Systems and methods for reference signal measurements in wireless systems

Abstract

To provide systems, apparatuses, and methods for receiving downlink control information (DCI) that may include an indication of a reference measurement resource (RMR), receiving an indication of a measurement configuration, and receiving an indication of a feedback resource configuration.SOLUTION: A measurement report based on an indication of an RMR, an indication of a measurement configuration, and an indication of a feedback resource configuration may be generated and may be transmitted to a network device.SELECTED DRAWING: Figure 6

Description

Technical Field

[0001] The present invention relates to wireless communication.

Background Art

[0002] Cross - reference to Related Applications This application claims priority to U.S. Provisional Patent Application No. 62 / 315,405, filed Mar. 30, 2016; U.S. Provisional Patent Application No. 62 / 334,788, filed May 11, 2016; and U.S. Provisional Patent Application No. 62 / 416,397, filed Nov. 2, 2016, each of which is entitled "Systems and Methods for Reference Signal Measurements in Wireless Systems" and is hereby incorporated by reference in its entirety.

[0003] Cell - specific reference signals (CRS) can be used in a wireless system for channel estimation to perform coherent demodulation of physical channels, for collecting channel state information (CSI) for a transmission mode (TM), and / or for higher - layer measurements used in cell selection and handover decisions. It may be desirable to reduce the reference signal overhead to limit unwanted interference to neighboring transmit / receive points (TRP) and / or to reduce power consumption at the TRP.

Summary of the Invention

[0004] The summary of the present invention is provided to introduce a selected example of the disclosed, non - limiting concepts in a simplified form that will be further described below in the mode for carrying out the invention. The summary of the present invention is not intended to identify the main features and / or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter.

[0005] A system, apparatus, and method are disclosed for receiving downlink control information (DCI) that may include an indication of a reference measurement resource (RMR), receiving an indication of a measurement configuration, and receiving an indication of a feedback resource configuration. A measurement report based on the indication of the RMR, the indication of the measurement configuration, and / or the indication of the feedback resource configuration may be generated and transmitted to a network device.

[0006] An indication of an association of the RMR with at least one of a measurement configuration or a feedback resource configuration may be received. The DCI may include information that may be associated with one or more of mobility relation measurements, channel state information (CSI) measurements, demodulation processes, positioning, radio link monitoring, or cell collection. The DCI may also, or instead, include an indication of a change in the active state of the RMR. The DCI may also, or instead, include information for scheduling transmissions.

[0007] The measurement configuration may include criteria that may be associated with a filtered selection of RMR instances and / or RMR resources. The measurement configuration may also, or instead, include an indication of an RMR process and / or an RMR instance. The measurement configuration may also, or instead, include an indication of a measurement type and / or an indication of a measurement purpose. The measurement configuration may also, or instead, include an indication of a trigger criterion. The measurement report may be transmitted to the network device based on, or in response to, a determination based on the indication of the trigger criterion.

Brief Description of the Drawings

[0008] The following detailed description of various non-limiting examples is made with reference to the accompanying drawings. The drawings are provided to assist in the description of various non-limiting examples for the purpose of the description. The intended subject matter is not limited to the specific elements and / or means described or illustrated. Instead, without specific notation, the subject matter described herein is not intended as necessary and / or essential. The examples described may be employed in whole or in part, in any combination.

Figure 1A

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[0009] A detailed description of non-limiting examples will be made with reference to various figures. This description gives detailed examples of the possible examples, but it should be noted that the details are intended to be illustrative and in no way limit the scope of the application examples. Without further modification or characterization, the articles "a" or "an" used in this specification can be understood to mean, for example, "one or more" or "at least one". Also, the phrase "user equipment" (UE) used in this specification can be understood to also refer to a "wireless transmit / receive unit" (WTRU).

[0010] Figure 1A is a diagram of an exemplary communication system 100 in which one or more of the disclosed examples may be implemented. The communication system 100 can be a multi-connection system that can provide content such as voice, data, video, messaging, broadcast, etc. to a plurality of wireless users. The communication system 100 can enable a plurality of wireless users to access such content through sharing of system resources, including but not limited to wireless bandwidth. For example, the communication system 100 can 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), etc.

[0011] As shown in Figure 1A, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, and / or 102d (which may generally or collectively be referred to herein as WTRU 102), radio access networks (RANs) 103 / 104 / 105, core networks 106 / 107 / 109, public switched telephone network (PSTN) 108, Internet 110, and / or other networks 112. The disclosed examples 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. For example, each of the WTRUs 102a, 102b, 102c, 102d may be configured to transmit and / or receive wireless signals and may be a user equipment (UE), mobile station, fixed subscriber unit, mobile subscriber unit, pager, cellular phone, personal digital assistant (PDA), smartphone, laptop, netbook, personal computer, wireless sensor, consumer electronics, etc., or any combination thereof.

[0012] The communication system 100 may also include base station 114a and 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 the WTRUs 102a, 102b, 102c, and 102d to facilitate access to one or more communication networks such as core networks 106 / 107 / 109, Internet 110, and / or other networks 112. For example, each of base stations 114a and 114b may be a base transceiver station (BTS), Node B, eNode B, home Node B, home eNode B, site controller, access point (AP), wireless router, etc., or any combination thereof. Although base stations 114a and 114b are each shown as a single element, it is contemplated that each of base stations 114a and 114b may include any number of interconnected base stations and / or network elements.

[0013] Base station 114a may also be part of RAN 103 / 104 / 105 and may include any number of other base stations and / or network elements (not shown), such as a base station controller (BSC), a radio network controller (RNC), a relay node, etc. Base station 114a and / or base station 114b may be configured to transmit and / or receive radio signals within a geographic area, sometimes referred to as a cell. A cell may be divided into cell sectors. For example, the cell associated with base station 114a may be divided into three cell sectors. In the example, base station 114a may include, for example, three transceivers and may include one transceiver for each sector of the cell associated with base station 114a. In another example, base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell associated with base station 114a.

[0014] Base stations 114a and 114b may each communicate with one or more of WTRUs 102a, 102b, 102c, and 102d via air interfaces 115 / 116 / 117, which may be any suitable radio communication link (e.g., radio frequency (RF), microwave, infrared (IR), ultraviolet (UV), visible light, etc.). Air interfaces 115 / 116 / 117 may be established using any suitable radio access technology (RAT).

[0015] The communication system 100 can be a multi-connection system and can adopt one or more channel access methods such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, each of the base stations 114a in RAN103 / 104 / 105 and WTRU102a, 102b, and 102c can establish air interfaces 115 / 116 / 117 using wideband CDMA (WCDMA (registered trademark)) and can implement radio technologies such as Universal Mobile Telecommunications System (UMTS) terrestrial radio access (UTRA). WCDMA can include the use of 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).

[0016] In another example, the base station 114a and WTRU102a, 102b, and 102c can establish air interfaces 115 / 116 / 117 using Long-Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and can implement radio technologies such as evolved UMTS terrestrial radio access (E-UTRA).

[0017] In other examples, the base station 114a and WTRU102a, 102b, and 102c can implement radio technologies such as IEEE 802.16 (i.e., WiMAX (Worldwide Interoperability for Microwave Access)), CDMA2000, CDMA2000 IX, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM (registered trademark)), GSM Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0018] The base station 114b in FIG. 1A 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 an office, a home, a vehicle, a campus, etc. In the example, the base station 114b as well as the WTRUs 102c and 102d can implement a wireless technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In another example, the base station 114b as well as the WTRUs 102c and 102d can implement a wireless technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another example, the base station 114b as well as the WTRUs 102c and 102d can utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, etc.) to establish a picocell or a femtocell. As shown in FIG. 1A, the base station 114b can have a direct connection to the Internet 110. The base station 114b may not be required to access the Internet 110 via the core network 106 / 107 / 109.

[0019] RAN 103 / 104 / 105 may communicate with core networks 106 / 107 / 109. Core networks 106 / 107 / 109 can be any type of network configured to provide voice, data, applications, and / or VoIP (Voice over Internet Protocol) services to one or more of WTRUs 102a, 102b, 102c, and 102d. For example, core networks 106 / 107 / 109 can provide call control, billing services, mobile location information services, prepaid originating calls, Internet connectivity, video delivery, etc., and / or implement high-level security functions such as user authentication. RAN 103 / 104 / 105 and / or core networks 106 / 107 / 109 may communicate directly and / or indirectly with other RANs that may employ the same RAT and / or a different RAT as RAN 103 / 104 / 105. For example, in addition to being connected to RAN 103 / 104 / 105 which may utilize E-UTRA radio technology, core networks 106 / 107 / 109 may also communicate with another RAN that employs GSM radio technology.

[0020] The core network 106 / 107 / 109 can also act as a gateway for one or more of the WTRUs 102a, 102b, 102c, and 102d that can be used to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 can include a circuit-switched telephone network that can provide plain old telephone service (POTS). The Internet 110 can include a global system of interconnected computer networks and devices that use common communication protocols such as TCP, UDP, and / or IP in the TCP / IP Internet protocol suite. The other networks 112 can include wired and / or wireless communication networks that are owned and / or operated by other service providers. For example, the other networks 112 can include a core network connected to one or more RANs, each of which can employ the same RAT and / or a different RAT as the RANs 103 / 104 / 105.

[0021] Some or all of the WTRUs 102a, 102b, 102c, and 102d in the communication system 100 can include multimode capabilities. For example, each of the WTRUs 102a, 102b, 102c, and 102d can include multiple transceivers for communicating with different wireless networks via different wireless links. For example, the WTRU 102c shown in Figure 1A can be configured to communicate with a base station 114a that can employ cellular-based wireless technology and with a base station 114b that can employ IEEE 802 wireless technology.

[0022] Figure 1B is a system diagram of an exemplary WTRU 102 that may represent a WTRU such as any of WTRUs 102a, 102b, 102c, and 102d. As shown in Figure 1B, the WTRU 102 may include any of a processor 118, a transceiver 120, a transmit / receive element 122, a speaker / microphone 124, a keypad 126, a display / touchpad 128, a non-removable memory 130, a removable memory 132, a power supply 134, a GPS chipset 136, and other peripheral devices 138. The WTRU 102 may include any sub-combination of the above elements while remaining consistent with the disclosed examples. Each of base stations 114a and 114b, and / or, without limitation, any node that base stations 114a and 114b may represent, such as a base transceiver station (BTS), a Node B, a site controller, an access point (AP), a home Node B, an evolved home Node B (eNode B), a home evolved Node B (HeNB), a home evolved Node B gateway, and a proxy node, is contemplated to be able to include any or all of the elements shown in Figure 1B and described herein.

[0023] The processor 118 may be a general-purpose processor, a dedicated processor, a conventional processor, a digital signal processor (DSP), a plurality of microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, one or more ASICs, one or more FPGA circuits, other types of integrated circuits (ICs), a state machine, etc., or any combination thereof. The processor 118 may perform signal encoding, data processing, power control, input / output processing, and / or any other functionality that enables the WTRU 102 to operate in a wireless environment. The processor 118 may be coupled to the transceiver 120, which may be coupled to the transmit / receive element 122. Although Figure 1B shows the processor 118 and the transceiver 120 as separate components, it is contemplated that the processor 118 and the transceiver 120 may be incorporated into each other in an electronic package or chip.

[0024] The transceiver element 122 may be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via the air interfaces 115 / 116 / 117. For example, in an example, the transceiver element 122 may be an antenna configured to transmit and / or receive RF signals. In another example, the transceiver element 122 may be an emitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In another example, the transceiver element 122 may be configured to transmit and / or receive both RF signals and optical signals. The transceiver element 122 may be configured to transmit and / or receive any combination of wireless signals.

[0025] The transceiver element 122 shown in FIG. 1B may be a single element, but the WTRU 102 may include any number of transceiver elements 122. The WTRU 102 may employ MIMO technology. In an example, the WTRU 102 may include two or more transceiver elements 122 (e.g., multiple antennas) for transmitting and / or receiving wireless signals via the air interfaces 115 / 116 / 117.

[0026] The transceiver 120 may be configured to modulate signals that may be transmitted by the transceiver element 122 and / or demodulate signals that may be received by the transceiver element 122. The WTRU 102 may have multi-mode capabilities. The transceiver 120 may include multiple transceivers that may enable the WTRU 102 to communicate via multiple RATs, such as, for example, UTRA and / or IEEE 802.11.

[0027] The processor 118 of the WTRU 102 may be coupled to and / or receive user input data from a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (which may be, for example, a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 may also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. The processor 118 may access information from and / or store data in any suitable type of memory, such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 may include RAM, ROM, a hard disk, and / or other types of memory storage devices. The removable memory 132 may include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, etc., or any combination thereof. The processor 118 may access information from and / or store data in a memory that is not physically located in the WTRU 102, such as a memory located in a server or a home computer.

[0028] The processor 118 may receive power from a power supply 134 and may be configured to supply and / or control power to other components of 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 cells (such as nickel cadmium (NiCd), nickel zinc (NiZn), nickel metal hydride (NiMH), lithium ion (Li ion), etc.), a solar cell, a fuel cell, etc., or any combination thereof.

[0029] The processor 118 may also be coupled to a GPS chipset 136 that may be configured to provide location information (e.g., longitude and latitude) regarding the current location of the WTRU 102. In addition to, or instead of, the location information provided by the GPS chipset 136, the WTRU 102 may receive location information from a base station (e.g., base stations 114a, 114b) via the air interface 115 / 116 / 117, and / or may determine its location based on the timing of signals received from two or more nearby base stations. It will be appreciated that the WTRU 102 may collect location information by any suitable location determination method while remaining consistent with the disclosed examples.

[0030] The processor 118 may further be coupled to a peripheral device 138 that may include one or more software and / or hardware modules that may provide additional features, functionality and / or connectivity (wired and / or wireless). For example, the peripheral device 138 may include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (capable of capturing photos and / or video), a USB port, a vibration device, a television transceiver, a hands-free headset, a Bluetooth® module, a frequency modulation (FM) radio unit, a digital music player, a media player, a video game player module, an Internet browser, etc., or any combination thereof.

[0031] Figure 1C is a system diagram of an example RAN 103 and core network 106. RAN 103 may employ UTRA radio technology to communicate with WTRUs 102a, 102b, and / or 102c via air interface 115. RAN 103 may also communicate with core network 106. RAN 103 may include Node Bs 140a, 140b, and / or 140c, each of which may include one or more transceivers for communicating with WTRUs 102a, 102b, and / or 102c via air interface 115. Node Bs 140a, 140b, and 140c may each be associated with a cell within RAN 103. RAN 103 may include one or both of RNCs 142a and 142b, and / or any other RNC. RAN 103 may include any number of Node Bs and RNCs while remaining consistent with the intended example.

[0032] Node Bs 140a and 140b may communicate with RNC 142a. Node B 140c may communicate with RNC 142b. Node Bs 140a and 140b may communicate with RNC 142a via the Iub interface. Node B 140c may communicate with RNC 142b via the Iub interface. RNC 142a and RNC 142b may communicate with each other via the Iur interface. Each of RNCs 142a and 142b may be configured to control their respective connected Node Bs 140a, 140b, and 140c. Each of RNCs 142a and 142b may also or alternatively be configured to perform and / or support other functionality such as, for example, outer loop power control, load control, admission control, packet scheduling, handover control, macro diversity, security functions, data encryption, etc., or any combination thereof.

[0033] The core network 106 of FIG. 1C may include a media gateway (MGW) 144, a mobile switching center (MSC) 146, a serving GPRS support node (SGSN) 148, and / or a gateway GPRS support node (GGSN) 150. Each of the above elements is shown as part of the core network 106, but one or more of these elements may be owned and / or operated by an entity other than the operator of the core network 106.

[0034] The RNC 142a in the RAN 103 may be connected to the MSC 146 in the core network 106 via the IuCS interface. The MSC 146 may be connected to the MGW 144. The MSC 146 and the MGW 144 may provide access to a circuit-switched network, such as the PSTN 108, to the WTRUs 102a, 102b, and / or 102c to facilitate communication between the WTRUs 102a, 102b, and / or 102c and legacy fixed-line communication devices.

