WTRU measurement method in energy-saving network

Abstract

The present systems and methods include WTRU measurements, mobility, carrier reselection for a WTRU capable of operating in a network employing energy saving technology. The systems and methods include connected mode procedures / behaviors, including mobility and related measurements, for a WTRU operating in an NES cell. The systems and methods include idle / inactive mode procedures / behaviors, such as cell reselection, for the WTRU. The present systems and methods include mobility and cell reselection measurement methods for triggering inter-cell / inter-frequency / inter-RAT measurements when determining that the NES state changes.

Description

[0001] Cross - Reference to Related Applications

[0002] This application claims the benefit of U.S. Provisional Application Serial No. 63 / 410,971, filed on September 28, 2022, and U.S. Provisional Application Serial No. 63 / 445,568, filed on February 14, 2023, which are hereby incorporated by reference in their entirety as if fully set forth herein. Background Art

[0003] There is a motivation to research enhancement functions to enable a network to minimize its power consumption from transmission and reception. Such minimization is beneficial for reducing operating costs and for environmental sustainability. Compared to earlier systems, the NR design is very efficient in terms of minimizing transmission from the network when there is no data. For example, always - on cell - specific reference signals (CRS) are not used in NR. However, there is still potential for reducing energy consumption. Summary of the Invention

[0004] The present system and method include WTRU measurements, mobility, and carrier reselection for a WTRU capable of operating in a network employing energy - saving techniques. The system and method include connection - mode procedures / behaviors for a WTRU operating in an NES cell, including mobility and related measurements. The system and method include idle / inactive - mode procedures / behaviors for a WTRU, such as cell reselection. The present system and method include mobility and cell - reselection measurement methods for triggering inter - cell / inter - frequency / inter - RAT measurements when determining a change in the NES state. Brief Description of the Drawings

[0005] A more detailed understanding can be obtained from the following description given by way of example in conjunction with the accompanying drawings, in which like reference numerals in the figures represent like elements, and in which:

[0006] Figure 1A is a system diagram showing an exemplary communication system in which one or more disclosed embodiments can be implemented;

[0007] Figure 1B is a system diagram showing an exemplary wireless transmit / receive unit (WTRU) that can be used within the Figure 1A shown communication system according to an embodiment;

[0008] Figure 1C is a system diagram showing an exemplary radio access network (RAN) and an exemplary core network (CN) that can be used within the Figure 1A shown communication system according to an embodiment;

[0009] Figure 1D is a system diagram showing an exemplary one that can be used within the Figure 1ASystem diagram of another exemplary RAN and another exemplary CN used within the shown communication system;

[0010] Figure 2 Illustrates the time-frequency structure of the SSB;

[0011] Figure 3 Example of beam scanning;

[0012] Figure 4 Illustrates conditional handover configuration and execution;

[0013] Figure 5 Illustrates the procedures for cell selection and reselection;

[0014] Figure 6 Illustrates an example;

[0015] Figure 7 Illustrates the WTRU measurement method in an energy-saving network; and

[0016] Figure 8 Illustrates the method executed in the WTRU. Detailed Description

[0017] As described above, there is a need for enhanced functionality to enable the network to minimize its power consumption from transmission and reception. This minimization is beneficial for reducing operating costs and for environmental sustainability. Compared to earlier systems, the current design of NR is very efficient in terms of minimizing transmissions from the network when there is no data. For example, always-on cell-specific reference signals (CRSs) are not used in NR. There is still potential for additional energy consumption reduction.

[0018] For example, when the network is not transmitting, it also consumes energy due to other activities such as baseband (digital) processing for reception or beamforming. This "idle" power consumption is not negligible in a dense network even when no WTRU is being served during a given period. If the network can turn off these activities when not transmitting to the WTRU, energy consumption can be reduced.

[0019] In addition, NR supports beamforming using a large number of ports (up to 64 transmit and receive ports), and the energy consumption increases with the number of ports used. In fact, the utilization of the maximum number of ports may not be necessary for all WTRUs. If the network only adjusts the number of ports to the required amount, energy consumption can be reduced.

[0020] Network energy saving can aim to improve the operation of the cellular ecosystem to enable more efficient adaptation of network transmission and reception resources in the time, frequency, space, and power domains, and can obtain support, feedback, and assistance from the WTRU. This enables echo-friendly WTRU operation, thereby allowing for a more environmentally friendly network deployment, which in turn allows for a reduction in the emissions and Opex costs of operating the cellular network. Different from LTE, NR does not require the transmission of always-on synchronization or reference signals and supports adaptable bandwidth and MIMO capabilities. Although the initial work in this area is not expected to affect traditional WTRUs, it is also recognized that the adaptability of network resources can enable the deployment of operational updates and higher efficiency in later generations.

[0021] A system, a WTRU, and a method for performing WTRU measurements in an energy-saving network are described. The method can be performed in a wireless transmit / receive unit (WTRU). The method includes: receiving configuration information indicating one or more measurement configurations, where each of the one or more measurement configurations includes NES status information indicating one or more network energy saving (NES) states to which the measurement configuration can apply; receiving signaling associated with activating a first NES state among the indicated one or more NES states; determining, based on the received information, a measurement configuration that can apply to the first NES state; performing one or more measurements using the determined measurement configuration; and reporting the one or more measurements. The measurements are performed within a time period configured for the first NES state. The measurements are reported within a time period configured for the first NES state. The signaling associated with activating the first NES state can indicate at least one selected from the group consisting of the activation of the first NES state, when the first NES state is to be activated, and the time period during which the first NES state can be activated. The signaling associated with activating the first NES state can include a conditional handover (CHO) configuration associated with the first NES state. The signaling associated with activating the first NES state can include a conditional handover (CHO) reconfiguration associated with the first NES state. The method can include receiving signaling associated with activating a second NES state among the indicated one or more NES states. The method can include deactivating the first NES state and can include using one or more measurement configurations not associated with any NES state. The one or more measurements can include at least one measurement of an adjacent cell.

[0022] A wireless transmit / receive unit (WTRU) includes a processor and a transceiver communicatively coupled to the processor. The processor and the transceiver are operative to receive configuration information indicating one or more measurement configurations, wherein each of the one or more measurement configurations includes NES status information indicating one or more network energy saving (NES) states to which the measurement configuration may be applicable, receive signaling associated with activating a first NES state of the one or more indicated NES states, determine, based on the received information, a measurement configuration that may be applicable to the first NES state, perform one or more measurements using the determined measurement configuration, and report the one or more measurements. The measurements may be performed within a time period configured for the first NES state. The measurements may be reported within a time period configured for the first NES state. The signaling associated with activating the first NES state may indicate at least one selected from the group consisting of an activation of the first NES state, when the first NES state is to be activated, and a time period during which the first NES state may be activated. The signaling associated with activating the first NES state may include a conditional handover (CHO) configuration associated with the first NES state. The signaling associated with activating the first NES state may include a conditional handover (CHO) reconfiguration associated with the first NES state. The processor and the transceiver may also be configured to receive signaling associated with activating a second NES state of the one or more indicated NES states. The processor and the transceiver may also be configured to deactivate the first NES state. The processor and the transceiver may also be configured to utilize one or more measurement configurations not associated with any NES state. The one or more measurements may include at least one measurement of a neighboring cell.

[0023] Figure 1A FIG. is a diagram illustrating an exemplary communication system 100 in which one or more disclosed embodiments may be implemented. The communication system 100 may be a multi-access system that provides content, such as voice, data, video, messaging, broadcast, etc., to a plurality of wireless users. The communication system 100 may enable the plurality of wireless users to access such content through a shared system resource including wireless broadband. For example, the communication system 100 may employ one or more channel access methods, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), single-carrier FDMA (SC-FDMA), zero-tail unique word discrete Fourier transform spread OFDM (ZT-UW-DFT-S-OFDM), unique word OFDM (UW-OFDM), resource block filtered OFDM, filter bank multicarrier (FBMC), etc.

[0024] As Figure 1AAs shown, the communication system 100 may include wireless transmit / receive units (WTRUs) 102a, 102b, 102c, 102d, a radio access network (RAN) 104, a core network (CN) 106, a public switched telephone network (PSTN) 108, the Internet 110, and other networks 112. However, it will be understood that the disclosed embodiments contemplate any number of WTRUs, base stations, networks, and / or network elements. Each of the WTRUs 102a, 102b, 102c, 102d may be any type of device configured to operate and / or communicate in a wireless environment. For example, the WTRUs 102a, 102b, 102c, 102d (any of which may be referred to as a station (STA)) may be configured to transmit and / or receive wireless signals and may include user equipment (UE), mobile stations, fixed or mobile subscriber units, subscription-based units, pagers, cellular telephones, personal digital assistants (PDAs), smartphones, laptop computers, netbooks, personal computers, wireless sensors, hotspots or Mi-Fi devices, Internet of Things (IoT) devices, watches or other wearable devices, head-mounted displays (HMDs), vehicles, drones, medical devices and applications (e.g., remote surgery), industrial devices and applications (e.g., robots and / or other wireless devices operating in the context of an industrial and / or automated processing chain), consumer electronic devices, devices operating on commercial and / or industrial wireless networks, etc. Any of the WTRUs 102a, 102b, 102c, 102d may be interchangeably referred to as a UE.

[0025] The communication system 100 may also include base stations 114a and / or base stations 114b. Each of the base stations 114a, 114b may be any type of device configured to wirelessly interface with at least one of the WTRUs 102a, 102b, 102c, 102d to facilitate access to one or more communication networks such as the CN 106, the Internet 110, and / or other networks 112. For example, the base stations 114a, 114b may be base transceiver stations (BTSs), NodeBs, eNodeBs (eNBs), home NodeBs, home eNode Bs, next-generation NodeBs, such as gNode Bs (gNBs), new radio (NR) NodeBs, site controllers, access points (APs), wireless routers, etc. Although each of the base stations 114a, 114b is depicted as a single element, it will be understood that the base stations 114a, 114b may include any number of interconnected base stations and / or network elements.

[0026] Base station 114a may be part of RAN 104, which may also include other base stations and / or network elements (not shown), such as base station controllers (BSCs), radio network controllers (RNCs), relay nodes, etc. Base station 114a and / or base station 114b may be configured to transmit and / or receive wireless signals on one or more carrier frequencies, which may be referred to as a cell (not shown). These frequencies may be in licensed spectrum, unlicensed spectrum, or a combination of licensed and unlicensed spectrum. A cell may provide wireless service coverage to a specific geographical area that may be relatively fixed or may change over time. A cell may also be divided into cell sectors. For example, the cell associated with base station 114a may be divided into three sectors. Thus, in one embodiment, base station 114a may include three transceivers, i.e., one transceiver for each sector of the cell. In one embodiment, base station 114a may employ multiple-input multiple-output (MIMO) technology and may utilize multiple transceivers for each sector of the cell. For example, beamforming may be used to transmit and / or receive signals in a desired spatial direction.

[0027] Base stations 114a, 114b may communicate with one or more of WTRUs 102a, 102b, 102c, 102d via air interface 116, which may be any suitable wireless communication link (e.g., radio frequency (RF), microwave, centimeter wave, millimeter wave, infrared (IR), ultraviolet (UV), visible light, etc.). Any suitable radio access technology (RAT) may be used to establish air interface 116.

[0028] More specifically, as described above, communication system 100 may be a multiple access system and may employ one or more channel access schemes, such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, etc. For example, base station 114a in RAN 104, as well as WTRUs 102a, 102b, 102c, may implement radio technologies, such as Universal Mobile Telecommunications System (UMTS) Terrestrial Radio Access (UTRA) that may use Wideband CDMA (WCDMA) to establish air interface 116. WCDMA may include communication protocols such as High Speed Packet Access (HSPA) and / or Evolved HSPA (HSPA+). HSPA may include High Speed Downlink (DL) Packet Access (HSDPA) and / or High Speed Uplink (UL) Packet Access (HSUPA).

[0029] In an embodiment, base station 114a and WTRUs 102a, 102b, 102c may implement radio technologies such as evolved UMTS terrestrial radio access (E-UTRA) which may use Long Term Evolution (LTE) and / or LTE-Advanced (LTE-A) and / or LTE-Advanced Pro (LTE-A Pro) to establish the air interface 116.

[0030] In an embodiment, base station 114a and WTRUs 102a, 102b, 102c may implement radio technologies such as NR radio access which may use NR to establish the air interface 116.

[0031] In an embodiment, base station 114a and WTRUs 102a, 102b, 102c may implement multiple radio access technologies. For example, base station 114a and WTRUs 102a, 102b, 102c may jointly implement LTE radio access and NR radio access using, for example, the dual connectivity (DC) principle. Thus, the air interface used by WTRUs 102a, 102b, 102c may be characterized by multiple types of radio access technologies and / or transmissions to / from multiple types of base stations (e.g., eNBs and gNBs).

[0032] In other embodiments, base station 114a and WTRUs 102a, 102b, 102c may implement radio technologies such as IEEE 802.11 (i.e., Wi-Fi), IEEE 802.16 (i.e., WiMAX), CDMA2000, CDMA2000 1X, CDMA2000 EV-DO, Interim Standard 2000 (IS-2000), Interim Standard 95 (IS-95), Interim Standard 856 (IS-856), Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE), GSM EDGE (GERAN), etc.

[0033] Figure 1AThe base station 114b therein may be, for example, a wireless router, a home NodeB, a home eNode B, or an access point, and may utilize any suitable RAT to facilitate wireless connections in a local area such as a commercial venue, a home, a vehicle, a campus, an industrial facility, an air corridor (e.g., for drones), a road, etc. In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.11 to establish a wireless local area network (WLAN). In one embodiment, the base station 114b and the WTRUs 102c, 102d may implement a radio technology such as IEEE 802.15 to establish a wireless personal area network (WPAN). In yet another embodiment, the base station 114b and the WTRUs 102c, 102d may utilize a cellular-based RAT (e.g., WCDMA, CDMA2000, GSM, LTE, LTE-A, LTE-A Pro, NR, etc.) to establish a pico cell or a femto cell. As Figure 1A shown, the base station 114b may be directly connected to the Internet 110. Thus, the base station 114b may not need to access the Internet 110 via the CN 106.

[0034] The RAN 104 may communicate with the CN 106, which may be any type of network configured to provide voice, data, applications, and / or voice over Internet Protocol (VoIP) services to one or more of the WTRUs 102a, 102b, 102c, 102d. The data may have different quality of service (QoS) requirements, such as different throughput requirements, latency requirements, fault tolerance requirements, reliability requirements, data throughput requirements, mobility requirements, etc. The CN 106 may provide call control, billing services, location-based services for mobile devices, prepaid calls, Internet connections, video distribution, etc., and / or perform advanced security functions, such as user authentication. Although Figure 1A not shown, it will be appreciated that the RAN 104 and / or the CN 106 may communicate directly or indirectly with other RANs employing the same RAT as the RAN 104 or a different RAT. For example, in addition to being connected to the RAN 104 that may be utilizing NR radio technology, the CN 106 may also communicate with another RAN (not shown) employing GSM, UMTS, CDMA 2000, WiMAX, E-UTRA, or WiFi radio technology.

[0035] CN 106 can also serve as a gateway for the WTRU 102a, 102b, 102c, 102d to access the PSTN 108, the Internet 110, and / or other networks 112. The PSTN 108 may include a circuit-switched telephone network that provides plain old telephone service (POTS). The Internet 110 may include a global system of interconnected computer networks and devices that use common communication protocols such as Transmission Control Protocol (TCP), User Datagram Protocol (UDP), and / or Internet Protocol (IP) in the TCP / IP Internet protocol suite. The network 112 may include wired and / or wireless communication networks owned and / or operated by other service providers. For example, the network 112 may include another CN connected to one or more RANs, and the other CN may employ the same RAT as the RAN 104 or a different RAT.

