Timing advance update for non-serving cells

Abstract

Various aspects of the present disclosure generally relate to wireless communications. In some aspects, a user equipment (UE) may receive or determine information indicating a timing advance of a non-serving cell for the UE, and perform inter-cell mobility operations based at least in part on the timing advance of the non-serving cell for the UE. Many other aspects are provided.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This patent application claims priority to U.S. Provisional Patent Application No. 62 / 959,780, filed on January 10, 2020, and entitled “Timing Advance Update for Non-Service Cells,” and U.S. Non-Provisional Patent Application No. 17 / 114,768, filed on December 8, 2020, and entitled “Timing Advance Update for Non-Service Cells,” which are hereby expressly incorporated herein by reference. Technical Field

[0003] Aspects of the present disclosure generally relate to wireless communications and techniques and apparatus for timing advance (TA) updates for non-serving cells. Background Art

[0004] Wireless communication systems are widely used to provide various telecommunication services, such as telephony, video, data, messaging, and broadcast. Typical wireless communication systems may employ multiple access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc.). Examples of such multiple access technologies include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single carrier frequency division multiple access (SC-FDMA) systems, time division synchronous code division multiple access (TD-SCDMA) systems, and long term evolution (LTE). LTE / LTE-Advanced is a set of enhancements to the Universal Mobile Telecommunications System (UMTS) mobile standard promulgated by the 3rd Generation Partnership Project (3GPP).

[0005] A wireless communication network may include multiple base stations (BS) that can support communication of multiple user equipments (UEs). User equipments (UEs) may communicate with base stations (BSs) via downlinks and uplinks. Downlinks (or forward links) refer to the communication link from a BS to a UE, while uplinks (or reverse links) refer to the communication link from a UE to a BS. As will be described in more detail herein, a BS may be referred to as a Node B, gNB, access point (AP), radio head unit, transmit receive point (TRP), new radio (NR) BS, 5G Node B, etc.

[0006] The above-mentioned multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user devices to communicate at municipal, national, regional and even global levels. New Radio (NR), also known as 5G, is a set of enhancements to the LTE mobile standard promulgated by the Third Generation Partnership Project (3GPP). NR is designed to better support mobile broadband Internet access by improving spectrum efficiency, reducing costs, improving services, utilizing new spectrum and better integrating with other open standards, which use orthogonal frequency division multiplexing (OFDM) (CP-OFDM) with cyclic prefix (CP) on the downlink (DL), CP-OFDM and / or SC-FDM (e.g., also known as discrete Fourier transform spread OFDM (DFT-s-OFDM)) on the uplink (UL) and support beamforming, multiple input multiple output (MIMO) antenna technology and carrier aggregation. However, as the demand for mobile broadband access continues to increase, there is a need for further improvements in LTE and NR technologies. Preferably, these improvements should be applicable to other multiple access technologies and telecommunication standards that adopt these technologies. Summary of the invention

[0007] In some aspects, a wireless communication method performed by a user equipment (UE) may include: receiving or determining information indicating a timing advance for a non-serving cell for the UE, and performing inter-cell mobility operations based at least in part on the timing advance for the non-serving cell for the UE.

[0008]

[0011] In some aspects, a method of wireless communication performed by a base station may include determining information indicating a timing advance for a non-serving cell of a UE, and sending the information indicating the timing advance to the UE.

[0009] In some aspects, a UE for wireless communication may include a memory and one or more processors operably coupled to the memory. The memory and the one or more processors may be configured to receive or determine information indicating a timing advance for a non-serving cell for the UE, and perform inter-cell mobility operations based at least in part on the timing advance for the non-serving cell for the UE.

[0010] In some aspects, a base station for wireless communication may include a memory and one or more processors operably coupled to the memory. The memory and the one or more processors may be configured to determine information indicating a timing advance for a non-serving cell for a UE and send the information indicating the timing advance to the UE.

[0011] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. When executed by one or more processors of a UE, the one or more instructions may cause the one or more processors to: receive or determine information indicating a timing advance of a non-serving cell for the UE, and perform inter-cell mobility operations based at least in part on the timing advance of the non-serving cell for the UE.

[0012] In some aspects, a non-transitory computer-readable medium may store one or more instructions for wireless communication. When executed by one or more processors of a base station, the one or more instructions may cause the one or more processors to: determine information indicating a timing advance for a non-serving cell for a UE, and send the information indicating the timing advance to the UE.

[0013] In some aspects, an apparatus for wireless communication may include components for receiving or determining information indicating a timing advance of a non-serving cell for a UE and components for performing inter-cell mobility operations based at least in part on the timing advance of the non-serving cell for the apparatus.

[0014]

[0011] In some aspects, an apparatus for wireless communication may include a component for determining information indicating a timing advance of a non-serving cell for a UE and a component for sending the information indicating the timing advance to the UE.

[0015] Aspects generally include methods, apparatus, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, wireless communication devices, and / or processing systems substantially as substantially described herein with reference to and as illustrated in the accompanying drawings.

[0016] The features and technical advantages of examples according to the present disclosure have been outlined quite broadly above so that the following detailed description may be better understood. Additional features and advantages will be described below. The disclosed concepts and specific examples may be easily used as a basis for modifying or designing other structures for implementing the same purpose of the present disclosure. Such equivalent structures do not depart from the scope of the appended claims. The features of the concepts disclosed herein, their organization and methods of operation, and associated advantages will be better understood from the following description when considered in conjunction with the accompanying drawings. Each of the accompanying drawings is provided for the purpose of illustration and description and not as a definition of limitations of the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order that the above-mentioned features of the present disclosure may be understood in detail, a more specific description briefly summarized above may be obtained by reference to a number of aspects, some of which are illustrated in the accompanying drawings. However, it should be noted that the accompanying drawings illustrate only certain typical aspects of the present disclosure and therefore should not be considered as limiting the scope thereof, as the specification may admit of other equivalent aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0018] Figure 1 is a block diagram conceptually illustrating an example of a wireless communication network in accordance with various aspects of the present disclosure.

[0019] Figure 2 is a block diagram conceptually illustrating an example of a base station communicating with a UE in a wireless communication network according to various aspects of the present disclosure.

[0020] Figure 3 is a diagram illustrating an example of determining a timing advance for a non-serving cell using a random access channel procedure in accordance with various aspects of the present disclosure.

[0021] Figure 4 is a diagram illustrating an example of using a reference signal procedure to determine timing advance for a non-serving cell in accordance with various aspects of the present disclosure.