[0035] The RNC 142a in the RAN 103 may be connected to the SGSN 148 in the core network 106 via the IuPS interface. The SGSN 148 may be connected to the GGSN 150. The SGSN 148 and / or the GGSN 150 may provide access to a packet-switched network, such as the Internet 110, to the WTRUs 102a, 102b, and / or 102c to facilitate communication between the WTRUs 102a, 102b, and / or 102c and IP-enabled devices.

[0036] As described above, the core network 106 may also be connected to other networks 112 that may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0037] Figure 1D is a system diagram of RAN 104 and core network 107 by way of example. RAN 104 may employ E-UTRA radio technology to communicate with WTRUs 102a, 102b, and / or 102c via air interface 116. RAN 104 may also or alternatively be in communication with core network 107.

[0038] RAN 104 may include eNodeBs 160a, 160b, and / or 160c, although it is contemplated that RAN 104 may include any number of eNodeBs while remaining consistent with the disclosed example. eNodeBs 160a, 160b, and 160c may each include one or more transceivers for communicating with WTRUs 102a, 102b, and / or 102c via air interface 116. In an example, one or more of eNodeBs 160a, 160b, and 160c may implement MIMO technology. eNodeB 160a, for example, may use multiple antennas to transmit and / or receive radio signals from WTRU 102a.

[0039] Each of eNodeBs 160a, 160b, and 160c may be associated with a cell and / or may be configured to handle radio resource management decisions, handover decisions, scheduling of users during uplink and / or downlink, or any combination thereof. eNodeBs 160a, 160b, and / or 160c may each communicate with one another via the X2 interface.

[0040] Core network 107 of Figure 1D may include mobility management gateway (MME) 162, serving gateway 164, and / or packet data network (PDN) gateway 166. Each of these elements may be part of core network 107, although it is contemplated that any one or more of these elements may be owned and / or operated by an entity other than the core network operator.

[0041] The MME 162 can be connected to one or more of the eNodeBs 160a, 160b, and 160c in the RAN 104 via the S1 interface and / or can act as a control node. For example, the MME 162 can be responsible for authenticating one or more of the users of the WTRUs 102a, 102b, and 102c, bearer activation / deactivation, selecting a serving gateway during the initial attach of the WTRUs 102a, 102b, and / or 102c, etc., or any combination thereof. The MME 162 can provide control plane functions for switching between the RAN 104 and other RANs that may employ other radio technologies such as GSM or WCDMA.

[0042] The serving gateway 164 can be connected to one or more of the eNodeBs 160a, 160b, and 160c in the RAN 104 via the S1 interface. The serving gateway 164 can route and / or forward user data packets to and / or from the WTRUs 102a, 102b, and / or 102c. The serving gateway 164 can also or alternatively perform other functions such as anchoring the user plane during eNodeB handover, triggering paging when downlink data is available for the WTRUs 102a, 102b, and / or 102c, managing and / or storing the context of the WTRUs 102a, 102b, and / or 102c, etc., or any combination thereof.

[0043] The serving gateway 164 can be connected to a PDN gateway 166 that can provide the WTRUs 102a, 102b, and / or 102c with access to a packet switched network such as the Internet 110 to facilitate communication between the WTRUs 102a, 102b, and / or 102c and IP-enabled devices.

[0044] The core network 107 may facilitate communication with other networks. For example, the core network 107 may provide access to a circuit-switched network, such as the PSTN 108, to the WTRUs 102a, 102b, and / or 102c to facilitate communication between the WTRUs 102a, 102b, and / or 102c and legacy landline communication devices. The core network 107 may include, and / or communicate with, an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that may act as an interface between the core network 107 and the PSTN 108. The core network 107 may provide the WTRUs 102a, 102b, and / or 102c with access to other networks 112, which may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0045] Figure 1E is a system diagram of an example RAN 105 and core network 109. The RAN 105 may be an Access Service Network (ASN) that may employ IEEE 802.16 wireless technology to communicate with one or more of the WTRUs 102a, 102b, and 102c via an air interface 117. Communication links between the different functional entities of the WTRUs 102a, 102b, and 102c, the RAN 105, and the core network 109 may be defined as reference points.

[0046] RAN 105 may include base stations 180a, 180b, and / or 180c, and / or ASN gateway 182, although it is contemplated that RAN 105 may include any number of base stations and / or ASN gateways while remaining consistent with the disclosed examples. Base stations 180a, 180b, and 180c may each be associated with a cell in RAN 105 and / or may each include one or more transceivers for communicating with WTRUs 102a, 102b, and / or 102c via air interface 117. In an example, base stations 180a, 180b, and / or 180c may implement MIMO technology. Base station 180a, for example, may use multiple antennas to transmit and / or receive radio signals from WTRU 102a. Base stations 180a, 180b, and / or 180c may also provide mobility management functions such as handoff triggering, tunnel establishment, radio resource management, traffic classification, quality of service (QoS) policy enforcement, etc., or any combination thereof. ASN gateway 182 may act as a traffic aggregation point and / or may be responsible for paging, caching of subscriber profiles, routing to core network 109, etc., or any combination thereof.

[0047] Air interface 117 between WTRUs 102a, 102b, and / or 102c and RAN 105 may be defined as an R1 reference point that may implement the IEEE 802.16 specification. One or more of WTRUs 102a, 102b, and / or 102c may establish a logical interface with core network 109. The logical interface between WTRUs 102a, 102b, and / or 102c and core network 109 may be defined as an R2 reference point (not shown) that may be used for authentication, authorization, IP host configuration management, and / or mobility management, or any combination thereof.

[0048] A communication link between any of base stations 180a, 180b, and 180c may be defined as an R8 reference point that may include a protocol for facilitating WTRU handover between base stations and / or transfer of data. A communication link between base stations 180a, 180b, and / or 180c and ASN gateway 182 may be defined as an R6 reference point. The R6 reference point may include a protocol for facilitating mobility management based on mobility events associated with one or more of WTRU102a, 102b, and 102c.

[0049] RAN105 may be connected to core network 109. A communication link between RAN105 and core network 109 may be defined as an R3 reference point that may include one or more protocols for facilitating, for example, data transfer and / or mobility management capabilities. Core network 109 may include one or more of mobile IP home agent (MIP-HA) 184, authentication, authorization, accounting (AAA) server 186, and gateway 188. Each of such elements is shown as part of core network 109 in FIG. 1E, but it is contemplated that any one or more of these elements may be owned and / or operated by an entity other than the core network operator.

[0050] The MIP-HA 184 may be responsible for IP address management and may enable the WTRU 102a, 102b, and / or 102c to roam between different ASNs and / or different core networks. The MIP-HA 184 may provide the WTRU 102a, 102b, and / or 102c with access to a packet switched network, such as the Internet 110, to facilitate communication between the WTRU 102a, 102b, and / or 102c and IP-enabled devices. The AAA server 186 may be responsible for supporting user authentication and / or user services. The gateway 188 may facilitate interaction with other networks. For example, the gateway 188 may provide the WTRU 102a, 102b, and / or 102c with access to a circuit switched network, such as the PSTN 108, to facilitate communication between the WTRU 102a, 102b, and / or 102c and legacy landline communication devices. The gateway 188 may provide the WTRU 102a, 102b, and / or 102c with access to other networks 112, which may include other wired and / or wireless networks that may be owned and / or operated by other service providers.

[0051] It is contemplated that the RAN 105 may be connected to other ASNs and / or that the core network 109 may be connected to other core networks. A communication link between the RAN 105 and one or more other ASNs may be defined as an R4 reference point that may include a protocol for coordinating the mobility of the WTRU 102a, 102b, and / or 102c between the RAN 105 and such other ASNs. A communication link between the core network 109 and one or more other core networks may be defined as an R5 reference point that may include a protocol for facilitating interaction between one or more home core networks and one or more visited core networks.

[0052] In the LTE example, multiple downlink reference signals (RSs) can be transmitted for one or more purposes. A WTRU can receive a cell-specific reference signal (CRS) from a PCell and / or an SCell. Such a CRS can be transmitted in a downlink subframe in a frequency division duplexing (FDD) example. Alternatively, or in addition, such a CRS can be transmitted in a downlink subframe and / or a downlink pilot time slot (DwPTS) in a time division duplexing (TDD) example. One or more CRSs can also, or instead, be transmitted in one or more resource blocks in the frequency domain.

[0053] In LTE, eight resource elements (REs) per antenna port per physical resource block (PRB) can be used for the transmission of one or more CRSs. Note that in other examples, fewer or more REs per antenna port per PRB can be used for the transmission of one or more CRSs.

[0054] The CRS can assist one or more WTRUs in performing channel estimation for the coherent demodulation of one or more downlink physical channels. In an example, one or more WTRUs may not use the CRS for the demodulation of some downlink channels such as the physical multicast channel (PMCH), the physical downlink shared channel (PDSCH), and / or the enhanced physical downlink control channel (EPDCCH). The CRS can be used to collect channel state information (CSI) for one or more transmission modes (TMs), e.g., transmission modes 1 to 8. The CRS can be used for higher layer measurements such as for the basis for cell selection and / or for the basis for handover determination.

[0055] The WTRU-specific reference signal associated with the PDSCH may be referred to as a Demodulation Reference Signal (DM-RS). The DM-RS can be transmitted using one or more of the same resources that can be used for the associated PDSCH and can be used for coherent demodulation of such PDSCH (e.g., for transmission modes 7 to 10) and / or to enable channel estimation for demodulation of one or more other PDSCHs. The DM-RS can be associated with the PDSCH based on one or more of any type of configuration, indication, and / or rule (e.g., not based on the use of one or more of the same resources) and can be used with the PDSCH specified in such configuration, indication, and / or rule.

[0056] The DM-RS can also, or instead, be used to enable demodulation of the EPDCCH channel. The DM-RS can be transmitted on one or more antenna ports, each of which can be associated with some of the layers used for transmission of the PDSCH and / or EPDCCH. The DM-RS can be transmitted on one or more physical resource blocks. In an example, one or more DM-RS can be transmitted on one or more physical resource blocks on which the corresponding PDSCH and / or EPDCCH can be mapped. In an example, one or more DM-RS can be mapped to a number of REs per PRB, such as 12 REs per PRB. Alternatively, or in addition, one or more DM-RS can use Orthogonal Cover Codes (OCC) to enable up to a number of ports, such as 8 ports, and can be transmitted on a number of REs per PRB, such as 24 REs per PRB.

[0057] A CSI reference signal (CSI-RS) resource can be used to enable one or more WTRUs in one or more TMs, such as a WTRU in TM9-10, to collect CSI. The CSI-RS resource can have a lower time and / or frequency density than the CRS. For example, the periodicity of the CSI-RS resource can be, for example, 80 subframes, where two resource elements per antenna port per physical resource block can be used for the CSI-RS resource.

[0058] A WTRU in a TM, such as a WTRU in TM10, can be configured with channel state information interference measurement (CSI-IM). The CSI-IM configuration can indicate to the WTRU resources where the WTRU can expect zero-power transmissions from the serving cell. Such CSI-IM resources can be used by the WTRU to make measurements, for example, based on the assumption that the measured signal can be interference plus noise.

[0059] The WTRU can be configured to make CSI measurements for the CRS and / or CSI-RS depending on the transmission mode (TM) in some examples. Such measurements can include one or more of a rank indicator (RI), a channel quality indicator (CQI), a precoder matrix indicator (PMI), and a precoding type indicator (PTI). The WTRU can report such CSI measurements either in one or more physical uplink control channel (PUCCH) resources (e.g., for periodic CSI reporting) and / or in one or more physical uplink shared channel (PUSCH) resources (e.g., for UCI on the PUSCH or for aperiodic CSI reporting).

[0060] Either or both of the periodic CSI report and the aperiodic CSI report can be configured using one or more of a plurality of reporting modes. Such modes can indicate whether wideband CQI feedback reports can be used, whether WTRU selected sub-band CQI feedback reports can be used, and / or (e.g., in the case of an aperiodic report) whether higher layer configured sub-band CQI feedback reports can be used. The reporting mode can indicate whether PMI feedback reports may not be used, whether a single PMI feedback report can be used, or (e.g., in the case of an aperiodic report) whether multiple PMI feedback reports can be used.

[0061] For CQI calculation, the WTRU may determine the interference level. The way in which the WTRU determines the interference level may depend on the implementation. For example, the WTRU may determine the interference level as the noise on the cell-specific reference signal. The WTRU may average the interference levels over a plurality of subframes. CSI-IM may be used as a resource that the WTRU may use to measure the interference level.

[0062] The WTRU may be configured with a plurality of CSI processes, for example, to support multi-point cooperation (CoMP). The CSI process may include a combination of CSI-RS and CSI-IM. In some examples, the WTRU may be configured to report separate CSI for each CSI process, periodically and / or aperiodically.

[0063] A WTRU may be configured to perform cell selection and / or enable handover. Such a WTRU may be configured in radio resource control (RRC) using measurement reports of measurements such as, for example, reference signal received power (RSRP), reference signal strength indicator (RSSI), and / or reference signal received quality (RSRQ). The WTRU may report such measurements in an RRC measurement report. The WTRU may be configured to continuously measure, for example, multiple cells. Based on whether the conditions under which the measurements can be configured are met, the WTRU may be triggered to report such measurements.

[0064] In an example, new radio (NR) access may be used in a fifth instantiation of mobile communication such as, for example, 5G. NR may be used herein to refer to the 5G radio access protocol. The various use cases contemplated for NR may contribute to determining the capabilities and / or requirements for a system implementing NR access. The contemplated approach for the design of a system such as a 5G system may at least partially correspond to NR access technologies that can meet 5G requirements without limiting the applicability of the disclosed examples to such a system.

[0065] The air interface may enable one or more of improved broadband performance (e.g., IBB), industrial control and communication (e.g., ICC), vehicle use cases (e.g., V2X), and massive machine type communication (e.g., mMTC). For example, NR may be designed to handle and / or multiplex IBB, ICC, V2X, and / or mMTC communications.

[0066] Support may be provided for baseband filtering of frequency domain waveforms. Baseband filtering of frequency domain waveforms may enable aggregation of at least 150 - 200 MHz of the total spectrum within the RF transceiver path.

[0067] Spectrum aggregation across relatively widely separated operating bands (e.g., 900 MHz, 3.5 GHz) may use multiple RF transceiver chains in some examples due to antenna size requirements and / or amplifier optimization design constraints. For example, a WTRU implementation may include three separate RF transceiver paths such as a first path below, for example, 1 GHz, a second path for the 1.8 - 3.5 GHz frequency range, and a third path for the 4 - 6 GHz frequency range.

[0068] Native built - in support for large - scale MIMO antenna configurations may be a secondary requirement.

[0069] IBB examples may use multiple frequency bands, each having a spectrum of varying size. Such bands may be aggregated to achieve data rates on the order of, for example, from 10 Mbps to several Gbps (e.g., up to 8 Gbps) at (e.g., cell edge) peak data rates with typical rates on the order of, for example, several 100 Mbps.

[0070] Ultra - low transmission latency can be supported by, for example, an air interface latency as low as about 1 ms round - trip time (RTT) by supporting one or more transmission time intervals (TTIs) between, for example, 100 μs and 250 μs. Support for ultra - low access latency (e.g., the time from initial system access to completion of transmission of the first user plane data unit) can also, or alternatively, be supported by implementations that, for example, use ICC and / or V2X and / or specify an end - to - end (e2e) latency of less than, for example, 10 ms.

[0071] Ultra-reliable transmission can be supported by providing a transmission reliability that is lower than that which can be found, for example, in legacy LTE systems. Support for mobility with speeds in the range of 0 to 500 km / h can be achieved in an example. For example, implementations using ICC and / or V2X can specify a packet loss rate of less than 10e -6 Support for machine type communication (MTC) operations (such as narrowband operation, etc.) can be provided. The air interface can support narrowband operation (using, for example, less than 200 KHz), extended battery life (for example, up to 15 years of autonomy), and / or minimum communication overhead for small and / or rare data transmissions (for example, low data rates in the range of 1 to 100 kbps with access latencies from seconds to hours). Support for large-scale MTC (mMTC) examples can be provided by narrowband operation implementations. The associated link budget can be comparable to the link budget for LTE extended coverage, but a very large number (for example, up to 200 k / km2) of MTC devices can be supported.

