Uplink timing associated with uplink transmission configuration indication (TCI) status

Abstract

A method of wireless communication by a UE (User Equipment) includes setting a timing parameter based on an uplink TCI (Transmission Configuration Indication) state. The method further includes adjusting an uplink transmit timing for the uplink transmission based on the timing parameter.

Description

[0001] This application is a divisional application of the application with the filing date of March 2, 2021, application number 202180023087.2, and title "Uplink Timing Associated with Uplink Transmission Configuration Indication (TCI) State".

[0002] Cross-reference to related applications

[0003] This application claims the priority of U.S. Patent Application No. 17 / 189,049, filed on March 1, 2021, and titled "UPLINK TIMING ASSOCIATED WITH UPLINK TRANSMISSION CONFIGURATION INDICATION (TCI) STATE", which claims the benefit of U.S. Provisional Patent Application No. 63 / 002,238, filed on March 30, 2020, and titled "UPLINK TIMING ASSOCIATED WITH UPLINK TRANSMISSION CONFIGURATION INDICATION (TCI) STATE". The entire disclosure of the above applications is hereby expressly incorporated by reference. Technical field

[0004] Broadly speaking, aspects of the present disclosure relate to wireless communication, and more specifically, aspects of the present disclosure relate to associating uplink timing with an uplink transmission configuration indication (TCI) state. Background art

[0005] Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, and broadcasting. A typical wireless communication system may employ a multiple access technology 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 / Advanced LTE is an enhanced set of the universal mobile telecommunications system (UMTS) mobile standard released by the 3rd Generation Partnership Project (3GPP).

[0006] A wireless communication network can include multiple base stations (BSs) capable of supporting communication for multiple user equipments (UEs). The user equipment (UE) can communicate with the base station (BS) via the downlink and the uplink. The downlink (or forward link) refers to the communication link from the BS to the UE, and the uplink (or reverse link) refers to the communication link from the UE to the BS. As will be described in more detail, the BS can be referred to as a Node B, gNB, access point (AP), radio head, transmit receive point (TRP), New Radio (NR) BS, 5G Node B, etc.

[0007] The above multi-access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different user equipments to communicate at the urban, national, regional, and even global levels. New Radio (NR) (which may also be referred to as 5G) is an enhanced set of the LTE mobile standard released by the 3rd Generation Partnership Project (3GPP). NR is designed to better integrate with other open standards by improving spectral efficiency, reducing costs, enhancing services, utilizing new spectrums, and using Orthogonal Frequency Division Multiplexing with Cyclic Prefix (CP-OFDM) on the downlink (DL) and CP-OFDM and / or SC-FDM (e.g., also referred to as Discrete Fourier Transform Spread OFDM (DFT-s-OFDM)) on the uplink (UL), so as to better support mobile broadband Internet access and support beamforming, Multiple-Input Multiple-Output (MIMO) antenna technology, and carrier aggregation.

[0008] Uplink communication currently supports only one transmission timing for each Timing Advance Group (TAG). However, when the UE transmission configuration changes, this may cause timing jitter on the receiver side (e.g., the base station). For example, when the uplink transmission beam switches, the receiver timing may shift due to differences in propagation delays. Timing jitter in the receiver may cause inter-symbol interference and / or inter-carrier interference and degrade the overall system performance. It would be desirable to provide more flexible uplink timing determination for 5G NR communication. SUMMARY OF THE INVENTION

[0009] In one aspect of the present disclosure, a method for a user equipment (UE) to perform wireless communication includes: setting timing parameters based on an uplink TCI (Transmission Configuration Indication) state. The method further includes: adjusting an uplink transmission timing for uplink transmission based on the timing parameters.

[0010] In another aspect of the present disclosure, a UE (User Equipment) for wireless communication includes: a memory, and at least one processor operatively coupled to the memory. The memory and the processor are configured to: set timing parameters based on an uplink TCI (Transmission Configuration Indication) state. The memory and the processor are further configured to: adjust an uplink transmission timing for uplink transmission based on the timing parameters.

[0011] In another aspect of the present disclosure, a base station for wireless communication includes: a memory, and at least one processor operatively coupled to the memory. The memory and the processor are configured to: set timing parameters for a User Equipment (UE) based on an uplink TCI (Transmission Configuration Indication) state. The memory and the processor are further configured to: adjust an uplink transmission timing for uplink transmission based on the timing parameters.

[0012] In another aspect of the present disclosure, a UE (User Equipment) includes: a unit for setting timing parameters based on an uplink TCI (Transmission Configuration Indication) state. The UE further includes: a unit for adjusting an uplink transmission timing for uplink transmission based on the timing parameters.

[0013] Broadly speaking, aspects include methods, apparatuses, systems, computer program products, non-transitory computer-readable media, user equipment, base stations, wireless communication devices, and processing systems substantially as described with reference to the accompanying drawings and the specification and as illustrated by the accompanying drawings and the specification.

[0014] The features and technical advantages of examples in accordance with the present disclosure have been outlined rather broadly above so that the detailed description that follows may be better understood. Additional features and advantages will be described. The disclosed concepts and specific examples may be readily utilized as a basis for modifying or designing other structures for carrying out the same purposes of the present disclosure. Such equivalent constructions do not depart from the scope of the appended claims. When considered in conjunction with the accompanying drawings, the characteristics of the disclosed concepts (both their organization and method of operation) as well as the associated advantages will be better understood from the following description. Each of the drawings in the accompanying drawings is provided for purposes of illustration and description and is not to be construed as defining a limitation of the claims. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Specific descriptions can be obtained by referring to various aspects, some of which are illustrated in the accompanying drawings, so that the features of the present disclosure can be understood in detail. However, it should be noted that the accompanying drawings only illustrate certain aspects of the present disclosure and are therefore not considered to limit the scope of the present disclosure, because the description may recognize other equally effective aspects. The same reference numerals in different drawings may identify the same or similar elements.

[0016] Figure 1 is a block diagram conceptually illustrating an example of a wireless communication network according to various aspects of the present disclosure.

[0017] Figure 2 is a block diagram conceptually illustrating an example of a base station communicating with a user equipment (UE) in a wireless communication network according to various aspects of the present disclosure.

[0018] Figure 3 is a diagram of beam pairing according to certain aspects of the present disclosure.

[0019] Figure 4 is a diagram of setting uplink timing based on the strongest path according to aspects of the present disclosure.