[0036] Some or all of the WTRU 102a, 102b, 102c, 102d in the communication system 100 may include multi-mode capabilities (e.g., the WTRU 102a, 102b, 102c, 102d may include multiple transceivers for communicating with different wireless networks over different wireless links). For example, Figure 1A the illustrated WTRU 102c may be configured to communicate with a base station 114a that may employ a cellular-based radio technology and with a base station 114b that may employ IEEE 802 radio technology.

[0037] Figure 1B is a system diagram showing an exemplary WTRU 102. As Figure 1B shown, the WTRU 102 may include a processor 118, a transceiver 120, transmit / receive elements 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 Global Positioning System (GPS) chipset 136, and / or other peripheral devices 138, etc. It will be appreciated that the WTRU 102 may include any sub-combination of the foregoing elements while remaining consistent with the embodiments.

[0038] The processor 118 can be a general-purpose processor, a dedicated processor, a conventional processor, a digital signal processor (DSP), multiple microprocessors, one or more microprocessors associated with a DSP core, a controller, a microcontroller, an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) circuit, any other type of integrated circuit (IC), a state machine, etc. The processor 118 can perform signal encoding, data processing, power control, input / output processing, and / or any other functions that enable the WTRU 102 to operate in a wireless environment. The processor 118 can be coupled to a transceiver 120, which can be coupled to a transmit / receive element 122. Although Figure 1B the processor 118 and the transceiver 120 are depicted as separate components, it will be appreciated that the processor 118 and the transceiver 120 can be integrated together in an electronic package or chip.

[0039] The transmit / receive element 122 can be configured to transmit signals to or receive signals from a base station (e.g., base station 114a) via an air interface 116. For example, in one embodiment, the transmit / receive element 122 can be an antenna configured to transmit and / or receive RF signals. In one embodiment, for example, the transmit / receive element 122 can be a transmitter / detector configured to transmit and / or receive, for example, IR, UV, or visible light signals. In another embodiment, the transmit / receive element 122 can be configured to transmit and / or receive both RF signals and optical signals. It will be appreciated that the transmit / receive element 122 can be configured to transmit and / or receive any combination of wireless signals.

[0040] Although the transmit / receive element 122 is depicted as a single element in Figure 1B the WTRU 102 can include any number of transmit / receive elements 122. More specifically, the WTRU 102 can employ MIMO technology. Thus, in one embodiment, the WTRU 102 can include two or more transmit / receive elements 122 (e.g., multiple antennas) for transmitting and receiving wireless signals via the air interface 116.

[0041] The transceiver 120 can be configured to modulate the signals to be transmitted by the transmit / receive element 122 and demodulate the signals received by the transmit / receive element 122. As described above, the WTRU 102 can have multi-mode capabilities. Thus, the transceiver 120 can include multiple transceivers for enabling the WTRU 102 to communicate via multiple RATs (e.g., such as NR and IEEE 802.11).

[0042] The processor 118 of the WTRU 102 can be coupled to and can receive user input data from: a speaker / microphone 124, a keypad 126, and / or a display / touchpad 128 (e.g., a liquid crystal display (LCD) display unit or an organic light emitting diode (OLED) display unit). The processor 118 can also output user data to the speaker / microphone 124, the keypad 126, and / or the display / touchpad 128. Additionally, the processor 118 can access information from and store data in any type of suitable memory such as a non-removable memory 130 and / or a removable memory 132. The non-removable memory 130 can include random access memory (RAM), read-only memory (ROM), a hard disk, or any other type of memory storage device. The removable memory 132 can include a subscriber identity module (SIM) card, a memory stick, a secure digital (SD) memory card, etc. In other embodiments, the processor 118 can access information from and store data in a memory that is not actually located on the WTRU 102, such as on a server or a home computer (not shown).

[0043] The processor 118 can receive power from a power supply 134 and can be configured to distribute power to and / or control the power to other components in the WTRU 102. The power supply 134 can be any suitable device for powering the WTRU 102. For example, the power supply 134 can include one or more dry cells (e.g., nickel cadmium (NiCd), nickel zinc (NiZn), nickel metal hydride (NiMH), lithium ion (Li-ion), etc.), a solar cell, a fuel cell, etc.

[0044] The processor 118 can also be coupled to a GPS chipset 136, which can 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 information from the GPS chipset 136, the WTRU 102 can receive location information from a base station (e.g., base stations 114a, 114b) via an air interface 116 and / or can 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 can obtain location information by any suitable location determination method while remaining consistent with the embodiments.

[0045] The processor 118 can also be coupled to other peripheral devices 138, which can include one or more software and / or hardware modules that provide additional features, functionality, and / or wired or wireless connections. For example, the peripheral devices 138 can include an accelerometer, an electronic compass, a satellite transceiver, a digital camera (for photos and / or videos), a universal serial bus (USB) port, a vibration device, a television transceiver, a hands-free headset, Modules, FM radio units, digital music players, media players, video game player modules, Internet browsers, virtual reality and / or augmented reality (VR / AR) devices, activity trackers, etc. Peripheral device 138 may include one or more sensors. The sensors may be one or more of a gyroscope, an accelerometer, a Hall effect sensor, a magnetometer, an orientation sensor, a proximity sensor, a temperature sensor, a time sensor; a geographical location sensor, an altimeter, a light sensor, a touch sensor, a magnetometer, a barometer, a gesture sensor, a biometric sensor, a humidity sensor, etc.

[0046] The WTRU 102 may include a full-duplex radio, where some or all of the transmission and reception of signals (e.g., associated with a particular subframe for both UL (e.g., for transmission) and DL (e.g., for reception)) may be concurrent and / or simultaneous. The full-duplex radio may include an interference management unit to reduce and / or substantially eliminate self-interference via hardware (e.g., a choke) or signal processing via a processor (e.g., a separate processor (not shown) or via processor 118). In one embodiment, the WTRU 102 may include a half-duplex radio, where some or all of the transmission and reception of signals (e.g., associated with a particular subframe for either UL (e.g., for transmission) or DL (e.g., for reception)).

[0047] Figure 1C is a system diagram showing the RAN 104 and the CN 106 according to an embodiment. As described above, the RAN 104 may employ E-UTRA radio technology to communicate with the WTRU 102a, 102b, 102c via the air interface 116. The RAN 104 may also communicate with the CN 106.

[0048] The RAN 104 may include eNode-Bs 160a, 160b, 160c, but it will be understood that the RAN 104 may include any number of eNode-Bs while remaining consistent with the embodiment. The eNode-Bs 160a, 160b, 160c may each include one or more transceivers for communicating with the WTRU 102a, 102b, 102c via the air interface 116. In one embodiment, the eNode-Bs 160a, 160b, 160c may implement MIMO technology. Thus, for example, the eNode-B 160a may use multiple antennas to transmit wireless signals to and / or receive wireless signals from the WTRU 102a.

[0049] Each of eNode-Bs 160a, 160b, and 160c may be associated with a particular cell (not shown) and may be configured to handle radio access network resource management decisions, handover decisions, user scheduling in the UL and / or DL, etc. As Figure 1C shown, eNode-Bs 160a, 160b, and 160c may communicate with each other via the X2 interface.

[0050] Figure 1C The CN 106 shown may include a Mobility Management Entity (MME) 162, a Serving Gateway (SGW) 164, and a Packet Data Network (PDN) Gateway (PGW) 166. Although the foregoing elements are described as part of the CN 106, it will be appreciated that any of these elements may be owned and / or operated by entities other than the CN operator.

[0051] The MME 162 may be connected to each of eNode-Bs 162a, 162b, and 162c in the RAN 104 via the S1 interface and may act as a control node. For example, the MME 162 may be responsible for authenticating users of WTRUs 102a, 102b, and 102c, bearer activation / deactivation, selecting a particular serving gateway during the initial contact of WTRUs 102a, 102b, and 102c, etc. The MME 162 may provide control plane functions for handover between the RAN 104 and other RANs (not shown) employing other radio technologies such as GSM and / or WCDMA.

[0052] The SGW 164 may be connected to each of eNode Bs 160a, 160b, and 160c in the RAN 104 via the S1 interface. The SGW 164 may generally route and forward user data packets to and from the WTRUs 102a, 102b, and 102c. The SGW 164 may perform other functions such as anchoring the user plane during handover between eNode Bs, triggering paging when DL data is available for the WTRUs 102a, 102b, and 102c, managing and storing the context of the WTRUs 102a, 102b, and 102c, etc.

[0053] The SGW 164 may be connected to the PGW 166, which may provide the WTRUs 102a, 102b, and 102c with access to a packet switched network such as the Internet 110 to facilitate communication between the WTRUs 102a, 102b, and 102c and IP-enabled devices.

[0054] CN 106 can facilitate communication with other networks. For example, CN 106 can provide access to a circuit-switched network (such as the PSTN 108) to the WTRUs 102a, 102b, 102c to facilitate communication between the WTRUs 102a, 102b, 102c and traditional landline communication devices. For example, CN 106 can include an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that serves as an interface between CN 106 and the PSTN 108 or can communicate therewith. Additionally, CN 106 can provide access to other networks 112 to the WTRUs 102a, 102b, 102c, and the other networks can include other wired and / or wireless networks owned and / or operated by other service providers.

[0055] Although the WTRU is depicted as a wireless terminal in Figures 1A to 1D it is envisioned that in some representative embodiments, such a terminal can (e.g., temporarily or permanently) use a wired communication interface that utilizes a communication network.

[0056] In a representative embodiment, the other network 112 can be a WLAN.

[0057] A WLAN in infrastructure basic service set (BSS) mode can have an access point (AP) for the BSS and one or more stations (STAs) associated with the AP. The AP can have access to or an interface to a distribution system (DS) or another type of wired / wireless network that loads and / or unloads traffic to / from the BSS. Traffic going to an STA from outside the BSS can reach the STA through the AP and can be delivered to the STA. Traffic originating from an STA to a destination outside the BSS can be sent to the AP for delivery to the corresponding destination. Traffic between STAs within the BSS can be sent through the AP, e.g., where the source STA can send traffic to the AP and the AP can deliver the traffic to the destination STA. Traffic between STAs within the BSS can be considered and / or referred to as peer-to-peer traffic. Peer-to-peer traffic can be sent between the source STA and the destination STA using direct link setup (DLS) (e.g., sent directly between them). In some representative embodiments, the DLS can use 802.11e DLS or 802.11z tunnel DLS (TDLS). A WLAN using independent BSS (IBSS) mode may not have an AP, and STAs within the IBSS or using the IBSS (e.g., all STAs) can communicate directly with each other. The IBSS communication mode can sometimes be referred to in this document as an "ad hoc" communication mode.

[0058] When operating in 802.11ac infrastructure mode or a similar operating mode, the AP can transmit beacons on a fixed channel, such as the primary channel. The primary channel can be of a fixed width (e.g., a bandwidth of 20 MHz wide) or dynamically set width. The primary channel can be the operating channel of the BSS and can be used by the STA to establish a connection with the AP. In some representative embodiments, Carrier Sense Multiple Access with Collision Avoidance (CSMA / CA) can be implemented, for example, in an 802.11 system. For CSMA / CA, STAs including the AP (e.g., each STA) can sense the primary channel. If a particular STA senses / detects the primary signal and / or determines the primary signal to be busy, the particular STA can back off. One STA (e.g., only one station) can transmit in a given BSS at any given time.

[0059] High Throughput (HT) STAs can communicate using a 40 MHz wide channel, for example, by combining the primary 20 MHz channel with an adjacent or non - adjacent 20 MHz channel to form a 40 MHz wide channel.

[0060] Very High Throughput (VHT) STAs can support channels that are 20 MHz, 40 MHz, 80 MHz, and / or 160 MHz wide. 40 MHz and / or 80 MHz channels can be formed by combining consecutive 20 MHz channels. A 160 MHz channel can be formed by combining eight consecutive 20 MHz channels or by combining two non - consecutive 80 MHz channels, which can be referred to as an 80 + 80 configuration. For the 80 + 80 configuration, after channel coding, the data can be passed through a fragment parser, which can divide the data into two streams. Inverse Fast Fourier Transform (IFFT) processing and time - domain processing can be performed on each stream separately. The streams can be mapped to two 80 MHz channels, and the data can be transmitted by the transmitting STA. At the receiver of the receiving STA, the above operations for the 80 + 80 configuration can be reversed, and the combined data can be sent to the Media Access Control (MAC).

[0061] 802.11af and 802.11ah support operation modes below 1 GHz. The channel operation bandwidth and carrier are reduced in 802.11af and 802.11ah as compared to those used in 802.11n and 802.11ac. 802.11af supports 5 MHz, 10 MHz, and 20 MHz bandwidths in the TV white space (TVWS) spectrum, and 802.11ah supports 1 MHz, 2 MHz, 4 MHz, 8 MHz, and 16 MHz bandwidths using non-TVWS spectrum. According to a representative embodiment, 802.11ah may support meter type control / machine type communication (MTC), such as MTC devices in a macro coverage area. The MTC device may have certain capabilities, for example, limited capabilities, including supporting (e.g., only supporting) certain and / or limited bandwidths. The MTC device may include a battery with a battery life higher than a threshold (e.g., to maintain a very long battery life).

[0062] A WLAN system that can support multiple channels and channel bandwidths (such as 802.11n, 802.11ac, 802.11af, and 802.11ah) includes a channel that can be designated as a primary channel. The primary channel may have a bandwidth equal to the maximum common operation bandwidth supported by all STAs in the BSS. The bandwidth of the primary channel may be set and / or restricted by the STA that supports the minimum bandwidth operation mode among all STAs operating in the BSS. In an example of 802.11ah, for an STA that supports (e.g., only supports) the 1 MHz mode (e.g., an MTC type device), the primary channel may be 1 MHz wide, even if the AP and other STAs in the BSS support 2 MHz, 4 MHz, 8 MHz, 16 MHz, and / or other channel bandwidth operation modes. Carrier sensing and / or network allocation vector (NAV) setting may depend on the state of the primary channel. If the primary channel is busy, for example, due to an STA (which only supports the 1 MHz operation mode) transmitting to the AP, then all available bands may be considered busy even if most of the available bands remain idle.

[0063] In the United States, the available bands that can be used by 802.11ah are 902 MHz to 928 MHz. In Korea, the available bands are 917.5 MHz to 923.5 MHz. In Japan, the available bands are 916.5 MHz to 927.5 MHz. The total bandwidth available for 802.11ah is 6 MHz to 26 MHz, depending on the country code.

[0064] Figure 1Dis a system diagram showing RAN 104 and CN 106 according to an embodiment. As described above, RAN 104 may employ NR radio technology to communicate with WTRUs 102a, 102b, 102c via air interface 116. RAN 104 may also communicate with CN 106.

