Method and apparatus for obtaining time alignment for multiple transmits points

Abstract

Methods, systems, and devices are provided for enhancing timing alignment for uplink multi-transmission point scenarios in wireless communication systems. A method for a user equipment in a wireless communication system can include receiving signaling, where the signaling indicates an activation of a first transmission point and / or a physical downlink control channel signal; determining, based on the signaling, to perform a first random access procedure on the first transmission point to obtain first time alignment information associated with the first transmission point; and performing a multi-transmission point operation on the first transmission point associated with the first time alignment information and a second transmission point associated with second time alignment information.

Description

Technical Field

[0001] This disclosure generally relates to wireless communication networks, and more specifically, to methods and apparatus for enhancing timing alignment in uplink (UL) multiple transceiver point (TRP) (or mTRP) scenarios in wireless communication systems. Background Technology

[0002] With the rapid growth in demand for transmitting large amounts of data to and from mobile communication devices, traditional mobile voice communication networks have evolved into networks that communicate with Internet Protocol (IP) packets. This type of IP packet communication can provide users of mobile communication devices with IP-bearing voice, multimedia, multicast, and video-on-demand communication services.

[0003] An exemplary network architecture is the Evolved Universal Terrestrial Radio Access Network (E-UTRAN). E-UTRAN systems can provide high data throughput to enable the aforementioned IP-based voice and multimedia services. Currently, the 3rd Generation Partnership Project (3GPP) standards organization is discussing new next-generation (e.g., 5G) radio technologies. Therefore, changes to the current body of the 3GPP standards are being submitted and considered to evolve and finalize the 3GPP standards. Summary of the Invention

[0004] Methods, systems, and apparatus are provided for enhancing timing alignment in uplink (UL) multiple transceiver point (TRP) (or mTRP) scenarios in wireless communication systems.

[0005] In various embodiments, according to this and other concepts, systems, and methods of the present invention, a method for a UE in a wireless communication system includes: receiving signaling, wherein the signaling indicates the activation of a first transceiver point (TRP) and / or a physical downlink control channel (PDCCH) signal; determining, based on the signaling, to perform a first random access procedure on the first TRP to obtain first time alignment (TA) information associated with the first TRP; and performing multiple TRP operations on the first TRP associated with the first TA information and a second TRP associated with second TA information. Attached Figure Description

[0006] Figure 1 A diagram illustrating a wireless communication system according to an embodiment of the present invention;

[0007] Figure 2This is a block diagram of a transmitter system (also referred to as an access network) and a receiver system (also referred to as a user equipment or UE) according to an embodiment of the present invention;

[0008] Figure 3 This is a functional block diagram of a communication system according to an embodiment of the present invention;

[0009] Figure 4 This is according to an embodiment of the present invention. Figure 3 Functional block diagram of the program code;

[0010] Figure 5 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.4-1: Timing Advancement Command MAC CE;

[0011] Figure 6 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.4a-1: Absolute Timing Advance Command (MACCE);

[0012] Figure 7 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.15-1: TCI status indication for UE-specific PDCCH MACCE;

[0013] Figure 8 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.14-1: TCI state activation / deactivation for UE-specific PDSCH MACCE;

[0014] Figure 9 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.24-1: Enhanced TCI state activation / deactivation for UE-specific PDSCH MACCE;

[0015] Figure 10 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.25-1: Enhanced PUCCH spatial relation activation / deactivation MAC CE;

[0016] Figure 11 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.26-1: Enhanced SP / AP SRS spatial relationship indicator MAC CE;

[0017] Figure 12 For 3GPP TS 38.211, V16.6.0 Figure 4 Reproduction of .3.1-1: Uplink-Downlink Timing Relationship;

[0018] Figure 13 This is an example of an extended TAC MAC CE according to an embodiment of the present invention;

[0019] Figure 14A and Figure 14B This is an example of an extended TAC MAC CE for a non-serving cell according to an embodiment of the present invention;

[0020] Figure 15A This is another example of an extended TAC MAC CE according to an embodiment of the present invention;

[0021] Figure 15B According to an embodiment of the present invention, the MAC CE may contain a non-serving cell ID and the UE applies Offset1 or TAC_TRP2 to a non-serving cell associated with non-serving cell ID1;

[0022] Figure 15C According to an embodiment of the present invention, the MAC CE may contain one or more instances of offset or TAC for non-serving cells;

[0023] Figure 15D According to an embodiment of the present invention, the MAC CE may contain one or more instances of offset or TAC for non-serving cells;

[0024] Figure 16 A flowchart illustrating a method for a UE to receive configuration of UL resources associated with a first TRP and UL resources associated with a second TRP from a network, according to an embodiment of the present invention.