[0022] Figure 5 is a diagram illustrating an example of determining timing advance for a non-serving cell using a synchronization signal block procedure in accordance with various aspects of the present disclosure.

[0023] Figure 6 is a diagram illustrating an example process performed, for example, by a user device, according to various aspects of the present disclosure.

[0024] Figure 7 is a diagram illustrating example processes performed, for example, by a base station according to various aspects of the present disclosure. DETAILED DESCRIPTION

[0025] The various aspects of the present disclosure will be described more fully below with reference to the accompanying drawings. However, the present disclosure can be embodied in many different forms and should not be construed as being limited to any specific structure or function presented in the present disclosure. On the contrary, these aspects are provided so that the present disclosure will be thorough and complete, and the scope of the present disclosure will be fully conveyed to those skilled in the art. Based on the teachings herein, it should be understood by those skilled in the art that the scope of the present disclosure is intended to cover any aspect of the present disclosure disclosed herein, whether it is implemented independently of any other aspect of the present disclosure or implemented in combination with any other aspect of the present disclosure. For example, any number of aspects set forth herein may be used to implement a device or practice method. In addition, the scope of the present disclosure is intended to cover such a device or method practiced using other structures, functionality, or structures and functionality other than the various aspects of the present disclosure set forth herein or other aspects of the present disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of the claims.

[0026] Several aspects of telecommunication systems will now be presented with reference to various devices and techniques. These devices and techniques will be described in the following detailed description and illustrated in the accompanying drawings by various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"). These elements may be implemented using hardware, software, or a combination thereof. Whether such elements are implemented as hardware or software depends on the specific application and the design constraints imposed on the overall system.

[0027] It should be noted that although terms generally associated with 5G or NR radio access technologies (RATs) may be used herein to describe various aspects, various aspects of the present disclosure may be applicable to other RATs, such as 3G RATs, 4G RATs, and / or RATs beyond 5G (e.g., 6G).

[0028] Figure 1 1 is a diagram illustrating a wireless network 100 in which various aspects of the present disclosure may be practiced. The wireless network 100 may be an LTE network or some other wireless network, such as a 5G or NR network. The wireless network 100 may include a plurality of BSs 110 (shown as BSs 110a, BSs 110b, BSs 110c, and BSs 110d) and other network entities. A BS is an entity that communicates with a user equipment (UE) and may also be referred to as a base station, NR BS, Node B, gNB, 5G Node B (NB), access point, transmit receive point (TRP), etc. Each BS may provide communication coverage for a particular geographic area. In 3GPP, the term "cell" may refer to a coverage area of ​​a BS and / or a BS subsystem serving the coverage area, depending on the context in which the term is used.

[0029] A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and / or another type of cell. A macro cell may cover a relatively large geographic area (e.g., a radius of several kilometers) and may allow unrestricted access to UEs with service subscriptions. A pico cell may cover a relatively small geographic area and may allow unrestricted access to UEs with service subscriptions. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access to UEs associated with the femto cell (e.g., UEs in a closed subscriber group (CSG)). A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In Figure 1 In the example shown in , BS 110a can be a macro BS for macro cell 102a, BS 110b can be a pico BS for pico cell 102b, and BS 110c can be a femto BS for femto cell 102c. The BS can support one or more (e.g., three) cells. The terms "eNB", "base station", "NR BS", "gNB", "TRP", "AP", "Node B", "5G NB" and "cell" may be used interchangeably herein.

[0030] In some aspects, the cell may not necessarily be fixed, and the geographic area of ​​the cell may move depending on the location of the mobile BS. In some aspects, the BSs may be interconnected with each other and / or with one or more other BSs or network nodes (not shown) in the wireless network 100 through various types of backhaul interfaces (such as direct physical connections, virtual networks, etc.) using any suitable transport network.

[0031] The wireless network 100 may also include a relay station. A relay station is an entity that can receive transmissions of data from an upstream station (e.g., a BS or a UE) and send transmissions of data to a downstream station (e.g., a UE or a BS). A relay station may also be a UE that is capable of relaying transmissions for other UEs. Figure 1 In the example shown in FIG. 1 , a relay station 110 d may communicate with a macro BS 110 a and a UE 120 d to facilitate communication between the BS 110 a and the UE 120 d. A relay station may also be referred to as a relay BS, a relay base station, a relay, or the like.

[0032] The wireless network 100 may be a heterogeneous network including different types of BSs, such as macro BSs, pico BSs, femto BSs, relay BSs, etc. These different types of BSs may have different transmit power levels, different coverage areas, and different effects on interference in the wireless network 100. For example, a macro BS may have a high transmit power level (e.g., 5 to 40 watts), while a pico BS, a femto BS, and a relay BS may have a lower transmit power level (e.g., 0.1 to 2 watts).

[0033] A network controller 130 may be coupled to a set of BSs and may provide coordination and control for these BSs. The network controller 130 may communicate with the BSs via a backhaul. The BSs may also communicate with each other directly or indirectly, for example, via a wireless or wired backhaul.

[0034] UE 120 (e.g., 120a, 120b, 120c) can be dispersed throughout the wireless network 100, and each UE can be fixed or mobile. UE can also be referred to as an access terminal, terminal, mobile station, subscriber unit, station, etc. UE can be a cellular phone (e.g., a smart phone), a personal digital assistant (PDA), a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, a medical device or equipment, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet)), an entertainment device (e.g., a music or video device or a satellite radio), a vehicle-mounted component or sensor, a smart meter / sensor, an industrial manufacturing device, a global positioning system device, or any other suitable device configured to communicate via a wireless or wired medium.

[0035] Some UEs may be considered as machine type communication (MTC) or evolved or enhanced machine type communication (eMTC) UEs. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc. that can communicate with a base station, another device (e.g., a remote device), or some other entity. For example, a wireless node may provide a connection to or to a network (e.g., a wide area network such as the Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered as Internet of Things (IoT) devices and / or may be implemented as NB-IoT (narrowband Internet of Things) devices. Some UEs may be considered as user premises equipment (CPE). UE 120 may be included inside a housing that houses components of UE 120 (such as a processor component, a memory component, etc.).

[0036] Typically, any number of wireless networks can be deployed in a given geographic area. Each wireless network can support a specific radio access technology (RAT) and can operate on one or more frequencies. RAT can also be referred to as radio technology, air interface, etc. Frequency can also be referred to as carrier, frequency channel, etc. Each frequency can support a single RAT in a given geographic area to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks can be deployed.