[0072] (For example, narrowband operation, etc.) Support for machine type communication (MTC) operations can be provided. The air interface can support narrowband operation (using, for example, less than 200 KHz), extended battery life (for example, up to 15 years of autonomy), and / or minimum communication overhead for small and / or rare data transmissions (for example, low data rates in the range of 1 to 100 kbps with access latencies from seconds to hours). Support for large-scale MTC (mMTC) examples can be provided by narrowband operation implementations. The associated link budget can be comparable to the link budget for LTE extended coverage, but a very large number (for example, up to 200 k / km2) of MTC devices can be supported.

[0073] The system design can enable flexible spectrum utilization, deployment strategies, and / or operations. One or more operations can use a spectrum of varying sizes and / or it can include the aggregation of non-adjacent carriers in the same and / or different frequency bands (for example, licensed and / or unlicensed frequency bands). Support for narrowband and / or wideband operations, different multiplexing methods (for example, in a TDD example, dynamically variable downlink (DL) / uplink (UL) allocation), variable TTI lengths, scheduled and / or unscheduled transmissions, synchronous and / or asynchronous transmissions, separation of the user plane from the control plane, and / or multi-node connectivity can be provided.

[0074] The system can be integrated with one or more legacy Universal Terrestrial Radio Access Networks (UTRANs), Evolved Universal Terrestrial Radio Access Networks (EUTRANs), Evolved Packet Cores (EPCs) / Core Networks (CNs), and / or associated aspects. The system can be integrated with and / or operate using one or more legacy interfaces and / or associated evolved interfaces. The system communicates with a legacy CN (e.g., by using an S1 interface, non-access stratum, etc.) and / or may communicate with one or more legacy eNodeBs (e.g., by using an X2 interface that may include dual connectivity with an LTE entity). Such an exemplary system can enable legacy aspects, such as support for existing QoS and / or security mechanisms.

[0075] Elements of the disclosed examples can be included in LTE evolution examples, for example, to provide backward compatibility for some or all of the components. For example, a TTI shorter than an LTE slot (e.g., 0.5 ms) can use a waveform different from the waveforms used in an LTE evolved system to enable ultra-low latency. For example, the physical layer (DL and / or UL) can be operated, for example, in TDM and / or in FDM using LTE. The functionality that can be supported by a legacy system can be provided by enabling device-to-device (D2D) functionality and / or sidelink functionality, license-assisted access (LAA) operation using listen-before-talk (LBT), and / or support for relays.

[0076] OFDM can be used as a basic signal format for data transmission in LTE and / or IEEE802.11. OFDM can divide the spectrum into a plurality of parallel orthogonal sub-bands. Each sub-carrier can be shaped using a rectangular window in the time domain, which can lead to a synchronized shaped sub-carrier in the frequency domain. OFDMA examples can have perfect frequency synchronization and tight management of uplink timing alignment within the duration of the cyclic prefix, for example, to maintain orthogonality between signals and / or to minimize inter-carrier interference. Such synchronization may not be used in a system where a WTRU can be connected to multiple access points simultaneously. For example, power reduction can be applied to uplink transmission to comply with spectrum emission requirements of adjacent bands in the presence of aggregation of fragmented spectrum for transmission by the WTRU.

[0077] Aspects of conventional OFDM (e.g., cyclic prefix (CP) OFDM (CP-OFDM)) can be addressed by more stringent RF requirements. Such examples can be used when operating using a large amount of continuous spectrum that may not require aggregation. The CP-based OFDM transmission scheme can lead to a downlink physical layer similar to that of a legacy system's downlink physical layer when modifications to pilot signal density and location are implemented.

[0078] Other waveform candidates can be used, but conventional OFDM can be considered a candidate for downlink transmission schemes.

[0079] The downlink transmission scheme can be based on a multi-carrier waveform that can be characterized by high spectral suppression (e.g., lower side lobes and / or lower out-of-band (OOB) emissions). The multi-carrier (MC) waveform candidates can include orthogonal frequency division multiplexing / offset quadrature amplitude modulation (OFDM / OQAM) and universal filter multi-carrier (UFMC) (e.g., universal filter OFDM (UF-OFDM)). The multi-carrier modulation waveform can divide the channel into one or more sub-channels and modulate data symbols on sub-carriers in such sub-channels.

[0080] In the OFDM-OQAM example, a filter can be applied to the OFDM signal in the time domain for each sub-carrier to reduce OOB emissions. The use of OFDM-OQAM in the example can result in very low interference for adjacent bands, may not use a large guard band, and may not use a cyclic prefix. The OFDM-OQAM example can be sensitive to the multi-path effect and / or high delay spread with respect to orthogonality, which can complicate equalization and / or channel estimation.

[0081] In the UFMC (UF-OFDM) example, a filter can be applied to the OFDM signal in the time domain to reduce OOB emissions. The filtering process can be applied for each sub-band to use spectral fragments. The OOB emissions in the (one or more) unused spectral fragments in the band can remain as high as the OOB emissions in conventional OFDM. For example, UF-OFDM can improve across OFDM at the edges of the filtered spectrum but may not improve in spectral holes.

[0082] Multiplexing can be implemented at the frequencies of signals having non-orthogonal characteristics (such as different sub-carrier intervals). Further, or alternatively, coexistence of asynchronous signals can be used. Such examples may not require a complex interference cancellation receiver. Aggregation of spectrum fragments in baseband processing can be an alternative to a system that aggregates spectrum fragments as part of RF processing.

[0083] Coexistence of different waveforms within the same band can be used, for example, to support mMTC narrowband operation (such as using single carrier multiple access (SCMA)). The same band can support combinations of different waveforms, such as CP-OFDM, OFDM-OQAM, and / or UF-OFDM, for any or all of the disclosed aspects, and / or for one or both of downlink and uplink transmissions. Such waveform coexistence can be used, for example, with transmissions that can use different types of waveforms between different WTRUs, either simultaneously, with some overlap, and / or consecutively in the time domain, and / or with transmissions that can use different types of waveforms than the same WTRU.

[0084] Waveforms and / or transmissions that can support at least one cyclical prefix (CP) duration that varies depending on the case (e.g., from one transmission to another), combinations of CP and low power tails (e.g., 0 tails), forms of hybrid guard intervals (e.g., using low power CPs and adaptive low power tails), and any combinations thereof, etc., can support hybrid types of waveforms. Such hybrid types of waveforms can support further aspects of dynamic variation and / or control, such as the application of filtering processes. For example, a hybrid type of waveform can assist in determining whether the filtering process can be applied for each sub - band and / or for each group thereof at the edges of the spectrum used for the reception of (one or more) transmissions for a given carrier frequency, at the edges of the spectrum used for the reception of transmissions associated with a specific spectrum operation mode (SOM). The uplink transmission scheme can use the same or different waveforms as those used for downlink transmissions. Multiplexing of transmissions to and / or from various WTRUs in the same cell can be based on FDMA and / or TDMA.

[0085] Spectrum flexibility can enable deployment in different frequency bands with different characteristics, including different duplex configurations of the available spectrum that can include contiguous and / or non - contiguous spectrum allocations in the same and / or different bands, and / or different and / or variable sizes, and can support variable timing aspects. Support for multiple TTI lengths and / or support for asynchronous transmissions can be provided.

[0086] TDD and / or FDD duplexing modes may be supported. In FDD operation, supplementary downlink operation may be supported using spectrum aggregation. FDD operation may support either or both full-duplex FDD operation and half-duplex FDD operation. For TDD operation, the DL / UL allocation may be dynamic. For example, the DL / UL allocation may not be based on a fixed DL / UL frame configuration. The length of the DL and / or UL transmission intervals may be set for each transmission opportunity.

[0087] The transmission bandwidths on the uplink and downlink may be different from each other. For example, the bandwidth of each of the uplink and downlink may independently range from the nominal system bandwidth to the maximum value corresponding to the system bandwidth.

[0088] In single-carrier operation, the system bandwidth may include 5, 10, 20, 40, and / or 80 MHz. The system bandwidth may be any bandwidth within a given range, e.g., from a few MHz to 160 MHz (or more). The nominal bandwidth may have one or more fixed values. Narrowband transmissions up to a specified frequency such as 200 KHz may be supported within the operating bandwidth for MTC devices.

[0089] Figure 2 shows an exemplary transmit bandwidth 200. As used herein, "system bandwidth" may refer to the largest portion of the spectrum that can be managed by the network for a given carrier, such as the system bandwidth 210 in Figure 2. For such a carrier, the portion that a WTRU can minimally support for cell acquisition, measurement, and / or initial access to the network may correspond to the nominal system bandwidth, such as the nominal system bandwidth 220 in Figure 2. A WTRU may be composed of channel bandwidths that can be within the entire range of the system bandwidth. For example, WTRUx as shown in Figure 2 may be composed of a channel bandwidth 230 that can be a 10 MHz bandwidth including the nominal system bandwidth 220. In another example, WTRUy as shown in Figure 2 may be composed of a channel bandwidth 240 that can be all of the system bandwidth 210 including the nominal system bandwidth 220. Some or all of the channel bandwidths utilized by the WTRU may support NR access.

[0090] Each of channel bandwidths 230 and 240 includes the nominal system bandwidth 220, but the configured channel bandwidth of the WTRU may or may not include the nominal portion of the system bandwidth as shown in the exemplary transmit bandwidth 200 of Figure 2. For example, bandwidths 230 and 240 include the nominal system bandwidth 220, but WTRUz as shown in Figure 2 may be composed of a channel bandwidth 250 that may not include the nominal system bandwidth 220.

[0091] One or more sets of RF requirements for the maximum operating bandwidth in a band can be met without the introduction of additional allowed channel bandwidth for that operating band, which may enable bandwidth flexibility. Baseband filtering of frequency domain waveforms may be supported. The physical layer may be band agnostic and / or may support operation in an authorized band below, for example, 5 GHz and / or operation in an unlicensed band in the range of, for example, 5 - 6 GHz. An LBT CAT4 based channel access framework, which may be similar to LTE LAA, may be supported, for example, in operation in an unlicensed band.

[0092] Downlink control channels and / or signals may support FDM operation. The WTRU may collect downlink carriers, for example, by receiving transmissions using a nominal portion of the system bandwidth, where the WTRU may not initially receive transmissions covering the entire bandwidth that can be managed by the network for the associated carrier.

[0093] The downlink data channel may be allocated on a bandwidth that may or may not correspond to the nominal system bandwidth. For example, the bandwidth on which the downlink data channel may be allocated may be determined without limitation other than being within the configured channel bandwidth of the WTRU. In an exemplary, non - limiting example, the network may operate a carrier with a 12 MHz system bandwidth using a 5 MHz nominal bandwidth that enables a device supporting a maximum RF bandwidth of at most 5 MHz to collect and / or access the system while allocating +10 to - 10 MHz of the carrier frequency to other WTRUs that may support a channel bandwidth equivalent of up to 20 MHz.

[0094] Figure 3 shows a chart 300 illustrating an exemplary spectrum allocation that includes a system bandwidth 310 and a nominal system bandwidth 315. Different subcarriers can be assigned to different operating modes. Such operating modes may be referred to as "spectrum operating modes" or "SOMs". Figure 3 shows exemplary subcarriers 320 and 330. Subcarrier 320 can be assigned to a SOM different from the SOM associated with subcarrier 330.

[0095] Different SOMs can be used to meet different requirements for different transmissions. A SOM can include, and / or be characterized by, and / or be defined by, and / or be associated with one or more of a subcarrier spacing, a symbol length, a TTI length, and a reliability aspect (such as a hybrid automatic repeat request (HARQ) processing mode). A SOM can also, or instead, include, and / or be characterized by, and / or be defined by, and / or be associated with one or more of a specific secondary control channel, a specific waveform, any physical layer aspect. For example, an LTE signal can correspond to a first SOM. A first type of NR transmission can correspond to a second SOM. In an example, NR can support transmissions from multiple SOMs, such as a first SOM for NR supporting a large-scale broadband type use case, a second SOM for NR supporting an ultra-reliable low-latency communication (URLLC) type use case, a third SOM for NR supporting an mMTC type use case, etc. A SOM can be used to refer to a specific waveform and can also be related to processing aspects, such as aspects that support the coexistence of different waveforms in the same carrier using FDM and / or TDM. Similarly, a SOM can be used, for example, in a TDM-like manner or a similar implementation form, when the coexistence of FDD operations in a TDD band can be supported. As shown in Figure 3, portions of the carrier / spectrum can be associated with variable transmission characteristics to support transmissions associated with different SOMs at various times.

[0096] In single-carrier operation, spectrum aggregation may be supported. The WTRU may support the transmission and / or reception of multiple transport blocks on a set of contiguous and / or non-contiguous physical resource blocks (PRBs) within the same operating band. A single transport block may be mapped to a separate set of PRBs. Simultaneous transmissions associated with different SOM requirements may be supported.

[0097] Multi-carrier operation may be supported. Contiguous and / or non-contiguous spectrum blocks may be used within the same operating band and / or across two or more operating bands. Spectrum blocks using different modes (e.g., FDD and TDD) and / or different channel access methods (e.g., licensed and unlicensed band operation) may be aggregated. The multi-carrier aggregation of the WTRU may be configured, reconfigured, and / or dynamically changed. In some examples, efficient baseband filter processing in the frequency domain may obviate the use of RF specification work to support additional channels and / or band combinations.

[0098] Downlink and uplink transmissions may be framed into radio frames characterized by one or more fixed aspects (e.g., location of downlink control information) and one or more varying aspects (e.g., transmission timing, type of transmission supported). A basic time interval (BTI) may be expressed in terms of an integer number of one or more symbols. The symbol duration may be a function of the sub-carrier spacing applicable to the time-frequency resource. In an FDD system, the sub-carrier spacing may differ between the uplink carrier frequency f UL and the downlink carrier frequency f DL and may vary.

[0099] A transmission time interval (TTI) may be the minimum time between successive transmissions supported by the system. Each successive transmission is a downlink (TTIDL ) and can be associated with different transport blocks (TBs) for the downlink transceiver (DL TRx) and the uplink transceiver (UL TRx), and can exclude the preamble. Each successive transmission can include control information (e.g., downlink control information (DCI) for the downlink, uplink control information (UCI) for the uplink). The TTI can be represented with respect to an integer number of one or more BTI. The BTI is unique and / or can be associated with the SOM. The frame duration can include, but is not limited to, 100 μs, 125 μs (1 / 8 ms), 142.85 μs (e.g., 1 / 7 ms can be two nCP LTE OFDM symbols), and / or 1 ms. One or more frame durations can be selected to enable alignment with the legacy LTE timing structure.

[0100] A frame has an associated carrier frequency, e.g., f for TDD UL+DL and f for FDD DL and can be preceded by a fixed duration t for downlink data transmission (DL TRx) for dci and can start with DCI that can have.

[0101] Frame structure 400 of FIG. 4 shows an exemplary frame structure that can be used in a TDD duplex example. The TDD duplex example can use a frame that can consist of both a downlink portion (DCI and DL TRx) and an uplink portion (UL TRx), such as frame 410 that can include DCI411, DL TRx412, and UL TRx413. Also, frame 420 that can include DCI421, DL TRx422, and UL TRx423 is shown in FIG. 4. The TDD duplex example can also or instead use a frame that can consist of a downlink portion (DCI and DL TRx) rather than an uplink portion (UL TRx). A switching gap (swg), such as swg414 and swg424, can precede the uplink portion of the frame for a given configuration of the frame, for example.

[0102] TDD examples can support D2D, V2X, and / or sidelink operations in a frame by including respective downlink control and / or forward transmissions in the DCI+DL TRx portion of such a frame (e.g., when semi-static allocation of each resource is used), or in the DL TRx portion of such a frame (e.g., in the case of dynamic allocation). Each reverse transmission can be included in the UL TRx portion.