[0025] Figure 17 A flowchart illustrating a method for a UE to perform UL transmission on a first TRP and a second TRP according to an embodiment of the present invention;

[0026] Figure 18 A flowchart illustrating a method for a UE to perform inter-cell mTRP operations on serving and non-serving cells according to an embodiment of the present invention;

[0027] Figure 19 A flowchart illustrating a method for configuring UL resources associated with a first TRP and UL resources associated with a second TRP for a UE in a network according to an embodiment of the present invention;

[0028] Figure 20A flowchart illustrating a method for a UE to receive configuration of UL resources associated with a first TRP and UL resources associated with a second TRP from a network, according to an embodiment of the present invention.

[0029] Figure 21 This is a flowchart of a method for a UE to receive signaling according to an embodiment of the present invention, wherein the signaling indicates the activation of a first TRP and / or is a PDCCH signal. Detailed Implementation

[0030] The invention described herein can be applied to or implemented in the exemplary wireless communication systems and apparatus described below. Furthermore, the invention is primarily described in the context of the 3GPP architecture reference model. However, it should be understood that, with the aid of the disclosed information, those skilled in the art can readily adapt it to use and implement aspects of the invention in 3GPP2 network architectures and other network architectures.

[0031] The exemplary wireless communication systems and apparatus described below employ wireless communication systems that support broadcast services. Wireless communication systems are widely deployed to provide various types of communication, such as voice and data. These systems may be based on Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Orthogonal Frequency Division Multiple Access (OFDMA), 3GPP Long Term Evolution (LTE) radio access, 3GPP Long Term Evolution Advanced (LTE-A) radio access, 3GPP2 Ultra Mobile Broadband (UMB), World Interoperability for Microwave Access (WiMax), 3GPP New Radio (NR), or some other modulation techniques.

[0032] Specifically, the exemplary wireless communication systems and apparatus described below may be designed to support one or more standards, such as those provided by the association known herein as 3GPP, which is called the “3rd Generation Partnership Project”, including: [1] RP-193133 New WID: Further Enhancements to MIMO for NR; [2] 3GPP TS 38.213, V16.6.0; [3] 3GPP TS 38.321, V16.5.0; [4] 3GPP TS 38.331, V16.5.0; [5] 3GPP TS 38.211, V16.6.0; and [6] 3GPP TS 38.212, V16.6.0. The standards and documents listed above are hereby explicitly and entirely incorporated herein by reference in their entirety.

[0033] Figure 1 A multiple access wireless communication system according to an embodiment of the present invention is illustrated. Access network 100 (AN) includes multiple antenna groups, one group comprising 104 and 106, another group comprising 108 and 110, and an additional group comprising 112 and 114. Figure 1 In this diagram, only two antennas are shown in each antenna group; however, each antenna group may utilize more or fewer antennas. Access terminal (AT) 116 communicates with antennas 112 and 114, which transmit information to AT 116 on forward link 120 and receive information from AT 116 on reverse link 118. AT 122 communicates with antennas 106 and 108, which transmit information to AT 122 via forward link 126 and receive information from AT 122 via reverse link 124. In a Frequency Division Duplex (FDD) system, communication links 118, 120, 124, and 126 may use different frequencies for communication. For example, forward link 120 may use a different frequency than that used by reverse link 118.

[0034] Each antenna group and / or the area in which the antenna groups are designed to communicate is often referred to as a sector of the access network. In an embodiment, each antenna group is designed to communicate with an access terminal in a sector of an area covered by access network 100.

[0035] In communications via forward links 120 and 126, the transmit antennas of access network 100 can utilize beamforming to improve the signal-to-noise ratio of the forward links used for different access terminals 116 and 122. Furthermore, compared to an access network transmitting to all its access terminals via a single antenna, using beamforming to transmit to access terminals randomly distributed within its coverage area causes less interference to access terminals in neighboring cells.

[0036] AN can be a fixed station or base station used for communication with terminals, and may also be referred to as an access point, node B, base station, enhanced base station, eNodeB, or other terminology. AT may also be referred to as user equipment (UE), wireless communication device, terminal, access terminal, or other terminology.