[0037] In some aspects, two or more UEs 120 (e.g., shown as UE 120a and UE 120e) may communicate directly (e.g., without using base station 110 as an intermediary to communicate with each other) using one or more sidelink channels. For example, UE 120 may communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which may include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, etc.), mesh networks, etc. In this case, UE 120 may perform scheduling operations, resource selection operations, and / or other operations performed by base station 110 as described elsewhere herein.

[0038] The devices of the wireless network 100 can communicate using an electromagnetic spectrum, which can be subdivided into various categories, frequency bands, channels, etc. based at least in part on frequency or wavelength. For example, the devices of the wireless network 100 can communicate using an operating frequency band having a first frequency range (FR1), which can be between 410 MHz and 7.125 GHz, and / or can communicate using an operating frequency band having a second frequency range (FR2), which can be between 24.25 GHz and 52.6 GHz. Frequencies between FR1 and FR2 are sometimes referred to as mid-band frequencies. Although a portion of FR1 is greater than 6 GHz, FR1 is often referred to as a "sub-6 GHz" band. Similarly, FR2 is often referred to as a "millimeter wave" band, although different from the extremely high frequency (EHF) band (30 GHz to 300 GHz) identified as a "millimeter wave" band by the International Telecommunication Union (ITU). Therefore, unless otherwise specifically stated, it should be understood that the terms "sub-6 GHz" and the like, if used herein, can broadly refer to frequencies less than 6 GHz, frequencies within FR1, and / or mid-band frequencies (e.g., greater than 7.125 GHz). Similarly, unless otherwise specifically stated, it should be understood that the terms "millimeter wave" and the like, if used herein, can broadly refer to frequencies within the EHF band, frequencies within FR2, and / or mid-band frequencies (e.g., less than 24.25 GHz). It is contemplated that the frequencies included in FR1 and FR2 can be modified, and the techniques described herein are applicable to those modified frequency ranges.

[0039] As indicated above, provide Figure 1 As an example. Other examples can be related to Figure 1 Different than described.

[0040] Figure 2 A block diagram shows a design 200 of a base station 110 and a UE 120, which may be Figure 1 Base station 110 may be equipped with T antennas 234a through 234t, and UE 120 may be equipped with R antennas 252a through 252r, where in general, T≥1 and R≥1.

[0041] At the base station 110, the transmit processor 220 may receive data for one or more UEs from the data source 212, select one or more modulation and coding schemes (MCS) for each UE based at least in part on a channel quality indicator (CQI) received from the UE, process (e.g., encode and modulate) the data for each UE based at least in part on the MCS selected for the UE, and provide data symbols for all UEs. The transmit processor 220 may also process system information (e.g., for semi-static resource partitioning information (SRPI), etc.) and control information (e.g., CQI requests, grants, upper layer signaling, etc.), and provide overhead symbols and control symbols. The transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signals (CRS)) and synchronization signals (e.g., primary synchronization signals (PSS) and secondary synchronization signals (SSS)). If applicable, the transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on ​​data symbols, control symbols, overhead symbols, and / or reference symbols, and may provide T output symbol streams to T modulators (MOD) 232a to 232t. Each modulator 232 may process a corresponding output symbol stream (e.g., for OFDM, etc.) to obtain an output sample stream. Each modulator 232 may further process (e.g., convert to analog, amplify, filter, and up-convert) the output sample stream to obtain a downlink signal. The T downlink signals from modulators 232a to 232t may be transmitted via T antennas 234a to 234t, respectively. According to various aspects described in more detail below, position coding may be used to generate synchronization signals to convey additional information.

[0042] At the UE 120, antennas 252a to 252r may receive downlink signals from the base station 110 and / or other base stations, and may provide received signals to demodulators (DEMODs) 254a to 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) the received signal to obtain input samples. Each demodulator 254 may further process the input samples (e.g., for OFDM, etc.) to obtain received symbols. A MIMO detector 256 may obtain received symbols from all R demodulators 254a to 254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide decoded data for the UE 120 to a data sink 260, and provide decoded control information and system information to a controller / processor 280. The channel processor may determine reference signal received power (RSRP), received signal strength indicator (RSSI), reference signal received quality (RSRQ), channel quality indicator (CQI), etc. In some aspects, one or more components of UE 120 may be included in a housing.

[0043] On the uplink, at the UE 120, a transmit processor 264 may receive and process data from a data source 262 and control information from a controller / processor 280 (e.g., for reports including RSRP, RSSI, RSRQ, CQI, etc.). The transmit processor 264 may also generate reference symbols for one or more reference signals. If appropriate, the symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 (if applicable), further processed by modulators 254a through 254r (e.g., for DFT-s-OFDM, CP-OFDM, etc.), and transmitted to the base station 110. At the base station 110, uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the demodulator 232, detected by the MIMO detector 236 (if applicable), and further processed by the receive processor 238 to obtain decoded data and control information transmitted by the UE 120. The receive processor 238 may provide decoded data to a data sink 239 and decoded control information to a controller / processor 240. The base station 110 may include a communication unit 244 and communicate with the network controller 130 via the communication unit 244. The network controller 130 may include a communication unit 294, a controller / processor 290, and a memory 292.

[0044] The controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or Figure 2Any other component of may perform one or more techniques associated with timing advance updates for non-serving cells, as described in more detail elsewhere herein. For example, controller / processor 240 of base station 110, controller / processor 280 of UE 120, and / or Figure 2 Any other component of may execute or direct e.g. Figure 6 The process of 600 Figure 7 The operations of process 700 and / or other processes as described herein. Memories 242 and 282 may store data and program codes for base station 110 and UE 120, respectively. In some aspects, memory 242 and / or memory 282 may include a non-transitory computer-readable medium storing one or more instructions for wireless communication. For example, when executed by one or more processors of base station 110 and / or UE 120, the one or more instructions may perform or direct, for example, Figure 6 The process of 600 Figure 7 The operations of process 700 and / or other processes as described herein. Scheduler 246 may schedule UEs for data transmission on the downlink and / or uplink.