[0020] Figure 5A and 5B illustrate timing based on service type according to aspects of the present disclosure.

[0021] Figure 6 is a diagram illustrating an example process, such as performed by a user equipment (UE), according to various aspects of the present disclosure. Detailed Description

[0022] Various aspects of the present disclosure are more fully described with reference to the accompanying drawings. However, the present disclosure may be embodied in many different forms and should not be construed as limited to any specific structure or function presented throughout the present disclosure. Rather, these aspects are provided so that the present disclosure will be comprehensive and complete, and will fully convey the scope of the present disclosure to those skilled in the art. Based on the teachings, those skilled in the art should recognize that the scope of the present disclosure is intended to cover any aspect of the disclosure, whether implemented independently of any other aspect of the present disclosure or in combination with any other aspect. For example, using any number of the aspects described, an apparatus may be implemented or a method may be practiced. In addition, the scope of the present disclosure is intended to cover such an apparatus or method practiced using other structures, functions, or a combination of structures and functions in addition to or different from the various aspects of the present disclosure described. It should be understood that any aspect of the present disclosure disclosed may be embodied by one or more elements of the claims.

[0023] Aspects of a telecommunications system will now be presented with reference to various apparatuses and techniques. These apparatuses and techniques will be described in the following detailed description through various blocks, modules, components, circuits, steps, processes, algorithms, etc. (collectively referred to as "elements"), and will be illustrated in the accompanying drawings. These elements can be implemented using hardware, software, or a combination thereof. Whether such an element is implemented as hardware or software depends on the particular application and the design constraints imposed on the overall system.

[0024] It should be noted that although terms commonly associated with 5G and later wireless technologies may be used herein to describe aspects, aspects of the present disclosure can be applied to communication systems based on other generations (such as and including 3G and / or 4G technologies).

[0025] 5G NR supports the configuration of transmission configuration indication (TCI) states for quasi-co-location (QCL) indication for the physical downlink control channel (PDCCH) and physical downlink shared channel (PDSCH). Each TCI state consists of a set of one downlink reference signal (RS) for different QCL types. The downlink reference signal can be a synchronization signal block (SSB), a tracking reference signal (TRS), and an aperiodic / periodic / semi-persistent channel state information reference signal (CSI-RS). The QCL type indicates the temporal, frequency, and spatial relationship with the source reference signal. Exemplary QCL types are defined in Section 5.1.5 of 3GPP TR38.214 and include type A (Doppler shift, Doppler spread, average delay, delay spread), type B (Doppler shift, Doppler spread), type C (Doppler shift and average delay), and type D (spatial Rx (receive) parameters).

[0026] For DL channel tracking, tracking reference signal (TRS) resources can be configured. Separate tracking loops (e.g., time, frequency, Doppler, and delay) can be maintained for each TRS. When configured in a TCI state, each TRS can be used as a source reference signal (RS) for downlink (DL) timing (e.g., type A / C).

[0027] 5G NR supports multiple DL timing references, one for each configured TRS. Each DL channel uses the appropriate timing reference as indicated by the TCI state. Multiple timing references are useful, for example, in multi-beam based communication scenarios (such as NR FR2 (frequency 2 - millimeter wave)). Each beam pairing link may experience different physical propagation paths and have different delays. Therefore, separate TRSs can be configured for each beam pairing link for time tracking.

[0028] Unlike DL, UL currently supports only one Tx (transmission) timing for each timing advance group (TAG). However, when the UE Tx configuration changes, this may cause timing jitter at the receiver side (e.g., the base station). For example, when the UL Tx beam is switched, the receiver timing may shift due to differences in propagation delays. Timing jitter in the receiver may cause inter-symbol interference and / or inter-carrier interference and degrade the overall system performance. Advanced UE capabilities that support multi-beam / multi-panel simultaneous transmission may result in additional timing inaccuracies using a single timing advance (TA) command (or transmission timing).

[0029] In accordance with the present disclosure, when the UL TCI framework is supported, UL timing determination for 5G NR is provided. More specifically, the UE adjusts its transmission timing according to the QCL type source RS indicated by the UL TCI state. That is, the UE adjusts its transmission timing according to the TCI. Depending on the source reference signal, the UE may calculate the timing in different ways. The present disclosure contemplates any QCL type that indicates time and frequency parameters, such as, for example, QCL types A, B, and C.

[0030] Figure 1 FIG. is a diagram of a network 100 in which aspects of the present disclosure may be practiced. The network 100 may be a 5G or NR network or some other wireless network (e.g., an LTE network). The wireless network 100 may include multiple base stations (BSs) 110 (shown as BS110a, BS110b, BS110c, and BS110d) and other network entities. A BS is an entity that communicates with 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 the coverage area of a BS and / or the BS subsystem serving that coverage area, depending on the context in which the term is used.

[0031] The BS can provide communication coverage for macro cells, pico cells, femto cells, and / or another type of cell. A macro cell can cover a relatively large geographical area (e.g., with a radius of several kilometers) and can allow unrestricted access by UEs with service subscriptions. A pico cell can cover a relatively small geographical area and can allow unrestricted access by UEs with service subscriptions. A femto cell can cover a relatively small geographical area (e.g., a residence) and can allow restricted access by UEs associated with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG)). The BS for a macro cell can be referred to as a macro BS. The BS for a pico cell can be referred to as a pico BS. The BS for a femto cell can be referred to as a femto BS or a home BS. In Figure 1 the example shown in, BS110a can be a macro BS for macro cell 102a, BS110b can be a pico BS for pico cell 102b, and BS110c 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" can be used interchangeably.

[0032] In some aspects, the cell may not have to be stationary, and the geographical area of the cell can move according to the location of the mobile BS. In some aspects, the BSs can 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 (e.g., direct physical connections using any suitable transport network, virtual networks, etc.).

[0033] The wireless network 100 can also include relay stations. A relay station is an entity that can receive data transmissions from an upstream station (e.g., a BS or a UE) and send the data transmissions to a downstream station (e.g., a UE or a BS). A relay station can also be a UE capable of relaying transmissions for other UEs. In Figure 1 the example shown in, relay station 110d can communicate with macro BS110a and UE 120d to facilitate communication between BS110a and UE 120d. A relay station can also be referred to as a relay BS, a relay base station, a repeater, etc.