[0103] The frame structure 500 of FIG. 5 shows an exemplary frame structure that can be used in an FDD duplex example and can use a frame that may include one or more TTIs for a downlink reference TTI and / or an uplink. An FDD duplex example can use a frame that can consist of both a downlink portion (DCI and DL TRx) and an uplink portion (UL TRx), such as frame 510 that may include DCI 511, DL TRx 512, and UL TRx 513. Also, frame 520 that may include DCI 521, DL TRx 522, and UL TRx 523 is shown in FIG. 5. The uplink portion, such as uplink portion 514 that overlaps frames 510 and 520, can overlap two frames.

[0104] The start of the uplink TTI is derived using an offset (e.g., t offset 530) as shown in FIG. 5. The offset can be applied from the start of the downlink reference frame that may overlap the start of the uplink frame. offset ) which can be derived using an offset (e.g., t

[0105] FDD examples can support D2D, V2X, and / or sidelink operations in the UL TRx portion of a frame by including respective downlink control, forward, and / or reverse transmissions in the UL TRx portion of such a frame (e.g., when dynamic allocation of one or more respective resources can be used).

[0106] The scheduling function may be supported at the Medium Access Control (MAC) layer. Two or more scheduling modes may be supported. The scheduling mode may be network-based scheduling that may be used for tight scheduling regarding downlink transmission and / or uplink transmission resources, timing, and transmission parameters. Another scheduling mode may be WTRU-based scheduling that may provide flexibility regarding timing and / or transmission parameters. For any or both of such modes, scheduling information may be valid for a single TTI or for multiple TTIs.

[0107] Network-based scheduling may be used, for example, to enable the network to manage available radio resources that may be allocated to various WTRUs. Such a scheduling scheme may be used to improve sharing of such resources. Dynamic scheduling may also or alternatively be supported.

[0108] WTRU-based scheduling may be used to assist the WTRU in opportunistically accessing uplink resources with minimal latency, as needed, within a set of shared and / or dedicated uplink resources that may be (dynamically or otherwise) allocated by the network. Synchronous and asynchronous opportunistic transmissions are contemplated in the present disclosure. Contention-based transmission and contention-free transmission are contemplated in the present disclosure.

[0109] Support for opportunistic transmission (scheduled or unscheduled) may be used to address ultra-low latency requirements associated with some configurations and / or power saving requirements associated with some configurations.

[0110] The association of data available for transmission and resources available for uplink transmission can be supported. Multiplexing of data with different QoS requirements within the same transport block can be supported, for example, where such multiplexing may not have an adverse impact on services with stringent QoS requirements and / or may not result in unnecessary waste of system resources.

[0111] Transmission can be encoded using one or more encoding methods. Different encoding methods can have different characteristics. For example, an encoding method can generate a sequence of information units, which may sometimes be called "blocks". Each information unit can be independent such that an error in the transmission of the first block does not impair the receiver's ability to successfully decode the second block. For example, if the first block has an error, the second block can be error-free and / or have sufficient redundancy so that the second block can be successfully decoded by the receiver, and the first block may not be decoded due to the error associated with the first block.

[0112] Encoding methods such as Raptor / Fountain codes can be used where the transmission can consist of a sequence of N Raptor codes. One or more such codes can be mapped in time to one or more transmission "symbols". Such symbols can correspond to one or more sets of information bits (e.g., one or more octets). Such encoding can be used to add forward error correction (FEC) to the transmission so that the transmission can be more resilient to the loss of one "symbol", for example, by interference from another overlapping transmission in time or by puncturing, such that the transmission can use N + 1 or N + 2 Raptor codes (or symbols assuming Raptor code symbol relationships).

[0113] A WTRU may be configured to receive and / or detect one or more system signatures. The system signature may include a signal structure that may use sequences. A signal including such a system signature may be similar to a synchronization signal (e.g., similar to an LTE primary synchronization signal (PSS) or secondary synchronization signal (SSS)). The system signature may be unique to a particular node and / or transmit / receive point (TRP) within a given area (e.g., uniquely identify). Alternatively, or in addition, the system signature may be common to multiple nodes and / or TRPs within the area. Whether the signature is unique to a node and / or TRP may be unknown and / or irrelevant information to the WTRU. A network TRP that supports NR transmission and / or reception may sometimes be referred to as a gNB.

[0114] A WTRU may determine and / or detect a system signature sequence and may determine one or more parameters associated with the system. For example, the WTRU may derive an index from the system signature sequence and may use this index to look up associated parameters, e.g., by using a table such as an access table as described herein. If the WTRU determines that it may access and / or transmit using the applicable resources of the system, the WTRU may use the received power associated with the system signature for open loop power control, e.g., to set an initial transmit power. If the WTRU determines that it may access and / or transmit using the applicable resources of the system, the WTRU may use the timing of the received signature sequence, e.g., to set the timing of a transmission (e.g., a preamble on a PRACH resource).

[0115] The WTRU may be configured with a list having one or more entries. Such a list may be referred to as an access table. The access table may be indexed such that each entry may be associated with a system signature and / or a sequence associated with the system signature. The access table may provide initial access parameters for one or more areas. Each access table entry may provide one or more parameters that may be used to effect an initial access to the system. The parameters included in the access table may include, for example, one or more physical random access channel (PRACH) resources in time and / or frequency, other applicable physical layer resources, an initial power level, one or more physical layer resources that may be used for reception of a response, etc., in any combination, including a set of random access parameters.

[0116] The parameters associated with an access table entry may also or instead include access restrictions, such as public land mobile network (PLMN) identification information and / or CSG information. Such parameters may also or instead include routing related information, such as one or more applicable routing areas. Each table entry may be associated with and / or indexed by a system signature. One entry may be common to multiple nodes and / or TRPs.

[0117] The WTRU may receive or obtain the access table by transmissions using dedicated resources, such as resources associated with an RRC configuration, and / or transmissions using broadcast resources. When broadcast resources may be used, the periodicity of the transmission of the access table may be relatively long (e.g., up to 10240 ms) such that it may be longer than the periodicity of the transmission of the signature (e.g., within the range of 100 ms).

[0118] Reduction of transmission, and thereby reduction of bandwidth usage, may be desirable. Reduction of signals in a system may reduce unwanted interference for an adjacent transmit receive point (TRP), reduce reference signal overhead, and / or reduce power consumption at the transmit point.

[0119] Reduction of reference signal overhead may be beneficial for mobile broadband communication, for example, in an environment where support for two or more transmission methods (e.g., massive MIMO, CoMP) may be provided. Reducing reference signal overhead (e.g., pilot contamination) and / or reducing interference between TRPs may increase coverage of higher order modulation transmissions and may be beneficial for a WTRU operating in such an environment. Reduction of interference between TRPs may be beneficial for ultra-reliable communication.

[0120] A WTRU may perform measurements on one or more reference signals and may use such measurements for one or more of various purposes such as to measure received power, to measure channel quality, to enable derivation of CSI, to enable channel estimation for demodulation, etc. The WTRU may need to know when to expect transmission of a reference signal. Various methods and systems that may be used to indicate the presence of one or more reference signals to a WTRU are described.

[0121] Reduction of signal transmission may be achieved by reducing the periodicity of some such signals. In some operating modes (e.g., ultra-reliable communication), it may be undesirable to introduce a lag between measured CSI feedback and actual transmission, such as may be experienced with reduction of the periodicity of some signals.

[0122] To limit transmission of one or more reference signals, a WTRU may perform multiple operations on one or more (e.g., one) reference signal types. The WTRU may be informed of the purpose of the reference signal.

[0123] Note that the acronym "NR" for a new radio may be used herein to identify a new radio interface that may be different from the LTE interface. NR may also be used to indicate an interface intended for use in future systems. The systems and methods described herein may be applicable to either or both of the reception of one or more reference measurement resources (RMRs) and the transmission of one or more RMRs.

[0124] A WTRU may be composed of one or more RMRs. In the downlink, one or more RMRs may be used to perform measurements on at least one signal transmission (e.g., if present, a transmitted signal RMR may be used to perform measurements on at least one signal), and / or to perform measurements on resources where at least one signal may not be expected (e.g., if present, a blanked RMR may be used to perform measurements on one or more resources where at least one signal may not be expected).

[0125] In the uplink, one or more RMRs may be used to perform at least one signal transmission (e.g., if present, a transmitted signal RMR may be used to perform at least one signal transmission). Alternatively, or in addition, transmission may not be performed (e.g., based on a blanked RMR if present). Note that the examples described herein referring to the reception of RMRs by a WTRU (e.g., DL RMR or SL RMR) may also be applicable to the transmission of RMRs by a WTRU (e.g., UL RMR or SL RMR).

[0126] The WTRU may detect the presence of one or more resources on which the WTRU may perform one or more measurements. Such a resource may be an RMR. The RMR may be a non-zero power reference signal on which at least one TRP may transmit a signal. The RMR may also be, or instead, a zero power reference signal on which at least one TRP may not transmit a signal (e.g., one or more TRPs may not transmit a signal on an unused resource). The non-zero power reference signal RMR may be referred to as a "transmitted signal RMR". The zero power reference signal RMR may be referred to as a "blanked RMR".

[0127] As used herein, "transmission of an RMR" may refer to either or both of a transmitted signal RMR and a blanked RMR. Further, "transmission of an RMR" as used herein should be understood as equivalent to the "presence of an RMR" (e.g., in a resource grid that may represent a set of applicable physical layer resources).

[0128] The transmitted RMR may be an RMR that may be transmitted by the WTRU in UL, while the blanked RMR may be a set of resources on which the WTRU may not transmit anything. For example, the blanked RMR may indicate to the WTRU a pattern of resources on which the WTRU may rate match and / or puncture UL transmissions.

[0129] It should be noted that the examples described herein may be described in the context of reference measurement resources that may be transmitted by one or more TRPs, and the disclosed examples are also contemplated to be applicable to a WTRU that may transmit one or more RMRs, for example, when operating in a device-to-device communication mode.

[0130] The RMR can be characterized by one or more parameters. One or more RMRs can be configured for a WTRU. Such a WTRU may expect that at least one TRP can transmit a signal. Such a WTRU may use specific parameters that enable the WTRU to use advanced detection to perform the required measurements. For example, the RMR can be defined (and / or configured thereby) by at least one of various parameters.

[0131] Parameters associated with the RMR can include, but are not limited to, resource element mapping. The resource element mapping can map the RMR to a set of resource elements in one or more symbols and / or to one or more subcarriers. In an example, the RMR can be a concatenation of a plurality of resource elements.

[0132] Parameters associated with the RMR can include, but are not limited to, in some examples, a sequence that can be pre-determined. For example, a signal transmitted on the RMR by at least one TRP can be a pre-determined sequence. The sequence can be generated, for example, using a pseudo-random sequence. The sequence can be generated using one or more other parameters of the RMR.

[0133] Parameters associated with the RMR can include, but are not limited to, a unique word, such as unique word OFDM (UW-OFDM), that can be used to transmit the RMR. The guard period can be used in one or more frame structures (e.g., in a stand-alone subframe where the DL and UL portions can be separated by the guard period). Such a guard period can be used to transmit the RMR.

[0134] Parameters associated with RMR may include, but are not limited to, signal structure. RMR may have a signal structure different from that of one or more parallel transmissions. For example, RMR may use a first subcarrier spacing, and one or more parallel non-RMR transmissions may use a second subcarrier spacing. RMR may also, or instead, assume a first TTI duration or subframe duration, and one or more parallel non-RMR transmissions may use a second TTI duration or subframe duration.

[0135] Parameters associated with RMR may include, but are not limited to, transmission power. The transmission power of RMR may be fixed or may vary across different realizations of the same RMR. The RMR transmission power may be associated with parallel transmissions on another channel.

[0136] Parameters associated with RMR may include, but are not limited to, analog beams. Multiple RMRs may be multiplexed in the same or overlapping resources using different beams.

[0137] Parameters associated with RMR may include, but are not limited to, precoding. The precoding used to transmit RMR on multiple antenna ports may be fixed or may be variable. The RMR precoding may be associated with parallel transmissions on another channel.

[0138] Parameters associated with RMR may include, but are not limited to, a set of antenna ports. The set of antenna ports may be used for transmission from one or more TRPs.

[0139] Parameters associated with RMR may include, but are not limited to, cover codes. Multiple RMRs may be multiplexed in the same or overlapping resources using orthogonal cover codes.

[0140] Parameters associated with RMR may include, but are not limited to, timing aspects. RMR may be associated with time periodically with respect to symbols within a subframe, with respect to a subframe (e.g., one or more symbols), and / or with respect to a radio frame (e.g., multiple subframes).

[0141] Note that any of the parameters associated with RMR described herein may be associated with one or more of downlink transmission, uplink transmission, and / or sidelink transmission.

[0142] RMR configured for a WTRU for which it can be expected that one or more TRPs are not transmitting may use the same and / or similar parameters as those described herein for RMR configured for a WTRU for which it can be expected that one or more TRPs are transmitting a signal.

[0143] One or more blanked RMRs may be assumed by the WTRU to consist of interference and noise. In such an example, the WTRU may perform energy detection.

[0144] One or more blanked RMRs may be used by the WTRU to measure a particular type of interference. The WTRU may be configured by the NR network node with blanked RMRs to enable the WTRU to measure interference from other RATs (e.g., LTE, Wi-Fi, etc.). Such a WTRU may be configured with parameters associated with inter-RAT interference. The targeted interference measurement may be kept separate from one or more measurements performed by the WTRU for energy detection.

[0145] One or more blanked RMRs may be used by a WTRU to measure one or more signals transmitted by one or more other RATs. The WTRU may be composed of at least one blanked RMR that may coincide with the transmission of LTE CSI-RS (or other types of LTE RS) from an LTE cell that may be collocated with a TRP (e.g., an NR TRP) with which the WTRU communicates. The WTRU may also, or instead, be composed of blanked RMRs that may coincide with the transmission of LTE CSI-RS from an LTE cell that is not collocated with the TRP with which the WTRU communicates. The WTRU may be composed of at least one blanked RMR that may enable inter-RAT mobility measurements.

[0146] The WTRU may be configured to perform one or more measurements. Such measurements may be performed on one or more RMRs. Each of such one or more measurements may be associated with a purpose corresponding to a particular procedure.

[0147] The measurements may be associated with one or more WTRU procedures including, but not limited to, procedures for cell, signature, TRP, TRP group (TRPG), and sidelink WTRU selection. The measurements may also, or instead, be associated with one or more other WTRU procedures including, but not limited to, mobility-related measurements (e.g., cell / signature / TRPG or intra- or inter-RAT), radio link monitoring (RLM)-related logic, radio link failure (RLF)-related logic, demodulation processes, etc.

[0148] The purpose for the measurements may correspond to SOM. For example, the measurements may be associated with the operation of a particular service, transport channel (TrCH), and / or physical channel (or type thereof).

[0149] Measurements can be used locally, e.g., by a WTRU, and / or to provide feedback that can be reported by the WTRU to at least one TRP. The WTRU can be configured dynamically or semi-statically to perform specific measurements on one or more RMRs. The WTRU can autonomously determine the measurements to be taken on one or more RMRs.

[0150] Any one or more of the measurements can be performed for any one or more of several purposes. The measurements can be used to identify a TRP. If one or more RMRs are used by the WTRU to determine the presence of one or more TRPs, measurements of such one or more RMRs can be used to identify one or more TRPs. The RMR can implicitly or explicitly indicate a TRP identifier (e.g., via a parameter). As used herein, a TRP can refer to a node and / or a transmission configuration. Exemplary transmission configurations can include the specific beam used by the TRP.

[0151] Measurements can be used to identify another WTRU. An RMR can be used by a first WTRU to determine the presence of a second WTRU or a set of other WTRUs. Alternatively, or in addition, an RMR can be used by a first WTRU to identify a second WTRU or a set of other WTRUs. The second WTRU can be configured to transmit into an RMR configured for the first WTRU. The second WTRU can transmit a signal that explicitly or implicitly provides identification information to the first WTRU.

[0152] Measurements can be used for synchronization. The WTRU can use an RMR to synchronize with one or more TRPs and / or with another one or more WTRUs. The RMR can be used for coarse and / or fine time synchronization. Additionally, or alternatively, the RMR can be used for coarse and / or fine frequency synchronization.