[0045] In some aspects, UE 120 may include: a component for receiving or determining information indicating a timing advance of a non-serving cell for the UE; a component for performing an inter-cell mobility operation based at least in part on the timing advance of the non-serving cell for the UE; a component for receiving signaling indicating that the non-serving cell belongs to a timing advance group; a component for receiving a corresponding signal from the non-serving cell and the serving cell, wherein determining the information indicating the timing advance is based at least in part on measuring a received timing difference between the corresponding signals; a component for sending information indicating the received timing difference to at least one of the serving cell or the non-serving cell; and the like. In some aspects, such components may include combining Figure 2 One or more components of UE 120 are depicted, such as controller / processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, etc.

[0046] In some aspects, the base station 110 may include: a component for determining information indicating a timing advance of a non-serving cell for a UE; a component for sending information indicating the timing advance to the UE; a component for sending signaling indicating that the non-serving cell belongs to a timing advance group; a component for performing layer 1 or layer 2 based inter-cell mobility operations based at least in part on the timing advance of the non-serving cell for the UE; a component for sending a physical downlink control channel command to the UE to trigger the transmission of a RACH preamble, wherein the timing advance is based at least in part on a time difference between the RACH preamble and the physical downlink control channel command; a component for scheduling an SRS to be sent to a serving cell or a non-serving cell; a component for triggering the SRS using downlink control information; and the like. In some aspects, such components may include in conjunction with Figure 2 One or more components of base station 110 are depicted, such as antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, and the like.

[0047] As indicated above, provide Figure 2 As an example. Other examples can be related to Figure 2 Different than described.

[0048] The UE may perform inter-cell mobility operations to select a candidate cell (also referred to as a selected cell) for communication between the UE and the network. For example, in a dual connectivity operation, the UE may select a set of candidate cells, and may select one or more primary cells (PCells), secondary cells (SCells), primary secondary cells (PSCells), and / or secondary primary cells or dedicated cells (SPCells). PCells and SCells may be referred to as serving cells. "Non-serving cells" may refer to neighboring cells or candidate cells. In some aspects, "SPCell" may refer to a PCell of a primary cell group or a PSCell of a secondary cell group, or to a PCell.

[0049] It may be beneficial to reduce latency and higher layer overhead associated with inter-cell mobility. One way to reduce latency and higher layer overhead is to perform inter-cell mobility operations based on layer 1 or layer 2, where the mobility operations are handled by the physical layer or media access control layer of the UE. However, the reduced latency of inter-cell mobility operations based on layer 1 or layer 2 may mean that the UE experiences delays in inter-cell mobility based at least in part on not determining a timing advance for non-serving cells. For example, the UE may receive information indicating a timing advance for only a serving cell. Therefore, the UE may experience delays in initiating communication with a newly configured serving cell until the UE receives a timing advance command from the newly configured serving cell, which consumes computing resources of the UE and the newly configured serving cell and increases latency.

[0050] Some techniques and apparatus described herein provide for determining or signaling a timing advance (TA) for a non-serving cell (e.g., a candidate cell or a neighboring cell). For example, the TA may be signaled to the UE by the UE's serving cell, or may be determined by the UE. In some aspects, the serving cell may update the TA of a TA group (TAG), which may update the TA of each cell (e.g., a serving cell or a non-serving cell) included in the TAG. The TA may be determined based at least in part on a random access channel (RACH) process on the non-serving cell, a reference signal (e.g., a sounding reference signal (SRS), etc.) sent by the UE, or a signal sent by the serving cell and / or the non-serving cell. In this way, the UE may determine the timing advance for the non-serving cell, which reduces the delay associated with inter-cell mobility operations including the non-serving cell, and once the non-serving cell is configured as a serving cell, computational resources associated with determining the timing advance are saved.

[0051] Figure 3 1 is a diagram illustrating an example 300 of determining timing advance for a non-serving cell using a RACH procedure in accordance with various aspects of the present disclosure. As shown, example 300 includes a UE 120, a serving cell (e.g., provided by BS 110), and a non-serving cell (e.g., provided by BS 110). The serving cell and the non-serving cell may be provided by the same BS 110 or different BSs 110. Figures 3 to 5 In the figure, the dashed boxes generally indicate actions that can be performed on the serving cell or non-serving cell. As mentioned above, "cell", "base station" and "gNB" are used interchangeably in this document. Therefore, references to transmissions or determinations of a cell should be understood to also refer to transmissions or determinations of a base station associated with a cell or a gNB associated with a cell.

[0052] like Figure 3As shown in FIG. 1 and by reference numeral 310, the serving cell may send a physical downlink control channel (PDCCH) order to UE 120. The PDCCH order may trigger the transmission of a RACH preamble on a non-serving cell by UE 120. For example, the PDCCH order may initiate a physical RACH (PRACH) procedure on the non-serving cell.

[0053] As indicated by reference numeral 320, UE 120 may transmit a RACH preamble on a non-serving cell based at least in part on a PDCCH order. UE 120 may transmit the RACH preamble so that a BS 110 associated with a serving cell and / or a BS 110 associated with a non-serving cell may determine a timing advance of UE 120 based at least in part on a transmission time or a RACH resource associated with the RACH preamble and a propagation delay associated with the RACH preamble.

[0054] As shown in reference numerals 330 and 340, the serving cell and / or the non-serving cell may determine the timing advance based at least in part on the RACH preamble. For example, the serving cell and / or the non-serving cell may determine the timing advance based at least in part on the transmission time or the RACH resource and the propagation delay. As shown in reference numerals 350 and 360, the UE 120 may receive a RACH response on a serving cell (e.g., a PCell, SCell, or SPCell) and / or a non-serving cell. For example, the RACH response may identify the timing advance. In some aspects, another form of signaling (such as medium access control (MAC) signaling, etc.) may be used to provide the timing advance to the UE 120.

[0055] In some aspects, the non-serving cells involved in the timing advance may be identified by a physical cell identifier (PCI) of the non-serving cell. In some aspects, the non-serving cells (e.g., each non-serving cell) may be associated with a corresponding TAG identifier, which may be signaled to the UE 120 using radio resource control (RRC) signaling, MAC control element (MAC-CE), downlink control information (DCI), etc. The TA control MAC-CE may update the timing advance of all cells of the TAG, which may include non-serving cells or corresponding PCIs.

[0056] As indicated by reference numeral 370, UE 120 may perform inter-cell mobility operations (e.g., inter-cell mobility operations based on layer 1 or layer 2) based on the timing advance. For example, UE 120 may add one or more non-serving cells as serving cells or candidate cells, may store the timing advances of the non-serving cells for future use, etc. In this way, UE 120 may determine the timing advances of the non-serving cells without connecting to the non-serving cells, which saves computational resources and reduces delays associated with connecting to the non-serving cells and subsequently determining the timing advances.