[0065] RAN 104 may include gNBs 180a, 180b, 180c, but it will be understood that RAN 104 may include any number of gNBs while remaining consistent with the embodiment. gNBs 180a, 180b, 180c may each include one or more transceivers for communicating with WTRUs 102a, 102b, 102c via air interface 116. In one embodiment, gNBs 180a, 180b, 180c may implement MIMO technology. For example, gNBs 180a, 180b may utilize beamforming to transmit signals to and / or receive signals from gNBs 180a, 180b, 180c. Thus, for example, gNB 180a may use multiple antennas to transmit wireless signals to and / or receive wireless signals from WTRU 102a. In one embodiment, gNBs 180a, 180b, 180c may implement carrier aggregation technology. For example, gNB 180a may transmit multiple component carriers to WTRU 102a (not shown). A subset of these component carriers may be located on unlicensed spectrum, while the remaining component carriers may be located on licensed spectrum. In one embodiment, gNBs 180a, 180b, 180c may implement coordinated multi-point (CoMP) technology. For example, WTRU 102a may receive coordinated transmissions from gNB 180a and gNB 180b (and / or gNB 180c).

[0066] WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using transmissions associated with a scalable digital architecture. For example, the OFDM symbol interval and / or the OFDM subcarrier interval may change for different transmissions, different cells, and / or different portions of the radio transmission spectrum. WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using subframes or transmission time intervals (TTIs) of various lengths or scalable lengths (e.g., containing different numbers of OFDM symbols and / or lasting for different lengths of absolute time).

[0067] gNBs 180a, 180b, 180c may be configured to communicate with WTRUs 102a, 102b, 102c in stand-alone configuration and / or non-stand-alone configuration. In stand-alone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c without also accessing another RAN (e.g., such as eNode Bs 160a, 160b, 160c). In stand-alone configuration, WTRUs 102a, 102b, 102c may use one or more of gNBs 180a, 180b, 180c as a mobility anchor. In stand-alone configuration, WTRUs 102a, 102b, 102c may communicate with gNBs 180a, 180b, 180c using signals in an unlicensed band. In non-stand-alone configuration, WTRUs 102a, 102b, 102c may communicate / connect with gNBs 180a, 180b, 180c while also communicating / connecting with another RAN (such as eNode-Bs 160a, 160b, 160c). For example, WTRUs 102a, 102b, 102c may implement the DC principle to communicate with one or more gNBs 180a, 180b, 180c and one or more eNode-Bs 160a, 160b, 160c substantially simultaneously. In non-stand-alone configuration, eNode-Bs 160a, 160b, 160c may serve as the mobility anchor for WTRUs 102a, 102b, 102c, and gNBs 180a, 180b, 180c may provide additional coverage and / or throughput to serve WTRUs 102a, 102b, 102c.

[0068] Each of gNBs 180a, 180b, 180c may be associated with a specific cell (not shown) and may be configured to handle radio access network resource management decisions, handover decisions, user scheduling in UL and / or DL, support for network slicing, DC, interworking between NR and E-UTRA, routing of user plane data towards user plane functions (UPFs) 184a, 184b, routing of control plane information towards access and mobility management functions (AMFs) 182a, 182b, etc. As Figure 1D shown, gNBs 180a, 180b, 180c may communicate with each other via the Xn interface.

[0069] Figure 1DThe illustrated CN 106 may include at least one AMF 182a, 182b, at least one UPF 184a, 184b, at least one session management function (SMF) 183a, 183b, and possibly data networks (DN) 185a, 185b. Although the foregoing elements are described as part of CN 106, it will be appreciated that any of these elements may be owned and / or operated by an entity other than the CN operator.

[0070] The AMF 182a, 182b may be connected via an N2 interface to one or more of the gNBs 180a, 180b, 180c in the RAN 104 and may act as a control node. For example, the AMF 182a, 182b may be responsible for authenticating users of the WTRUs 102a, 102b, 102c, supporting network slicing (e.g., handling different protocol data unit (PDU) sessions with different requirements), selecting a particular SMF 183a, 183b, managing the registration area, terminating non-access stratum (NAS) signaling, mobility management, etc. The AMF 182a, 182b may use network slicing in order to customize the CN support for the WTRUs 102a, 102b, 102c based on the type of service that the WTRUs 102a, 102b, 102c are utilizing. For example, different network slices may be established for different use cases, such as services that rely on ultra-reliable low-latency (URLLC) access, services that rely on enhanced massive mobile broadband (eMBB) access, services for machine type communication (MTC) access, etc. The AMF 182a, 182b may provide control plane functions for handovers between the RAN 104 and other RANs (not shown) that employ other radio technologies (such as LTE, LTE-A, LTE-A Pro) and / or non-3GPP access technologies (such as WiFi).

[0071] The SMF 183a, 183b may be connected via an N11 interface to the AMF 182a, 182b in the CN 106. The SMF 183a, 183b may also be connected via an N4 interface to the UPF 184a, 184b in the CN 106. The SMF 183a, 183b may select and control the UPF 184a, 184b and configure the routing of traffic through the UPF 184a, 184b. The SMF 183a, 183b may perform other functions, such as managing and allocating WTRU IP addresses, managing PDU sessions, controlling policy enforcement and QoS, providing DL data notifications, etc. The PDU session type may be IP-based, non-IP-based, Ethernet-based, etc.

[0072] UPF 184a and 184b can be connected via the N3 interface to one or more of gNBs 180a, 180b, 180c in RAN 104, which can provide the WTRUs 102a, 102b, 102c with access to a packet switched network such as the Internet 110 to facilitate communication between the WTRUs 102a, 102b, 102c and IP-enabled devices. UPF 184, 184b can perform other functions such as routing and forwarding packets, enforcing user plane policies, supporting multi-homed PDU sessions, handling user plane QoS, buffering DL packets, providing mobile anchoring, etc.

[0073] CN 106 can facilitate communication with other networks. For example, CN 106 can include an IP gateway (e.g., an IP Multimedia Subsystem (IMS) server) that is an interface between CN 106 and the PSTN 108 or can communicate with the IP gateway. Additionally, CN 106 can provide the WTRUs 102a, 102b, 102c with access to other networks 112, which can include other wired and / or wireless networks owned and / or operated by other service providers. In one embodiment, the WTRUs 102a, 102b, 102c can be connected to DNs 185a, 185b via UPF 184a, 184b through the N3 interface to UPF 184a, 184b and the N6 interface between UPF 184a, 184b and local DNs 185a, 185b.

[0074] In view of Figures 1A to 1D and Figures 1A to 1D the corresponding descriptions, one or more of the functions described herein with respect to one or more or all of the following can be performed by one or more emulation devices (not shown): WTRUs 102a to 102d, base stations 114a to 114b, eNode-Bs 160a to 160c, MME 162, SGW 164, PGW 166, gNBs 180a to 180c, AMFs 182a to 182b, UPFs 184a to 184b, SMFs 183a to 183b, DNs 185a to 185b, and / or any other device described herein. The emulation device(s) can be one or more devices configured to emulate one or more or all of the functions described herein. For example, the emulation device(s) can be used to test other devices and / or simulate network and / or WTRU functionality.

[0075] The simulation device can be designed to implement one or more tests on other devices in a laboratory environment and / or an operator network environment. For example, one or more simulation devices can perform one or more or all functions when fully or partially implemented and / or deployed as part of a wired and / or wireless communication network to test other devices within the communication network. One or more simulation devices can perform one or more or all functions when temporarily implemented / deployed as part of a wired and / or wireless communication network. The simulation device can be directly connected to another device for testing purposes and / or perform tests using over-the-air wireless communication.

[0076] One or more simulation devices can perform one or more (including all) functions when not implemented / deployed as part of a wired and / or wireless communication network. For example, the simulation device can be used in a test laboratory and / or a test scenario in a non-deployed (e.g., test) wired and / or wireless communication network to implement tests on one or more components. One or more simulation devices can be test equipment. The simulation device can transmit and / or receive data using a direct RF connection and / or wireless communication via an RF circuit (e.g., which can include one or more antennas).

[0077] Channel state information (CSI) can include at least one of the following: channel quality index (CQI), rank indicator (RI), precoding matrix index (PMI), L1 channel measurements (e.g., RSRP, such as L1-RSRP or SINR), CSI-RS resource indicator (CRI), SS / PBCH block resource indicator (SSBRI), layer indicator (LI), and / or any other measurement quantity measured by the WTRU from the configured CSI-RS or SS / PBCH block.

[0078] Uplink control information (UCI) can include: CSI, HARQ feedback for one or more HARQ processes, scheduling request (SR), link recovery request (LRR), CG-UCI, and / or other control information bits that can be transmitted on the PUCCH or PUSCH.

[0079] Channel conditions can be any conditions related to the state of the radio / channel, which can be determined by the WTRU based on the following information: WTRU measurements (e.g., L1 / SINR / RSRP, CQI / MCS, channel occupancy, RSSI, power headroom, exposure headroom), L3 / mobility-based measurements (e.g., RSRP, RSRQ, s-measurement), RLM state, and / or channel availability in unlicensed spectrum (e.g., determining whether the channel is occupied based on the determination of the LBT procedure, or whether the channel is considered to have experienced a consistent LBT failure).

[0080] The PRACH resources include PRACH resources (e.g., in terms of frequency), PRACH occasion (RO) (e.g., in terms of time), preamble format (e.g., in terms of total preamble duration, sequence length, guard time duration, and / or length of cyclic prefix), and / or a specific preamble sequence used to transmit the preamble during the random access procedure.

[0081] The attributes of scheduling information (e.g., uplink grant or downlink allocation) may include one or more of the following: frequency allocation; aspects of time allocation such as duration; priority; modulation and coding scheme; transport block size; number of spatial layers; number of transport blocks to be carried; TCI state or SRI; number of repetitions; and whether the grant is configured grant type 1, type 2, or dynamic grant.

[0082] The indication or indication by DCI may include one or more of the following: an explicit indication of a DCI field or an RNTI used to mask the CRC of the PDCCH; an implicit indication of attributes such as DCI format, DCI size, core set or search space, aggregation level, identification of the first control channel resource of the DCI (e.g., index of the first CCE), where the mapping between the attribute and the value may be signaled by RRC or MAC; and an explicit indication by DL MAC CE.

[0083] The terms network availability state and NES state may be used interchangeably.

[0084] NR system information (SI) includes the MIB (master information block) and multiple SIBs (system information blocks). The SIBs are divided into minimum SI and other SI. The minimum SI carries the information required for initial access and for obtaining any other SI. The minimum SI consists of the MIB and SIB1. In order for a WTRU to be allowed to camp on a cell, it must have obtained the content of the minimum SI of that cell. Other SI includes SIBs not broadcast in the minimum SI. The WTRU does not need to receive these SIBs before accessing the cell. Other SI is also referred to as on-demand SI because the gNB may only transmit / broadcast these SIBs when explicitly requested by the WTRU. This is for the purpose of saving network energy.

[0085] The MIB may contain cell barred status information and the basic physical layer information of the cell required to receive further system information, such as the CORESET#0 configuration. The MIB is broadcast periodically on the BCH (with a period of 80 ms, and within 80 ms, repeated transmissions may occur).

[0086] SIB1 can define the scheduling of other system information blocks and contains information required for initial access. SIB1 is also referred to as the Remaining Minimum SI (RMSI) and is broadcast periodically on the DL-SCH or sent to the WTRU in a dedicated manner on the DL-SCH in RRC_CONNECTED.

[0087] Figure 2 Shows the time-frequency structure of the Synchronization Signal Block (SSB) 200. The SSB 200 occupies 240 subcarriers 210 in the frequency domain and 4 symbols 220 in the time domain. The SSB 200 includes a Primary Synchronization Signal (PSS) 230, a Secondary Synchronization Signal (SSS) 240, and a Physical Broadcast Channel (PBCH) 250. The PSS 230 and the SSS 240 each occupy 1 symbol and 127 subcarriers. The PBCH 250 can span 3 OFDM symbols and 240 subcarriers. As Figure 2 shown, one of the symbols in the middle of the PBCH 250 can be not used for the SSS 240. The PSS 230 and the SSS 240 can provide the Physical Cell Identity (PCI), and the PBCH 250 can carry the Master Information Block (MIB) plus additional payload bits.

[0088] The possible time positions of the SSB 200 within a half-frame are determined by the subcarrier spacing, and the periodicity of the half-frame in which the SSB 200 is transmitted is configured by the network. During a half-frame, different SSB 200 can be transmitted in different spatial directions (i.e., using different beams, across the coverage area of the cell). Multiple SSB 200 can be transmitted within the frequency span of a carrier. The PCI of the SSB 200 transmitted at different frequency positions does not have to be unique, i.e., different SSB 200 in the frequency domain can have different PCI. However, when an SSB is associated with the RMSI, the SSB is referred to as a Cell-Defining SSB (CD-SSB). The PCell is always associated with a CD-SSB located on the synchronization raster.

[0089] The WTRU can assume the band-specific subcarrier spacing of the SSB 200 unless the network has configured the WTRU to assume a different subcarrier spacing. Multiple beams can be associated with a given beam, and multiple SSB 200 can be transmitted on different beams within a given cell (i.e., beam scanning).

[0090] Figure 3 An example of beam scanning 300. The periodically broadcast SSB 310 can be transmitted periodically from each cell. The SSB can be organized into burst sets, each burst set including one or more SSB. The number of SSB can be configured such that, for example, 64 can be used for higher frequencies. Each SSB has an index 325 that increases from 0 to the number of SSB minus 1. The periodicity 315 is inFigure 3 It is shown as 10 ms in the figure. The range of this periodicity 315 can be from 5 ms to 160 ms.

[0091] Figure 3 Via beam scanning 300, a plurality of SSBs 320 (8 SSB-indices 325 from 0 to 7) are transmitted at intervals. Each SSB can be identified by the SSB index 325, where each SSB is transmitted via a specific beam radiated in a specific direction. A plurality of WTRUs (shown as WTRU 334 and WTRU 336) are located at various positions around the gNB 330. Each WTRU 334, 336 measures the signal strength of each SSB it detects within a certain time period (the time period of one SSB set). Based on the measurement results, each WTRU 334, 336 can use the measured signal strength map 340 to identify the SSB index with the strongest signal strength. For example, as Figure 3 further shown in the figure, beam #1 342 is the best beam (the selected beam) for WTRU 1 334, and beam #7 344 is the best beam for WTRU 2 336.

[0092] The number of different beams transmitted can be determined by the number of SSBs transmitted within an SSB burst set (a set of SSBs transmitted in a 5 ms SSB transmission window). For example, in FR1, the maximum number of SSBs within an SSB set is 4 or 8, while for FR2, it can be 64.

[0093] A network availability state / NES state may exist. A WTRU may determine whether it can transmit or receive on certain resources based on the network availability state (which implies the power saving state of the gNB). The availability state may correspond to a network energy saving state or a gNB activity level. The availability state may be uplink or downlink specific and may change between symbols, between time slots, between frames, or at a longer duration granularity. The availability state may be determined by the WTRU or indicated by the network. The availability state may be, for example, "on", "DL and UL active", "UL only active", "off", "reduced Tx power", "sleep", "micro-sleep", "light sleep", or "deep sleep". Such states may be abstracted by NW configuration parameters and / or values, and the dynamic indication may point to the active availability state (e.g., via DCI or MAC CE signaling). The "off" availability state may mean that the baseband hardware of the gNB has been completely turned off. The "sleep" availability state may mean that the gNB wakes up periodically to transmit certain signals (e.g., presence signals, synchronization or reference signals) or receive certain UL signals. In certain availability states, certain DL or UL resources are unavailable for certain periods of time, and this enables the network to turn off baseband processing and other activities. Certain measurement resources (e.g., SSB or CSI-RS) may be available only in certain available states, including: RLM, BFD, RRM measurements, CSI-RS feedback configuration, and / or different power offsets for CSI feedback.