[0034] The wireless network 100 can be a heterogeneous network including different types of BSs (e.g., macro BS, pico BS, femto BS, relay BS, etc.). These different types of BSs can have different transmit power levels, different coverage areas, and different impacts on interference in the wireless network 100. For example, a macro BS can have a high transmit power level (e.g., 5 to 40 watts), while pico BSs, femto BSs, and relay BSs can have lower transmit power levels (e.g., 0.1 to 2 watts).

[0035] The network controller 130 can be coupled to a group of BSs and can provide coordination and control for these BSs. The network controller 130 can communicate with the BSs via a backhaul. The BSs can also communicate with each other directly or indirectly, e.g., via a wireless or wired backhaul.

[0036] UEs 120 (e.g., 120a, 120b, 120c) can be dispersed throughout the wireless network 100, and each UE can be stationary or mobile. A UE can also be referred to as an access terminal, terminal, mobile station, user unit, station, etc. A 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 device, a camera, a gaming device, a netbook, a smartbook, a superbook, a medical device or apparatus, a biometric sensor / device, a wearable device (smart watch, smart clothing, smart glasses, smart wristband, smart jewelry (e.g., smart ring, smart bracelet, etc.)), an entertainment device (e.g., a music or video device, or a satellite wireless unit, etc.), 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.

[0037] Some UEs can be considered 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., which can communicate with a base station, another device (e.g., a remote device), or some other entity. A wireless node can provide a connection to or from 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 can be considered Internet of Things (IoT) devices, and / or can be implemented as narrowband IoT (NB-IoT) devices. Some UEs can be considered customer premise equipment (CPE). The UE 120 can be included inside a housing that houses components of the UE 120, such as a processor component, a memory component, etc.

[0038] Generally, any number of wireless networks can be deployed in a given geographical area. Each wireless network can support a specific RAT and can operate on one or more frequencies. The RAT can also be referred to as radio technology, air interface, etc. The frequency can also be referred to as carrier, frequency channel, etc. Each frequency can support a single RAT in a given geographical area to avoid interference between wireless networks of different RATs. In some cases, an NR or 5G RAT network can be deployed.

[0039] In some aspects, two or more UEs 120 (e.g., shown as UEs 120a and 120e) can communicate directly using one or more sidelink channels (e.g., without using the base station 110 as an intermediary for communicating with each other). For example, the UEs 120 can communicate using peer-to-peer (P2P) communication, device-to-device (D2D) communication, vehicle-to-everything (V2X) protocols (e.g., which can include vehicle-to-vehicle (V2V) protocols, vehicle-to-infrastructure (V2I) protocols, etc.), mesh networks, etc. In such cases, the UEs 120 can perform scheduling operations, resource selection operations, and / or other operations described elsewhere as being performed by the base station 110.

[0040] As noted above, Figure 1 is provided only by way of example. Other examples may be different from the example regarding Figure 1 described.

[0041] Figure 2 shows a block diagram of a design 200 of a base station 110 and a UE 120 (which can be one of the base stations in Figure 1 and one of the UEs in the UE). The base station 110 can be equipped with T antennas 234a to 234t, and the UE 120 can be equipped with R antennas 252a to 252r, where generally, T≥1 and R≥1.

[0042] At base station 110, transmit processor 220 may receive data for one or more UEs from data source 212, select one or more modulation and coding schemes (MCSs) for the UE based at least in part on channel quality indicators (CQIs) received from each UE, process (e.g., encode and modulate) the data for the UE based at least in part on the MCSs selected for each UE, and provide data symbols for all UEs. 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. Transmit processor 220 may also generate reference symbols for reference signals (e.g., cell-specific reference signal (CRS)) and synchronization signals (e.g., primary synchronization signal (PSS) and secondary synchronization signal (SSS)). Transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, control symbols, overhead symbols, and / or reference symbols (if applicable), and may provide T output symbol streams to T modulators (MODs) 232a through 232t. Each modulator 232 may process the respective 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 through 232t may be transmitted via T antennas 234a through 234t, respectively. According to various aspects described in more detail below, synchronization signals may be generated using position coding to convey additional information.

[0043] At the UE 120, antennas 252a through 252r may receive downlink signals from the base station 110 and / or other base stations and may provide the received signals to demodulators (DEMOD) 254a through 254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, down-convert, 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. The MIMO detector 256 may obtain the received symbols from all R demodulators 254a through 254r, perform MIMO detection on the received symbols (if applicable), and provide the detected symbols. The receive processor 258 may process (e.g., demodulate and decode) the detected symbols, provide the decoded data for the UE 120 to the data sink 260, and provide the decoded control information and system information to the controller / processor 280. The channel processor may determine a reference signal received power (RSRP), a received signal strength indicator (RSSI), a reference signal received quality (RSRQ), a channel quality indicator (CQI), etc. In some aspects, one or more components of the UE 120 may be included in a housing.

[0044] On the uplink, at the UE 120, the transmit processor 264 may receive and process data from the data source 262 and control information from the controller / processor 280 (e.g., for reporting including RSRP, RSSI, RSRQ, CQI, etc.). The transmit processor 264 may also generate reference symbols for one or more reference signals. The symbols from the transmit processor 264 may be precoded by the 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, the uplink signals from the UE 120 and other UEs may be received by the antenna 234, processed by the demodulator 254, detected by the MIMO detector 236 (if applicable), and further processed by the receive processor 238 to obtain the decoded data and control information transmitted by the UE 120. The receive processor 238 may provide the decoded data to the data sink 239 and provide the decoded control information to the 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.

[0045] The controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or Figure 2Any other component in may perform one or more techniques associated with machine learning for non-linearity, as described in more detail elsewhere. For example, the controller / processor 240 of the base station 110, the controller / processor 280 of the UE 120, and / or Figure 2 Any other component in may perform or direct operations of processes such as, for example, Figure 6 and / or other processes as described. The memories 242 and 282 may store data and program codes for the base station 110 and the UE 120, respectively. The scheduler 246 may schedule the UE for data transmission on the downlink and / or uplink.

[0046] In some aspects, the UE 120 may include: a unit for setting, a unit for adjusting, a unit for indicating, a unit for receiving, a unit for deriving, a unit for calculating, and a unit for continuing to apply. Such units may include one or more components of the UE 120 described in conjunction with Figure 2 description.

[0047] As noted above, Figure 2 is provided only by way of example. Other examples may differ from the examples described with respect to Figure 2 description.