[0057] As indicated above, provide Figure 3 As an example. Other examples can be related to Figure 3 Different than described.

[0058] Figure 4 4 is a diagram illustrating an example 400 of using a reference signal (RS) process to determine timing advance for a non-serving cell in accordance with various aspects of the present disclosure. As shown, Figure 4 Including combination Figure 3 UE 120, serving cell, and non-serving cell are described in more detail.

[0059] like Figure 4 As shown in FIG. 1 and by reference numeral 410, UE 120 may receive DCI from a serving cell. The DCI may trigger UE 120 to send RS, such as SRS. For example, the DCI may schedule the UE to send SRS to one or more serving cells and / or one or more non-serving cells. As shown by reference numerals 420 and 430, UE 120 may send SRS to the serving cell and the non-serving cell.

[0060] As indicated by reference numerals 440 and 450, the serving cell and / or the non-serving cell may determine a timing advance for the non-serving cell. For example, the serving cell and / or the non-serving cell may determine the timing advance based at least in part on a reception timing difference of an SRS at the serving cell and the non-serving cell. Thus, as indicated by reference numerals 460 and 470, the serving cell and / or the non-serving cell may signal the timing advance or the reception timing difference to the UE 120. In some aspects, the serving cell and / or the non-serving cell may signal the timing advance difference to the UE 120, which may indicate a difference between the timing advance of the serving cell and the timing advance of the non-serving cell. As indicated by reference numeral 480, the UE 120 may perform inter-cell mobility operations based on the timing advance, such as in conjunction with Figure 3 In this way, UE 120 can determine the timing advance of a non-serving cell without connecting to the non-serving cell, which saves computational resources and reduces the delay associated with connecting to the non-serving cell and then determining the timing advance.

[0061] In some aspects, UE 120 may send SRS to two or more non-serving cells. For example, UE 120 may send SRS to a non-serving cell with a known timing advance relative to the UE and to a non-serving cell for which a timing advance is to be determined. One or more of these non-serving cells may determine a timing advance, a timing advance difference, or a received timing difference, and may signal the timing advance, the timing advance difference, or the received timing difference to UE 120.

[0062] As indicated above, provide Figure 4 As an example. Other examples can be related to Figure 4 Different than described.

[0063] Figure 5 is a diagram illustrating an example 500 of determining timing advance for a non-serving cell using a synchronization signal block (SSB) procedure in accordance with various aspects of the present disclosure. As shown, Figure 5 Including combination Figure 3 UE 120, serving cell, and non-serving cell are described in more detail.

[0064] like Figure 5 As shown in and by reference numerals 510 and 520, UE 120 may receive SSBs from a serving cell and a non-serving cell. For example, UE 120 may receive corresponding signals from the serving cell and the non-serving cell. As shown in reference numeral 530, UE 120 may determine and report a receive timing difference between a serving cell and a non-serving cell based at least in part on the SSB. For example, UE 120 may determine a propagation delay difference between a serving cell and a non-serving cell based at least in part on the corresponding signal. UE 120 may determine and / or report a propagation delay difference or a timing advance or a timing advance difference based at least in part on the propagation delay difference. The propagation delay difference may be similar to the receive timing difference. In some aspects, UE 120 may receive information indicating a timing advance for a non-serving cell from a serving cell and / or a non-serving cell (not shown). For example, a serving cell and / or a non-serving cell may determine a timing advance based at least in part on the receive timing difference, and may provide information indicating the timing advance to UE 120. As shown in reference numeral 540, UE 120 may perform inter-cell mobility operations based on the timing advance or the receive timing difference, such as in combination with Figure 3 and 4 Describe in more detail.

[0065] As indicated above, provide Figure 5 As an example. Other examples can be related to Figure 5 Different than described.

[0066] Figure 6is a diagram illustrating an example process 600 performed, for example, by a UE in accordance with various aspects of the present disclosure. Example process 600 is an example of a UE (eg, UE 120, etc.) performing operations associated with determining a timing advance for a non-serving cell.

[0067] like Figure 6 , in some aspects, process 600 may include receiving or determining information indicating a timing advance for a non-serving cell for the UE (block 610). For example, as described above, the UE (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, etc.) may receive or determine information indicating a timing advance for a non-serving cell for the UE.

[0068] like Figure 6 As further shown in FIG. 6 , in some aspects, process 600 may include performing inter-cell mobility operations based at least in part on a timing advance of a non-serving cell for the UE (block 620). For example, as described above, the UE (e.g., using controller / processor 280, transmit processor 264, TX MIMO processor 266, MOD 254, antenna 252, etc.) may perform inter-cell mobility operations based at least in part on a timing advance of a non-serving cell for the UE.

[0069] Process 600 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in combination with one or more other processes described elsewhere herein.

[0070] In a first aspect, the inter-cell mobility operation is a layer 1 or layer 2 based inter-cell mobility operation.

[0071] In a second aspect, alone or in combination with the first aspect, the non-serving cell is a neighboring cell of the UE.

[0072] In a third aspect, alone or in combination with one or more of the first and second aspects, the non-serving cell is identified by a physical cell identifier of the non-serving cell.

[0073] In a fourth aspect, alone or in combination with one or more of the first to third aspects, the timing advance is associated with a timing advance group to which the non-serving cell belongs.

[0074] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, process 600 includes receiving signaling indicating that a non-serving cell belongs to a timing advance group.

[0075] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, the information indicating the timing advance indicates a physical cell identifier of a non-serving cell or a timing advance group identifier of a timing advance group to which the non-serving cell belongs.

[0076] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, a timing advance group identifier is signaled using at least one of: radio resource control signaling, medium access control control element, or downlink control information.

[0077] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, the timing advance is used for all cells in a timing advance group.

[0078] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the timing advance is based at least in part on a random access channel (RACH) preamble sent by the UE to a non-serving cell.

[0079] In a tenth aspect, alone or in combination with one or more of the first to ninth aspects, the RACH preamble is triggered by a physical downlink control channel command received from a serving cell of the UE or from a non-serving cell.

[0080] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, information indicating a timing advance is received in a RACH response.

[0081] In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, the timing advance is at least partially based on a sounding reference signal (SRS) sent by the UE to at least one of a serving cell or a non-serving cell.

[0082] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, the SRS is scheduled by a serving cell.