[0094] Under certain conditions, the WTRU may also transmit a request (wake-up request) to the network to modify the availability state to a state where resources that will satisfy the WTRU requirements are available. Such a wake-up request may include a transmission that can be decoded by a low complexity receiver at the gNB, for which the energy consumption requirement is minimal. The wake-up request, turn-on request, or WTRU assistance information for wake-up may be used interchangeably. In certain availability states (e.g., "micro-sleep" or "deep sleep"), the wake-up request may be specifically used and may refer to a physical uplink signal transmitted by the WTRU to request a change in the availability state. The physical layer design of the wake-up request signal is detailed below. The turn-on request may also be a physical layer or L2 indication from the WTRU to the network, which may be conveyed as MAC CE, UCI, RRC signaling, or RRC reconfiguration signaling (e.g., applicable to NES-, PUCCH, or RACH indication), and may include WTRU assistance information for wake-up and / or a positioning report.

[0095] The WTRU may determine the availability state based on an availability state indication received from, for example, L1 / L2 signaling (e.g., group common DCI or indication), or may implicitly determine the availability state based on received periodic DL signaling (or the lack thereof).

[0096] If a resource is applicable in an active availability state, the WTRU may determine whether the resource is available for transmission / reception and / or measurement for the determined network availability state. Additionally, the WTRU may also adjust its active C-DRX cycle, active spatial elements (such as antennas or logical ports), active TRP, and paging occasion according to the signaled or determined NES state. The WTRU may be configured with one or more sets of NES transmission and / or reception parameters for each NES state, for example, via broadcast or dedicated configuration signaling. The WTRU may apply the NES parameter set according to the determined or signaled NES state. The WTRU may apply one or more applicable configurations according to the determined NES state. A set of NES parameters may include one or more of the following: the number of antenna ports, C-DRX configuration, measurement configuration (e.g., for RRM, RLM, and / or BFD), CSI feedback, CSI-RS configuration, SSB configuration, CHO or mobility candidate, a set of active TRP.

[0097] The availability state may apply to at least one transmission, reception, or measurement resource. The availability state may apply to at least one time period, such as a time slot or time symbol. The availability state may apply to a serving cell, cell group, frequency band, bandwidth part, TRP, a set of spatial elements, or a frequency range within a bandwidth part. For example, when the NES state changes in a cell, the WTRU may receive an availability state change indication that indicates that this change is only for that cell, for all cells of the same frequency or / and the same RAT.

[0098] After receiving DL signaling that changes the availability state of a cell or TRP, the WTRU may consider the active availability state associated with the cell, carrier, TRP, or frequency band as "off", "deep sleep", or "micro sleep". For example, the WTRU may receive a shutdown command on broadcast signaling, RRC signaling, DCI (e.g., group common DCI), or DL MAC CE (e.g., the indication part of PDSCH). The WTRU may determine the availability state from an availability state indication received, for example, via L1 / L2 signaling (e.g., group common DCI or indication).

[0099] For example, the WTRU may determine a change in the NES state change from receiving group common command L1 signaling (e.g., group common DCI, multi-level DCI, specific DCI format, or DCI scrambled by a configured or designated NES-specific RNTI). The L1 signaling may indicate one of the configured NES parameter sets to be applied, or may determine an incremental configuration from the current parameter set after determining the NES state change. After receiving the NES state change indication, the WTRU may transmit feedback / acknowledgment to the gNB, possibly multiplexed with UL data (e.g., as part of a MAC CE or sub-header indication of the UL TB).

[0100] In addition, for example, the WTRU may determine a change in the NES state change based on receiving broadcast signaling associated with the NES state indication or change, including signaling in the SIB, or a part of the broadcast or multicast PDSCH. The WTRU may explicitly indicate the NES state in the SIB. The WTRU may be configured with one or more SIBs specifically associated with the configuration of NES parameters. The WTRU may be configured to receive such broadcast or multicast indications periodically; if the indication is not received at the expected periodic timing, if a certain number of error detections are counted, and / or if a timer has expired since the last reception of the NES state indication, the WTRU may determine that the indication has been misdetected. After determining the misdetection of the NES state indication, the WTRU may initiate inter-cell, inter-frequency, and / or inter-RAT measurements, initiate a mobility procedure, and / or start evaluating the configured CHO candidates.

[0101] The WTRU may implicitly assume certain availability states (e.g., "off", "deep sleep", "microsleep", or dormant") associated with a cell, carrier, TRP, or frequency band from at least one of the following.

[0102] The WTRU may assume certain availability states based on receiving a command or signal indicating a change in the availability state (e.g., group common DCI or RRC signaling or a presence signal in the connected mode). The WTRU may implicitly determine the availability state based on receiving periodic DL signaling. The WTRU may be configured or designated to associate the availability state with one or more DL signal types (e.g., SSB, partial SSB, and / or one or more periodicities).

[0103] The WTRU may assume certain availability states based on receiving a paging message, paging DCI, paging PDSCH, or paging-related signal (e.g., PEI) that may be in a subset of the POs (e.g., those consistent with the NES drx period or a configured subset of PDCCH resources). The WTRU may assume certain availability states after receiving an indication portion of DCI or PDCCH scheduling paging (e.g., according to a P-RNTI, NES-RNTI, or based on an explicit indication received, for example, on a reserved bit). The WTRU may assume certain availability states after receiving a paging message with a specific P-RNTI, separately configured NESP-RNTI, or NES group RNTI. The WTRU may assume a specific available state after receiving a paging message with a specific P-RNTI. The WTRU may be configured with another subgroup of PEIs for the NES, where the subgroup may be associated with one or more availability states. The WTRU may assume certain availability states after receiving a PEI with an NES subgroup, possibly if the subgroup has been configured with an availability state and / or is associated with the availability state. An indication of an availability state or an availability state transition may be indicated in the paging payload, for example, as a flag portion of the paging message or short message. Such paging indication may also indicate that a secondary cell monitors paging when the cell receiving the signaling is closed, in sleep, or in the NES state. Such paging indication may also indicate or signal applicable reconfiguration parameters (e.g., for initial access, applicable PRACH resources, applicable SSB / RS occasions, applicable SI periods, and / or applicable cells and associated availability states).

[0104] The WTRU may assume a specific availability state based on the gNB DTX state (regardless of whether the gNB is in active time or whether the associated active timer is running).

[0105] The WTRU may assume certain availability states due to the non-detection of a presence indication, including the WTRU determining the availability state associated with a cell (e.g., "off" or "deep sleep") if the presence indication is not detected during one or more presence indication occasions. The WTRU may assume or change the availability state of the cell after consecutive incorrect detections or after the expiration of a timer after the non-detection of a presence signal. The WTRU may determine whether the availability state is active or inactive after the expiration of a timer associated with the availability state. Such timers may be configured and / or maintained only in the connected mode or may also be configured and / or maintained in other states (e.g., idle and inactive states). The WTRU may implicitly determine the availability state based on the non-receipt of periodic DL signaling. For example, the WTRU may be configured with a signal quality threshold (e.g., an RSRP threshold), and if the WTRU does not detect a signal (e.g., a presence signal or an SSB) associated with the availability state whose signal strength is above the threshold, the WTRU may assume that the availability state is inactive and may assume a different availability state. The criterion may also be combined with the identification sequence of the non-detection of a presence signal (e.g., the detection of a PSS sequence).

[0106] The WTRU may assume certain availability states based on the time of day. For example, the WTRU may be configured to automatically assume certain availability states (e.g., off, sleep, or dormant) of a configured subset of cells (e.g., capacity-boost cells) according to the time of day. For example, the WTRU may determine that the availability state of a capacity-boost cell is "on" during certain periods of the day, "deep sleep" during other configured periods, and "off" during a third set of configured periods during the day or night.

[0107] The WTRU may assume certain availability states based on the availability state of an associated cell (e.g., another carrier of the same MAC entity, another carrier in the same cell group, another carrier in the same gNB, another sector in the same gNB, or a configured associated cell or capacity-boost cell).

[0108] The WTRU may assume certain availability states based on the detection of only a PSS signal or a simplified / trimmed SSB signal.

[0109] The WTRU may assume certain availability states based on the detection of an RS signal (e.g., CSI-RS, PRS, TRS) or the lack of an RS signal.

[0110] The WTRU may assume certain availability states based on the RRC state (idle, inactive, or connected mode) of the WTRU.

[0111] The WTRU may assume certain availability states based on whether paging has been received (possibly within a configured time window).

[0112] The WTRU may assume certain availability states based on whether system information has been received (e.g., a subset of periodic SI or SIBs) (possibly within a configured time window).

[0113] The WTRU may assume certain availability states based on measured channel conditions being below or above a threshold. The WTRU may assume a change in the NES state based on a change in the measured channel conditions or causing the channel measurement to be below or above the threshold. For example, the WTRU may use the measured degradation of an SSB or CSI-RS (possibly in combination with other signaling) to determine the NES state. For example, a configured window after DCI reception may be used to measure the degradation of the SSB and / or CSI-RS, and if an incremental decrease in SSB-RSRP is measured, the WTRU may determine that the NES state has changed and take an action associated with such NES state (e.g., trigger CHO candidate selection or trigger group scheduling of a mobility command).

[0114] The WTRU may be configured to monitor an indication that may characterize the network activity level (e.g., availability state). The network activity may be associated with a gNB and / or a cell. The WTRU may assume the same availability state for all cell parts of the same gNB (e.g., cells of the same MAC entity). The network activity indication (e.g., a presence indication) may include a channel (e.g., PDCCH) and / or a signal (e.g., a sequence). The activity indication or NES state change indication / command may indicate the activity level that the WTRU may expect from the associated gNB and / or cell, e.g., reduced activity. The activity indication may contain activity information of other gNBs / cells. The activity indication may be a PDCCH containing group common signaling. For example, the NW may transmit group common DCI to a group of WTRUs (e.g., WTRUs in a serving cell) that indicates a change in the activity state or activity level in the UL and / or DL. The CRC of the PDCCH may be scrambled with a dedicated "activity indication RNTI or NES-RNTI". The WTRU may be configured with at least one search space associated with the monitoring occasion of the activity indication PDCCH. The indication may consist of a sleep signal, e.g., a predefined sequence. When the WTRU detects this sequence, the WTRU may expect a reduction in the activity level within a specific duration. The WTRU may activate C-DRX within the indicated time period. Alternatively, two sequences may be used to indicate normal activity and reduced activity.

[0115] The signaling or activity indication within the PDCCH may include at least one of the following.

[0116] The signaling or activity indication within the PDCCH may include the expected activity level (e.g., availability status) of the gNB / cell associated over a particular time interval. The activity level may be predefined and / or configured and may consist of, for example, regular activity and reduced activity. The signaling may indicate the activity level. For example, a bit “1” may indicate regular activity and a bit “0” may indicate reduced activity.

[0117] The signaling or activity indication within the PDCCH may include that, for each activity level (e.g., availability status), transmit and receive attributes may be defined. For example, during reduced activity, the WTRU may not be expected to monitor certain PDCCH search spaces (including all SSs), and / or receive certain types of PDSCHs (including all PDSCHs), and / or transmit PUCCH / PUSCH, and / or perform certain measurements. The WTRU may start or stop monitoring PDCCHs and / or TCI states associated with a determined NES state, including PDCCH resources or TCI states associated with (de)activated TRPs or spatial elements.

[0118] The signaling or activity indication within the PDCCH may include a set of configurations that may be associated with the activity level and may be used / applied when indicating that activity level (e.g., NES parameter set). For example, SS configuration, CSI report configuration, index of transmitted SSBs, etc. Each set of configurations may have attributes associated with the activity level. For example, a label that may be set to “reduced activity”.

[0119] The signaling or activity indication within the PDCCH may include the time interval assuming the activity level, which may be signaled in the PDCCH or be part of the activity indication. A bitmap may be used to indicate the time interval, where each bit in the bitmap may be associated with a particular duration, e.g., a time slot or a frame. For example, a bit “1” may indicate regular activity and a bit “0” may indicate reduced activity on the associated frame. The time interval may be indicated with a start time and an interval length. The start time may be defined; for example, it may be determined by adding a fixed offset to the time when the indication is received. The length of the interval may be configured or signaled in the indicating PDCCH.

[0120] The signaling or activity indication within the PDCCH may include the time interval that may pre - determine the assumed activity level. The WTRU may assume an interruption delay (or more generally, the time until the NES state change) after receiving an NES state change command (e.g., after the last symbol or time slot of the command). The interruption time may be an absolute time, a number of symbols, or a number of time slots.

[0121] The WTRU may perform mobility to another serving cell, trigger mobility-related measurements, and / or start evaluating CHO candidates on a secondary cell after determining a NES change. The WTRU may be configured or pre-defined with secondary serving cells to perform initial access, mobility, or cell reselection in the event that the current serving cell or capacity-boosting cell is shut down or meets specific conditions. The WTRU may be configured with a list of fallback or secondary serving cells based on broadcast or dedicated signaling, possibly for each serving cell or each gNB. For example, the WTRU may initiate a cell reselection or mobility procedure for a secondary serving cell associated with a cell or gNB that has received a shutdown indication. In one example, an indication to shut down or enter sleep may be dynamically indicated to the WTRU via, for example, dedicated or broadcast signaling as to which cell to fallback to or connect to. The fallback / secondary cell may be configured or pre-defined as a cell within the same gNB where the sector has entered the NES state (e.g., shutdown, sleep, or reduced power). In another example, if the WTRU is in dual connectivity, the fallback cell may be pre-defined as the primary node cell. The fallback / secondary cell may be configured or pre-defined as a cell associated with a different RAT or frequency band. For example, the WTRU may fallback to an LTE or FR1 cell associated with the cell or gNB from which it received the shutdown indication (e.g., if the WTRU is in CA or DC using multiple RATs or multiple frequency bands).

[0122] If uplink or downlink resources or signals are applicable in an active availability state, the WTRU may determine whether the uplink or downlink resources or signals are available for transmission / reception and / or perform measurements for the determined network availability state. The WTRU may determine that a subset of measurement resources and / or signals (e.g., SSB, CSI-RS, TRS, PRS) are not applicable in certain availability states. The WTRU may determine that a subset of uplink or downlink resources (e.g., PRACH, PUSCH, PUCCH) are not applicable in certain availability states. The WTRU may transmit some uplink signals only within a subset of NW availability states (e.g., SRS, pSRS, PRACH, UCI).

[0123] A NES WTRU group can be provided. The WTRUs can be grouped for NES purposes, such as to control multiple WTRUs simultaneously, such as to indicate bwp switching, indicate a change in NW availability status, indicate a change in WTRU DRX cycle / parameters, for mobility / cell reselection, paging, and / or activation / deactivation of DL measurement resources. For this purpose, the WTRUs can be configured with a NES group RNTI (more generally, a NES group identifier), which can be used to signal to one or more WTRUs in the same serving cell. The WTRUs can monitor cell-specific DL resources to receive control and / or data, to receive group-common indications of the NES (e.g., group-common DCI, availability status switching command, NES PCell switching command).

[0124] The WTRU can monitor the reception of the presence of an indication or signal (such as a cell presence indication) associated with a gNB configured with one or more availability states (e.g., on, off, sleep, and / or deep sleep). The presence indication can be a physical downlink signal transmitted by an associated cell or gNB that is sleeping, e.g., may be in some availability states (e.g., deep sleep, micro-sleep, sleep, or off). Alternatively, the presence indication can be downlink information bits transmitted to the WTRU, e.g., via broadcast signaling (e.g., SIB) or via dedicated signaling (e.g., RRC signaling or MAC CE).