[0048] In some cases, different types of devices that support different types of applications and / or services may coexist in a cell. Examples of different types of devices include UE handheld devices, customer premise equipment (CPE), vehicles, Internet of Things (IoT) devices, etc. Examples of different types of applications include ultra-reliable low-latency communication (URLLC) applications, massive machine type communication (mMTC) applications, enhanced mobile broadband (eMBB) applications, vehicle-to-everything (V2X) applications, etc. Additionally, in some cases, a single device may support different applications or services simultaneously.

[0049] As described above, 5G NR supports the configuration of transmission configuration indication (TCI) states for quasi - co - location (QCL) indication for the physical downlink control channel (PDCCH) and physical downlink shared channel (PDSCH). Each TCI state consists of a set of one downlink reference signal (RS) for different QCL types. The downlink reference signal can be a synchronization signal block (SSB), a tracking reference signal (TRS), and an aperiodic / periodic / semi - persistent channel state information reference signal (CSI - RS). The QCL type indicates the temporal, frequency, and spatial relationships with the source reference signal. Exemplary QCL types are defined in Section 5.1.5 of 3GPP TR38.214 and include type A (Doppler frequency shift, Doppler spread, average delay, delay spread), type B (Doppler frequency shift, Doppler spread), type C (Doppler frequency shift and average delay), and type D (spatial Rx range).

[0050] For DL channel tracking, tracking reference signal (TRS) resources can be configured. Separate tracking loops (e.g., time, frequency, Doppler, and delay) can be maintained for each TRS. When configured in a TCI state, each TRS can serve as the source reference signal (RS) for downlink (DL) timing (e.g., type A / C).

[0051] 5G NR supports multiple DL timing references, one for each configured TRS. Each DL channel uses the appropriate timing reference as indicated by the TCI state. Multiple timing references are useful, for example, in multi - beam - based communication scenarios such as NR FR2 (frequency 2 - millimeter wave). Each beam - paired link may experience different physical propagation paths and have different delays. Therefore, separate TRSs can be configured for each beam - paired link for time tracking.

[0052] Figure 3 is a diagram of beam pairing according to certain aspects of the present disclosure. Refer to Figure 3, the first transmission beam (Tx beam 1) from the base station (BS) 110 is paired with the first reception beam (Rx beam 1) at the user equipment (UE) 120. The first transmission beam (Tx beam 1) is associated with the first CSI-RS (CSI-RS1) for beam management and the first tracking reference signal (TRS1) for latency. In this example, the TCI state 1 is defined as: (CSI-RS1 for QCL-type D, TRS1 for QCL-type A). The second transmission beam (Tx beam 2) from the base station 110 is paired with the second reception beam (Rx beam 2) at the UE 120. The second transmission beam (Tx beam 2) is associated with the second CSI-RS (CSI-RS2) for beam management and the second tracking reference signal (TRS2) for latency. In this example, the TCI state 2 is defined as: (CSI-RS2 for QCL-type D, TRS2 for QCL-type A). If the PDCCH and PDSCH are configured with the TCI state 1, the UE uses the first reception beam (Rx beam 1) and the reception timing estimation from the TRS1 to receive the PDCCH and PDSCH.

[0053] For uplink (UL) beam management, the spatial relationship (UL spatial Tx parameter) to be used for UL transmission is configured via radio resource control (RRC) and indicated in the downlink (DL) control information, which is similar to QCL-type D in the DL (assuming beam correspondence).

[0054] The UL timing determination in 5G NR is similar to that in LTE. NR uses the timing advance (TA) command from the base station for UL transmission timing adjustment, where multiple timing advance groups (TAGs) are supported in carrier aggregation and in the dual-connection scenario. For the physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), and sounding reference signal (SRS) within the same TAG, the same timing is assumed.

[0055] It is expected that the uplink TCI framework is similar to the downlink TCI framework. For the uplink, other QCL types can be supported and different source RSs can also be supported. It is also expected that the signaling aspect is more symmetric between the uplink and the downlink.

[0056] To have a unified DL / UL TCI framework, the UL TCI includes a source RS to indicate the UL Tx beam for the target UL RS / channel. The source RS can be SRS, SSB, and CSI-RS. The target UL RS / channel can be PUCCH, SRS, physical random access channel (PRACH), and PUSCH. Other QCL types similar to DL are also possible. Table 1 shows the possible TCI states for uplink communication.

[0057]

[0058]

[0059] Table 1

[0060] Unlike DL, UL currently supports only one Tx timing for each timing advance group (TAG). However, when the UE Tx configuration changes, this may cause timing jitter at the receiver side (e.g., the base station). For example, when the UL Tx beam switches, the receiver timing may shift due to differences in propagation delays. Timing jitter in the receiver may cause inter-symbol interference and / or inter-carrier interference and degrade the overall system performance. Advanced UE features that support multi-beam / multi-panel simultaneous transmission may cause additional timing inaccuracies using a single timing advance (TA) command (or transmit timing).

[0061] According to the present disclosure, when the UL TCI framework is supported, UL timing determination for 5G NR is provided. More specifically, the UE adjusts its transmit timing according to the QCL type source RS indicated by the UL TCI state. That is, the UE adjusts its transmit timing according to the TCI. According to the source reference signal, the UE can calculate the timing in different ways. The present disclosure contemplates any QCL type that indicates time and frequency parameters, e.g., such as QCL types A, B, and C.

[0062] Now consider two cases. If the QCL type source reference signal in the UL TCI is the SRS in a configured SRS resource set, the UE follows the same transmit timing as the SRS resource set.

[0063] In the second case, the QCL type source reference signal in the UL TCI is a DL RS, such as an SSB. In the second case, if the DL RS is a TRS (e.g., configurations 2, 3, and 4 in Table 1), the UE can calculate a beam-specific delay adjustment according to the DL RS. The tracking reference signal (TRS) enables the UE to define timing parameters. The beam-specific delay adjustment can be applied to the common TA (timing advance) value to determine the beam-specific transmit timing.

[0064] Different transmit timings can be calculated and applied for different uplink channels / SRSs (e.g., UL TCI states). Each uplink beam can have its own uplink TCI state. However, the TCI state does not need to be different for each beam. Multiple beams can have the same uplink timing parameters. The transmit timing t of the channel / SRS (UL TCI state) i i is calculated as follows:

[0065] t i = T Ref + Δ i ,

[0066] where T Ref is a common reference timing calculated / adjusted by the timing advance (TA) command for the timing advance group (TAG), and Δ i is the adjustment for each channel / SRS (UL TCI state). The initial value of Δ i can be zero (e.g., the same timing for all channels / SRSs (UL TCI states) in the TAG).