[0153] Measurements can be used to perform one or more mobility measurements, also sometimes called upper layer measurements. Mobility measurements can include one or more of RMR received power (e.g., power measured on one or more RMRs), RMR received quality (e.g., power measured on one or more RMRs divided by a signal strength indicator), and RMR signal strength indication (e.g., power measured on one or more symbols).

[0154] Measurements can be used to determine path loss estimates (or similar measurements) for one or more TRPs and / or another one or more WTRUs. Such measurements can be used in combination with one or more other parameters. The RMR can have a fixed transmit power or a configurable transmit power, either of which can be known or indicated to the WTRU. The WTRU can use the received power of the RMR in combination with the transmit power of the RMR to determine path loss.

[0155] Measurements can be used to perform CSI measurements. The WTRU can use the RMR to obtain CSI measurements that can include, but are not limited to, one or more of rank, preferred precoder matrix, channel quality, selected subbands, interference, primary interferer identification, preferred beam, preferred channel, signal-to-interference plus noise ratio (SINR), channel outage, WTRU speed, coherence time, and coherence bandwidth.

[0156] Measurements can be used to perform Radio Link Monitoring (RLM). A WTRU may use RMR to perform RLM. A WTRU may determine whether the received signal strength can exceed a threshold. The threshold may be associated with the required Control Channel Block Error Rate (BLER) performance. Such a threshold may be configurable. The threshold may depend on the transmission and / or reception parameters of the WTRU. For example, different traffic types (e.g., eMBB, Ultra-Reliable and Low Latency Communications (“URLLC”), mMTC) may have different associated thresholds.

[0157] Measurements can be used to perform demodulation. A WTRU may use RMR to perform channel estimation that may be used in demodulation.

[0158] Measurements can be used to perform Quasi-Co-Location (QCL). A WTRU may use RMR to obtain fine frequency and / or timing estimates. QCL measurements may include one or more of Doppler shift, Doppler spread, mean delay, and delay spread. The QCL information obtained on a first RMR may be used with a second or other RMR.

[0159] Measurements can be used to perform Clear Channel Assessment. A WTRU may use RMR to perform one or more measurements that may be used to determine, for example, a Clear Channel Assessment for an unlicensed channel.

[0160] Measurements can be used to perform signal structure identification. A WTRU may use RMR to determine a preferred signal structure. Alternatively, or in addition, a WTRU may use RMR to blindly determine the signal structure that may be in use. A WTRU may perform measurements assuming different signal structures and may use a correlation receiver to determine the signal structure in use.

[0161] Measurements can be used to determine channel occupancy. The WTRU may use RMR to determine the number of devices that may be using a channel. For example, the WTRU may use RMR to detect signal messages from other devices (e.g., other WTRUs) to determine channel occupancy. Alternatively, or in addition, the WTRU may use RMR to measure the utilization of a set of resources (e.g., a portion of the resources used by other devices to transmit data). The utilization of the set of resources may be determined based on energy detection and / or control channel detection. The WTRU may be configured with different measurement thresholds that may be associated with different channel occupancy values. Channel occupancy may also, or alternatively, be determined according to how often the measurement exceeds or falls below the measurement threshold during a set of measurement occasions.

[0162] Measurements can be used to determine the type of channel utilization based on RMR measurements, the presence of RMR, and / or RMR parameters. The WTRU may have limited access to a channel (e.g., a shared access channel) depending on the current channel utilization type. The channel utilization type may be a SOM, a transmission type (e.g., URLLC or mMTC), or a user's shared spectrum tier (e.g., incumbent, priority access license (PAL) tier, general authorized access (GAA) tier). The WTRU may be configured with blanked RMR. Such a WTRU may determine, for example, the type of interference present within one or more resources of such blanked RMR to determine the type of channel utilization. In an example, such a WTRU may also perform one or more other determinations based on such a determination of the type of interference.

[0163] Measurements can be used to perform speed and / or Doppler estimation. The WTRU may use one or more RMRs to estimate the speed of the WTRU. The WTRU may also, or alternatively, use one or more RMRs to feedback measurements to the network for speed estimation purposes. Such measurements may be based on the relative timing of reception of one or more associated signals.

[0164] Measurements can be used to determine positioning. The WTRU may use one or more RMRs to determine the location of the WTRU. The WTRU may also, or alternatively, use one or more RMRs to feedback measurements to the network for positioning purposes. One or more associated signals may be designed to enable positioning.

[0165] Any measurement purpose and measurement type, and any combination thereof, may be implemented in accordance with the present disclosure. Any measurement purpose and measurement type, and any combination thereof, may be a configuration aspect according to the present disclosure. All such measurement purposes and measurement types, and any combination thereof, are contemplated as being within the scope of the present disclosure.

[0166] The WTRU may determine one or more RMR configurations "blindly". Such determination may be based on signals and / or RMR transmissions and / or transmission parameters, either or both of which may not be associated with the RMR for which the WTRU is determining the configuration. The WTRU may determine one or more RMR configurations based on signal structure, SOM, and / or frame structure. The waveform in use may indicate one or more RMR configurations.

[0167] A WTRU may determine one or more RMR configurations in response to a downlink signal that may not be associated with one or more RMRs for which the WTRU may be attempting to determine a configuration. The WTRU may determine one or more RMR configurations in response to one or more access parameters. For example, the WTRU may determine an RMR configuration using TRP identification information, TRPG identification information, a system signature, cell identification information, and / or physical resources that may be applicable for preamble transmission. The WTRU may determine one or more RMR configuration aspects in response to preamble transmission (e.g., a selected preamble, PRACH resources, applicable subframe) and / or in response to a radio network temporary identifier (RNTI) for decoding a response, such as a random access RNTI (RA-RNTI).

[0168] A WTRU may be configured for transmission and / or reception of one or more RMRs. Such a configuration may be dynamic, semi-static, or static. The RMR configuration may be indicated via the physical layer and / or one or more upper layers. If the WTRU may be semi-statically configured with one or more RMR configurations, one or more of such configurations may be associated with respective RMR IDs. The semi-static configuration may be implemented via system information and / or upper layer signaling (e.g., RRC). In some examples, the RMR may be dynamically activated and / or deactivated using an indication of an RMR ID. The indication of the RMR ID may be communicated using PHY layer signaling (e.g., DCI, or a control channel from another device).

[0169] "RMR", "RMR configuration", "RMR instantiation", "RMR activation", and "RMR deactivation" may be used interchangeably herein. Any aspect described herein as associated with any one or more of these terms is intended to be applicable to any other of these terms, as well as to any respective device, system, and method.

[0170] RMR, RMR configuration, and / or RMR instantiation may include an associated identifier, such as an RMR ID, that can identify each respective RMR, RMR configuration, and / or RMR instantiation.

[0171] RMR, RMR configuration, and / or RMR instantiation may include an RMR resource mapping. Such a resource mapping may include one or more of subcarriers and / or symbol locations. Such a resource mapping may also or instead include one or more of subframes that may be within a frame. Such a resource mapping may also or instead include one or more of a subframe offset, a TTI offset, each or both of which may be associated with subframe periodicity or TTI periodicity. Such a resource mapping may also or instead include one or more indications of antenna ports that may be associated with, for example, one or more beams by which an RMR may be received by a WTRU.

[0172] The RMR, RMR configuration, and / or RMR instantiation may include an RMR existence duration and / or an indication thereof. Such a configuration may be associated with a single instance of RMR (e.g., on one or more symbols that may be in one or more subframes). Such a configuration may also, or instead, be associated with multiple instances of RMR. The WTRU may be configured with RMR and may assume the presence of this RMR in one or more associated symbols and / or subframes. In some examples, such a WTRU may be configured to be periodic and may assume the presence of RMR until instructed by an associated TRP or other device to cease assuming the presence of RMR. Alternatively, or instead, the RMR configuration may include a period during which the configuration is valid. Such a period may be measured in symbols, subframes, frames, time units, or any other unit or measure.

[0173] The RMR, RMR configuration, and / or RMR instantiation may include an RMR frequency. The RMR configuration may be associated with a subband, a set of subcarriers, and / or a frequency block. The WTRU may be configured with RMR applicable to a set of subbands and may then be configured to remove (or deactivate) the RMR in a particular subband included within that set of subbands.

[0174] An RMR, RMR configuration, and / or RMR instantiation may include RMR measurement objectives and / or associated procedures, or instructions thereof. Such objectives and / or procedures may indicate one or more objectives for the WTRU of the RMR. For example, the RMR may be configured to be transmitted with one or more parallel data transmissions. Such an RMR configuration may include, for example, an association with the purpose of demodulation. For the same RMR, the RMR configuration may include, for example, an association with the purpose of CSI feedback. In such an example, the WTRU may determine an association between the measurement configuration and one or more procedures (e.g., demodulation, mobility, radio link monitoring, etc.).

[0175] An RMR, RMR configuration, and / or RMR instantiation may include an RMR measurement configuration. The RMR measurement configuration may indicate to the WTRU a relationship between a plurality of RMRs and / or a plurality of resources of the RMR (e.g., a plurality of resources of the RMR may be defined as each individual resource used within, for example, one instantiation of the RMR, and / or a plurality of resources of the RMR may be defined to be transmitted multiple times within a time period). The WTRU may be composed of a plurality of RMRs for which it may take the same measurement type with respect thereto. In such an example, the RMR measurement configuration may indicate to the WTRU that it may be assumed that a plurality of (e.g., all) RMRs represent the same instantaneous channel realization. Such a WTRU may perform short-term channel measurements. Alternatively, or instead, the RMR measurement configuration may indicate to the WTRU that it may be assumed that a configured set of RMRs (or a set of resources including the RMR) spans a plurality of channel realizations. In such an example, the WTRU may perform long-term channel statistics type measurements.

[0176] An RMR, RMR configuration, and / or RMR instantiation may include an RMR measurement configuration that may be associated with an RMR process. Such a process may be associated with a set of RMR instances. An RMR configuration (e.g., a dynamically signaled RMR configuration) may indicate an RMR process ID, for example, via an information element (IE). This IE may indicate to the WTRU whether measurements taken for the RMR can be combined (e.g., averaged) with measurements taken for previous RMR instances of the identified RMR process.

[0177] An RMR, RMR configuration, and / or RMR instantiation may include an indication of RMR dependency. A first RMR or RMR process may be configured with a dependency on, or association with, a second RMR or RMR process. The WTRU may modify its use of such a first RMR or RMR process based on the use of the WTRU of the second RMR or RMR process. For example, the WTRU may be configured with a first RMR or RMR process that has a purpose of channel estimation for demodulation. This first RMR or RMR process alone may not enable the WTRU to obtain sufficient channel estimation. The WTRU may be configured with a second RMR or RMR process with which it can perform one or more measurements that may improve the channel estimation performed using the first RMR or RMR process. The WTRU may obtain QCL information (e.g., Doppler shift, Doppler spread, mean delay, delay spread) for the second RMR or RMR process and use such QCL information associated with the second RMR when performing channel estimation for the first RMR or RMR process. Alternatively, or instead, the first RMR or RMR process may be configured as a reference RMR or RMR process that may be used with a second RMR or RMR process that is configured to have a dependency on the reference (first) RMR or RMR process.

[0178] An RMR, RMR configuration, and / or RMR instantiation may include an indication of one or more associated TRPs and / or WTRUs. This indication may indicate a source of a signal that can be measured. If the source of the signal that can be measured can be another WTRU, the TRP / WTRU value may correspond to, for example, L2 WTRU identification information that can be used for direct communication. If the source of the signal that can be measured can be an eNodeB, the TRP / WTRU value may correspond to, for example, a cell ID, TRP identification information, TRPG identification information, and / or access parameters thereof (e.g., from an access table and / or from system information).

[0179] One or more of the disclosed parameters of the RMR may be autonomously determined by the WTRU. The WTRU may autonomously determine that a set of RMRs or a set of resources including RMRs may cover an instantaneous channel realization form. Alternatively, or in addition, the WTRU may autonomously determine that a set of RMRs or a set of resources including RMRs may cover multiple channel realization forms. The WTRU may make such a determination based on, for example, the speed of the WTRU, the delay spread estimate, the coherence time, and / or the coherence bandwidth of the WTRU.

[0180] When the WTRU feeds back one or more measurements, it may indicate to the network one or more of the assumptions of the WTRU associated with the RMR configuration parameters (e.g., such one or more measurements may be associated with one or more respective values that may depend on one or more of the assumptions of the WTRU). A decision as to whether to provide such assumptions and / or measurements to the network may be made according to another measurement result, such as a result associated with the same or another set of RMRs. For example, the WTRU may measure the coherence time on a first set of RMRs and use that value to autonomously determine whether a second set of RMRs can cover a single channel realization form or multiple channel realization forms.

[0181] RMR configuration, activation, and / or deactivation may be indicated to the WTRU in a dynamic manner. For example, RMR configuration, activation, and / or deactivation may be TRP specific, group specific (e.g., for a subgroup of WTRUs served by the TRP and / or device), and / or WTRU specific. Such RMR configuration, activation, and / or deactivation may be indicated in a broadcast message.

[0182] An access table may be used to provide at least a portion of the system information associated with the TRP. The access table may include one or more elements that may be used to configure one or more RMRs.

[0183] The RMR may be configured in or by the WTRU specific transmission of the system information.

[0184] The RMR indication may be provided using a control channel and / or a portion thereof. For example, downlink control information (DCI) may be used to provide the RMR indication. The RMR configuration DCI may be transmitted to the WTRU or a group of WTRUs. Such DCI may include some or all of the RMR configuration.

[0185] The RMR may also or instead be used for cell specific purposes. The WTRU may be configured with a radio network temporary identifier (e.g., RMR-RNTI) that may be used to receive downlink control information (e.g., scheduling, activation, and / or deactivation) associated with the RMR for one or more purposes. A common RNTI may be used and configured for the WTRU. The purposes associated with the RMR may be one or more of performing mobility related measurements, performing positioning, performing radio link monitoring, and performing cell collection.

[0186] The WTRU may decode DCI associated with an RMR configuration in a common search space. Such DCI may indicate one or more characteristics of the RMR and / or a change in the activation state of the RMR. The DCI indication may be used to provide dynamic control of one or more transmissions for a common reference signal associated with one or more WTRUs and / or for any other one or more purposes.

[0187] The RMR indication using DCI may also provide information associated with one or more other transmissions. For example, DCI used for scheduling one or more DL transmissions may also include elements that may be used to configure, activate, and / or deactivate the RMR.

[0188] The RMR indication may be used for one or more cell-specific purposes. RMR-related control information may be included in DCI that may schedule and / or indicate another transmission (e.g., one or more multimedia broadcast multicast service (MBMS) transmissions), a separate positioning reference signal (PRS), and / or a system information broadcast.

[0189] The RMR indication may be implemented using a split DCI technique. For example, the WTRU may expect multi-step physical layer signaling (e.g., DCI). As used herein, "DCI" may refer to any physical layer signaling method.

[0190] The WTRU may expect a two-step DCI technique. FIG. 6 shows a diagram 600 illustrating an exemplary DCI configuration and activation / deactivation process. In block 651, a first DCI 610 (e.g., a long-term, wideband, and / or less frequent DCI, where the less frequent DCI may be applicable to multiple WTRUs) may be used to transmit the configuration of at least one RMR, such as RMRs 601 and 602. The configuration of the first DCI 610 may include one, a plurality (e.g., common to multiple WTRUs), or all RMR parameters (e.g., dedicated to a single WTRU). The first DCI 610 may also or instead indicate one or more RSs, such as RSs 631 and 632, that may be used as resources, for example, for one or more measurements.

[0191] In block 652, a second DCI 620 (e.g., a short-term, sub-band, and / or more frequently transmitted DCI applicable to a single WTRU or transmission) may be used to provide parameters for the same RMR for which parameters for it were provided in the first DCI 610, such as RMR 602. The second DCI 620 may indicate parameters associated with the RMR, such as RMR 602, that may change more frequently than the parameters shown in the first DCI 610 (e.g., also associated with RMR 602).

[0192] For example, the WTRU may receive, in the first DCI 610 in block 651, parameters for the RMR and / or a reference to a configuration associated with the RMR (e.g., RMR 602). Such a WTRU may determine whether the WTRU should perform further actions using such an RMR. In the example, reception of the second DCI 620 in block 652 (e.g., in or across a control region in a sub-band or a channel controlling the sub-band) may trigger such a WTRU to expect actual transmission of the RMR on the sub-band used by the second DCI 620 in some examples.