[0125] The WTRU can change to an availability state associated with detecting a presence signal (e.g., the WTRU assumes "on") after it successfully receives a response to the transmitted WTRU assistance information or wake-up request from the requested cell, where the response can be the reception of a DL signal or channel (e.g., SSB, CSI-RS, PRS, PDCCH, DCI, PDSCH, HARQ-ACK) or an L2 message (e.g., RRC message, DL MAC CE, Msg2, MsgB, or Msg4). The WTRU can start monitoring additional TRP, SSB, and / or CSI-RS resources after transmitting the wake-up WTRU assistance information or wake-up request or successfully receiving a response thereto. After successfully measuring that the channel conditions (e.g., RSRP, SINR) on the measurement resources of the associated cell are higher than a configured threshold, the WTRU can change to an availability state associated with detecting a presence signal (e.g., on).

[0126] The presence indication signal may be at least one of the following: a simplified or reduced SSB signal, such as PSS / SSS without PBCH multiplexing, a wide beam or omnidirectional SSB, PRS, CSI-RS, a signal detected based on energy sensing ether (e.g., a DL signal associated with a wake-up radio if the WTRU is capable of having the hardware to detect it), PDSCH or PDCCH received on different cells or TRPs (possibly on a subset of configured resources, a core set, or a search space), and / or one or more SSBs received on different cells or TRPs (possibly configured on a subset of SSB occasions).

[0127] NR includes the concepts of conditional handover (CHO) and conditional PSCell addition / change (CPA / CPC, or collectively CPAC), the main purpose of which is to reduce the likelihood of radio link failure (RLF) and handover failure (HOF). Traditional LTE / NR handovers are typically triggered by measurement reports, even though nothing prevents the network from sending a HO command to the WTRU without receiving a measurement report. For example, in the case of dual connectivity (DC), the WTRU is configured with an A3 event, which triggers a measurement report to be sent when the radio signal level / quality (RSRP, RSRQ, etc.) of an adjacent cell becomes better than that of the primary serving cell (PCell) or the primary-secondary serving cell (PSCell) as well. The WTRU monitors the serving cell and adjacent cells and can send a measurement report when the conditions are met. When such a report is received, the network (the current serving node / cell) can prepare a HO command (basically an RRC reconfiguration message with reconfigurationWithSync) and send it to the WTRU, and the WTRU immediately executes the command, resulting in the WTRU connecting to the target cell.

[0128] CHO differs from traditional handovers in two main aspects. First, multiple handover targets are prepared (in contrast, there is only one target in the traditional case), and second, the WTRU does not immediately execute the CHO as in traditional handovers. Instead, the WTRU is configured with trigger conditions (a set of radio conditions), and the WTRU will only execute a handover to one of the targets if and only if the trigger conditions are met.

[0129] When the radio conditions for the current serving cell are still good, a CHO command can be sent, thus reducing the two main failure points in traditional handovers, namely the risk of not being able to send a measurement report (e.g., if the link quality of the current serving cell deteriorates below an acceptable level when triggering a measurement report in a normal handover) and the risk of not being able to receive a handover command (e.g., if the link quality of the current serving cell deteriorates below an acceptable level after the WTRU has sent a measurement report but before it receives a HO command).

[0130] The triggering conditions for CHO can also be based on the radio quality of the serving cell and neighboring cells, similar to the conditions used to trigger measurement reports in traditional NR / LTE. For example, a WTRU can be configured with a CHO having A3 class triggering conditions and associated HO commands. The WTRU monitors the current and serving cells, and when the A3 triggering condition is met, it can execute the associated HO command and switch its connection to the target cell instead of sending a measurement report.

[0131] Figure 4 A signaling diagram 400 showing conditional handover configuration and execution. The signaling diagram includes a WTRU 405 in communication, a source node 415, and a potential target node 425. At 402, the source node 415 can signal a CHO request at the potential target node 425. At 404, the potential target node 425 provides a CHO request confirmation to the source node 415 at 404. In some examples, this CHO request confirmation can be an RRCReconfioguiration message. At 406, the source node 415 signals a CHO configuration to the WTRU 405. The CHO configuration can include the conditions for triggering the CHO. For example, the condition can be an A3 / A5 event and can also include an RRCReconfiguration message.

[0132] At 410, the WTRU 405 can monitor the CHO conditions provided in message 406 for one or more target cell candidates. If the conditions are met, then at 4210, the WTRU 405 performs a HO to the target cell for which the conditions are met. At 412, the WTRU 405 sends a CHO confirmation to the potential target node 425. At 430, the potential target node 426 performs a path switch and WTRU context release.

[0133] CHO can help prevent unnecessary reconstructions in the case of radio link failures. For example, assume that a WTRU is configured with multiple CHO targets and the WTRU experiences an RLF before the triggering conditions for any of the targets are met. Traditional operation would result in an RRC reconstruction process, which would cause a significant interruption time for the bearers of the WTRU. However, in the case of CHO, if the WTRU, after detecting an RLF, eventually reaches a cell with which it has a CHO association (i.e., the target cell is ready for this), the WTRU will directly execute the HO command associated with that target cell instead of proceeding with a full reconstruction process.

[0134] CPC and CPA are just extensions of CHO, but in the DC scenario. A WTRU can be configured with triggering conditions for PSCell change or addition, and when the triggering conditions are met, it can execute the associated PSCell change or PSCell addition command.

[0135] For a WTRU 405 that performs monitoring 410, measurement and event configurations for handover and conditional handover can be provided. Some IEs (information elements) of the measurement configuration that can be provided to the WTRU are shown below.

[0136]

[0137]

[0138] The main components of the measurement configuration include measurement objects, reporting configuration, measurement ID configuration, S-measurement configuration, quantity configuration, and measurement gap configuration.

[0139] The measurement object specifies what the WTRU 405 must measure and some information about how to perform the measurement. This includes information such as: RAT, frequency, subcarrier spacing, SSB periodicity / offset / duration, reference signals and signal types to be measured, list of allowed / excluded neighboring cells of the relevant RAT / frequency to be measured, measurement gap (timing and duration), offsets that can be used to prioritize / deprioritize certain cells, etc. The WTRU 405 can be configured with multiple measurement objects, and the WTRU 405 can have measurement configurations that can be related to different frequencies and even different RATs. The WTRU 405 can be configured with up to 64 measurement objects, and each measurement object is identified by a measurement object ID.

[0140] The reporting configuration specifies what to report (e.g., reference signal type, such as CSI-RS or SSB, number of beam and cell levels to report, such as RSRP / RSRQ, maximum number of cells or / and beams to report, etc.) and the reporting criteria, when these conditions are met, the WTRU will send a measurement report or perform the associated HO configuration in the case of CHO. The reporting criteria can be just the expiration of a periodic timer (periodic reporting configuration), or can be based on some radio conditions of the serving cell and / or neighboring cells. The WTRU 405 can be configured with up to 64 reporting configurations, and each reporting configuration is identified by a reporting configuration ID.

[0141] The WTRU 405 in the monitoring 410 can include measurement objects that can be associated with one or more reporting configurations. This association is done through the measurement ID. The measurement ID configuration is a list of measurement ID, measurement object ID, and reporting configuration ID. The WTRU 405 can be configured with up to 64 measurement IDs.

[0142] There are multiple ways to configure event-triggered reporting. These ways can include event A1 (the serving cell becomes better than a threshold), event A2 (the serving becomes worse than a threshold), event A3 (the neighbor offset becomes better than the SpCell), event A4 (the neighbor becomes better than a threshold), event A5 (the SpCell becomes worse than threshold 1 and the neighbor becomes better than threshold 2), event A6 (the neighbor offset becomes better than the SCell), event B1 (the inter-RAT neighbor becomes better than a threshold), and event B2 (the PCell becomes worse than threshold 1 and the inter-RAT neighbor becomes better than threshold 2). The term SpCell refers to the PCell (primary cell), or in the case of DC, refers to the primary-secondary cell (PSCell). Events A3, A5, B2 can be configured only for the PCell or PSCell. Events A1, A2, A3, A5, B2 can be configured for any serving cell. Event A6 can be configured only for the SCell (i.e., the secondary cell in carrier aggregation (CA)). Events A4 and B1 are only related to neighboring cell measurements (and thus not related to any serving cell). Each event configuration is associated with threshold (offset), hysteresis, and timeToTrigger (TTT) parameters.

[0143] In the case of CHO, when the reporting condition is met, the WTRU 405 executes an HO command at 420 instead of sending a measurement report. For CHO, the following event-triggered reporting configurations can be defined as CondEvent A3 (the neighbor offset becomes better than the SpCell), CondEvent A4 (the neighbor becomes better than a threshold), and CondEvent A5 (the SpCell becomes worse than threshold 1 and the neighbor becomes better than threshold 2).

[0144] The CHO configuration can include a conditional reconfiguration ID, a conditional reconfiguration trigger condition, and an RRC reconfiguration (i.e., an HO command) to be executed when the condition is met at 420.

[0145] The trigger conditions monitored by the WTRU 405 at 410 can reference 1 or 2 measurement IDs, and if 2 measurement IDs are specified, the two measurement IDs can reference the same measurement object (e.g., one measID associates a measurement object related to the PCell with an A3 event, while the other measID associates the same measurement object with an A5 event). Generally, the WTRU405 can be configured with up to 8 CHO configurations.

[0146] The WTRU 405 measurement configuration may include an s - measurement configuration (s - MeasureConfig) that specifies a threshold for NR SpCell RSRP measurement, which controls when the WTRU 405 needs to perform measurements on non - serving cells. That is, when the RSRP of the serving cell (e.g., the PCell) is higher than the s - measurement threshold, the WTRU 405 does not need to perform neighbor cell measurements, thus saving the WTRU battery.

[0147] Figure 5 Procedure 500 showing cell selection and reselection is presented. Procedure 500 provides a summary for, e.g., NR. The starting point of procedure 500 is whenever a new PLMN or a new SNPN is selected at 502. If cell information is stored for the PLMN or SNPN at 504, cell selection information is stored at 510. If no cell information is stored for the PLMN or SNPN at 506, an initial cell reselection occurs at 520.

[0148] When information related to cell selection is stored at 510, if no suitable cell is found at 512, an initial cell selection 520 may occur. If a suitable cell is found at 514, the cell may be camped on in the normal camping manner at 505.

[0149] When an initial cell selection is performed at 520, if no suitable cell is found at 518, any cell selection 525 may occur. If a suitable cell is found at 516, the cell may be camped on in the normal camping manner at 505.

[0150] When camping on a cell normally at 505, if a trigger occurs at 562, cell reselection and evaluation may be processed at 540, and the idle / inactive mode may be left at 558 and the connection mode 515 may be entered.

[0151] Starting from the connection mode 515, it may return to the idle / inactive mode 556 to return to cell selection when leaving the connection mode at 530. Starting from cell selection when leaving the connection mode at 530, if a suitable cell is found at 554, normal camping on the cell may occur at 505. If no suitable cell is found at 508, a return to storing information about cell selection may occur at 510.

[0152] When camping on normally at 505, at 522, a NAS message may indicate rejection of registration on the selected PLMN or the selected SNPN, and cell selection may occur at 525.

[0153] Through the cell reselection evaluation process 540, if a suitable cell is found at 568, it can be normally camped on at 505. If no suitable cell is found at 526, any cell selection can be performed at 525.

[0154] Through any cell selection 525, if a suitable cell is found at 532, the cell can be normally camped on at 505. If a USIM is inserted or an SNPN subscription is added at 528, the new PLMN or the new SNPN can be analyzed at 502. If an acceptable cell is found, a transition to the idle mode can occur at 534, and then any cell can be camped on at 535. If it is determined at 535 that a suitable cell is found at 536, the cell can be normally camped on at 505.

[0155] When camping on any cell 535, if any trigger occurs at 544, the cell reselection evaluation process can occur at 560. If an acceptable cell is found at 542 during reselection 560, the cell can be camped on at 535. If no acceptable cell is found at 538 via reselection 560, any cell selection 525 can be entered.

[0156] If any cell is camped on at 535 and the idle mode is maintained at 548, the connection mode can be entered at 545 for an emergency call. From there, when leaving the connection mode at 550, at 552, a return to the idle mode can occur to enter cell selection. If an acceptable cell is found at 546 during selection 550, the cell can be camped on at 535. If no acceptable cell is found at 572, selection 550 can lead to any cell selection 525.

[0157] As Figure 5 shown, there is a box 590 in the figure that highlights aspects related to the transition between RRC_CONNECTED and RRC_IDLE / RRC_INACTIVE (e.g., upon receiving an RRC release message or upon completion of temporary cell selection during RRC reconstruction), and when the WTRU is able to find a suitable cell to camp on (e.g., at 505). In addition, inter-RAT cell reselection is not considered.

[0158] When looking for a suitable cell ( Figure 5Multiple times), the WTRU searches for NR frequency bands and identifies the strongest cell for each carrier frequency based on CD-SSB. The WTRU reads the cell system information broadcast to identify its PLMN to find a suitable cell for camping. A suitable cell is a cell whose measured cell attributes meet the cell selection criteria; the cell PLMN is the selected PLMN, the registered or equivalent PLMN; the cell is not barred or reserved, and the cell is not part of a tracking area in the "roaming barred tracking area" list. When transitioning from RRC_CONNECTED to RRC_INACTIVE or RRC_IDLE, the WTRU may camp on a cell according to cell selection performed at the frequencies assigned by the RRC in the status transition message (if any). The cell selection criteria (referred to as criterion S) are met based on Equation 1, where:

[0159] Srxlev > 0 and Squal > 0 Equation 1

[0160] where Srxlev = Qrxlevmeas – (Qrxlevmin + Qrxlevminoffset) – Pcompensation – Qoffsettemp and Squal = Qqualmeas – (Qqualmin + Qqualminoffset) – Qoffsettemp, and where:

[0161]

[0162]

[0163]

[0164] When evaluating a cell for cell selection as a result of a periodic search for a higher-priority PLMN during normal camping in a VPLMN, only the signaled values of Qrxlevminoffset and Qqualminoffset may be applied. During this periodic search for a higher-priority PLMN, the WTRU may use parameter values stored from different cells of that higher-priority PLMN to check the S criterion of the cell.

[0165] For example, a WTRU in RRC_IDLE / RRC_INACTIVE performs cell reselection at 530, 550. The WTRU may perform intra-frequency, inter-frequency, or inter-RAT cell reselection. The WTRU is configured with priorities between RATs (e.g., pre-empt NR over LTE whenever an NR cell is available) or priorities between frequencies within the same RAT (e.g., fa has the highest priority, fb has medium priority, fc has the lowest priority, etc.). A neighbor cell list (NCL) may be provided to the WTRU, which indicates which neighbor cells (e.g., intra-frequency, inter-frequency, inter-RAT) cell reselection should consider. An allowed list may be provided to the WTRU, which only indicates the neighbor cells that reselection may consider. An exclusion list may be provided to the WTRU, which indicates the neighbor cells that reselection should not consider. The WTRU may attempt to pre-empt a cell operating at the highest priority RAT and / or highest priority frequency. If the serving cell satisfies Srxlev > SIntraSearchP and Squal > SIntraSearchQ, the WTRU may choose not to perform intra-frequency measurements; otherwise, the WTRU may perform intra-frequency measurements.

[0166] If the serving cell satisfies Srxlev > SnonIntraSearchP and Squal > SnonIntraSearchQ, the WTRU may choose not to perform measurements on NR inter-frequency cells with equal or lower priority or RAT inter-frequency cells with lower priority, otherwise, the WTRU may perform measurements on NR inter-frequency cells with equal or lower priority or RAT inter-frequency cells with lower priority.