[0037] Figure 2This is a simplified block diagram of an embodiment of a Multiple Input Multiple Output (MIMO) system 200, comprising a transmitter system 210 (also referred to as an access network) and a receiver system 250 (also referred to as an access terminal (AT) or user equipment (UE)). At the transmitter system 210, service data for multiple data streams is provided from a data source 212 to a transport (TX) data processor 214.

[0038] In one embodiment, each data stream is transmitted via a corresponding transmit antenna. The TX data processor 214 formats, encodes, and interleaves the service data of each data stream based on a specific encoding scheme selected for the data stream to provide encoded data.

[0039] OFDM technology can be used to multiplex the encoded data and pilot data of each data stream. The pilot data is typically a known data pattern processed in a known manner and can be used at the receiver system to estimate the channel response. The multiplexed pilot and encoded data of each data stream are then modulated (e.g., symbol mapped) based on a specific modulation scheme selected for the data stream (e.g., Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), Multiple Phase Shift Keying (M-PSK), or Quadrature Amplitude Modulation (M-QAM)). The data rate, encoding, and modulation of each data stream can be determined by instructions executed by processor 230.

[0040] The modulation symbols of all data streams are then provided to the TX MIMO processor 220, which can further process the modulation symbols (e.g., for OFDM). The TX MIMO processor 220 then... T A modulation symbol stream is provided to N T Transmitters (TMTRs) 222a to 222t. In some embodiments, the TX MIMO processor 220 applies beamforming weights to the symbols of the data stream and to the antennas transmitting symbols from it.

[0041] Each transmitter 222 receives and processes a corresponding symbol stream to provide one or more analog signals, and further modulates (e.g., amplifies, filters, and upconverts) the analog signals to provide modulated signals suitable for transmission over a MIMO channel. Subsequently, from N... T Antennas 224a to 224t transmit N from transmitters 222a to 222t.T A modulated signal.

[0042] At receiver system 250, by N R Each antenna 252a to 252r receives the transmitted modulated signal and provides the signal received from each antenna 252 to a corresponding receiver (RCVR) 254a to 254r. Each receiver 254 modulates (e.g., filters, amplifies, and down-converts) the corresponding received signal, digitizes the modulated signal to obtain a sample, and further processes the sample to obtain the corresponding "received" symbol stream.

[0043] The RX data processor 260 then receives and processes data from N based on specific receiver processing technology. R N received by 254 receivers R A symbol stream to obtain N T Each detected symbol stream is then demodulated, deinterleaved, and decoded by the RX data processor 260 to recover the service data of the data stream. The processing performed by the RX data processor 260 is complementary to the processing performed by the TX MIMO processor 220 and TX data processor 214 at the transmitter system 210.

[0044] Processor 270 periodically determines which precoding matrix to use (discussed below). Processor 270 formulates a reverse link message that includes the matrix index portion and the rank portion.

[0045] The reverse link message may include various types of information about the communication link and / or the received data streams. The reverse link message is then processed by the TX data processor 238, which also receives service data from several data streams from the data source 236, modulated by the modulator 280, regulated by the transmitters 254a to 254r, and transmitted back to the transmitter system 210.

[0046] At transmitter system 210, the modulated signal from receiver system 250 is received by antenna 224, conditioned by receiver 222, demodulated by demodulator 240, and processed by RX data processor 242 to extract the reverse link message transmitted by receiver system 250. Processor 230 then determines which precoding matrix to use to determine beamforming weights and then processes the extracted message.

[0047] Memory 232 can be used to temporarily store some buffered / calculated data from processor 240 or 242 via processor 230, some buffered data from processor 212, or some specific program code. Furthermore, memory 272 can be used to temporarily store some buffered / calculated data from processor 260 via processor 270, some buffered data from processor 236, or some specific program code.

[0048] Turning Figure 3 This figure illustrates an alternative simplified functional block diagram of a communication device according to an embodiment of the present invention. Figure 3 As shown, the communication device 300 in the wireless communication system can be used to implement Figure 1 The UE (or AT) 116 and 122 are used, and the wireless communication system is preferably an NR system. The communication device 300 may include an input device 302, an output device 304, a control circuit 306, a central processing unit (CPU) 308, a memory 310, program code 312, and a transceiver 314. The control circuit 306 executes the program code 312 in the memory 310 via the CPU 308, thereby controlling the operation of the communication device 300. The communication device 300 can receive signals input by a user via the input device 302 (e.g., a keyboard or keypad) and can output images and sounds via the output device 304 (e.g., a display or speaker). The transceiver 314 is used to receive and transmit wireless signals, transmit the received signals to the control circuit 306, and wirelessly output signals generated by the control circuit 306.