[0067] Each UL channel or SRS has a spatial QCL assumption, as shown in Table 2.

[0068]

[0069] Table 2

[0070] According to aspects of the present disclosure, within a timing advance group (TAG), sub-TAG definitions are supported. Such sub-TAG definitions can be RRC-configured or more dynamically updated / activated using a media access control - control element (MAC-CE). The UE can indicate support for sub-TAGs via capability signaling including the maximum number of sub-TAGs. The exchange of capability information between the base station and the UE occurs before the timing adjustment process. Each UL TCI state can be labeled with a sub-TAG index, and each sub-TAG can contain one or more UL TCI states.

[0071] A new TA command can be defined (e.g., carried in a MAC-CE or downlink control information (DCI)). In a first option, the new timing advance (TA) command can include one or more sub-TAG indices to which the command is applied. Alternatively, a single MAC-CE can use multiple octets within the same MAC-CE to update multiple sub-TAG TA values. Traditional TA commands can still be generally applied to all sub-TAGs.

[0072] According to a further aspect of the present disclosure, new higher layer parameters can be defined. The new parameter can be referred to as "timingReferenceRS". The new higher layer parameter can indicate the SSB, CSI-RS (desirably, TRS), or SRS to which the TA command is applied. The UE measures the timingReferenceRS and estimates the delay, spread, etc. Then, the estimation is applied to the UE timing.

[0073] For example, TRS1 and TRS2 can be configured for QCL-Type C in UL TCI1 and TCI2, respectively. Assume that TRS1 is configured as the timingReferenceRS. Assume that based on the UE time tracking loop, there is a Δ T Rx timing difference between TRS1 and TRS2. Thus, when the UE transmits a UL beam with TCI2, on top of the current TA value T, the UE applies a compensation (e.g., T + Δ T ). Assume beam reciprocity. The details of the TA compensation with respect to the timingReferenceRS are specified based on the UE implementation.

[0074] If the UL Tx beam is quasi-co-located with a DL RS (SSB or non-zero power (NZP)-CSI-RS), the timing adjustment can be calculated based on the Rx timing of the DL RS. If the UE is configured with a tracking reference signal (TRS) that is spatially quasi-co-located with the same DL RS, the Rx timing adjustment can be derived based on the time tracking loop or channel power delay profile (PDP) estimation associated with the TRS.

[0075] Figure 4 is a diagram of setting the uplink timing based on the strongest path according to aspects of the present disclosure. Now, an example for the codebook-based PUSCH will be provided. Together with the scheduling DCI, the UL beam is indicated by the QCL reference to the DL NZP-CSI-RS or SSB. The UE is configured with a TRS that is quasi-co-located with the same NZP-CSI-RS or SSB. The UE estimates the power delay profile (PDP) of the DL multipath channel according to the TRS, as Figure 4 shown. The Rx reference time (time 0) is determined based on the Rx fast Fourier transform (FFT) timing. According to the estimated PDP, the strongest path delay or root mean square (RMS) delay spread can be used for the UL timing adjustment Δ i = -α × t DL , where ɑ is a scaling factor. For example, the estimated PDP can be scaled and used to adjust the timing parameters for the beam.

[0076] If the UL Tx beam is quasi - co - located with the DL RS, but there is no TRS that is quasi - co - located with the DL RS, or the UL Tx beam is not quasi - co - located with the DL RS, then the UL is spatially quasi - co - located with the SRS resource. In some cases, the SRS (except when SRS - SetUse = 'nonCodebook') is not configured with a spatial relationship, e.g., SRS - SpatialRelationInfo. For example, the UE may have performed autonomous beam selection (e.g., without a previous SRS transmission). In this case, according to another aspect of the present disclosure, the timing adjustment can be calculated based on the Rx timing of one or more DL RSs. If the UE is configured with N≥1 TRS resources, the UL timing adjustment can be determined as Δ i =-α×t DL . The parameter t DL can be the average or median of the strongest path delays (or RMS delay spreads) of N PDPs estimated through N TRSs. The parameter t DL can be the minimum of the strongest path delays (or RMS delay spreads) of N PDPs estimated through N TRSs. In another configuration, the parameter t DL can be the strongest path delay (or RMS delay spread) of the composite PDP of N PDPs, or a default value signaled by the base station or specified in the 3GPP standard (possibly, Δ i =0).

[0077] In some cases, the UE may not be able to apply different UL Tx timings to different UL channels and SRSs (e.g., due to UE capability limitations). In this case, the UE can apply a single timing adjustment value Δ to all UL channels and SRSs. The parameter Δ can be derived based on the SSB or the configured DL RS (e.g., TRS resource). Similar calculations as discussed above can be used. The UE can be configured by the base station to use a specific DL RS (or set of RSs) for timing calculation. Alternatively, a default DL RS can be specified in the 3GPP standard. In one example, the default DL RS is the TRS resource with the lowest ID.

[0078] According to yet another aspect of the present disclosure, when UCI is transmitted on the PUSCH (instead of the PUCCH), the PUSCH timing can be applied. That is, the PUSCH beam (e.g., TCI state) can be different from the PUCCH beam (e.g., TCI state). In this case, the TCI state (e.g., timing information) for the PUSCH is used for the control information transmitted on the PUSCH.

[0079] According to another aspect of the present disclosure, when there is a Bandwidth Part (BWP) switch, the timing may change. Thus, the UE may use the timing from the original BWP within a grace period. The grace period means a certain period of time until the UE calculates a new reliable timing adjustment in the new BWP. The grace period may be part of the UE capabilities or a configured parameter for BWP switching.

[0080] A further aspect of the present disclosure addresses the situation where a grant-free Ultra-Reliable Low-Latency Communication (URLLC) transmission from the UE punctures its own ongoing Enhanced Mobile Broadband (eMBB) PUSCH transmission. In some cases, the UL Tx timing may be different between the original UL transmission and the grant-free transmission. In such cases, to prevent puncturing, the grant-free transmission may follow the timing of the original PUSCH timing.