[0167] SIntraSearchP specifies the Srxlev threshold (in dB) for intra-frequency measurements. SIntraSearchQ specifies the Squal threshold (in dB) for intra-frequency measurements. SnonIntraSearchP specifies the Srxlev threshold (in dB) for NR inter-frequency and inter-RAT measurements. SnonIntraSearchQ specifies the Squal threshold (in dB) for NR inter-frequency and inter-RAT measurements.

[0168] When the WTRU decides to perform intra-frequency measurements for cell reselection based on the above criteria, the WTRU may perform cell ranking of the relevant cells. Inter-frequency and inter-RAT reselection is based on absolute priorities, where the WTRU attempts to pre-empt the highest priority available frequency. The cell ranking criteria for the serving cell (Rs) and neighbor cells (Rn) (referred to as criterion R) are defined by Equation 2 and Equation 3.

[0169] Rs = Qmeas,s + Qhyst – Qoffsettemp Equation 2

[0170] Rn = Qmeas,n - Qoffset – Qoffsettemp Equation 3

[0171] Where:

[0172]

[0173] The WTRU may rank all cells that meet the cell selection criterion S defined above. The R value can be calculated by deriving Qmeas,n and Qmeas,s and using the average RSRP result, and the cells can be ranked according to the above R criterion. If rangeToBestCell is not configured, the WTRU may perform cell reselection to the cell with the highest rank. If rangeToBestCell is configured, the WTRU may perform cell reselection to the cell with the highest number of beams above a threshold (i.e., absThreshSS-BlocksConsolidation) among the cells within the range of rangeToBestCell of the R value of the cell with the highest rank. If there are multiple such cells, the WTRU may perform cell reselection to the cell with the highest rank among them.

[0174] The WTRU may reselect a new cell at 525 only when certain conditions are met. Such conditions include: the new cell is better than the serving cell according to the cell reselection criteria specified above within the time interval TreselectionRAT, and more than 1 second has elapsed since the WTRU pre-empted the current serving cell.

[0175] When a WTRU measures a target carrier frequency when it cannot simultaneously transmit / receive on the serving cell, the WTRU can use a measurement gap to perform the measurement. In the case of LTE, the WTRU requires a measurement gap to perform inter-frequency and inter-RAT measurements. A typical LTE gap length is 6 ms, which accommodates 5 ms of measurement time (PSS and SSS are transmitted every 5 ms) and 0.5 ms of RF retuning time before and after the measurement gap. The measurement gap repeats with a period of 40 ms or 80 ms. Similarly, in NR, the measurements performed by the WTRU can be gap-assisted (network-configured measurement gap) or non-gap-assisted. The use of measurement gaps in NR depends on the capabilities of the WTRU, the active BWP of the WTRU, and the current operating frequency. In NR, intra-frequency, inter-frequency, and inter-RAT measurements may require a measurement gap. Different from the intra-frequency case in LTE, intra-frequency measurements in NR may require a measurement gap, for example, in the case where an intra-frequency measurement is to be completed outside the active BWP. Measurement gap lengths of 1.5 ms, 3 ms, 3.5 ms, 4 ms, 5.5 ms, and 6 ms are defined in NR, where the measurement gap repetition period is 20 ms, 40 ms, 80 ms, and 160 ms.

[0176] In NR, the RF retuning time for carrier frequency measurements in FR1 (frequency range 1) is 0.5 ms, and for FR2 (frequency range 2) is 0.25 ms, where FR1 defines the frequency bands in the spectrum below 6 GHz, and FR2 defines the frequency bands in the mmWave (millimeter wave) spectrum. For example, a gap length of 4 ms for FR1 measurements will allow for an actual measurement of 3 ms, and a gap length of 3.5 ms for FR2 measurements will allow for an actual measurement of 3 ms. During the measurement gap, measurements will be performed on the SSBs of neighboring cells. The network provides the timing of the neighboring cell SSBs using the SS / PBCH block measurement timing configuration (SMTC).

[0177] The measurement gap and the SMTC duration are configured such that the WTRU can identify and measure the SSBs within the SMTC window, i.e., the SMTC duration should be sufficient to accommodate all the SSBs being transmitted.

[0178] For SSB-based intra-frequency measurements, if any WTRU-configured BWP does not contain the frequency domain resources of the SSB associated with the initial DL BWP, the network can configure a measurement gap.

[0179] For SSB-based inter-frequency measurements, if the WTRU supports per-FR measurement gaps and if the carrier frequency to be measured is in the same FR as any serving cell, the network may configure the measurement gap. For SSB-based inter-frequency measurements, if the WTRU only supports per-WTRU measurement gaps, the network may configure the measurement gap. In this case, the measurement object may be configured on any frequency range (FR1 or FR2), but the gap may be configured by the network.

[0180] Inter-RAT measurements in NR are limited to E-UTRA. For a WTRU configured for E-UTRA inter-RAT measurements, when the WTRU only supports per-WTRU measurement gaps, a measurement gap configuration may be provided; or the WTRU supports per-FR measurement gaps and at least one NR serving cell is in FR1. Two types of measurement gaps are defined in NR according to the WTRU's ability to support independent FR measurements and network preferences: per-WTRU and per-FR. In each FR gap, two independent gap patterns (i.e., FR1 gap and FR2 gap) are defined for FR1 and FR2 respectively. Each per-WTRU gap applies to both FR1 (E-UTRA and NR) and FR2 (NR) frequencies.

[0181] The main parameters of the measurement gap configuration include mgrp (measurement gap repetition period) which is the period (in ms) for which the measurement gap repeats. Periods of 20 ms, 40 ms, 80 ms, and 160 ms are defined in NR.

[0182] The main parameters of the measurement gap configuration include gapOffset which is the gap offset of the gap pattern. Not all 160 offset values are applicable to all periodicities. Since the offset value points to the starting subframe within the period, its value range is from 0 to mgrp - 1. For example, if the periodicity is 40 ms, the offset range is from 0 to 39.

[0183] The main parameters of the measurement gap configuration include mgl (measurement gap length) which is the length (in ms) of the measurement gap. Measurement gap lengths of 1.5 ms, 3 ms, 3.5 ms, 4 ms, 5.5 ms, and 6 ms are defined in NR.

[0184] The main parameters of the measurement gap configuration include mgta (measurement gap timing advance). If this parameter is configured, the WTRU will start measuring mgta ms before the gap subframe occurs, i.e., the measurement gap starts at a time mgta ms advanced to the end of the latest subframe that occurred immediately before the measurement gap. The timing advance amount can be 0.25 ms (FR2) or 0.5 ms (FR1).

[0185] The WTRU may be configured with multiple measurement gap configurations.

[0186] Network energy consumption can be significant and in some cases unnecessary, such as during quiet periods. The network can turn off small cells and rely on macro cells for coverage during quiet periods, completely turn off certain sectors or gNBs, reduce PA power consumption, and / or enable the gNB - side sleep mode without significantly sacrificing WTRU performance. The gNB makes this decision by combining information including WTRU measurements, WTRU - assisted information, interference status, load information, and proprietary information.

[0187] From the perspective of the WTRU, when the capacity of certain cells is an active NES, the WTRU can experience coverage loss and may not know that the gNB is in the NES state (e.g., deep sleep or hibernation), especially in the IDLE state and INACTIVE state. Adjusting network availability resources requires adapting to how the WTRU knows whether common cell signals (e.g., SSB, paging, SI) are being transmitted as normal rather than being unable to receive them due to poor channel conditions.

[0188] When the gNB sleeps or shuts down, some WTRU control - plane procedures for connection management, WTRU reachability, cell reselection, and WTRU battery consumption can be affected, including inter - cell mobility and reselection as well as WTRU measurements.

[0189] For inter - cell mobility and reselection, when the gNB shuts down or enters the hibernation or deep - sleep state, the network may want to offload / switch the remaining WTRUs to other cells in the area. Executing handover commands / RRC reconfigurations for each remaining WTRU requires multiple signaling and can delay the time for the gNB to enter the sleep state. For idle - mode WTRUs, the network does not know which WTRUs are camped on it. One problem is how to select CHO candidates for mobility when the serving cell shuts down / sleeps, especially when some candidate cells may be in the sleep mode, may support both legacy and NES - capable WTRUs simultaneously, and / or may be more suitable for a subset of services (e.g., eMBB or IoT). In addition, the WTRU can initiate inter - cell / inter - frequency measurements on neighboring cells before the serving cell shuts down or enters the sleep state or when an NES cell wakes up.

[0190] For WTRU measurements, when the network changes its sleep state, some measurement resources for mobility or cell reselection may not be applicable. Given that the sleep state and gNB on / off state change dynamically, relying on the existing framework requires the network to dynamically send RRC reconfiguration messages to each WTRU in the cell every time the gNB enters the sleep or off state, which incurs a large amount of overhead and may also delay the gNB sleep start time.

[0191] The terms "energy saving mode", "NES state", "availability state", "power saving mode", "cell DTX state / mode", and "sleep mode" are used interchangeably. When a cell is in full power operation, it can be considered to have no NES state, or it has a "normal mode" or "full power operation" NES state. A change in the NES state can be indicated to the WTRU directly (e.g., group DCI, broadcast message, etc.) or implicitly (e.g., the WTRU notices a change in the SSB mode, etc.).

[0192] The WTRU can consider one NES state as the cell DTX or the cell DRX being active, and another NES state as the cell DTX and / or the cell DRX being inactive. The WTRU can consider the NES state during the active period of the active cell DTX / DRX, while the WTRU can consider another NES state during the inactive period of the configured active cell DTX and / or DRX. The WTRU can consider a separate NES state for each cell DTX and / or cell DRX configuration.

[0193] The cell DTX active period can correspond to the WTRU's C-DRX on-duration or active time, while the cell DTX inactive period can correspond to the WTRU's C-DRX inactive time. The WTRU can consider one NES state when a subset of spatial elements (e.g., number of ports, number of elements) is activated or deactivated, and another NES state when a different subset of spatial elements is activated or deactivated. The WTRU can consider one NES state when the PDSCH power is reduced (e.g., for the CSI-RS power offset, the WTRU indicates a different PDSCH), and another NES state when the PA operates according to traditional assumptions or there is no PDSCH power reduction. The WTRU can consider a cell in the NES state when the PA power is reduced (for all channels or a subset of channels), if the power increase of a subset of channels changes, and / or if the PA operates in a low efficiency state (e.g., in a configuration corresponding to a lower input bias current).

[0194] Cell DTX inactive period: The duration for which the configured cell DTX mode is inactive / inactive (e.g., the time period outside the periodic on-duration of the cell DTX mode). This can only apply after the NW has indicated to activate the cell DTX configuration. Activated cell DRX / DTX: The state of the configured cell DRX or cell DTX mode, where this state has been activated via L1 / L2 DL signaling, RRC (re)configuration, and / or cell general configuration and has not been deactivated.

[0195] For the connected mode, the WTRU may start mobility-related measurements (e.g., channel conditions, interference measurement resources (IMR), or CHO-related measurements), including inter-cell, inter-frequency, and / or inter-RAT measurements, after receiving NES state change signaling, or determining an NES state change on the serving cell, or a cell DTX indication related to the serving cell or a neighboring cell (e.g., an instance between 0 and t1). The WTRU may start mobility-related measurements (e.g., channel conditions or CHO-related measurements), including inter-cell, inter-frequency, and / or inter-RAT measurements, after meeting at least one of the conditions listed above for NES-specific CHO conditions and selection (e.g., the serving cell changes its NES state, the serving cell activates cell DTX, a neighboring cell changes its NES state, a neighboring cell activates DTX), based on the active period / on-duration of the serving cell entering its configured cell DTX mode and / or based on the active period / on-duration of a neighboring cell entering its configured cell DTX mode). For a neighboring cell, if the neighboring cell DTX mode configuration is provided by the serving cell, the UE may start related inter-cell measurements during the cell DTX on-duration of the neighboring cell. The WTRU may even start such measurements before receiving or determining an NES state change of the serving cell, which may be triggered by receiving an indication or signaling from the NW (e.g., group common L1 / L2 signaling (e.g., for cell DTX), broadcast signaling or configuration, or an RRC reconfiguration message), and the WTRU may start a timer after receiving such an indication to perform the measurements within a configured or predetermined time window (t2). The WTRU may report the measurements before t2 expires. This may enable the gNB to know whether it is entering sleep, deep sleep, or shutdown, and / or by how much it can reduce its PA power efficiency, and also enable the gNB to transition to the NES state at different times (non-static) after the WTRU starts performing and reporting the measurements.

[0196] For NES-specific CHO conditions and selection, cells configured as a secondary cell, cells in the same DU, cells in the same site, cells with a known cell DTX configuration, or cells serving only NES-capable WTRUs, the WTRU may measure candidate cells selected according to the methods described herein.

[0197] A WTRU in the CONNECTED state can be configured with different s - measurement configurations for different NES states of the serving cell, e.g., depending on whether the cell has activated cell DTX. For example, the WTRU can be configured with a set of s - measurement configurations, each associated with one or more NES states. For example, when the WTRU can apply the following s - measurement thresholds: RSRP_threshold_1: NES state 1, normal mode (e.g., on or active downlink and / or uplink); RSRP_threshold_2: NES state 2, micro - sleep mode; RSRP_threshold_3: NES state 3, light - sleep mode; RSRP_threshold_4: NES state 4, deep - sleep mode; RSRP threshold 5: NES state 5, reduced power or PA - efficient state; etc., where RSRP_threshold_1 < RSRP_threshold_2 < RSRP_threshold_3 < RSRP_threshold_4, etc. That is, the deeper the sleep mode, the more aggressively the WTRU can perform measurements on the secondary cell (i.e., even if the conditions of the serving cell are very good from the perspective of signal level).

[0198] Rather than being configured with different S - measurement thresholds for each NES state, the WTRU can be configured with one S - measurement threshold (in the traditional way) to be applied when the serving cell is in the full - power mode, but is configured with a scaling factor or offset to be applied to each NES state, and whenever the NES state of the serving cell changes, the WTRU updates the S - measurement value according to the scaling factor or offset and the current NES state. The scaling factor can be provided via dedicated signaling (e.g., as part of the S - measurement configuration), or it can be provided via broadcast signaling (e.g., the same scaling factor applicable to the WTRUs in the cell).

[0199] The S - measurement configuration can depend on the direction of the NES state transition. For example, when the NES state changes from NES state 1 to NES state 3, a certain S - measurement applies, and when the NES state changes from NES state 2 to NES state 3, another S - measurement configuration applies, etc.

[0200] The S-measurement configuration can be extended to cover different types of neighboring cells. For example, different S-measurements (or scaling factors) can be configured for different types of measurements (e.g., a set of S-measurements related to in-band measurements, a set of S-measurements related to inter-band measurements, a set of S-measurements related to inter-RAT measurements, etc.), and these S-measurement configurations can be associated with the NES state. For example, the WTRU can receive an S-measurement configuration for in-band measurements and another S-measurement for inter-band measurements, where each S-measurement configuration can also have different thresholds for different NES states.

[0201] The WTRU can be configured with different measurement gap configurations to be applied to in-band measurements, inter-band measurements, or / and inter-RAT measurements depending on the NES state of the serving cell. For example, the WTRU can measure or skip the measurement opportunity of a given cell based on the cell DTX activity of the cell, where the WTRU can perform measurements at the measurement opportunity that overlaps with the cell DTX activity period / on duration of the cell. The measurements can include L1, L2, and / or L3 measurements.

