memory location maintaining the data bits is a physical location having specific electrical, magnetic, optical, or organic properties corresponding to or representing the data bits. It should be understood that the embodiments are not limited to the platforms or CPUs described above, and other platforms and CPUs may support the provided methods.

[0499] Data bits may also be maintained on a computer-readable medium, including disks, optical disks, and any other volatile (e.g., random access memory (RAM)) or non-volatile (e.g., read-only memory (ROM)) mass storage system readable by a CPU. The computer-readable medium may include cooperative or interconnected computer-readable media that reside exclusively on the processing system or are distributed across multiple interconnected processing systems, either locally or remotely. It should be understood that the embodiments are not limited to the aforementioned memories, and other platforms and memories may support the provided methods.

[0500] In the illustrative embodiments, any operations, processes, etc., described herein may be implemented as computer-readable instructions stored on a computer-readable medium. These computer-readable instructions may be executed by a processor of a mobile unit, network element, and / or any other computing device.

[0501] There is little difference between the hardware and software implementations of the various aspects of the system. The use of hardware or software is often (but not always, as the choice between hardware and software may become important in certain contexts) a design choice representing a cost-efficiency trade-off. Various vehicles (e.g., hardware, software, and / or firmware) may exist through which the processes and / or systems and / or other technologies described herein can be implemented, and the preferred vehicle may vary depending on the context in which the processes and / or systems and / or other technologies are deployed. For example, if the implementer determines that speed and accuracy are paramount, the implementer may choose a predominantly hardware and / or firmware vehicle. If flexibility is paramount, the implementer may choose a predominantly software implementation. Alternatively, the implementer may choose some combination of hardware, software, and / or firmware.

[0502] The foregoing detailed description has illustrated various embodiments of the apparatus and / or processes using block diagrams, flowcharts, and / or examples. As such block diagrams, flowcharts, and / or examples encompass one or more functions and / or operations, those skilled in the art will understand that each function and / or operation within such block diagrams, flowcharts, or examples can be implemented individually and / or collectively through a wide range of hardware, software, firmware, or virtually any combination thereof. In embodiments, several portions of the subject matter described herein can be implemented via application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), digital signal processors (DSPs), and / or other forms of integration. However, those skilled in the art will recognize that some aspects of the embodiments disclosed herein can be implemented, in whole or in part, equivalently in an integrated circuit as one or more computer programs running on one or more computers (e.g., implemented as one or more programs running on one or more computer systems), implemented as one or more programs running on one or more processors (e.g., implemented as one or more programs running on one or more microprocessors), implemented as firmware, or virtually implemented as any combination thereof, and that designing circuitry and / or writing code for software and / or firmware in accordance with this disclosure will be well within the skill of those skilled in the art. Furthermore, those skilled in the art will understand that the mechanisms of the subject matter described herein can be distributed as various forms of program products, and that the illustrative embodiments of the subject matter described herein are applicable regardless of the specific type of signal-bearing medium used to actually perform the distribution. Examples of signal-bearing media include, but are not limited to, the following: recordable media, such as floppy disks, hard disk drives, CDs, DVDs, digital tapes, computer memory, etc.; and transmission media, such as digital and / or analog communication media (e.g., fiber optic cables, waveguides, wired communication links, wireless communication links, etc.).

[0503] Those skilled in the art will recognize that devices and / or processes are typically described in the manner set forth herein, and that such described devices and / or processes are subsequently integrated into data processing systems using engineering practice. That is, at least a portion of the devices and / or processes described herein can be integrated into a data processing system through a reasonable number of experiments. Those skilled in the art will recognize that a typical data processing system typically includes one or more of the following: a system unit housing, a video display device, memory such as volatile and non-volatile memory, a processor such as a microprocessor and a digital signal processor, a computing entity such as an operating system, drivers, a graphical user interface, and applications, one or more interactive devices such as a touchpad or screen, and / or a control system including feedback loops and control motors (e.g., feedback for sensing position and / or speed, control motors for moving and / or adjusting components and / or quantities). A typical data processing system can be implemented using any suitable commercially available components, such as those commonly found in data computing / communication and / or network computing / communication systems.

[0504] The topics described herein sometimes illustrate different components included within or connected to different other components. It should be understood that such depicted architectures are merely examples, and many other architectures can actually be implemented to achieve the same functionality. Conceptually, any arrangement of components achieving the same functionality is effectively “associated” to enable the desired functionality. Therefore, any two components combined herein to achieve a particular functionality can be considered “associated” with each other to enable the desired functionality, regardless of the architecture or intermediate components. Similarly, any two components so associated can also be considered “operably connected” or “operably coupled” to each other to achieve the desired functionality, and any two components that can be so associated can also be considered “operably coupled” to each other to achieve the desired functionality. Specific examples of operational coupling include, but are not limited to, physically matable and / or physically interactive components and / or wirelessly interactive and / or logically interactive and / or logically interactive components.