[0049] Figure 4 According to an embodiment of the present invention Figure 3 The diagram shows a simplified block diagram of program code 312. In this embodiment, program code 312 includes an application layer 400, a layer 3 portion 402, and a layer 2 portion 404, and is coupled to a layer 1 portion 406. Layer 3 portion 402 typically performs radio resource control. Layer 2 portion 404 typically performs link control. Layer 1 portion 406 typically performs physical connections.

[0050] For LTE, LTE-A, or NR systems, Layer 2, Part 404 may include a Radio Link Control (RLC) layer and a Medium Access Control (MAC) layer. Layer 3, Part 402 may include a Radio Resource Control (RRC) layer.

[0051] Any two or more of the following paragraphs, (sub)bullets, points, actions, or claims described in each invention may be logically, reasonably, and appropriately combined to form a particular method.

[0052] Any sentence, paragraph, (sub)bullet, point, action, or claim described in each of the following inventions may be implemented independently and separately to form a particular method or apparatus. The use of terms such as "based on," "more precisely," and "example" in the following disclosure is merely to suggest one possible embodiment of the particular method or apparatus and does not limit its application.

[0053] In the description of the work item for further enhancement of MIMO for NR ([1] RP-193133 New WID: Further Enhancement of MIMO for NR), beam management considering multi-TRP / panel operation is considered as one of the following objectives:

[0054] 3 Adjustments

[0055] Rel-15NR includes several MIMO features that facilitate the utilization of a large number of antenna elements at the base station in both sub-6 GHz and above 6 GHz bands. Rel-16NR enhances Rel-15 by introducing: an enhanced Type II codebook with DFT-based compression; support for multi-TRP transmission specifically for eMBB and PDSCH; enhancements for multi-beam operation including reduced latency and / or overhead for various reconfigurations (QCL-related measurements); SCell beam fault recovery (BFR); and L1-SINR. Additionally, a low PAPR reference signal and features are introduced to enable full-power uplink transmission.

[0056] As NR becomes commercialized, various aspects requiring further enhancement can be identified from real-world deployment scenarios. These aspects include the following: First, while Rel-16 provides some reductions in overhead and / or latency, greater reductions in latency and overhead are needed in high-speed vehicle scenarios under FR2 (e.g., UEs traveling at high speeds on highways)—not only intra-cell but also for L1 / L2 inter-cell mobility. This also includes reducing the occurrence of beam failure events. Second, while enhancements for achieving panel-specific UL beam selection have been investigated in Rel-16, sufficient time has been allocated to complete this work. This presents a possibility for increasing UL coverage, including, for example, reducing UL coverage loss by meeting maximum permissible exposure (MPE) rules. It should be noted that MPE issues can occur on all transmit beams from the panel; therefore, solutions for MPE mitigation can be implemented solely on a panel-by-pane basis to meet regulatory requirements for the scenario of concern.

[0057] Third, channels other than PDSCH can benefit from multi-TRP transmission (and multi-panel reception), which also includes multi-TRP for inter-cell operations. This includes some new use cases for multi-TRP, such as dense UL deployments within macrocells and / or heterogeneous network deployment scenarios. Fourth, due to the use of SRS for various scenarios, SRS can and should be further enhanced, at least for capacity and coverage. Fifth, while Rel-16 supports Enhanced Type II CSI, there is room for further enhancements. This includes CSI designed for multi-TRP / panel use cases in NC-JT scenarios and the utilization of partial reciprocity in channel statistics, such as angle and delay primarily for FR1FDD deployments.

[0058] 4 objectives

[0059] 4.1 Target of SI or core WI or test WI

[0060] The work item aims to specify further enhancements for NR MIMO identification. Detailed objectives are as follows:

[0061] - Extend specification support for the following domains [RAN1]

[0062] 1. Enhancements to multi-beam operation, primarily for FR2, but also applicable to FR1:

[0063] a. Identify and specify characteristics to facilitate more efficient (lower latency and overhead) DL / UL beam management to support higher intra-cell and L1 / L2 inter-cell mobility and / or a large number of configured TCI states:

[0064] i. Common beam for data and control transmission / reception in DL and UL, especially for in-band CA

[0065] ii. Unified TCI framework for DL ​​and UL beam indication

[0066] iii. Enhancements to the signaling mechanisms used for the above features to improve latency and efficiency, and increased use of dynamic control signaling (as opposed to RRC).