[0202] Each measurement gap configuration can be associated with one or more NES states of the serving cell or / and the target cell (e.g., whether the cell has active cell DTX) (e.g., the IE in the measurement gap configuration specifies the NES state or the state to which the measurement gap is to be applied, the IE in the measurement gap configuration specifies the NES state or the state to which the measurement gap configuration will not be applied, etc.). For example, if the measurement gap configuration indicates that it will be applied in light sleep, the WTRU can not apply the measurement gap and perform the associated in-band / inter-band measurements or inter-RAT measurements until it determines that the serving cell has started operating in the light sleep mode). In another example, if the measurement gap configuration associated with a cell indicates that it will be applied during the sleep / cell DTX activity mode, the WTRU can not apply the measurement gap and perform the associated in-band / inter-band measurements or inter-RAT measurements until it determines that the cell has activated cell DTX (whether the cell is the serving cell or a neighboring cell) and the cell is transmitting the relevant measurement signal during the measurement gap (e.g., during the cell DTX on duration of the associated cell).

[0203] The WTRU may be configured with a baseline configuration that applies when the serving cell is operating in full power mode, rather than configuring different measurement gap configurations for different NES states, and may configure scaling factors, offsets, or factors associated with different NES states or cell DTX, and the WTRU may apply these scaling factors on top of the baseline measurement gap configuration. For example, the WTRU may be configured to apply a scaling factor on the measurement gap length or measurement gap repetition period based on the NES state (for a given NES state, the scaling factor may be the same for both the measurement gap length and the repetition period, or different scaling factors may be provided for each parameter for each NES state).

[0204] The scaling factor may be specified at a given measurement gap configuration level. The scaling factor may be specified as applying (being common) to all measurement gap configurations. The scaling factor may be specified as applying (being common) to a subset of the WTRU's measurement gap configurations (e.g., only applying to FR1 gaps, only applying to FR2 gaps, only applying to each WTRU gap, only applying to a list of explicitly configured measurement gap configurations). The scaling factor may be provided via dedicated signaling (e.g., as part of MeasConfig), or it may be provided via broadcast signaling (e.g., the same scaling factor applying to the WTRUs in the cell).

[0205] The measurement gap configuration may depend on the direction of the NES state transition. For example, when the NES state changes from NES state 1 to NES state 3, a certain measurement gap configuration applies, and when the NES state changes from NES state 2 to NES state 3, another measurement gap configuration applies, and so on. For example, when the cell DTX mode changes from active to inactive, a certain measurement gap configuration may apply, when the cell DTX is (de)activated, a certain measurement gap configuration may apply, and when the cell DTX mode changes from inactive to active, another measurement gap configuration may apply. The cell DTX mode configuration may be associated with one or more measurement gap configurations.

[0206] The WTRU may be configured to continue applying a certain measurement gap configuration (or a scaled / updated measurement gap configuration based on the change in the NES state) as long as the NES state returns to the state before the measurement gap became active. For example, if the measurement gap configuration becomes active when the NES state changes from light sleep to medium sleep, the WTRU may continue to use that measurement gap when the NES state of the serving cell changes from medium sleep to deep sleep or back to medium sleep, but may stop using that measurement gap when the NES state changes back to the light sleep mode again. In another example, if the measurement gap configuration becomes active based on the activation of the cell DTX, the WTRU may stop using that measurement gap when the cell DTX is deactivated.

[0207] The WTRU may be configured with different measurement object configurations that are associated with one or more NES states and / or cell DTX configurations of the serving cell and / or neighboring cells. For example, an IE may be introduced in the measObjectNR or measObjectToAddModList IE that indicates which NES states the measurement object is related to or associated with. In another example, the IE may indicate which NES states the measurement object is not related to, such as whether the measurement configuration is applicable to cell DTX or a specific cell DTX configuration. In another example, an IE (e.g., in MeasConfig) may be introduced that indicates the mapping / association between the measurement object and NES states (e.g., NES state 1: measobject ID1, measobjectID2; NES state 2: measobject ID1, measobject ID3, etc.). The WTRU may determine such configurations in the configured part of the HO command and / or the CHO candidate list (e.g., the source cell provides the cell DTX and / or cell DRX configuration associated with the target cell). The WTRU may receive the configuration of the cell DTX mode associated with the neighboring cell from the source cell so that it knows when to perform mobility and RRM measurements on the neighboring cell.

[0208] The WTRU may be configured with different measurement report / event configurations that are associated with one or more NES states of the serving cell and / or neighboring cells. For example, an IE may be introduced in the reportConfigNR or reportConfigToAddModList IE that indicates which NES states the measurement report / event configuration is related to or associated with. In another example, the IE may indicate which NES states the measurement report / event configuration is not related to. In another example, an IE (e.g., in MeasConfig) may be introduced that indicates the mapping / association between the measurement report / event configuration and NES states (e.g., NES state 1: reportConfig ID1, reportConfig ID2; NES state 2: reportConfig ID1, reportConfig ID3, etc.).

[0209] A WTRU may be configured with different measurement ID configurations that are associated with one or more NES states of a serving cell and / or neighboring cells. For example, an IE may be introduced in the measIDToAddMod IE that indicates which NES states the measurement ID configuration is related or associated with. In another example, the IE may indicate which NES states the measurement ID configuration is not related to. In another example, an IE (e.g., in MeasConfig) may be introduced that indicates the mapping / association between the measurement ID and NES states (e.g., NES state 1: meas ID1, meas ID2; NES state 2: meas ID1, meas ID3, etc.).

[0210] In one example, when the NES state changes to a state that is not associated with a measurement object, measurement report, or meas ID, the WTRU may deactivate the measurement object, measurement report, measurement resource, or meas ID configuration.

[0211] For example, when the NES state changes to a state that is not associated with a given measID, the WTRU may stop performing measurements at the frequency / RAT of the measurement object associated with this measurement ID.

[0212] In addition, for example, when the NES state changes to a state that is not associated with a given reportConfig, the WTRU may stop monitoring the conditions that trigger the execution of a measurement report or CHO in this report configuration (for any measurement object in the measurement ID that is associated with this report configuration), but it may still continue to perform measurements (as long as the associated measID and / or measObject is associated with the current NES state). When Cell DTX is activated and the measID is associated with the cell DTX, the WTRU may start performing measurements at the frequency / RAT of the measurement object associated with this measurement ID. When the cell DTX is deactivated, the UE may stop performing such measurements; when the cell DTX is activated and the measID is not associated with the inactive period of the cell DTX, the WTRU may stop performing measurements at the frequency / RAT of the measurement object associated with this measurement ID during the inactive period of the cell DTX (e.g., outside the cell DTX on duration).

[0213] In one example, when the NES state changes to a state associated with a measurement object, measurement report, or meas ID, the WTRU may activate a deactivated measurement object, measurement report, or meas ID configuration. For example, when the NES state changes to a state associated with a given meas ID, the WTRU may start performing measurements at the frequency / RAT of the measurement object associated with this measurement ID. If the reportConfig associated with this meas ID is also associated with the current NES state, the WTRU may start monitoring the measurement reports or CHO trigger conditions indicated in the reportConfig

[0214] The WTRU may be configured to publish all measurement results associated with a given meas ID and / or measObject configuration when the meas ID and / or measObject is deactivated. For example, the WTRU may be configured to publish all measurement results associated with a given meas ID and / or measObject configuration when the NES state is reconfigured (e.g., when reconfiguring cell DTX).

[0215] The WTRU may be configured to retain all measurement results associated with a given meas ID and / or measObject configuration when the meas ID and / or measObject is deactivated.

[0216] It should be noted that the maximum number of measurement objects, measurement reports, and ID configurations that the WTRU can configure is currently limited. Specifically, maxNrofObjectId = 64, maxReportConfigId = 64, and maxNrofMeasId = 64. In addition, the WTRU capabilities may further limit these maximum values. For example, a low-capability WTRU may only be able to perform 8 measurements at a time (i.e., maxNrofMeasID = 8).

[0217] Using the included method of associating measurement objects, reports, and ID configurations with the NES state described above allows for the WTRU to be configured with more configurations than are allowed in the specification (and the WTRU is capable of this) because not all configurations are active / relevant for a given NES state of the serving cell, and the serving cell can only be in one NES state at a given time. The concepts discussed above can even be extended to the sub-elements of a given measurement object configuration. For example, the quantity configurations associated with a given measurement object (including information such as L3 filtering coefficients) may be configured to depend on the NES state (e.g., a given measurement object is configured with multiple quantity configurations, where each configuration is associated with a given NES state, and the WTRU applies the configuration associated with the current NES state of the serving cell).

[0218] NES status change indications received by the WTRU may include time information (e.g., the NES status changes to medium sleep within x ms, cell DTX activation time, DTX on duration to start periodically, etc.). In such cases, the WTRU may use any of the above solutions to perform updates to s-measurements, measurement objects, measurement reports, measurement IDs, and / or measurement gaps in one or more of the following ways. The WTRU may perform immediately upon receipt of the NES status change indication. The WTRU may perform when the NES status change becomes effective (e.g., a timer started with a value equal to the indicated expected NES status change expires, during the on duration of the cell DTX mode, etc.). The WTRU may perform at any time between receipt of the indication of the NES status change (or expected change) and when the NES status change actually becomes effective. The WTRU may decide to apply immediately or when the NES change becomes effective, depending on the current and upcoming NES status changes. For example, if the NES status changes from full operation mode to light sleep, the WTRU may wait until the indicated time of the NES status change to perform updates to any relevant measurement configurations, while if the NES status changes from light sleep mode to deep sleep (or full off), the WTRU may perform all relevant measurement configuration updates immediately without waiting until the NES status change becomes effective. The WTRU may perform based on current WTRU conditions (such as battery level, UL buffer level, UL / DL data rate, active bearer / traffic type, etc.) (e.g., if the UL buffer level is above a certain threshold, apply the updates immediately, but if the UL buffer level is below a certain threshold, wait until the NES status change becomes effective).

[0219] The WTRU may send an indication to the network regarding a change in its behavior related to any change associated with the above-mentioned measurement configuration (e.g., S-measurement update, measurement gap update, activation / deactivation of measurement objects, reporting configuration, or measurement ID, etc.). This indication may be sent when it has updated the configuration. This indication may be sent when it starts performing neighbor measurements due to an updated configuration (e.g., due to an S-measurement change, due to the activation of a measurement ID, due to the application of a measurement gap, etc.). This indication may be sent when a measurement report is triggered afterwards / due to a configuration change. This indication may be sent when CHO is performed afterwards / due to a configuration change. The WTRU may not immediately send an indication to the network regarding such a change in behavior related to the configuration associated with any of the above-mentioned measurements, but may store it in a log / information. The WTRU may indicate, for example, in a WTRU assistance information message, a NES assistance information message, an RRC reconfiguration complete message, an HO complete message, etc.) that it has such available information. The network may request this information at any time, either as a response to an indication that this information is available from the WTRU. The WTRU may also send this indication in a timely manner via another message (e.g., in an HO complete message, in a reconfiguration complete message, etc.).

[0220] Other measurements in connected BFD / RLM / RRM / CSI may also be performed.

[0221] The WTRU may be configured with different mobility or cell reselection measurement resources for each NES state, including measurement objects, IDs, gaps, reporting configurations, and / or quantity configurations. The WTRU may apply a set of measurement configurations / resources based on the NES state associated with the source cell, target cell, pre-emptive cell, candidate cells to be reselected, and / or frequency layers to be reselected.

[0222] BFD / RLM / RRM or CSI measurements may be relaxed during a cell DTX inactivity period or NES state. When cell DTX and / or cell DRX are activated, the WTRU may suspend L1 / L2 / L3 measurement opportunities. When cell DTX is active, the WTRU may relax BFD, RLM, RRM, CSI, IMR measurements. During a cell DTX inactivity period, the WTRU may suspend CSI measurements and beam management, for example if SSB or RS is not transmitted according to traditional assumptions.

[0223] If cell DTX is active and / or during a cell DTX inactive period, the WTRU may maintain one or more sets of minimum requirements for CSI-RS- and / or SSB-based beam failure detection such that the WTRU meets relaxed measurement criteria. If cell DTX is active and / or during a cell DTX inactive period, the WTRU may maintain one or more sets of minimum requirements for CSI-RS- and / or SSB-based radio link monitoring such that the WTRU meets relaxed measurement criteria. When cell DTX configuration is active in the serving cell, the WTRU may be configured with an alternate T DRX period for applying measurements. If cell DTX configuration is active, the UE may replace T CSI-RS with max(cell DTX period, T CSI-RS ) when performing BFD / RLM / RRM / CSI measurements.

[0224] L1 measurements may occur where no SSB inter-band SCell activation is expected. In one deployment scenario, the WTRU may be configured with one or more CSI-RS configurations per SCell, each SSB-less SCell being associated with an SSB transmitted on the PCell or another anchor SCell. The WTRU may start performing measurements on such CSI-RS resources when or before receiving an SCell activation command, and / or synchronize with the SSB transmitted on the PCell or another anchor SCell. The WTRU may adjust the time-frequency synchronization determined based on the SSB measurement on the PCell by applying a frequency or time shift according to the measured CSI-RS from the SSB-less SCell.

[0225] In the case of an SSB-less Scell configuration, immediately following the issuance of an Scell activation command, the WTRU may assume that the CSI-RS broadcast on the Scell for further measurements is QCL with the SSB on the Pcell or PScell in its designated CG (cell group), and may thus apply the same spatial filter to Scell reception. Since full activation of the Scell is only obtained after transmitting a valid (in-range) CQI to the network, which means that Scell PDCCH reception and decoding is ready, the network may expedite the process of sending a CSI-RS aperiodic measurement request on the Pcell DCI for inter-cell measurements, which may be sent on the PUCCH or PUSCH UCI on the Pcell UL. After full Scell activation and the first CSI-RS feedback from the Scell, or alternatively after decoding the first PDCCH on the Scell, the WTRU may follow the measurements of its CSI-RS configuration in the new carrier aggregation state.

[0226] In a carrier aggregation scenario, when a WTRU is configured with a Scell without SSB, the WTRU beam management on the Scell can be fully based on CSI-RS. Since the inter-band situation has different propagation characteristics between bands, the beamwidth can be different and the path loss can also be different. Therefore, even if the Pcell and the Scell can be quasi-co-located, the RLM and RLF on the Scell can have different behaviors.

[0227] If a beam failure is declared on the Scell while the Pcell remains in a synchronized and functional state, the beam failure message can be sent on the Pcell. One of the problems is how to replace the beam when there is no SSB on the Scell.

[0228] In one solution, a conditional beam change procedure can be applied. The network can pre-configure the beam in this SSB-less cell for the WTRU, such as a beam adjacent to the active beam, which can be activated when the WTRU has a first beam failure on the Scell, and the associated CSI-RS-measurements on the secondary beam group.

[0229] Alternatively, for an SSB-less Scell with a pre-configured conditional beam change procedure, the beam change mechanism can be associated with a CSI-RS-measurement threshold, which can trigger a report from the WTRU before RLF occurs on the SSB-less beam of the Scell. The pre-configured set of beam changes can have its own CSI-RS configuration, which the WTRU can measure. The WTRU report that triggers the measurement threshold can be that the absolute RSRP level of the serving beam is lower than a certain quality, or the relative increment between the active beam and the prepared beam candidate on the Scell in favor of the candidate beam.