[0505] Regarding the use of virtually any plural and / or singular terms in this document, those skilled in the art can convert from plural to singular and / or from singular to plural as appropriate to the context and / or application. For clarity, various singular / plural permutations may be explicitly described herein.

[0506] Those skilled in the art will understand that, in general, the terms used herein, and especially in the appended claims (e.g., the body of the appended claims), are intended to be “open-ended” terms (e.g., the term “comprising” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “including” should be interpreted as “including but not limited to,” etc.). Those skilled in the art will further understand that if a specific number of items is intended to be described in the claims, such intention will be explicitly stated in the claims, and without such a statement, such intention does not exist. For example, the term “single” or similar language may be used where only one item is intended. To aid understanding, the appended claims and / or the description herein may include the use of introductory phrases “at least one” and “one or more” to introduce the recitation of the claims. However, the use of such phrases should not be construed as implying that a claim introduced by the indefinite article "a" or "an" limits any particular claim to include only one such embodiment, even when the same claim includes the introductory phrase "one or more" or "at least one" along with an indefinite article such as "a" or "an" (e.g., "a" and / or "an" should be interpreted as meaning "at least one" or "one or more"). The same applies to the use of definite articles for introducing claim recitations. Furthermore, even if a specific number of introductory claim recitations are explicitly stated, those skilled in the art will recognize that such a statement should be interpreted as meaning at least the number stated (e.g., a bare recitation of "two recitations" means at least two recitations, or two or more recitations, in the absence of other modifiers). Furthermore, in cases where conventions such as "at least one of A, B, and C" are used, such a construction is generally contemplated in the sense that a person skilled in the art would understand the convention to be in (e.g., "a system having at least one of A, B, and C" would include, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C). In cases where conventions such as "at least one of A, B, or C" are used, such a construction is generally contemplated in the sense that a person skilled in the art would understand the convention to be in (e.g., "a system having at least one of A, B, or C" would include, but is not limited to, systems having only A, only B, only C, both A and B, both A and C, both B and C, and / or both A, B, and C). A person skilled in the art will further understand that any extractive words and / or phrases that actually present two or more alternative terms, whether in the specification, claims, or drawings, should be understood to contemplate the possibility of including one, any one, or both of the terms. For example, the phrase “A or B” would be understood to include the possibility of “A” or “B” or “A and B”.Furthermore, as used herein, the term “any one of…” following a list of multiple items and / or categories of items is intended to individually or in combination with other items and / or other item categories to include “any one of…”, “any combination of…”, “any multiple of…”, and / or “any combination of multiple of…”. Additionally, as used herein, the term “set” is intended to include any number of items, including zero. Furthermore, as used herein, the term “quantity” is intended to include any quantity, including zero. And as used herein, the term “multiple” is intended to be synonymous with “multiple”.

[0507] Furthermore, when the features or aspects of this disclosure are described in accordance with the Markush Group, those skilled in the art will recognize that this disclosure is also described in accordance with any individual member or subgroup of the Markush Group.

[0508] As those skilled in the art will understand, for any and all purposes, such as in providing a written description, all scopes disclosed herein also encompass any and all possible subscopes and combinations thereof. Any listed scope can be readily identified as sufficiently describing and enabling the same scope to be decomposed into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each scope discussed herein can be readily decomposed into a lower third, a middle third, and an upper third, etc. As those skilled in the art will also understand, all language, such as “up to,” “at least,” “greater than,” “less than,” and the like, including the stated numbers, refers to a scope that can subsequently be decomposed into subscopes as described above. Finally, as those skilled in the art will understand, a scope includes each individual member. Thus, for example, a group having 1-3 units means a group having 1, 2, or 3 units. Similarly, a group having 1-5 units means a group having 1, 2, 3, 4, or 5 units, and so on.

[0509] Furthermore, the claims should not be construed as limited to the provided order or elements unless otherwise stated. Additionally, the use of the term "means for..." in any claim is intended to invoke 35 USC § 112. 6. The format of a claim consisting of a device plus a function, and any claim without the term "device for..." is not intended to be so.