[0083] In a fourteenth aspect, alone or in combination with one or more of the first to thirteenth aspects, the SRS is triggered by downlink control information.

[0084] In a fifteenth aspect, either alone or in combination with one or more of the first to fourteenth aspects, process 600 includes receiving respective signals from a non-serving cell and a serving cell, wherein determining information indicating a timing advance is based at least in part on measuring a receive timing difference between the respective signals.

[0085] In a sixteenth aspect, alone or in combination with one or more of the first to fifteenth aspects, process 600 includes sending information indicative of the receive timing difference to at least one of a serving cell or a non-serving cell.

[0086] In a seventeenth aspect, either alone or in combination with one or more of the first to sixteenth aspects, the corresponding signal comprises a synchronization signal block.

[0087] although Figure 6 Example blocks of process 600 are shown, but in some aspects, process 600 may include Figure 6 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIG. Additionally or alternatively, two or more blocks of process 600 may be performed in parallel.

[0088] Figure 7 is a diagram illustrating an example process 700, performed, for example, by a base station, in accordance with various aspects of the present disclosure. Example process 700 is an example of operations performed by a base station (eg, BS 110, etc.) associated with determining a timing advance for a non-serving cell.

[0089] like Figure 7 , in some aspects, process 700 may include determining information indicating a timing advance for a non-serving cell of a user equipment (UE) (block 710). For example, as described above, a base station (e.g., using antenna 234, DEMOD 232, MIMO detector 236, receive processor 238, controller / processor 240, etc.) may determine information indicating a timing advance for a non-serving cell of the UE.

[0090] like Figure 7 As further shown in FIG. 7 , in some aspects, process 700 may include sending information indicating a timing advance to the UE (block 720). For example, as described above, the base station (e.g., using controller / processor 240, transmit processor 220, TX MIMO processor 230, MOD 232, antenna 234, etc.) may send information indicating a timing advance to the UE.

[0091] Process 700 may include additional aspects, such as any single aspect or any combination of aspects described below and / or in combination with one or more other processes described elsewhere herein.

[0092] In a first aspect, process 700 includes performing layer 1 or layer 2 based inter-cell mobility operations based at least in part on a timing advance of a non-serving cell for a UE.

[0093] In a second aspect, alone or in combination with the first aspect, the non-serving cell is a neighboring cell of the UE.

[0094] In a third aspect, alone or in combination with one or more of the first and second aspects, the non-serving cell is identified by a physical cell identifier of the non-serving cell.

[0095] In a fourth aspect, alone or in combination with one or more of the first to third aspects, the timing advance is associated with a timing advance group to which the non-serving cell belongs.

[0096] In a fifth aspect, alone or in combination with one or more of the first to fourth aspects, process 700 includes sending signaling indicating that the non-serving cell belongs to a timing advance group.

[0097] In a sixth aspect, alone or in combination with one or more of the first to fifth aspects, the information indicating the timing advance indicates a physical cell identifier of a non-serving cell or a timing advance group identifier of a timing advance group to which the non-serving cell belongs.

[0098] In a seventh aspect, alone or in combination with one or more of the first to sixth aspects, a timing advance group identifier is signaled using at least one of: radio resource control signaling, medium access control control element, or downlink control information.

[0099] In an eighth aspect, alone or in combination with one or more of the first to seventh aspects, the timing advance is used for all cells in a timing advance group.

[0100] In a ninth aspect, alone or in combination with one or more of the first to eighth aspects, the timing advance is based at least in part on a RACH preamble sent by the UE to the non-serving cell.

[0101] In a tenth aspect, either alone or in combination with one or more of the first to ninth aspects, process 700 comprises sending a physical downlink control channel command to a UE to trigger the sending of a RACH preamble, wherein the timing advance is based at least in part on a time difference between the RACH preamble and the physical downlink control channel command.

[0102] In an eleventh aspect, alone or in combination with one or more of the first to tenth aspects, information indicating a timing advance is sent in a RACH response.

[0103] In a twelfth aspect, alone or in combination with one or more of the first to eleventh aspects, the timing advance is based at least in part on receiving a sounding reference signal (SRS) from the UE.

[0104] In a thirteenth aspect, alone or in combination with one or more of the first to twelfth aspects, process 700 includes scheduling an SRS to be transmitted to a serving cell or a non-serving cell.

[0105] In a fourteenth aspect, alone or in combination with one or more of the first to thirteenth aspects, process 700 includes triggering SRS using downlink control information.

[0106] In a fifteenth aspect, alone or in combination with one or more of the first to fourteenth aspects, determining the information indicative of the timing advance is based at least in part on information received from the UE.

[0107] In a sixteenth aspect, either alone or in combination with one or more of the first to fifteenth aspects, the information received from the UE is based at least in part on a reception timing difference between a signal sent by a base station on a serving cell and a signal sent by a non-serving cell.

[0108] In a seventeenth aspect, either alone or in combination with one or more of the first to sixteenth aspects, the corresponding signal comprises a synchronization signal block.

[0109] although Figure 7 Example blocks of process 700 are shown, but in some aspects, process 700 may include Figure 7 Additional blocks, fewer blocks, different blocks, or differently arranged blocks than those depicted in FIG. Additionally or alternatively, two or more blocks of process 700 may be performed in parallel.

[0110] The following provides an overview of various aspects of the present disclosure:

[0111] Aspect 1: A wireless communication method performed by a user equipment (UE), comprising: receiving or determining information indicating a timing advance of a non-serving cell for the UE; and performing an inter-cell mobility operation based at least in part on the timing advance of the non-serving cell for the UE.

[0112] Aspect 2: The method according to aspect 1, wherein the inter-cell mobility operation is based on layer 1 or layer 2 inter-cell mobility operation.

[0113] Aspect 3: The method according to any one of aspects 1 to 2, wherein the non-serving cell is a neighboring cell of the UE.

[0114] Aspect 4: The method according to any one of aspects 1 to 3, wherein the non-serving cell is identified by a physical cell identifier of the non-serving cell.

[0115] Aspect 5: The method according to any one of aspects 1 to 4, wherein the timing advance is associated with a timing advance group to which the non-serving cell belongs.

[0116] Aspect 6: The method according to aspect 5 further comprises: receiving signaling indicating that the non-serving cell belongs to a timing advance group.

[0117] Aspect 7: The method according to any one of aspects 1 to 6, wherein the information indicating the timing advance indicates a physical cell identifier of the non-serving cell or a timing advance group identifier of a timing advance group to which the non-serving cell belongs.