[0230] After the WTRU report is triggered by the beam change procedure, the WTRU can start scanning the PDCCH of the candidate beams as well as the active PDCCH. The first detected correct PDCCH addressed to the WTRU on the candidate beam can mark the success of the conditional beam change.

[0231] The WTRU can be configured with different measurement object configurations, which are associated with operating with DRS and / or SSB in the serving cell with a longer periodicity.

[0232] L1 measurements may occur triggered by spatial adaptation. The WTRU may be configured with different measurement object configurations that are associated with one or more NES states or spatial element activation states of the serving cell and / or neighboring cells. For example, the measurement resource configuration may indicate which spatial element configuration a measurement object is related or associated with. After determining or receiving an indication that the number of active spatial elements has changed, the WTRU may change the measurement configuration to match the spatial element activation state of the serving cell.

[0233] L1 measurements may occur triggered by a change in PA power reduction or CSI RS power boost. The WTRU may be configured to measure and / or report CSI measurements (e.g., multiple CSI reports in a single report) to reflect different PA configurations, power offsets, number of active spatial elements, and / or gNB transmit power configurations.

[0234] The WTRU may be configured with multiple CSI report configurations, and the WTRU may select an appropriate configuration for PUCCH reporting based on the report payload size and / or the number of CSI reports combined together.

[0235] If the serving cell has activated a certain NES state (e.g., cell DTX, reduction in the number of spatial elements, PA power reduction, change in CSI-RS to PDSCH power offset), the WTRU may (e.g., during the PHR or RACH procedure) add an offset to the masked path loss, CSI-RS-measurement, and / or PRS-measurement of the serving cell, or estimate the path loss / measurement in a different way, where the offset may depend on the NES state. The WTRU may apply such an offset and / or change the path loss estimate depending on whether the DL power is reduced for all DL channels / signals or only for a subset (e.g., only for data channels). If the CSI-RS power boost (relative to other data channels) changes from the default configuration value of a legacy WTRU, the WTRU may apply such an offset and / or change the path loss estimate. If an indication of the NES state configuration may be provided by the source cell, the WTRU may apply such an offset to neighboring cells for mobility or RRM measurements.

[0236] Measurements may occur in the IDLE / INACTIVE mode. For example, these measurements may include mobility measurements for cell selection or reselection in the IDLE / INACTIVE state. In the IDLE / INACTIVE state, the WTRU may be configured to change its cell selection (S-criterion) based on the NES state of the relevant cell in order to perform cell selection (as described above). For example, the WTRU may be configured with different parameters / offset values for calculating Srexlev and / or Squal for different NES states of the relevant cell (e.g., different sets of values for Qrxlevmin, Qqualmin, Qrxlevminoffset, Qqualminoffset, and / or Qoffsettemp for different NES states of the relevant cell being evaluated for the S-criterion for cell selection). Alternatively, the WTRU may be configured with a set of values for cell selection parameters for the normal mode (i.e., no power saving), and a scaling factor applied to these values for each NES state. The scaling factor may be the same for each value of a given NES state, or different scaling factors may be configured for each cell selection related parameter.

[0237] In the IDLE / INACTIVE state, the WTRU may be configured to change the criteria for initiating in-frequency measurements for cell reselection (as described above), depending on the NES state of the serving cell. For example, the WTRU may be configured with different SIntraSearchP and / or SIntraSearchQ values for each NES state. Alternatively, the WTRU may be configured with a pair of SIntraSearchP / SIntraSearchQ values for the normal mode (i.e., no power saving), and a scaling factor applied to these values for each NES state. The scaling factor may be the same for both SIntraSearchP and SIntraSearchQ, or different scaling factors may be configured for SIntraSearchP and SIntraSearchQ.

[0238] In the IDLE / INACTIVE state, the WTRU may be configured to change its criteria for initiating inter-frequency or inter-RAT measurements for cell reselection (as described above), depending on the NES state of the serving cell. For example, the WTRU may be configured with different SnonIntraSearchP and / or SnonIntraSearchQ values for each NES state. Alternatively, the WTRU may be configured with a pair of SnonIntraSearchP / SnonIntraSearchQ values for normal mode (i.e., no power saving), and a scaling factor may be applied to these values for each NES state. The scaling factor may be the same for both SnonIntraSearchP and SnonIntraSearchQ, or different scaling factors may be configured for SnonIntraSearchP and SnonIntraSearchQ.

[0239] In the IDLE / INACTIVE state, the WTRU may be configured to change its cell ranking (criterion R) for cell reselection (as described above), depending on the NES state of the serving cell and / or neighboring cells. For example, the WTRU may be configured with different Qhyst values for different NES states of the serving cell. For example, the WTRU may be configured with different Qoffset values for different NES states of neighboring cells. Alternatively, the WTRU may be configured with a Qhyst value for normal mode (i.e., no power saving in the serving cell), and a scaling factor may be applied to this value for each NES state of the serving cell. Similarly, the WTRU may be configured with a Qoffset value for normal mode (i.e., no power saving in the relevant neighboring cells), and a scaling factor may be applied to this value for each NES state of the neighboring cells. For a given NES state, the scaling factors for Qhyst and Qoffset may be the same, or different scaling factors may be configured for Qhyst and Qoffset.

[0240] In an idle / inactive state, the WTRU may start such measurements even before receiving or determining a change in the NES state of the serving cell, which may be triggered by receiving an indication or signaling from the NW (e.g., group common L1 / L2 signaling, broadcast signaling (e.g., part of the NES SIB) or configuration, or an RRC reconfiguration message), and the WTRU may start a timer after receiving such an indication to perform the measurements within a configured or predefined time window. The WTRU may measure only a subset of cells or frequency layers that meet the conditions described herein for NES-specific CHO conditions and selections, cells that indicate or prioritize a part of that indication (e.g., part of the NES SIB), cells configured as a secondary cell, etc. After receiving such an indication, the WTRU may start the measurements even if the current measurement results on the pre-empted cell and / or frequency layer are higher than the thresholds configured for cell selection. The indication may also indicate a list of cells to be measured, measurement resources (measurement objects, IDs, gaps, reporting configurations, and / or quantity configurations), associated priorities for cell reselection, and / or associated NES states.

[0241] The NES state change indication received by the WTRU may include time information (e.g., the NES state changes to medium sleep within x ms). In this case, the WTRU may perform an update of the cell reselection configuration / behavior change in one or more of the following ways according to any of the above solutions. The WTRU may perform the update immediately after receiving the NES state change indication. The WTRU may perform the update when the NES state change becomes effective (e.g., when a timer started with a value equal to the expected NES state change indicated expires). The WTRU may perform the update at any time between receiving the indication of the NES state change (or expected change) and when the NES state change actually becomes effective. The WTRU may decide to apply immediately or when the NES change becomes effective, depending on the current and upcoming NES state changes. For example, if the NES state changes from a fully operational mode to a light sleep, the WTRU may wait until the indicated time of the NES state change to perform any relevant cell reselection configuration / behavior updates, while if the NES state changes from a light sleep mode to a deep sleep (or fully off), the WTRU may immediately perform all relevant cell reselection configuration / behavior updates without waiting until the NES state change becomes effective. The WTRU may perform the update according to the current WTRU conditions (such as battery level, configured bearer / traffic type, etc.) (e.g., when in the INACTIVE state, if the WTRU has a bearer that is very sensitive to latency, apply the update immediately, otherwise wait until the NES state change becomes effective).

[0242] The WTRU may send an indication to the network regarding a change in its behavior that is related to any change associated with the above-mentioned cell reselection. However, since the WTRU is in the IDLE / INACTIVE state, it is not desirable to send these indications every time a configuration / behavior change occurs according to any of the above solutions. Instead, the WTRU may save the changes in a log and send the changes to the network when it transitions to the CONNECTED mode. For example, the log may be part of some other information that the WTRU saves while in the IDLE / INACTIVE mode, such as the WTRU mobility history (e.g., the stored cell reselection history therein may indicate additional details regarding the cell reselection behavior / configuration at that time, such as a cell reselection that occurred due to an update of cell reselection parameters / thresholds triggered by a change in the NES state of the serving cell or a neighboring cell).

[0243] Figure 6 Example 600 is shown. In Example 600, the NES state may be associated with cell DTX, cell shutdown, or the state prior to cell shutdown. The measurement configuration may include an ID, a measurement gap, measurement objects, and / or measurement reporting configuration parameters as described herein. The measurements of the WTRU may include inter-cell, inter-frequency, inter-RAT, BFD, RRM, and / or RLM measurements or examples. When the cell is not in the NES state, at 610, Example 600 includes the WTRU receiving one or more measurement configurations from the cell, where each configuration includes information indicating to which network energy saving stack (NES) state the configuration applies.

[0244] Preparation may be made for a first NES state. At 620, the WTRU receives signaling associated with activating the first NES state and determines which measurement configurations are applicable to the first NES state. The signaling may include, for example, an explicit NES indication or a CHO reconfiguration associated with the NES. The signaling may be an explicit layer 1, layer 2, or CHO configuration.

[0245] During time window 640, the WTRU performs and reports measurements using the NES measurement configurations applicable to the first NES state. The WTRU may stop performing measurements other than the NES-configured measurements. Time window 640t may be configured at 610 and / or indicated by NES signaling at 620.

[0246] At 650, the cell is in the first NES state (i.e., the cell is shutdown). The cell may be in a second NES state or not in the NES state. At 630, the WTRU receives signaling associated with activating the second NES state or deactivating the NES. In the case of deactivation, the WTRU may use one or more measurement configurations that are not associated with any NES state (i.e., regular measurements).

[0247] Figure 7 Method 700 for WTRU measurements in an energy saving network is shown. Method 700 includes receiving, at 710, a measurement configuration from a cell. The measurement configuration may include information indicating the NES state to which the configuration applies. At 720, method 700 includes receiving a signal associated with activating a first NES state. For example, these signals may be explicit NES indications or CHO reconfiguration messages associated with NES states. The signal may be explicit in layer 1 or layer 2 or CHO configuration.

[0248] At 730, method 700 includes determining the measurement configuration applied to the first NES state. At 740, method 700 performs and reports measurements using the determined NES measurement configuration applied to the first NES state. At 750, method 700 includes receiving signaling associated with activating a second NES state or deactivating the NES state. If deactivation occurs, the WTRU may use one or more measurement configurations not associated with any NES state (i.e., conventional measurements).

[0249] Figure 8 Method 800 performed in a WTRU is shown. Method 800 includes receiving, at 810, configuration information indicating one or more measurement configurations, where each of the one or more measurement configurations includes NES state information indicating one or more network energy saving (NES) states to which the measurement configuration applies. At 820, method 800 includes receiving signaling associated with activating a first NES state among the one or more indicated NES states. At 830, method 800 includes determining, based on the received information, the measurement configuration applicable to the first NES state. At 840, method 800 includes performing one or more measurements using the determined measurement configuration. At 850, method 800 includes reporting the one or more measurements. In method 800, the measurement may be performed or reported during a period configured or indicated for the first NES state. In method 800, the signaling associated with activating the first NES state may indicate at least one of the following: activation of the first NES state, when the first NES state is to be activated, or the period during which the first NES state may be activated. In method 800, the signaling associated with activating the first NES state may include a conditional handover (CHO) configuration or reconfiguration associated with the first NES state.

[0250] Although the features and elements have been described above in particular combinations, one of ordinary skill in the art will understand that each feature or element can be used separately or in any combination with other features and elements. In addition, the methods described herein can be implemented in a computer program, software, or firmware incorporated into a computer-readable medium for execution by a computer or processor. Examples of computer-readable media include electronic signals (transmitted via wired or wireless connections) and computer-readable storage media. Examples of computer-readable storage media include, but are not limited to, read-only memory (ROM), random access memory (RAM), registers, cache memory, semiconductor memory devices, magnetic media such as internal hard disks and removable disks, magneto-optical media, and optical media such as CD-ROM disks and digital versatile disks (DVDs). A processor associated with the software can be used to implement a radio frequency transceiver for a WTRU, UE, terminal, base station, RNC, or any host computer.

Claims

1. A method performed in a wireless transmit / receive unit (WTRU), the method comprising: Receiving configuration information indicating one or more measurement configurations, wherein each of the one or more measurement configurations includes NES status information indicating one or more network energy saving (NES) statuses to which the measurement configuration applies; Receiving signaling associated with activating a first NES status of the indicated one or more NES statuses; Determining, based on the received configuration information, a measurement configuration applicable to the first NES status; Performing one or more measurements using the determined measurement configuration; And Reporting the one or more measurements.

2. The method of claim 1, wherein the measurements are performed during a measurement time period configured for the first NES status.

3. The method of any one of claims 1 to 2, wherein the measurements are reported during a reporting time period configured for the first NES status.

4. The method of any one of claims 1 to 3, wherein the signaling associated with activating the first NES status indicates at least one selected from the group consisting of: activation of the first NES status, when the first NES status is to be activated, and an activation time period during which the first NES status can be activated.

5. The method of any one of claims 1 to 4, wherein the signaling associated with activating the first NES status includes a conditional handover (CHO) configuration associated with the first NES status.

6. The method of any one of claims 1 to 5, wherein the signaling associated with activating the first NES status includes a conditional handover (CHO) reconfiguration associated with the first NES status.

7. The method according to any one of claims 1 to 6, further comprising: Receiving signaling associated with activating a second NES status of the indicated one or more NES statuses.

8. The method according to any one of claims 1 to 7, further comprising: Deactivating the first NES status.

9. The method according to any one of claims 1 to 8, further comprising: Utilizing one or more measurement configurations not associated with any NES status.

10. The method of any one of claims 1 to 9, wherein the one or more measurements include at least one measurement of a neighboring cell.

11. A wireless transmit / receive unit (WTRU) comprising: A processor; And A transceiver communicatively coupled to the processor, The processor and the transceiver are operative to: Receive configuration information indicating one or more measurement configurations, wherein each of the one or more measurement configurations includes NES status information indicating one or more network energy saving (NES) statuses to which the measurement configuration applies; Receive signaling associated with activating a first NES status of the indicated one or more NES statuses; Determine, based on the received configuration information, a measurement configuration applicable to the first NES status; Perform one or more measurements using the determined measurement configuration; And Report the one or more measurements.

12. The WTRU of claim 11, wherein the measurements are performed during a measurement time period configured for the first NES status.

13. The WTRU according to claim 11 or 12, wherein the measurement is reported during a reporting period configured for the first NES state.

14. The WTRU according to any one of claims 11 to 13, wherein the signaling associated with activating the first NES state indicates at least one selected from the group consisting of: activation of the first NES state, when the first NES state is to be activated, and an activation period during which the first NES state can be activated.

15. The WTRU according to any one of claims 11 to 14, wherein the signaling associated with activating the first NES state includes a conditional handover (CHO) configuration associated with the first NES state.

16. The WTRU according to any one of claims 11 to 15, wherein the signaling associated with activating the first NES state includes a conditional handover (CHO) reconfiguration associated with the first NES state.

17. The WTRU according to any one of claims 11 to 16, wherein the processor and the transceiver are further configured to: receive signaling associated with activating a second NES state among the indicated one or more NES states.

18. The WTRU according to any one of claims 11 to 17, wherein the processor and the transceiver are further configured to: deactivate the first NES state.

19. The WTRU according to any one of claims 11 to 18, wherein the processor and the transceiver are further configured to: utilize one or more measurement configurations not associated with any NES state.

20. The WTRU according to any one of claims 11 to 19, wherein the one or more measurements include at least one measurement of a neighboring cell.

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