[0193] In block 652, the WTRU may receive a DCI, such as a second DCI 620, which may indicate that one or more RMRS, such as RMR 602, may be turned on (e.g., activated and / or applicable for associated transmissions) or turned off (deactivated). For example, the second DCI 620 may be used in block 652 to dynamically turn on and / or off RMR 602, e.g., on a particular time scale. Such a time scale may correspond to a symbol (or multiple thereof), a subframe and / or TTI (or multiple thereof), and / or a subband (or multiple thereof).

[0194] Based on a configuration that may include parameters such as, but not limited to, time, frequency, code, and / or space, a DCI, such as a second DCI 620, may be used to dynamically turn on and / or off one or both of RMRs, such as RMR 601 and RMR 602. Such parameters may be used to determine how and / or when to dynamically turn on and / or off the RMR. Alternatively, or in addition, a DCI, such as a second DCI 620, may indicate the purpose of the RMR for different subframes (or TTIs) and / or subbands.

[0195] The second DCI 620 may be used to change or adjust the parameters of an RMR, such as RMR 601, within a relatively short time frame. In an example, in block 653, the second DCI 620 may activate RMR 601 using one or more parameters, such as a fixed duration (e.g., lifespan). In such an example, the second DCI 620 may activate RMR 601 in block 654 using one or more parameters that may be different from the parameters used in block 653.

[0196] The second DCI 620 can be used to deactivate the RMR, such as the RMR 601. In the example, in block 655, the second DCI 620 can deactivate the RMR 601.

[0197] In block 656, the first DCI 610 can be used to transmit the configuration of at least one other RMR, such as the RMRs 603 and 604.

[0198] A second DCI, such as the second DCI 620, can be applicable in one or more combinations with a first DCI, such as the first DCI 610. A combination of an appropriate first DCI and an appropriate second DCI can be explicitly indicated (e.g., within the first and / or second DCI, such as the first DCI 610 and the second DCI 620). A first DCI, such as the first DCI 610, can include scheduling information and / or presence information (e.g., a presence indication) for a second DCI, such as the second DCI 620.

[0199] The relationship between the first DCI and the second DCI can be implicitly determined. A first DCI, such as the first DCI 610, can be associated with a set of one or more subbands, symbols, and / or subframes. A second DCI, such as the second DCI 620, that can be received by a WTRU within the set of subframes and / or subbands associated with such a first DCI can be assumed by such a WTRU to be associated with such a first DCI.

[0200] FIG. 7 shows a diagram 700 illustrating an exemplary DCI process. In block 710, a WTRU can transmit a request for one or more RSs, e.g., on the UL, where such a WTRU can determine that it may experience performance degradation. In the example, such a request may not be transmitted.

[0201] In block 720, DCI 721 may indicate RS 731 and RS 741 on the DL. DCI 721 may indicate that RS 731 and RS 741 may be resources used for CSI measurement. RS 731 may be provided in block 730, and RS 741 may be provided in block 740.

[0202] In block 750, a subsequent DCI 751 may request a CSI report 761 during the DL. In the example, RS 731 may be associated with a signal, and RS 741 may be associated with interference. Alternatively, RS 741 may be associated with a signal, and RS 731 may be associated with interference. In block 760, the CSI report 761 may be transmitted during the UL.

[0203] The WTRU may skip RMR activation. Such a WTRU may not perform one or more configured measurements. Measurements and / or channel estimation procedures (e.g., data demodulation, measurement feedback) associated with such RMR may be difficult to perform. In some examples, such measurement procedures may not be possible to perform. In such examples, the WTRU may report to, for example, one or more associated serving TRPs that it has failed to perform the associated procedures. Such a WTRU may indicate the cause of the failure as the absence of RMR.

[0204] A WTRU may escape RMR deactivation. Such a WTRU may continue to attempt to perform one or more measurements and / or other tasks associated with one or more objectives associated with the RMR from which deactivation was escaped. Such a WTRU may attempt to perform such one or more measurements and / or other tasks using one or more resources that the WTRU mistakenly anticipates the presence of the RMR. In an example, the WTRU may be able to determine an abnormal change in one or more measurements that may have been taken with respect to a first RMR instance based on a comparison with a second RMR instance that the WTRU may assume has a certain degree of dependence on the first RMR instance. Such a WTRU may report to the TRP that it has experienced an unexpected change. Based on such a report, the TRP may determine that the WTRU has not successfully received RMR deactivation.

[0205] The RMR process may include multiple RMR instances. The WTRU may anticipate the similarity of measurements taken based on different RMR instances of a first RMR process. If the measurements change by a threshold amount (which may be configurable), for example, the WTRU may determine that an unexpected change may be occurring and may provide an indication of such an unexpected change to the TRP.

[0206] The WTRU may use the RMR process for channel estimation and / or may determine that the signal strength has changed by more than a threshold amount that exceeds, for example, two consecutive RMR values. Such a WTRU may indicate such a determination to the TRP.

[0207] The WTRU may acknowledge receipt of RMR deactivation and / or RMR activation. The WTRU may acknowledge receipt of RMR deactivation and / or RMR activation for one or more long-term RMR processes. The WTRU may indicate one or more RMR instances for which feedback measurements may be applicable.

[0208] The presence of the RMR may be indicated to the WTRU in an implicit manner. For example, the WTRU may determine the presence of the RMR via implicit means. DCI that may allocate one or more DL resources may implicitly configure, activate (e.g., applicable to one or more transmissions), and / or indicate (e.g., applicable to associated transmissions) the presence of the RMR for use when demodulating one or more DL transmissions.

[0209] The presence of the RMR may be determined when the WTRU is requested to provide measurement feedback.

[0210] The reception of a second RMR may depend on the reception of a first RMR. For example, the WTRU may be configured and / or activated by a first RMR that may be included in or associated with a transmission, such configuration implicitly indicating the presence of the first RMR to the WTRU.

[0211] The reception of one or more reference signals, or one or more measurements therefor, for a second RMR may have a dependency on the reception of a first RMR. For example, the WTRU may be configured by a first RMR indicating a similar configuration and / or activation state (e.g., activation or presence) of the second RMR and / or may be activated in anticipation of its presence. Such a WTRU may receive and / or perform measurements on such a first RMR to determine results that may be used to trigger one or more measurements on such a second RMR.

[0212] The indication of the RMR may be implicitly determined, for example, based on a configured change in one or more transmission parameters. The WTRU may receive an indication and / or instruction to reconfigure the SOM, frame structure, and / or signal structure. The associated RMR may also be reconfigured. Such RMR reconfiguration may be pre-determined.

[0213] The RMR reconfiguration can be based on the functionality of the new signal structure. Alternatively, or in addition, the RMR configuration can be assumed to be associated with the signal structure. Such a change in the signal structure can indicate the deactivation of the associated RMR. The WTRU can store an RMR configuration for one or more transmission parameters (such as the signal structure). For example, when reconfigured to use a previously used set of transmission parameters, such a WTRU can reuse one or more previously configured RMRs and / or one or more RMR configurations associated with such a set of transmission parameters.

[0214] The RMR configuration can be associated with one or more TRPs, TRPGs, system signatures, cell identification information, etc., or any combination thereof. Reconfiguration of the WTRU that can modify one or more of such TRPs, TRPGs, system signatures, cell identification information, etc., or any combination thereof (such as a mobility event) can reconfigure the associated RMR configuration. For example, the WTRU can determine the applicable RMR configuration based on a pre-configuration and / or a list of RMR configurations, each of which can be associated with one or more TRPs, TRPGs, system signatures, cell identification information, etc., or any combination thereof.

[0215] An exemplary frame structure can be used for one or more DL and / or UL transmissions that can be transmitted to and / or received from the WTRU. Such an exemplary frame structure can include a preamble that can be transmitted by a TRP and received by the WTRU and / or another TRP. This preamble can be transmitted before and / or at the beginning of the frame structure, and in some examples, immediately before the beginning of the frame structure. Such a preamble can include an RMR that can be configured semi-statically. Such an RMR can enable the demodulation of information that can be transmitted within the preamble.

[0216] The preamble may include an RMR (e.g., an RMR that may be transmitted in parallel with the preamble) that can be used for one or more control regions that may be in at least one of a set of frames and / or sub-frames for which such a preamble can be transmitted. Alternatively, or instead, the preamble may include an indication to the WTRU that indicates and / or commands the WTRU to determine the presence and / or one or more parameters of an RMR that can be used for one or more control regions that may be in at least one of a set of frames and / or sub-frames for which such a preamble can be transmitted. Transmission of the preamble may include transmission of DCI, such as a first DCI and / or a second DCI, as described herein, without limitation.

[0217] The preamble may include a configuration for one or more RMRs. The RMR configuration associated with and / or included with such a preamble may be valid for a frame or set of frames for which the preamble can be transmitted. The RMR configuration associated with and / or included with such a preamble may be valid for a subset of the frames (or sub-frames) for which the preamble was transmitted. Transmission of the preamble may include transmission of DCI, such as a first DCI and / or a second DCI, as described herein, without limitation.

[0218] The WTRU may determine an RMR applicable for one or more downlink and / or uplink transmissions for one or more TRPs, TRPGs, system signatures, cell identification information, etc., or any combination thereof. Alternatively, or in addition, the WTRU may determine an RMR applicable for one or more downlink and / or uplink transmissions that may include a random access response (RAR) that may be a function of the transmission of a random access (RA) preamble. Alternatively, or in addition, the WTRU may determine an RMR applicable for transmissions that may include an RAR in response to one or more TRPs, identification information of TRPGs, system signatures, cell identification information, etc., or any combination thereof.

[0219] The RMR may be applicable until the WTRU may be reconfigured using the RMR (e.g., alternative RMR parameters) using dedicated signaling. Such an RMR may be applicable for transmissions associated with one or more procedures, e.g., for a random access procedure, for a mobility relation reconfiguration, during a mobility relation procedure, and / or until the WTRU may receive dedicated signaling for an applicable Uu association. For example, the WTRU may determine an applicable RMR according to one or more resources that may be used in time and / or frequency for the transmission of the RA preamble and / or according to the RMR used for the transmission of the RA preamble. Such a determination may be carried out according to the RA-RNTI applicable for the reception of the associated RAR. In an example, such a determination may be carried out in combination with applicable identification information.

[0220] The WTRU can be configured to determine (e.g., implicitly determine) the RMR based on one or more resources that can be used for data transmission and / or reception. The first WTRU can establish a connection with another (second) WTRU or, optionally, initiate communication therewith. The first and second WTRUs can determine a set of one or more resources that can be used to communicate with each other. One such WTRU that can be the transmitting WTRU can select a set of resources for one or more transmissions during a given time period (e.g., a scheduling period). The associated RMR can be valid for the duration of a given time period (e.g., a scheduling period). Alternatively, or in addition, the RMR can be defined as part of one or more resource definitions.

[0221] The WTRU can determine that it can use the transmission of one or more RMRs and / or the reconfiguration of one or more existing RMRs for various functions. The WTRU can support, for example, an on-demand PRS request mechanism for positioning purposes. Such a request can include and / or indicate one or more request parameters such as one or more of an applicable procedure, a desired accuracy, a speed estimate, etc. The WTRU can support an on-demand RMR request mechanism to implement WTRU autonomous mobility.

[0222] The WTRU can request the transmission of an RMR, for example, by transmitting an RMR request during UL transmission. The WTRU can have periodic UL resources on which it can request an RMR. Such a WTRU can transmit a signal when it desires the transmission of one or more RMRs and can remain silent when it does not desire the transmission of one or more RMRs. The WTRU can transmit a code point that can indicate whether the WTRU desires an RMR.

[0223] The WTRU may "piggyback" an RMR request on a UL transmission that may contain one or more requests, information, and / or any other data that is not an RMR request (e.g., the WTRU may transmit an RMR request in association with a UL transmission that may or may not be an RMR request in some cases). The WTRU may be granted UL resources for the transmission of data, and such a WTRU may add an RMR request to the granted UL resources. Alternatively, or in addition, the WTRU may have UL feedback that it desires to transmit, and it may add it to an RMR request that it may send along with the UL feedback and / or one or more UCI transmissions. In an example, the WTRU may transmit UL HARQ after a DL transmission. In an example, the WTRU may have feedback to report based on a previous RMR configuration. Such a WTRU may include, with such feedback, a request for a change in the RMR configuration using the transmission that gave such feedback. The WTRU may indicate to the TRP that the WTRU may desire to transmit one or more RMRs in one or more of the HARQ feedback resources.

[0224] The WTRU may use the UL control region to indicate a request for an RMR. The WTRU may autonomously schedule UL transmissions and may do so using the UL control region. A channel within the control region (or a field within the UCI transmitted in the UL control region) may be used by such a WTRU to request one or more RMR transmissions.

[0225] The WTRU request for an RMR may include one or more parameters of the RMR, such as an indication of the purpose of the RMR. Such a request may implicitly indicate one or more aspects of the RMR (e.g., by using the indication of the purpose of the RMR) depending on the resources (e.g., in terms of time, frequency, space, and / or applicable numerology), code points, and / or any other aspect that may be associated with the transmission of the request.

[0226] The WTRU may be triggered to request the transmission or reconfiguration of the RMR based on one or more various criteria and / or events. Such criteria and / or events may be a change in demodulation performance. If the WTRU may not always receive the RMR used for demodulation during every DL transmission, such a WTRU may determine the change in the SINR of the received DL transmission compared to the previous DL transmission.

[0227] The WTRU may determine that the performance of the WTRU's decoder has changed. Such a WTRU may be triggered to request a new or reconfigured RMR that may be used for channel estimation in the demodulation of one or more future and / or previous DL transmissions. For example, the WTRU may be scheduled with one or more DL transmissions and may determine that the channel estimation for it may be old. Such a WTRU may buffer one or more DL transmissions and may request the transmission of an RMR for use in demodulating such ones with one or more scheduled DL transmissions.

[0228] The WTRU may be triggered to request the transmission or reconfiguration of the RMR based on a request for retransmission. Such a WTRU may be triggered to request the RMR upon receiving a predetermined or dynamically determined number of NACKs for the same or multiple transport blocks. Such a WTRU may also, or instead, be triggered to request the RMR upon receiving a predetermined or dynamically determined number of NACKs received from the same or different TRPs. Such a WTRU may also, or instead, be triggered to request the reconfiguration of the RMR based on having received some NACKs for the same or multiple transport blocks or from the same or different TRPs. Such a requested reconfiguration may be associated with a density different from the density of the RMR being requested to be reconfigured. Such a density may enable and / or facilitate a performance different from the performance associated with the density of the RMR being requested to be reconfigured.

[0229] The WTRU may provide augmented HARQ feedback. The WTRU may include one or more channel estimation performance values (e.g., SINR, average SINR, variance of measurements, maximum measurement, minimum measurement) in the HARQ report. Such one or more channel estimation performance values may be included when the HARQ report is a NACK, and in some examples, when such HARQ report is a NACK for one or more specific retransmission values. The WTRU may, in an example, explicitly indicate in the HARQ feedback whether the WTRU desires an RMR or a change in the RMR configuration, where such RMR may be associated with one or more HARQ processes. The WTRU may indicate in the HARQ feedback report that it desires a new or modified RMR, where such new or modified RMR may be associated with a purpose. In an example, the WTRU may indicate that it desires a new or modified RMR associated with the purpose of performing one or more mobility measurements, e.g., due to the performance of one or more current transport block transmissions.

[0230] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on measurements of the RMR. In an example, the WTRU may be configured with a first RMR that may be used, for example, for coarse measurements. Such WTRU may use one or more triggers (e.g., based on one or more measurement thresholds) to determine whether a second RMR for performing finer measurements is required. One or more coarse measurements taken with respect to the first RMR or the first set of RMRs may or may not be fed back by the WTRU to the TRP. If the WTRU reports one or more coarser measurements, such report may be an implicit indication of the requirement for the second RMR or the second set of RMRs.