[0118] Aspect 8: The method according to aspect 7, wherein the timing advance group identifier is signaled using at least one of the following: radio resource control signaling, medium access control control element, or downlink control information.

[0119] Aspect 9: The method according to aspect 7, wherein the timing advance is for all cells of the timing advance group.

[0120] Aspect 10: The method according to any one of aspects 1 to 9, wherein the timing advance is based at least in part on a random access channel (RACH) preamble sent by the UE to the non-serving cell.

[0121] Aspect 11: The method according to aspect 10, wherein the RACH preamble is triggered by a physical downlink control channel command received from a serving cell of the UE or from a non-serving cell.

[0122] Aspect 12: The method according to aspect 10, wherein the information indicating the timing advance is received in a RACH response.

[0123] Aspect 13: The method according to any one of aspects 1 to 12, wherein the timing advance is based at least in part on a sounding reference signal (SRS) sent by the UE to at least one of a serving cell or a non-serving cell.

[0124] Aspect 14: The method according to Aspect 13, wherein the SRS is scheduled by a serving cell.

[0125] Aspect 15: The method according to Aspect 13, wherein the SRS is triggered by downlink control information.

[0126] Aspect 16: The method according to any one of aspects 1 to 15 further comprises: receiving corresponding signals from a non-serving cell and a serving cell, wherein determining the information indicating the timing advance is at least partially based on measuring a reception timing difference between the corresponding signals.

[0127] Aspect 17: The method according to Aspect 16 further comprises: sending information indicating the reception timing difference to at least one of the serving cell or the non-serving cell.

[0128] Aspect 18: The method according to Aspect 16, wherein the corresponding signal includes a synchronization signal block.

[0129] Aspect 19: A wireless communication method performed by a base station, comprising: determining information indicating a timing advance for a non-serving cell of a user equipment (UE); and sending the information indicating the timing advance to the UE.

[0130] Aspect 20: The method according to aspect 19 further comprises: performing layer 1 or layer 2 based inter-cell mobility operations based at least in part on a timing advance of a non-serving cell for the UE.

[0131] Aspect 21: The method according to any one of aspects 19 to 20, wherein the non-serving cell is a neighboring cell of the UE.

[0132] Aspect 22: The method according to any one of aspects 19 to 21, wherein the non-serving cell is identified by a physical cell identifier of the non-serving cell.

[0133] Aspect 23: The method according to any one of aspects 19 to 22, wherein the timing advance is associated with a timing advance group to which the non-serving cell belongs.

[0134] Aspect 24: The method according to Aspect 23 further comprises: sending signaling indicating that the non-serving cell belongs to a timing advance group.

[0135] Aspect 25: The method according to any one of aspects 19 to 24, wherein the information indicating the timing advance indicates a physical cell identifier of the non-serving cell or a timing advance group identifier of a timing advance group to which the non-serving cell belongs.

[0136] Aspect 26: The method according to aspect 25, wherein the timing advance group identifier is signaled using at least one of the following: radio resource control signaling, medium access control control element, or downlink control information.

[0137] Aspect 27: The method according to Aspect 25, wherein the timing advance is for all cells of the timing advance group.

[0138] Aspect 28: The method according to any one of aspects 19 to 27, wherein the timing advance is based at least in part on a random access channel (RACH) preamble sent by the UE to the non-serving cell.

[0139] Aspect 29: The method according to Aspect 28 further comprises: sending a physical downlink control channel command to the UE to trigger the sending of a RACH preamble code, wherein the timing advance is at least partially based on measuring the time difference between the RACH preamble code and the physical downlink control channel command.

[0140] Aspect 30: The method according to aspect 28, wherein the information indicating the timing advance is sent in a RACH response.

[0141] Aspect 31: The method according to any one of aspects 19 to 30, wherein the timing advance is based at least in part on receiving a sounding reference signal (SRS) from the UE.

[0142] Aspect 32: The method according to Aspect 31 further comprises: scheduling the SRS to be sent to the serving cell or the non-serving cell.

[0143] Aspect 33: The method according to Aspect 32 further comprises: using downlink control information to trigger SRS.

[0144] Aspect 34: The method according to any one of aspects 19 to 33, wherein determining the information indicative of the timing advance is based at least in part on information received from the UE.

[0145] Aspect 35: The method according to aspect 34, wherein the information received from the UE is based at least in part on a reception timing difference between a signal sent by the base station on a serving cell and a signal sent by a non-serving cell.

[0146] Aspect 36: The method according to Aspect 35, wherein the signal transmitted on the serving cell and the signal transmitted by the non-serving cell include a synchronization signal block.

[0147] Aspect 37: An apparatus for wireless communication at a device, comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to one or more of Aspects 1 to 36.

[0148] Aspect 38: A device for wireless communication, comprising a memory and one or more processors coupled to the memory, the memory and the one or more processors being configured to perform a method according to one or more of aspects 1 to 36.

[0149] Aspect 39: An apparatus for wireless communication, comprising at least one apparatus for performing a method according to one or more of aspects 1 to 36.

[0150] Aspect 40: A non-transitory computer-readable medium storing code for wireless communication, the code comprising instructions executable by a processor to perform a method according to one or more of aspects 1 to 36.

[0151] Aspect 41: A non-transitory computer-readable medium storing an instruction set for wireless communication, the instruction set comprising one or more instructions which, when executed by one or more processors of a device, cause the device to perform a method according to one or more of aspects 1 to 36.

[0152] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit the aspects to the precise forms disclosed. Modifications and variations are possible in light of the above disclosure or may be acquired from practice of these aspects.

[0153] As used herein, the term "component" is intended to be broadly interpreted as hardware, firmware, and / or a combination of hardware and software. As used herein, a processor is implemented in hardware, firmware, and / or a combination of hardware and software.

[0154] As used herein, satisfying a threshold may refer to a value greater than a threshold, greater than or equal to the threshold, less than a threshold, less than or equal to a threshold, equal to a threshold, not equal to a threshold, etc., depending on the context.

[0155] Obviously, the systems and / or methods described herein can be implemented in various forms of hardware, firmware, and / or a combination of hardware and software. The actual dedicated control hardware or software code used to implement these systems and / or methods does not limit these aspects. Therefore, the operation and behavior of the systems and / or methods are described herein without reference to specific software code, and it should be understood that software and hardware can be designed to implement the systems and / or methods based at least in part on the description herein.