[0081] Figure 5A and 5B illustrates the service type-based timing according to aspects of the present disclosure. As Figure 5A shown, the URLLC Tx timing has a timing offset or timing difference relative to the timing of the eMBB transmission. The URLLC transmits at time t1, while the symbol 2 of the eMBB transmission is transmitted at time t2. In this example, the timing offset (e.g., the timing difference) is less than a threshold. According to aspects of the present disclosure, the URLLC Tx timing is shifted (shifted by up to the timing offset or timing difference) to follow the same Tx timing as the original eMBB Tx timing because the timing offset is less than the threshold. Thus, in this aspect, the URLLC symbol is transmitted at time t2 instead of at time t1.

[0082] Alternatively, if the time offset between two uplink transmissions is greater than the threshold, some samples of the original PUSCH may be discarded, as Figure 5B shown. In the first example (a), the symbol 2 of the Enhanced Mobile Broadband (eMBB) service is punctured by the Ultra-Reliable Low-Latency Communication (URLLC) service. In the first example (a), the URLLC Tx timing is shifted by up to the timing offset to follow the same Tx timing as the original eMBB Tx timing. In the second example (b), in addition to symbol 2, some samples of the eMBB symbol 1 are discarded to accommodate the URLLC Tx timing. That is, in the second example (b), the URLLC timing is not shifted.

[0083] As noted above, Figure 3 - 5B is provided as an example. Other examples may be different from the examples described with respect to Figure 3 - 5B

[0084] ​Figure 6 FIG. is a diagram illustrating an example process 600, such as performed by a UE, in accordance with various aspects of the present disclosure. Example process 600 is an example of setting uplink timing associated with an uplink transmission configuration indication (TCI) state.

[0085] As Figure 6 shown, in some aspects, process 600 may include: setting timing parameters based on an uplink TCI (transmission configuration indication) state (block 602). For example, a UE (e.g., using antenna 252, DEMOD 254, MIMO detector 256, receive processor 258, controller / processor 280, memory 282, etc.) may set the timing parameters, or a base station (e.g., using antenna 234, MOD 232, TXMIMO processor 230, transmit processor 220, controller / processor 240, memory 242, etc.) may set the timing parameters.

[0086] As Figure 6 shown, in some aspects, process 600 may include: adjusting an uplink transmit timing for an uplink transmission based on the timing parameters (block 604). For example, a UE (e.g., using antenna 252, MOD 254, TX MIMO processor 266, controller / processor 280, memory 282, etc.) may adjust the uplink transmit timing, or a base station (e.g., using antenna 234, MOD 232, TX MIMO processor 230, transmit processor 220, controller / processor 240, memory 242, etc.) may adjust the uplink transmit timing.

[0087] Implementation examples are described in the numbered clauses below:

[0088] 1. A method for wireless communication by a UE (user equipment), comprising:

[0089] setting timing parameters based on an uplink TCI (transmission configuration indication) state; and

[0090] adjusting an uplink transmit timing for an uplink transmission based on the timing parameters.

[0091] 2. The method according to clause 1, further comprising: setting the timing parameters based on a quasi - co - located (QCL) source reference signal (RS) specified by the uplink TCI state.

[0092] 3. The method according to clause 1 or 2, wherein the QCL source reference signal includes an SRS in a configured set of SRS (sounding reference signal) resources, and wherein setting the timing parameters includes setting the timing parameters to match the timing advance of the SRS resource set.

[0093] 4. The method according to any one of the preceding clauses, wherein setting the timing parameter includes setting the timing parameter by calculating a beam-specific timing advance, wherein the QCL source reference signal includes a downlink reference signal, and the downlink reference signal includes a TRS (Tracking Reference Signal), an SSB (Synchronization Signal Block), or a CSI-RS (Channel State Information Reference Signal).

[0094] 5. The method according to any one of the preceding clauses, further comprising: adjusting the uplink transmission timing for a plurality of uplink beams, each uplink beam having its own uplink TCI state.

[0095] 6. The method according to any one of the preceding clauses, further comprising: indicating the maximum number of sub-timing advance groups (TAGs) supported by the UE.

[0096] 7. The method according to any one of the preceding clauses, further comprising: receiving an indication of the number of sub-timing advance groups (TAGs) to be supported.

[0097] 8. The method according to any one of the preceding clauses, wherein the timing advance command includes at least one sub-timing advance group (TAG) index, and each sub-TAG includes at least one uplink TCI state.

[0098] 9. The method according to any one of the preceding clauses, wherein the Medium Access Control - Control Element (MAC-CE) includes a plurality of sub-timing advance group (TAG) updates.

[0099] 10. The method according to any one of the preceding clauses, further comprising:

[0100] receiving an indication of a timing reference RS (Reference Signal);

[0101] deriving a timing estimate for the timing reference RS; and

[0102] adjusting the timing parameter based on the timing estimate.

[0103] 11. The method according to any one of the preceding clauses, further comprising: adjusting the timing based on a time tracking loop or channel power delay profile estimate of a TRS (Tracking Reference Signal) that is spatially quasi-co-located with a source downlink RS, where the source downlink RS is quasi-co-located with the uplink transmission.

[0104] 12. The method according to any one of the preceding clauses further includes: when the source reference signal is not a tracking reference signal, or the source reference signal is an SRS (sounding reference signal) that is spatially quasi-co-located with the uplink transmission and the SRS is not configured with spatial relationship information, calculating the timing adjustment based on the timing estimation of at least one downlink reference signal.

[0105] 13. The method according to any one of the preceding clauses, wherein the calculation is based on the minimum value of the timing estimations from multiple downlink reference signals or the average value of the timing estimations of the multiple downlink reference signals.

[0106] 14. The method according to any one of the preceding clauses further includes: adjusting the uplink timing for a physical uplink shared channel (PUSCH) based on a parameter different from the parameter used to adjust the timing for a physical uplink control channel (PUCCH), wherein the TCI state for the PUCCH is different from the TCI state for the PUSCH.

[0107] 15. The method according to any one of the preceding clauses further includes: continuing to apply the adjusted uplink transmission timing during a period after switching the bandwidth part (BWP).

[0108] 16. The method according to any one of the preceding clauses, wherein the timing offset is less than a threshold, and the method further includes adjusting the timing parameter according to the timing offset and the transmission mode, the timing offset being between high-priority grant-free transmission and low-priority transmission.

[0109] 17. The method according to any one of the preceding clauses further includes:

[0110] setting the timing parameter by measuring the source reference signal indicated by the uplink TCI state; and

[0111] the adjustment further includes adjusting all uplink beams using a single timing adjustment based on the measurement of the source reference signal.