[0231] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on a narrowed selection of one or more transmission hypotheses. In an example, the WTRU may obtain one or more measurements of a first type for a first RMR or a first set of RMRs. Based on such one or more measurements, such a WTRU may be triggered to request a second RMR or a second set of RMRs that may be used to obtain one or more measurements of a second type for fewer transmission hypotheses than the first RMR or the first set of RMRs may support. In an example, the WTRU may measure coarse channel state information for a first set of beams that may be associated with a first RMR or a first set of RMRs. In some examples, such a WTRU may use such coarse channel state information measurements with one or more measurement thresholds to narrow the selection to a second set of potential beams having fewer beams than the first set of beams. Such a WTRU may request that the TRP transmit a second RMR or a second set of RMRs that may be associated with the second set of potential beams and / or that may enable one or more finer measurements.

[0232] The WTRU may be triggered to request transmission or reconfiguration of the RMR based on an indication from the TRP. The WTRU may receive from a first TRP an indication that may instruct the WTRU to report feedback on one or more measurements for a second TRP. The WTRU may determine interference that it may receive from the first TRP during one or more DL transmissions from the second TRP. Such a WTRU may request an RMR from the first TRP.

[0233] The WTRU may be triggered to request the transmission or reconfiguration of the RMR based on the transmission from the TRP. The WTRU may be capable of full-duplex radio. Such a WTRU may be scheduled to receive DL transmissions from a first TRP at the same, or a time proximate in time, at which the WTRU may also be scheduled to transmit UL transmissions to a second TRP. When scheduled for UL transmission to the second TRP, such a WTRU may request an RMR from the first TRP.

[0234] The WTRU may be triggered to request the transmission or reconfiguration of the RMR based on a change in the WTRU's RMR desire. Such a WTRU may desire a first RMR or a first set of RMRs associated with one or more first RMR parameters based on the status of the WTRU (e.g., speed). As the status of the WTRU changes (e.g., its speed changes), such a WTRU may desire a change in one or more RMR parameters, or a completely new set of one or more RMRs. The WTRU may change from using a first type of connection (e.g., an optical connection) that may use the first RMR, to using a second type of connection (e.g., a full connection) that may use the second RMR, and thus may request the transmission or reconfiguration of the RMR based on such a change.

[0235] The WTRU may be triggered to request the transmission or reconfiguration of the RMR based on the detection of a collision. The WTRU may be configured to determine when a resource collision occurs (e.g., on the sidelink) and may be configured to request an RMR associated with one or more networks and / or neighboring devices.

[0236] The WTRU can be triggered to request the transmission or reconfiguration of the RMR based on WTRU autonomous mobility. The WTRU can be configured to autonomously determine a suitable TRP, TRPG, system signature, and / or cell (e.g., a set thereof). Such a WTRU can initiate a request for the RMR when it initiates a selection procedure for such a suitable TRP, TRPG, system signature, and / or cell. Such a request for the RMR can correspond to the transmission of a preamble on a specific resource, such as a resource determined based on an access table.

[0237] The WTRU can be triggered to request the transmission or reconfiguration of the RMR based on the position of the WTRU. The WTRU can be configured to determine its position. The position of the WTRU that can be determined by the WTRU can be associated with a granularity and / or an error margin. The WTRU can initiate a request for the RMR (e.g., be triggered to initiate) when it determines that such a WTRU can improve its current position and / or acquire another position, e.g., a position that can be more granular, more specific, and / or have a lower error margin. The requested RMR can be used as a PRS, for example, when the position can be acquired and / or determined as the WTRU determines.

[0238] The WTRU can have, acquire, and / or determine a coarse position and / or coarse position information. Such a WTRU can further determine that additional refinement of such a coarse position and / or coarse position information can be performed. Such a WTRU can initiate a request, for example, for the purpose of increasing the frequency of such a PRS and / or for the purpose of having a PRS signal with one or more different characteristics (e.g., in time and / or in frequency). Such a determination for additional refinement can be based on the configuration of one or more RMRs for positioning purposes, where different RMR-PRSs can be associated with different granularities.

[0239] The WTRU may be triggered to request the transmission or reconfiguration of an RMR based on wireless link monitoring and / or wireless link recovery. The WTRU may determine that it has one or more wireless link problems and / or has experienced one or more wireless link problems. This determination may be based on any of a variety of measurements, including but not limited to measurements used for RMR, and measurements based on methods similar to those used in an LTE system (e.g., out-of-sync detection). In an example, the WTRU may determine that it may use one or more reference signals to perform wireless link and / or channel quality estimation, where such estimation may be used to address one or more wireless link problems. In such an example, in response to having made that determination, the WTRU may use one or more reference signals to perform wireless link and / or channel quality estimation to address one or more wireless link problems. For example, the WTRU may initiate a request for an RMR, for example, for recovery purposes and / or for confirmation of a wireless link problem.

[0240] The TRP may indicate the presence of an RMR requested by the WTRU in a manner similar to the manner described herein for any RMR indication. The TRP may indicate a positive response that a change has been made to one or more RMR parameters that may have been requested by the WTRU. For example, there may be one or more predetermined values of RMR density. The WTRU may be configured with a first value of RMR density. Such a WTRU may request a change to the RMR density to a second value. The TRP may transmit a positive response indicating that the requested change has been made without retransmitting all of the RMR configuration.

[0241] The WTRU may request one or more resources that it may use to transmit the RMR. Without limitation, an event such as any of the events described herein that may trigger a request from the WTRU for DL transmission of one or more RMRs may trigger such WTRU to request one or more resources that may be used to transmit the UL RMR. An event that may trigger the WTRU to request UL transmission of the RMR may be detected as a desire to transmit UL or SL data. In an example, the WTRU may be capable of autonomous transmission of data by the WTRU and may include the RMR to enable demodulation.

[0242] Without limitation, an event such as any of the events described herein may trigger the WTRU to autonomously perform UL transmission of the RMR. The WTRU may pre-configure the resources on which it may transmit an event-triggered UL RMR. Such resources may be configured for a set of WTRUs and / or may be contention-based. Each WTRU within such a set of WTRUs may have RMR transmission identification information. One or more parameters of the RMR transmission may depend on the WTRU identification information, for example, to facilitate contention resolution.

[0243] A WTRU may be configured to perform and / or report one or more measurements associated with one or more RMRs. The measurement configuration may be implemented in parallel with the configuration of one or more RMRs and / or in parallel with the configuration of one or more feedback resources. For example, a WTRU may be composed of measurements and / or one or more feedback resources, and such a WTRU may receive from a TRP an instruction to associate one or more measurements and / or one or more feedback resources with one or more RMRs. For example, a WTRU may be indicated (e.g., receive an indication message indicating them) of the existence of at least one instance of an RMR, at least one associated measurement (or measurement objective), and / or at least one instance of a feedback resource. In an example, the indication message may indicate one or more of each of the existence of an instance of an RMR, an associated measurement (or measurement objective), and an instance of a feedback resource.

[0244] The measurement configuration may be associated with RMRs that may be configured semi-statically. For example, RMRs located within a preamble or control channel may be configured semi-statically. The measurement configuration may also or alternatively be associated with RMRs that are dynamically controlled.

[0245] The measurement configuration may be used for periodic feedback, aperiodic feedback, and / or triggered feedback. The measurement configuration may include configuration and / or activation information for one or more RMRs. For example, a measurement feedback configuration may include and / or refer to one or more RMR configurations.

[0246] The measurement configuration may include a subset of the RMR configuration. The measurement configuration may be applied to a subset of the RMR resources. In an example, the RMR may be transmitted on resources across a plurality of subcarriers, and the measurement configuration may be applicable to a subset of such plurality of subcarriers. The RMR may be transmitted on resources that may span a plurality of symbols, subframes, and / or TTIs, and the measurement configuration may be applicable to a subset of the plurality of symbols, subframes, and / or TTIs.

[0247] The measurement configuration may include one or more WTRU rules for narrowing down and selecting one or more RMRs. The measurement configuration may be associated with the RMR and / or the RMR process. The WTRU may determine a subset of the RMR instances or RMR resources associated with the RMR configuration. Such a WTRU may perform one or more measurements on such a subset of the RMR instances or RMR resources. Such one or more measurements may each be a final measurement that may be reported back to the network. One or more rules that the WTRU may follow when narrowing down and selecting the RMR instances and / or RMR resources may be pre-determined, pre-configured, and / or dynamically configured and / or determined.

[0248] The measurement configuration may include an RMR measurement configuration. Such an RMR measurement configuration may indicate to the WTRU the relationship between a plurality of RMRs and / or a plurality of resources of the RMR (e.g., here, the plurality of resources of the RMR may be defined as each individual resource used to provide, for example, one instantiation of the RMR, or each instantiation of the RMR may be defined to be transmitted multiple times within a time period).

[0249] A WTRU can be composed of multiple RMRs, such that the WTRU can take the same measurement type based on each of them. The RMR measurement configuration can indicate to the WTRU that all of such multiple RMRs can represent the same instantaneous channel realization. In an example, the WTRU can perform short-term channel measurements. In an example, the RMR measurement configuration can indicate to the WTRU that a set of configured RMRs (or a set of resources associated with one or more RMRs) can span multiple channel realizations, or can be assumed to span multiple channel realizations. Such a WTRU can perform long-term channel measurements (e.g., long-term channel statistic type measurements).

[0250] A WTRU can be composed of an RMR process. Such an RMR process can be associated with a set of one or more RMR instances. A measurement configuration (e.g., a configuration provided by dynamic signaling) can indicate a set of RMR instances associated with such an RMR process that can be combined (e.g., averaged) to obtain measurements. Such a measurement configuration can indicate one or more RMRs, RMR processes, and / or RMR instances associated with the RMR and / or RMR process. Such a measurement configuration can indicate a measurement objective for at least one of the RMR, RMR process, or RMR instance. For example, such a measurement configuration can include multiple RMRs (or indications thereof), each of which can be associated with a different measurement objective (e.g., a first RMR can be used by the WTRU to measure signal strength, a second RMR can be used by the WTRU to measure Doppler, a third RMR can be used by the WTRU to measure channel occupancy, etc.).

[0251] The measurement configuration may include one or more measurement types. The measurement types may be similar to, but not necessarily the same as, the measurement objectives such as those described herein, without limitation. The measurement type may indicate to the WTRU that a (e.g., specific) CSI measurement may be performed on an associated RMR. The measurement type may be obtained based on the function of a set of measurements that one or more RMRs may take. For example, the WTRU may obtain a first measurement for a first RMR (or RMR process or RMR instance) and a second measurement for a second RMR (or RMR process or RMR instance). The measurement types indicated in the measurement configuration may indicate a function that the WTRU may use to combine the first measurement and the second measurement to determine or generate a third measurement for such a WTRU. Such a third measurement may be an intended result of the measurement configuration and / or may be used to determine whether a trigger event or criterion has been met, where such a trigger event or criterion, if met, may trigger a measurement report.

[0252] The measurement configuration may include one or more measurement feedback resources. Such one or more measurement feedback resources may be used by the WTRU, for example, to report periodic, aperiodic, and / or triggered feedback.

[0253] The measurement configuration may include an indication of the purpose of the measurement or associated procedure. The measurement configuration may indicate a single purpose associated with one or more RMRs and / or may be associated therewith. Alternatively, or in addition, the measurement configuration may indicate multiple purposes associated with one or more RMRs and / or may be associated therewith. In an example, the WTRU may determine an association between the measurement configuration and the procedure (e.g., demodulation, mobility, radio link monitoring, etc.).

[0254] The WTRU may store and / or optionally not maintain access to one or more measurements that the WTRU has made, accessed, and / or obtained. The measurement configuration may include one or more measurement triggers, each of which may trigger an associated WTRU to make one or more measurements.

[0255] A measurement trigger configured in a first measurement configuration may be associated with one or more results of one or more measurements that may be made based on a second measurement configuration. Such a second measurement configuration may configure the WTRU to make one or more measurements, including but not limited to, a set of long-term channel statistics on a second RMR that may be associated with the second measurement configuration. Based on such one or more such measurements and associated triggers, the WTRU may be triggered to make one or more measurements that may be configured in the first measurement configuration. Further, or alternatively, the WTRU may be triggered by a trigger that may be provided in the first measurement configuration. The measurement configuration may indicate to the WTRU a list of one or more measurements that may be independent RMRs, RMR processes, and / or RMR instances. Alternatively, such a list may be of one or more measurements that may not be independent RMRs, RMR processes, and / or RMR instances. The measurement configuration may indicate one or more measurement triggers that may be used to initiate a determination as to whether subsequent measurements should be acquired. In an example, the WTRU may be configured with a first measurement for a first RMR and a second measurement for a second RMR. Such a WTRU may also be configured with a measurement trigger that may be based on such a first measurement, such as, for example, a trigger based on achieving a threshold. When such a first measurement meets the trigger condition of such a measurement trigger, or optionally activates such a measurement trigger (e.g., here, such a first measurement meets or exceeds a threshold), the WTRU may perform and / or calculate a third measurement. Such a third measurement may be of a third RMR and / or a function of the first and / or second measurements.

[0256] In an example, the WTRU may receive downlink control information (e.g., DCI) that may trigger a measurement. Such DCI may include RMR configuration and / or identification information of an applicable RMR configuration. Such DCI may also, or instead, include scheduling information for a report that may be associated with the triggered measurement.

[0257] The measurement configuration may include one or more reporting triggers. The WTRU may not always report all measurements configured by the measurement configuration. Such a measurement configuration may provide one or more criteria that may be used to trigger the WTRU to report a measurement. In an example, the WTRU may receive downlink control information (e.g., DCI) that may trigger a measurement report. Such DCI may include identification information of an applicable RMR configuration. Such DCI may also, or instead, include scheduling information that may be associated with a report that may be associated with the triggered measurement.

[0258] The measurement configuration may include an indication of one or more associated TRPs, TRPGs, system signatures, cells, and device identification information. Such a measurement configuration may provide a set of TRPs or TRPs and / or a set of WTRUs or WTRU devices to which such measurements may apply.

[0259] The measurement configuration may include a random access configuration. The WTRU may be composed of one or more RMRs and / or information associated therewith. Each such RMR may assist or facilitate one or more of cell, TRP, TRPG, and / or system signature selection.

[0260] The WTRU may be composed of one or more access-related parameters, such as access rights, random access parameters, etc., any of which may also be associated with one or more configured RMRs in the WTRU or with the configured information. Such a WTRU may perform one or more measurements using such one or more RMR configurations or information. Such a WTRU may determine whether one or more of such measurements resulted in a favorable or in some cases compliant result.

[0261] Such a WTRU may compare or optionally use access relationship parameters associated with such an RMR to determine whether the configuration associated with the RMR can correspond to an associated cell, TRP, TRPG, and / or system signature. If such a cell, TRP, TRPG, and / or system signature is determined to correspond to such an RMR, the WTRU may use such parameters to initiate access to such an RMR and, in some instances, may perform a random access thereof. Such a WTRU may perform such a comparison and / or use of access relationship parameters to determine whether the configuration associated with any such RMR can correspond to a cell, TRP, TRPG, and / or system signature and to determine whether to initiate access (e.g., random access) to any such RMR using the associated parameters.

[0262] In a WTRU autonomous mobility example, the WTRU may use such an RMR to determine whether such a WTRU should consider the cell, TRP, TRPG, and / or system signature associated with the RMR as a serving cell, serving TRP, serving TRPG, and / or serving system signature (a "serving set"), respectively. Such a WTRU may determine that different RMRs should be associated with the serving cell, serving TRP, serving TRPG, and / or serving system signature.

[0263] When an RMR can be added to a serving set, the WTRU may determine whether a cell, TRP, TRPG, and / or system signature associated with such added RMR can be part of the same area as the cell, TRP, TRPG, and / or system signature previously associated with such serving set. If not, such WTRU may use access parameters associated with such added RMR to perform one or more functions, including but not limited to, for example, a location update that may be RAN-based.

[0264] The WTRU may be configured with a measurement configuration via upper layer signaling. The WTRU may be configured in a DL transmission mode. Such transmission mode may include one or more of a TTI duration, a signal structure, and an RMR. The measurement configuration may be applied in parallel with the transmission mode configuration. Such measurement configuration may provide an indication of the purpose of the RMR (e.g., demodulation).