[0156] Even if the specific combination of features is set forth in the claims or disclosed in the specification, these combinations are not intended to limit the disclosure of each aspect. In fact, many of these features can be combined in a manner not specifically set forth in the claims and / or disclosed in the specification. Although each dependent claim listed below may directly depend on only one claim, the disclosure of each aspect includes each dependent claim combined with all other claims in the claim set. The phrase "at least one" mentioned in the list of items refers to any combination of these items, including a single member. As an example, "at least one of the following: a, b or c" is intended to cover any combination of a, b, c, a to b, a to c, b to c and a to b to c and multiples of the same elements (e.g., a to a, a to a to a, a to a to b, a to a to c, a to b to b, a to c to c, b to b, b to b to c, c to c and c to c to c or any other order of a, b and c).

[0157] Unless explicitly described, any element, action or instruction used in this article should not be interpreted as critical or essential. In addition, as used herein, the articles "one" and "an" are intended to include one or more items, and can be used interchangeably with "one or more". In addition, as used herein, the terms "set" and "group" are intended to include one or more items (e.g., related items, non-related items, combinations of related items and non-related items, etc.), and can be used interchangeably with "one or more". If only one item is intended, the phrase "only one" or similar language is used. In addition, as used herein, the terms "has", "have", "having" etc. are intended to be open terms. In addition, unless otherwise explicitly stated, the phrase "based on" is intended to mean "based at least in part on".

Claims

1. A user equipment (UE) for wireless communication, comprising: Memory; as well as one or more processors operably coupled to the memory, the memory and the one or more processors being configured to: receiving or determining information indicating a timing advance for the non-serving cell for the UE based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; as well as Inter-cell mobility operations are performed based at least in part on the timing advance of the non-serving cell for the UE.

2. The UE according to claim 1, wherein: The inter-cell mobility operation is based on layer 1 or layer 2 inter-cell mobility operation.

3. The UE according to claim 1, wherein: The non-serving cell is a neighboring cell of the UE.

4. The UE according to claim 1, wherein: The non-serving cell is identified by a physical cell identifier of the non-serving cell.

5. The UE according to claim 1, wherein: The timing advance is associated with the timing advance group to which the non-serving cell belongs.

6. The UE according to claim 5, wherein: The one or more processors are further configured to: Signaling indicating that the non-serving cell belongs to the timing advance group is received.

7. The UE according to claim 1, wherein: The information indicating the timing advance indicates the timing advance group identifier of the timing advance group to which the non-serving cell belongs.

8. The UE according to claim 7, wherein: The timing advance group identifier is signaled using at least one of: radio resource control signaling, a medium access control control element, or downlink control information.

9. The UE according to claim 7, wherein: The timing advance is for all cells in the timing advance group.

10. The UE according to claim 1, wherein: The timing advance is based at least in part on a random access channel (RACH) preamble sent by the UE to the non-serving cell.

11. The UE according to claim 10, wherein: The RACH preamble is triggered by a physical downlink control channel command received from a serving cell of the UE or from the non-serving cell.

12. The UE according to claim 10, wherein: The information indicating the timing advance is received in a RACH response.

13. The UE according to claim 1, wherein: The timing advance is based at least in part on a sounding reference signal (SRS) sent by the UE to at least one of a serving cell or the non-serving cell.

14. The UE according to claim 13, wherein: The SRS is scheduled by the serving cell.

15. The UE according to claim 13, wherein: The SRS is triggered by downlink control information.

16. The UE according to claim 1, wherein: The one or more processors are further configured to: Respective signals are received from the non-serving cell and the serving cell, wherein determining the information indicative of the timing advance is based at least in part on measuring a received timing difference between the respective signals.

17. The UE according to claim 16, wherein: The one or more processors are further configured to: Information indicating the reception timing difference is transmitted to at least one of the serving cell or the non-serving cell.

18. The UE according to claim 16, wherein: The corresponding signal includes a synchronization signal block.

19. A network entity for wireless communication, comprising: Memory; as well as one or more processors operably coupled to the memory, the memory and the one or more processors being configured to: determining information indicative of a timing advance for a non-serving cell of a user equipment (UE) based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; as well as The information indicating the timing advance is sent.

20. The network entity according to claim 19, wherein: The one or more processors are further configured to: A layer 1 or layer 2 based inter-cell mobility operation is performed based at least in part on the timing advance of the non-serving cell for the UE.

21. The network entity according to claim 19, wherein: The non-serving cell is a neighboring cell of the UE.

22. The network entity according to claim 19, wherein: The non-serving cell is identified by a physical cell identifier of the non-serving cell.

23. The network entity according to claim 19, wherein: The timing advance is associated with the timing advance group to which the non-serving cell belongs.

24. The network entity according to claim 23, wherein: The one or more processors are further configured to: Sending signaling indicating that the non-serving cell belongs to the timing advance group.

25. The network entity according to claim 19, wherein: The information indicating the timing advance indicates the timing advance group identifier of the timing advance group to which the non-serving cell belongs.

26. The network entity according to claim 19, wherein: The timing advance is based at least in part on a random access channel (RACH) preamble sent by the UE to the non-serving cell.

27. The network entity according to claim 19, wherein: The timing advance is based at least in part on receiving a sounding reference signal (SRS) from the UE.

28. The network entity according to claim 27, wherein: The one or more processors are further configured to: The SRS is scheduled to be sent to the serving cell or the non-serving cell.

29. A wireless communication method performed by a user equipment (UE), comprising: receiving or determining information indicating a timing advance for the non-serving cell for the UE based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; as well as Inter-cell mobility operations are performed based at least in part on the timing advance of the non-serving cell for the UE.

30. A wireless communication method performed by a network entity, comprising: determining information indicative of a timing advance for a non-serving cell of a user equipment (UE) based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; as well as The information indicating the timing advance is sent.

31. A non-transitory computer-readable medium storing one or more instructions for wireless communication, which, when executed by one or more processors of a UE, may cause the one or more processors to: receiving or determining information indicating a timing advance for the non-serving cell for the UE based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; and Inter-cell mobility operations are performed based at least in part on the timing advance of the non-serving cell for the UE.

32. A non-transitory computer-readable medium storing one or more instructions for wireless communication, which, when executed by one or more processors of a network entity, may cause the one or more processors to: determining information indicative of a timing advance for a non-serving cell of a user equipment (UE) based at least in part on a timing advance group identifier for a timing advance group to which the non-serving cell belongs; and The information indicating the timing advance is sent.

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