[0112] 18. An apparatus for a UE (user equipment) for wireless communication, including:

[0113] a memory, and

[0114] at least one processor operatively coupled to the memory, the memory and the at least one processor being configured to:

[0115] set a timing parameter based on an uplink TCI (transmission configuration indication) state; and

[0116] Adjust the uplink transmission timing for uplink transmission based on the timing parameter.

[0117] 19. The apparatus according to clause 18, wherein the at least one processor is further configured to: set the timing parameter based on a quasi - co - located (QCL) source reference signal (RS) specified by the uplink TCI state.

[0118] 20. The apparatus according to clause 18 or 19, wherein the QCL source reference signal includes SRS in a configured set of SRS (sounding reference signal) resources, and wherein the at least one processor is further configured to set the timing parameter by: setting the timing parameter to match the timing advance of the SRS resource set.

[0119] 21. The apparatus according to any one of clauses 18 - 20, wherein the at least one processor is further configured to set the timing parameter by: setting the timing parameter by calculating a beam - specific timing advance, wherein the QCL source reference signal includes a downlink reference signal, and the downlink reference signal includes a TRS (tracking reference signal), an SSB (synchronization signal block), or a CSI - RS (channel state information reference signal).

[0120] 22. The apparatus according to any one of clauses 18 - 21, wherein the at least one processor is further configured to: adjust the uplink transmission timing for multiple uplink beams, each uplink beam having its own uplink TCI state.

[0121] 23. The apparatus according to any one of clauses 18 - 22, wherein the at least one processor is further configured to: indicate the maximum number of sub - timing advance groups (TAGs) supported by the UE.

[0122] 24. The apparatus according to any one of clauses 18 - 23, wherein the at least one processor is further configured to:

[0123] set the timing parameter by measuring the source reference signal indicated by the uplink TCI state; and

[0124] adjust by: using a single timing adjustment based on the measurement of the source reference signal to adjust all uplink beams.

[0125] 25. An apparatus for a base station for wireless communication, comprising:

[0126] a memory, and

[0127] At least one processor operatively coupled to the memory, the memory and the at least one processor being configured to:

[0128] Set timing parameters for a user equipment (UE) based on an uplink TCI (transmission configuration indication) state; and adjust an uplink transmission timing for uplink transmission based on the timing parameters.

[0129] 26. The apparatus according to clause 25, wherein the at least one processor is configured to: receive an indication of a maximum number of sub-timing advance groups (TAGs) supported by the UE from the UE before setting the timing parameters.

[0130] 27. The apparatus according to clause 25 or 26, wherein the at least one processor is configured to: send an indication of the number of sub-timing advance groups (TAGs) to be supported.

[0131] 28. The apparatus according to any one of clauses 25-27, wherein the at least one processor is configured to: send a timing advance command including at least one sub-timing advance group (TAG) index, each sub-TAG including at least one uplink TCI state.

[0132] 29. The apparatus according to any one of clauses 25-28, wherein the at least one processor is configured to: send a media access control-control element (MAC-CE) including updates of a plurality of sub-timing advance groups (TAGs).

[0133] 30. A user equipment (UE) for wireless communication, comprising: units for performing the method according to any one of clauses 1 to 17.

[0134] 31. A non-transitory computer-readable medium storing code for wireless communication, the code including instructions executable by a processor to perform the method according to any one of clauses 1 to 17.

[0135] The foregoing disclosure provides illustration and description, but is not intended to be exhaustive or to limit aspects to the precise forms disclosed. Modifications and variations may be made in accordance with the foregoing disclosure, or may be obtained from practice of the aspects.

[0136] As used, the term "component" is intended to be broadly construed as hardware, firmware, and / or a combination of hardware and software. As used, a processor is implemented in hardware, firmware, and / or a combination of hardware and software.

[0137] Some aspects are described in connection with a threshold. As used, depending on the context, meeting the threshold can refer to a value being greater than the threshold, greater than or equal to the threshold, less than the threshold, less than or equal to the threshold, equal to the threshold, not equal to the threshold, etc.

[0138] It will be apparent that the described systems and / or methods can be implemented in various forms of hardware, firmware, and / or combinations of hardware and software. The actual specific control hardware or software code used to implement these systems and / or methods does not limit the aspects. Thus, without reference to specific software code, the operations and behaviors of the systems and / or methods are described, understanding that software and hardware can be designed to implement the systems and / or methods at least in part based on the description.

[0139] Even if specific combinations of features are recited in the claims and / or disclosed in the specification, these combinations are not intended to limit the disclosure of the various aspects. In fact, many of these features can be combined in ways not specifically recited in the claims and / or specifically disclosed in the specification. While each dependent claim listed below may directly depend on only one claim, the disclosure of the various aspects includes the combination of each dependent claim with every other claim in the set of claims. The phrase referring to a list of items “at least one of” refers to any combination of those items, including a single member. By way of example, “at least one of a, b, or c” is intended to cover a, b, c, a - b, a - c, b - c, and a - b - c, as well as any combination of multiples of the same elements (e.g., a - a, a - a - a, a - a - b, a - a - c, a - b - b, a - c - c, b - b, b - b - b, b - b - c, c - c, and c - c - c, or any other ordering of a, b, and c).

[0140] None of the elements, acts, or instructions used should be construed as critical or essential unless expressly described as such. Further, as used, the articles “a” and “an” are intended to include one or more items and can be used interchangeably with “one or more.” Additionally, as used herein, the terms “set” and “group” are intended to include one or more items (e.g., related items, unrelated items, combinations of related and unrelated items, etc.) and can be used interchangeably with “one or more.” Where only one item is intended, the phrase “only one” or similar language is used. Further, as used, the terms “has,” “have,” “having,” etc. are intended to be open - ended terms. Additionally, unless otherwise expressly stated, the phrase “based on” is intended to mean “at least partially based on.”

Claims

1. A method for wireless communication by a UE (User Equipment), comprising: Setting a timing advance parameter for a timing advance group (TAG) of the UE based on a quasi - co - located (QCL) source reference signal (RS) indicated by an uplink TCI (Transmission Configuration Indication) state, the QCL source RS being from a configured resource set; And Adjusting an uplink transmission timing for uplink transmission based on the timing advance parameter for the TAG of the UE, the timing advance parameter being based on the QCL source RS indicated by the uplink TCI state.

2. The method according to claim 1, wherein The QCL source reference signal includes SRS (Sounding Reference Signal) in a configured set of SRS resources, and wherein setting the timing advance parameter includes setting the timing advance parameter to match the timing advance of the SRS resource set.