Claims

1. A wireless transmit / receive unit (WTRU), comprising: The processor, memory, and transceiver are configured as follows: Receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2), wherein the configuration information includes any one of the following: (i) the minimum number of beams and / or cells to be used in determining the LTM quality, (ii) offset and / or scaling information, (iii) the association between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using LTM quality as serving cell quality or as an offset of serving cell quality. Receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with trigger conditions. Perform first measurements on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell. The first LTM quality is determined using a first measurement and configuration information associated with determining the LTM quality, and Reports associated with L1 / L3 measurement events are sent based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. These reports include information indicating the quality of the first LTM.

2. The WTRU according to claim 1, wherein, The processor, memory, and transceiver are configured as follows: Perform a second measurement on one or more beams of the target cell and one or more beams of other cells associated with the target cell, and The second measurement is used to determine the quality of the second LTM.

3. The WTRU according to claim 2, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

4. The WTRU according to claim 2, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on a comparison of (i) the serving cell quality using a first LTM quality offset and / or scaling with (ii) the second LTM quality.

5. The WTRU according to claim 4, wherein, The quality of the serving cell is determined using a first measurement of one or more beams of the serving cell.

6. The WTRU according to claim 1, wherein, The processor, memory, and transceiver are configured as follows: Perform a second measurement on one or more beams of the target cell, and The second measurement is used to determine the quality of the target cell.

7. The WTRU according to claim 6, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the target cell quality.

8. The WTRU according to claim 6, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on (i) a comparison between the quality of the serving cell using a first LTM quality offset and / or scaling and (ii) the quality of the target cell.

9. The WTRU according to claim 4, wherein, The quality of the serving cell is determined using a first measurement of one or more beams of the serving cell.

10. The WTRU according to any one of claims 1-9, wherein, The report is sent to one of the other cells associated with one or more beams of the serving cell, or to any one of the serving cells.

11. The WTRU according to any one of claims 2-10, wherein, The processor, memory, and transceiver are configured to perform LTM cell handover to the target cell based on the fulfillment of triggering conditions, and The report was sent to the target cell.

12. The WTRU according to any one of claims 2-10, wherein, The processor, memory, and transceiver are configured to perform conditional reconfiguration based on the fulfillment of trigger conditions, and The report was sent to the target cell.

13. A wireless transmit / receive unit (WTRU), comprising: The processor, memory, and transceiver are configured as follows: Receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2), wherein the configuration information includes any one of the following: (i) the minimum number of beams and / or cells to be used in determining the LTM quality, (ii) offset and / or scaling information, (iii) the association between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using the LTM quality as the target cell quality or as an offset of the target cell quality. Receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with trigger conditions. Perform first measurements on one or more beams of the target cell and one or more beams of other cells associated with the target cell. The first LTM quality is determined using a first measurement and configuration information associated with determining the LTM quality, and Reports associated with L1 / L3 measurement events are sent based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. These reports include information indicating the quality of the first LTM.

14. The WTRU of claim 13, wherein, The processor, memory, and transceiver are configured as follows: Perform a second measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell, and The second measurement is used to determine the quality of the second LTM.

15. The WTRU according to claim 14, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on a comparison of (i) the first LTM quality and (ii) the second LTM quality.

16. The WTRU of claim 14, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on (i) a comparison of the target cell quality using a first LTM quality offset and / or scaling with (ii) the second LTM quality.

17. The WTRU according to claim 16, wherein, The quality of the target cell is determined using a first measurement of one or more beams of the target cell.

18. The WTRU of claim 14, wherein, The processor, memory, and transceiver are configured as follows: Perform a second measurement on one or more beams of the serving cell, and A second measurement is used to determine the quality of the serving cell.

19. The WTRU according to claim 14, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on a comparison of (i) the quality of the first LTM and (ii) the quality of the serving cell.

20. The WTRU of claim 14, wherein, The processor, memory, and transceiver are configured to determine whether the triggering condition is met based on (i) a comparison between the target cell quality using a first LTM quality offset and / or scaling and (ii) the serving cell quality.

21. The WTRU according to any one of claims 14-20, wherein, The report is sent to one of the other cells associated with one or more beams of the serving cell, or to any one of the serving cells.

22. The WTRU according to any one of claims 14-20, wherein, The processor, memory, and transceiver are configured to perform LTM cell handover to the target cell based on the fulfillment of triggering conditions, and The report is then sent to the target cell.