[0265] The measurement configuration may be controlled dynamically. The dynamic measurement configuration may be implemented or in some cases implemented by DCI (or other control channel) that configures the RMR. The DCI may be transmitted in the control region to provide the measurement configuration. For example, a dedicated DCI that may be used for RMR configuration may be used for the measurement configuration. For example, a first (e.g., long term or wideband) DCI may configure one or more RMRs, and a second (e.g., short term or sub-band) DCI may provide one or more measurement configurations. Such one or more RMRs may exist across resources covered by such first DCI, and such one or more measurement configurations may be applied to resources (e.g., subframes or symbols, subcarriers, or sub-bands) covered by such second DCI.

[0266] The dynamic measurement configuration may be implemented or in some cases implemented by a DCI (or other control channel) that can schedule DL transmissions. The DCI that schedules DL transmissions may include an associated measurement configuration. Such a measurement configuration may be used to map the RMR that may be used for demodulation of the associated DL transmission.

[0267] The dynamic measurement configuration may be implemented or in some cases implemented by a MAC control element (“MAC CE”). The WTRU may receive a MAC CE that may include one or more measurement configurations. Such a MAC CE may be included in the RAR. Such a MAC CE may be received on a downlink transmission. The WTRU may determine that such one or more measurement configurations included with such a received MAC CE may be applicable to a SOM associated with a physical channel, transport channel, and / or control channel associated with the downlink transmission that included such a MAC CE.

[0268] The WTRU may report measurements within resources configured by the TRP. The configuration of the feedback resources may be performed within the measurement configuration. The WTRU may report information based on its own measurements and / or in place of, but not limited to, one or more purposes that may be described herein and for which the WTRU may perform measurements, such as reporting measurements that may address one or more purposes.

[0269] The WTRU may report values that may be based on the measurements performed. The purposes associated with such performed measurements may give rise to one or more various feedback reports, each of which may depend on the measurements performed. By way of example, the WTRU may report a quantized version of the measurements taken. By way of example, the WTRU may give a feedback report based on one or more measurement thresholds associated with one or more of the measurements obtained.

[0270] The WTRU may report different levels and / or types of channel utilization in response to the measurements taken. Such a WTRU may be comprised of an RMR (e.g., a blanked RMR) that attempts to detect interference and the type of interference. Such a WTRU may feedback the type of channel utilization that it may have encountered on the configured RMR. Alternatively, or in addition, such a WTRU may feedback the type of channel structure that it may have encountered on the configured RMR.

[0271] The values reported by the WTRU may be based on one or more sub-RMR measurements. The WTRU may be comprised of an RMR or RMR process on which it may perform one or more measurements. Such a WTRU may be configured to determine one or more subsets of the configured RMR or RMR process, or may determine it autonomously, and may perform one or more individual measurements on such one or more subsets. Such a WTRU may report an overall measurement (e.g., an average measurement) for all resources of the configured RMR or RMR process. Alternatively, or in addition, such a WTRU may report one or more individual sub-RMR or sub-RMR process measurements. In an example, the WTRU may be comprised of an RMR process on which interference is to be measured. Such a WTRU may determine that the interference is not uniform across the resources of the RMR process. Such a WTRU may feedback multiple interference values. Such interference values may be feedback with an indication of the respective associated RMR resources. Faster adaptation to channels with unexpected interference variations (e.g., due to URLLC transmissions) may be facilitated in such examples.

[0272] A WTRU may be composed of RMRs that can span multiple resources, where each such resource can be associated with a different antenna port. Such a WTRU may determine a subset of resources for which measurements may be valid for it. Such a WTRU may also, or instead, report to the network a subset of resources of RMRs and / or RMR processes for which measurements may be valid for it. In an example, such a WTRU may use one or more sub-RMR resource identifiers with such a report.

[0273] A WTRU may report one or more requests for one or more new and / or updated RMRs.

[0274] A WTRU may report one or more sets of RMRs and / or RMR sub-resources for which measurements may be valid. The WTRU may indicate whether such measurements may be assumed for a single channel realization or for the functionality of multiple channel realizations.

[0275] A WTRU may provide an indication of each RMR of one or more sets of RMRs, based on which such a WTRU may perform a function of determining and / or obtaining measurements that the WTRU may use to perform one or measurements that may be used to perform a function for which such a WTRU may use such first and second measurements to obtain a third measurement and / or result. Such a WTRU may be configured to perform a function of using such first and second measurements to obtain a third measurement and / or result. Such a WTRU may be composed of a first RMR for which a first measurement may be performed and a second RMR for which a second measurement may be performed.

[0276] A WTRU may report one or more sets of resources (e.g., symbols, subframes, subframe sets, TTIs, frames, time configurable units, subcarriers, subbands, configurable frequency blocks, etc.) for which measurements may be valid. Such a WTRU may report wideband and / or subband measurements. Such a WTRU may also, or instead, report long-term and / or short-term measurements. Measurement types (e.g., RI, CQI, PMI, etc.) that may be reported by such a WTRU may be defined similarly and / or separately for each of one or more long-term measurements and one or more short-term measurements. One or more long-term measurements may indicate the statistical performance of a channel. The WTRU may report the average usage of such a channel by other TRPs and / or WTRUs. One or more short-term measurements may indicate one or more instantaneous channel characteristics. The WTRU may report whether the channel may currently be in use.

[0277] The WTRU may report the reason for which a measurement may have been triggered. Such a report may indicate when the trigger may not be a function of the measurement. In an example, a first measurement may be reported by a second measurement that triggers the transmission of a feedback report.

[0278] The WTRU may report an RMR ID and / or associated TRP, TRPG, system signature, cell, and / or WTRU ID.

[0279] A feedback resource may be included during measurement configuration. The feedback resource may be transmitted independent of the measurement resource. In an example, the WTRU may receive an RMR configuration indicating activation of the RMR. Such a WTRU may receive a measurement configuration indicating activation of measurements to be performed on the RMR associated with the received RMR configuration. Such a WTRU may, in some examples, after receiving such a measurement configuration, receive a feedback resource configuration indicating one or more resources on which measurements may be feedbacked thereon.

[0280] A feedback resource and / or an indication thereof may be included during measurement configuration and / or given independently of the measurement resource, but the feedback resource may also or alternatively be configured by DCI. For example, the DCI may be defined to indicate one or more feedback resources to the WTRU. Such DCI may or may not be dedicated to indicating one or more feedback resources to the WTRU. A two-part approach may be used, where a first (e.g., long-term or wideband) DCI may be used to provide one or more feedback parameters, and a second (e.g., short-term or sub-band) DCI may be used to provide one or more other feedback parameters. Such a second DCI may be used to dynamically activate or deactivate one or more feedback resources on a subset of channel resources (e.g., a subset of the total bandwidth or a subset of symbols).

[0281] The feedback resource may also or alternatively be configured by and / or included with DCI used to grant UL resources. Such UL resources may be used for UL data transmission. Such UL resources may be used for the transmission of uplink control information (UCI).

[0282] The feedback resource may also or alternatively be configured by and / or included in DCI for standalone subframe transmission. Such DCI may be transmitted in the DL control region of a standalone subframe. Such DCI may serve one or more purposes. In an example, such DCI may allocate DL resources and / or UL feedback resources. Such DCI may include a feedback configuration that provides resources that may be used for feedback of measurements.

[0283] DCI can be used to dynamically activate or deactivate one or more feedback resources on a subset of channel resources (e.g., a subset of total bandwidth, a subset of symbols). DCI can indicate an index to a configuration that can be associated with one or more purposes, including but not limited to any of the purposes described herein.

[0284] A WTRU can be configured to report measurements (e.g., CSI reports) based on a set of dependent reference measurement resources, measurement configurations, and / or feedback resource configurations. The WTRU can also be configured by, or alternatively include, an indication of one or more reference measurement resources, measurement configurations, and / or feedback resource configurations, each of which can be independent. Such a configuration can be implemented in a semi-static manner, e.g., via higher layer signaling. The WTRU can have a set of reference measurement resources, a set of measurement configurations, and / or a set of feedback resources. Such a WTRU can be configured to dynamically associate one element (e.g., one reference measurement resource, one measurement configuration, and one feedback resource) from each such set with a measurement reporting process and / or measurement report.

[0285] A WTRU may be composed of at least two RMRs, each different and, in some examples, spanning independent resource elements (for illustrative purposes, RMR A and RMR B may be referred to herein as two examples of such at least two RMRs). Such a WTRU may be composed of, for example, two measurement configurations (e.g., a first measurement configuration "1" for long-term CSI reporting associated with a first set of measurement report triggers, and a second measurement configuration "2" for short-term CSI reporting associated with a second set of measurement report triggers). Such a WTRU may be composed of, for example, at least three feedback resources (for illustrative purposes, X, Y, Z may be referred to herein as three examples of such at least three feedback resources). Each such feedback resource may include or indicate a reporting occasion and / or a time / frequency / code / beam resource that may be different from the reporting occasion and / or the time / frequency / code / beam resource indicated in another such feedback resource.

[0286] Such a WTRU may be indicated or instructed to combine one or more resource elements, measurement configurations, and / or feedback resources dynamically and / or via a higher layer signal. Such a combination may sometimes be referred to as a measurement reporting process. In an example, a WTRU may be configured to combine RMR A, measurement configuration 2, and feedback resource Y into a measurement reporting process. The effectiveness of such a measurement reporting process may be applicable to a single occurrence of RMR transmission, measurement generation, and / or feedback transmission. Alternatively, the effectiveness of such a measurement reporting process may be applicable to multiple occurrences of each of RMR transmission, measurement generation, and / or feedback transmission (e.g., in a semi-persistent manner).

[0287] The configuration or indication of a measurement reporting process may indicate whether such a measurement reporting process is a one-shot (e.g., a one-time measurement resource, measurement configuration, and / or feedback report or any combination thereof), a multi-shot (e.g., a set of multiple measurement resources, measurement configurations, and / or feedback reports or combinations thereof), or periodic (e.g., a set of multiple periodic measurement resources, measurement configurations, and / or feedback reports or combinations thereof, each of which is valid and / or can be used until further reconfiguration). The configuration or indication of such a measurement reporting process may also, or instead, indicate the activation or deactivation of a multi-shot or periodic process.

[0288] A WTRU may be configured to perform one or more measurements on one or more RMRs. Such a WTRU may be configured with one or more triggers that the WTRU can use to determine whether such one or more measurements can be fed back. A measurement feedback trigger may be based on an associated measurement. In an example, the measurement feedback trigger may be based on whether an associated measurement value can meet or exceed an offset and / or threshold. In an example, the measurement feedback trigger may, in some examples, in addition to an offset, be based on whether an associated measurement value meets, is higher than, or is lower than another measurement value (e.g., a measurement value that can be obtained from another RMR).

[0289] Trigger criteria can be evaluated for each RMR or set of RMRs. In an example, the trigger criteria can be evaluated for some or all of the RMRs that are activated and / or associated with a given TRP, TRPG, system signature, cell, and / or WTRU. The WTRU can initiate transmission of feedback when the measured offset for a first RMR is "better" or otherwise favorable compared to the measured offset for a second RMR, e.g., by only an offset value, for example. Such first and second RMRs can be associated with the same TRP and / or cell.

[0290] One or more such measurements, triggers, and / or evaluations can be used, for example, for link adaptation purposes. The WTRU can initiate transmission of feedback when the first RMR can have a measured offset that meets or exceeds a threshold and / or when the measured offset for the first RMR is "better" or otherwise favorable compared to the measured offset for the second RMR. Such first RMR can be associated with a first TRP or set of TRPs (e.g., a first system signature). Such second RMR can be associated with a serving TRP or set of serving TRPs (e.g., a second system signature). Such feedback can be used for network-controlled mobility purposes.

[0291] One or more such measurements, triggers, and / or evaluations may be used, for example, to determine whether the TB has been successfully decoded. If the WTRU determines (e.g., using one or more such measurements, triggers, and / or evaluations) that the TB may not have been properly decoded and / or that a NACK may be required, the WTRU may be configured to perform one or more measurements on the RMR and may feedback one or more such measurements. In an example, such feedback may facilitate the TRP in performing link adaptation, for example, for retransmission of the TB.

[0292] The RMR may reuse one or more resources that may have been used for the transmission of the TB. The WTRU may use one or more data REs to perform one or more measurements. Such WTRU may be triggered to feedback one or more such measurements if the WTRU determines that the TB may have been properly decoded, for example, to ensure the validity of one or more measurements.

[0293] The WTRU may initiate a mobility relation procedure instead of or in addition to transmitting uplink feedback. Such initiation of the mobility relation procedure may be based on one or more measurements, triggers, and / or evaluations, as described herein.

[0294] Although features and elements have been described above in certain combinations, one of ordinary skill in the art will appreciate that each feature or element can be used alone or in any combination with other features and elements. Also, the methods described herein can be implemented in a computer program, 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, magnetic media such as ROM, RAM, registers, cache memory, semiconductor memory devices, internal hard disks, and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). Processors associated with software can be used to implement radio frequency transceivers for use in a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. 1. A wireless transmit / receive unit (WTRU) comprising a processor and a memory, the processor and the memory comprising: transmitting a request for one or more reference measurement resources (RMRs) for measuring a positioning reference signal (PRS), the request including one or more parameters associated with the RMRs, an identifier (ID) associated with the one or more RMRs; receiving a response to the request; and transmitting a measurement report based on the received PRS; A WTRU configured to perform the following:

2. The WTRU of claim 1 , wherein the one or more parameters include an RMR periodicity, an RMR frequency sub-band, an RMR element mapping, beam information, or a time period associated with a start time or duration of the PRS.

3. The WTRU of claim 2 , wherein the RMR element mapping comprises mapping a set of resource elements (REs) to one or more symbols and one or more subcarriers.

4. The WTRU of claim 2 , wherein the RMR periodicity is measured in units of time, symbols, frames, or subframes.

5. The WTRU of claim 1 , wherein the processor and memory are further configured to support an on-demand PRS request mechanism.

6. The WTRU of claim 5 , wherein the one or more parameters include a procedure for performing the on-demand PRS request mechanism, a desired accuracy, or a speed estimate.

7. The WTRU of claim 1 , wherein the RMR includes one or both of a non-zero power reference signal or a zero power reference signal.

8. The WTRU of claim 2 , wherein the beam information includes an indication that multiple RMRs are multiplexed onto overlapping resources using different beams.

9. The WTRU of claim 1 , wherein the processor and memory are further configured to receive the RMR dynamically, semi-statically, or statically.

10. The WTRU of claim 1 , wherein the processor and memory are further configured to indicate the RMR via higher layer signaling.

11. 1. A method performed by a wireless transmit / receive unit (WTRU), comprising: transmitting a request for one or more reference measurement resources (RMRs) for measuring a positioning reference signal (PRS), the request including one or more parameters associated with the RMRs, an identifier (ID) associated with the one or more RMRs; receiving a response to the request; and transmitting a measurement report based on the received PRS; A method for providing the above.

12. 12. The method of claim 11, wherein the one or more parameters include an RMR periodicity, an RMR frequency sub-band, an RMR element mapping, beam information, or a time period associated with a start time or duration of the PRS.

13. The method of claim 12 , wherein the RMR element mapping comprises mapping a set of resource elements (REs) to one or more symbols and one or more subcarriers.

14. The method of claim 12 , wherein the RMR periodicity is measured in units of time, symbols, frames, or subframes.

15. The method of claim 11 , further comprising supporting an on-demand PRS request mechanism.

16. The method of claim 15 , wherein the one or more parameters include a procedure, a desired accuracy, or a speed estimate for executing the on-demand PRS request mechanism.

17. The method of claim 11 , wherein the RMR includes one or both of a non-zero power reference signal or a zero power reference signal.

18. The method of claim 12 , wherein the beam information includes an indication that multiple RMRs are multiplexed onto overlapping resources using different beams.

19. The method of claim 11 , further comprising receiving the RMR dynamically, semi-statically, or statically.

20. The method of claim 11 , further comprising indicating the RMR via higher layer signaling.

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