3. The method according to claim 1, wherein Setting the timing advance parameter includes setting the timing advance parameter by calculating a beam - specific timing advance, wherein the QCL source reference signal includes a downlink reference signal, and the downlink reference signal includes a TRS (Tracking Reference Signal), an SSB (Synchronization Signal Block), or a CSI - RS (Channel State Information Reference Signal).

4. The method according to claim 1 further comprises: Adjusting the uplink transmission timing for multiple uplink beams, each uplink beam having its own uplink TCI state.

5. The method according to claim 1 further comprises: Indicating a maximum number of sub - timing advance groups (TAGs) supported by the UE.

6. The method according to claim 1 further comprises: Receiving an indication of the number of sub - timing advance groups (TAGs) to be supported.

7. The method according to claim 1, wherein, The timing advance command includes at least one sub - timing advance group (TAG) index, and each sub - TAG includes at least one uplink TCI state.

8. The method according to claim 1, wherein The Medium Access Control - Control Element (MAC - CE) includes multiple sub - timing advance group (TAG) updates.

9. The method according to claim 1, further comprising: Receiving an indication of a timing reference RS (Reference Signal); Deriving a timing estimate for the timing reference RS; And Adjusting the timing advance parameter based on the timing estimate.

10. The method according to claim 1 further comprises: Adjusting the timing based on a time tracking loop or channel power delay profile estimate of a TRS (Tracking Reference Signal) that is spatially quasi - co - located with a source downlink RS, the source downlink RS being quasi - co - located with the uplink transmission.

11. The method according to claim 1 further comprises: When the source reference signal is not a tracking reference signal, or the source reference signal is an SRS (Sounding Reference Signal) that is spatially quasi - co - located with the uplink transmission and the SRS is not configured with spatial relationship information, calculating the timing adjustment based on a timing estimate of at least one downlink reference signal.

12. The method according to claim 11, wherein, The calculation is based on the minimum value of the timing estimates from multiple downlink reference signals or the average value of the timing estimates of the multiple downlink reference signals.

13. The method according to claim 1 further comprises: Adjusting the uplink timing for a Physical Uplink Shared Channel (PUSCH) based on a parameter different from the parameter used to adjust the timing for a Physical Uplink Control Channel (PUCCH), wherein the TCI state for the PUCCH is different from the TCI state for the PUSCH.

14. The method according to claim 1 further comprises: Continue to apply the adjusted uplink transmission timing during a time period after switching a bandwidth part (BWP).

15. The method according to claim 1, wherein The timing offset is less than a threshold, and the method further includes adjusting the timing advance parameter according to the timing offset and a transmission mode, the timing offset being between a high-priority grant-free transmission and a low-priority transmission.

16. The method according to claim 1, further comprising: Setting the timing advance parameter by measuring the source reference signal indicated by the uplink TCI state; And The adjustment further includes adjusting all uplink beams by using a single timing adjustment based on the measurement of the source reference signal.

17. An apparatus for a UE (user equipment) for wireless communication, comprising: A memory, and At least one processor operatively coupled to the memory, the memory and the at least one processor being configured to: Set a timing advance parameter for a timing advance group (TAG) of the UE based on a quasi-co-located (QCL) source reference signal (RS) indicated by an uplink TCI (transmission configuration indicator) state, the QCL source RS being from a configured resource set; And Adjust an uplink transmission timing for uplink transmission based on the timing advance parameter of the TAG for the UE, the timing advance parameter being based on the QCL source RS indicated by the uplink TCI state.

18. The apparatus according to claim 17, wherein, The QCL source reference signal includes SRS in a configured set of SRS (sounding reference signal) resources, and wherein the at least one processor is further configured to set the timing advance parameter by: setting the timing advance parameter to match the timing advance of the SRS resource set.

19. The apparatus according to claim 17, wherein, The at least one processor is further configured to set the timing advance parameter by calculating a beam-specific timing advance, wherein the QCL source reference signal includes a downlink reference signal, the downlink reference signal including a TRS (tracking reference signal), an SSB (synchronization signal block), or a CSI-RS (channel state information reference signal).

20. The apparatus according to claim 17, wherein The at least one processor is further configured to: adjust an uplink transmission timing for a plurality of uplink beams, each uplink beam having its own uplink TCI state.

21. The device according to claim 17, wherein, The at least one processor is further configured to: indicate a maximum number of sub-timing advance groups (TAGs) supported by the UE.

22. The device according to claim 17, wherein, The at least one processor is further configured to: Set the timing advance parameter by measuring the source reference signal indicated by the uplink TCI state; and Perform the adjustment by: adjusting all uplink beams by using a single timing adjustment based on the measurement of the source reference signal.

23. An apparatus for a base station for wireless communication, comprising: A memory, and At least one processor operatively coupled to the memory, the memory and the at least one processor being configured to: Set timing advance parameters for a timing advance group (TAG) for a user equipment (UE) based on a quasi - co - located (QCL) source reference signal (RS) indicated by an uplink TCI (transmission configuration indication) state, where the QCL source RS is from a configured resource set; And Adjust the uplink transmission timing for uplink transmission based on the timing advance parameters for the TAG of the UE, where the timing advance parameters are based on the QCL source RS indicated by the uplink TCI state.

24. The device according to claim 23, wherein, The at least one processor is configured to: receive an indication of the maximum number of sub - timing advance groups (TAGs) supported by the UE from the UE before setting the timing advance parameters.

25. The device according to claim 23, wherein The at least one processor is configured to: send an indication of the number of sub - timing advance groups (TAGs) to be supported.

26. The apparatus according to claim 23, wherein, The at least one processor is configured to: send a timing advance command including at least one sub - timing advance group (TAG) index, where each sub - TAG includes at least one uplink TCI state.

27. The device according to claim 23, wherein The at least one processor is configured to: send a media access control - control element (MAC - CE) including multiple sub - timing advance group (TAG) updates.

28. A user equipment (UE) for wireless communication, comprising: A unit for setting timing advance parameters for a timing advance group (TAG) for the UE based on a quasi - co - located (QCL) source reference signal (RS) indicated by an uplink TCI (transmission configuration indication) state, where the QCL source RS is from a configured resource set; And A unit for adjusting the uplink transmission timing for uplink transmission based on the timing advance parameters for the TAG of the UE, where the timing advance parameters are based on the QCL source RS indicated by the uplink TCI state.

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