23. A method implemented by a wireless transmit / receive unit (WTRU), the method comprising: Receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2), wherein the configuration information includes any one of the following: (i) the minimum number of beams and / or cells to be used in determining the LTM quality, (ii) offset and / or scaling information, (iii) the association between one or more beams of the serving cell and one or more beams of other cells, and / or (iv) an indication of using LTM quality as serving cell quality or as an offset of serving cell quality; Receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions; Perform a first measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell; The first LTM quality is determined using a first measurement and configuration information associated with determining the LTM quality; as well as Reports associated with L1 / L3 measurement events are sent based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. These reports include information indicating the quality of the first LTM.

24. The method of claim 23, further comprising: Perform a second measurement on one or more beams of the target cell and one or more beams of other cells associated with the target cell; as well as The quality of the second LTM is determined using a second measurement.

25. The method of claim 24, further comprising determining the satisfaction of the triggering condition based on a comparison of (i) the quality of the first LTM and (ii) the quality of the second LTM.

26. The method of claim 24, further comprising determining whether the triggering condition is met based on a comparison of (i) the serving cell quality using a first LTM quality offset and / or scaling with (ii) the second LTM quality.

27. The method according to claim 26, wherein, The quality of the serving cell is determined using a first measurement of one or more beams of the serving cell.

28. The method of claim 23, further comprising: Perform a second measurement on one or more beams of the target cell; as well as The second measurement is used to determine the quality of the target cell.

29. The method of claim 28 further comprises determining the satisfaction of the triggering condition based on a comparison of (i) the first LTM quality and (ii) the target cell quality.

30. The method of claim 28 further comprises determining whether the triggering condition is met based on a comparison of (i) the quality of the serving cell using a first LTM quality offset and / or scaling with (ii) the quality of the target cell.

31. The method according to claim 26, wherein, The quality of the serving cell is determined using a first measurement of one or more beams of the serving cell.

32. The method according to any one of claims 23-31, wherein, The report is sent to one of the other cells associated with one or more beams of the serving cell, or to any one of the serving cells.

33. The method according to any one of claims 24-32, further comprising performing an LTM cell handover to the target cell based on satisfying a triggering condition, and The report is then sent to the target cell.

34. The method according to any one of claims 24-32, further comprising performing conditional reconfiguration based on satisfying a triggering condition, and The report is then sent to the target cell.

35. A method implemented by a wireless transmit / receive unit (WTRU), the method comprising: Receive configuration information associated with determining the mobility (LTM) quality triggered by Layer 1 or Layer 2 (L1 / L2), wherein the configuration information includes any one of the following: (i) the minimum number of beams and / or cells to be used in determining the LTM quality, (ii) offset and / or scaling information, (iii) the association between one or more beams of the target cell and one or more beams of other cells, and / or (iv) an indication of using LTM quality as the target cell quality or as an offset of the target cell quality; Receive configuration information indicating L1 or L3 (L1 / L3) measurement events associated with triggering conditions; Perform first measurements on one or more beams of the target cell and one or more beams of other cells associated with the target cell; The first LTM quality is determined using a first measurement and configuration information associated with determining the LTM quality; as well as Reports associated with L1 / L3 measurement events are sent based on the fulfillment of triggering conditions and the minimum time period that has elapsed since the last LTM cell handover. These reports include information indicating the quality of the first LTM.

36. The method of claim 35, further comprising: Perform a second measurement on one or more beams of the serving cell and one or more beams of other cells associated with the serving cell; as well as The quality of the second LTM is determined using a second measurement.

37. The method of claim 36 further comprises determining the satisfaction of the triggering condition based on a comparison of (i) the quality of the first LTM and (ii) the quality of the second LTM.

38. The method of claim 36 further comprises determining whether the triggering condition is met based on a comparison of (i) the target cell quality using a first LTM quality offset and / or scaling with (ii) the second LTM quality.

39. The method according to claim 38, wherein, The quality of the target cell is determined using a first measurement of one or more beams of the target cell.

40. The method of claim 36, further comprising: Perform a second measurement on one or more beams of the serving cell; as well as A second measurement is used to determine the quality of the serving cell.

41. The method of claim 36, further comprising: The triggering condition is determined by comparing (i) the quality of the first LTM and (ii) the quality of the serving cell.

42. The method of claim 36 further comprises determining whether the triggering condition is met based on a comparison of (i) the target cell quality using a first LTM quality offset and / or scaling with (ii) the serving cell quality.

43. The method according to any one of claims 36-42, wherein, The report is sent to one of the other cells associated with one or more beams of the serving cell, or to any one of the serving cells.

44. The method according to any one of claims 36-42, further comprising performing an LTM cell handover to the target cell based on satisfying a triggering condition, and The report is then sent to the target cell.

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