[0067] b. To mitigate UL coverage loss caused by MPE, UL beam indication, identification, and designation features are based on a unified TCI framework for UL rapid panel selection to facilitate UL beam selection for UEs equipped with multiple panels.

[0068] 2. Enhanced support for multi-TRP deployments, for both FR1 and FR2:

[0069] a. Identify and specify features to improve the reliability and stability of channels other than PDSCH (i.e., PDCCH, PUSCH, and PUCCH) using multiple TRPs and / or multiple panels, with Rel.16 reliability features as the baseline.

[0070] b. Assuming multi-DCI-based multi-PDSCH reception, identify and specify QCL / TCI-related enhancements to enable inter-cell multi-TRP operations.

[0071] c. Evaluate and (if necessary) specify beam management-related enhancements for simultaneous multi-TRP transmission and multi-panel reception.

[0072] In 3GPP specification 38.213[2], timing adjustments for UL transmission are introduced:

[0073] 4.2 Transmission Timing Adjustment

[0074] The timing advance offset value N of the serving cell can be provided to the UE through the n-TimingAdvanceOffset of the serving cell. TA,offset If the UE is not provided with an n-TimingAdvanceOffset for the serving cell, then the UE determines a default value N for the timing advance offset used for the serving cell. TA,offset As described in [10, TS 38.133].

[0075] If the UE is configured with two UL carriers for the serving cell, then the same timing advance offset value N TA,offset This applies to both carriers.

[0076] After receiving the timing advance command for TAG, the UE determines the value N based on its expectation that the value is the same for all serving cells in the TAG. TA,offset Furthermore, based on the received timing advance command, the uplink timing of PUSCH / SRS / PUCCH transmission on all serving cells in the TAG is adjusted, wherein the uplink timing of PUSCH / SRS / PUCCH transmission is the same for all serving cells in the TAG.

[0077] In the case of random access response or in absolute timing advance command MAC CE, the timing advance command for TAG [11, TS 38.321], T A By index value T A =0, 1, 2, ..., 3846 indicates N TA Values, where the value is 2 in SCS. μ At 15kHz, the time alignment amount used for TAG is N. TA =T A ·16·64 / 2μ After receiving a random access response or absolute timing advance command (MAC CE), N is defined in [4, TS 38.211]. TA And it relates to the SCS transmitted from the first uplink of the UE.

[0078] In other cases, the timing advance command [11,TS 38.321] used for TAG, T A By index value T A =0, 1, 2, ..., 63 indicates the current N TA Value N TA_old To New N TA Value N TA _ new The adjustment, of which for 2 μ ·15kHz SCS, N TA_new =N TA_old +(T A -31)·16·64 / 2 μ .

[0079] N TA The positive or negative value adjustment indicates whether the uplink transmission timing of the TAG is advanced or delayed by the corresponding amount.

[0080] If, without a timing advance command, the received downlink timing change is not compensated or only partially compensated for by the uplink timing adjustment, as described in [10, TS 38.133], then the UE accordingly changes N. TA .

[0081] In 3GPP specification 38.321[3], random access procedures and TA maintenance are introduced:

[0082] 5.1 Random Access Procedure

[0083] 5.1.1 Random Access Program Initialization

[0084] According to TS 38.300[2], the random access procedure described in this clause is initiated by a PDCCH command, the MAC entity itself, or an RRC of an event. In a MAC entity, there is only one random access procedure in progress at any given time. The random access procedure on the SCell will be initiated only by a PDCCH command where ra-PreambleIndex is different from 0b000000.

[0085] 5.1.3 Random Access Preamble Transmission

[0086] For each random access preamble, the MAC entity will:

[0087] 1> If PREAMBLE_TRANSMISSION_COUNTER is greater than one; and

[0088] 1> If a notification to pause the power uniformity counter has not yet been received from the lower layer; and

[0089] 1> If no LBT fault indication is received from the lower layer for the last random access preamble transmission; and

[0090] 1> If the selected SSB or CSI-RS has not been changed from the selection in the last random access preamble transmission, then:

[0091] 2> Increase PREAMBLE_POWER_RAMPING_COUNTER by 1.

[0092] 1> Select the value of DELTA_PREAMBLE according to clause 7.3;

[0093] 1>Set PREAMBLE_RECEIVED_TARGET_POWER to preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP+POWER_OFFSET_2STEP_RA;

[0094] 1> Except for the contention-free random access preamble used for beam fault recovery requests, calculate the RA-RNTI associated with the PRACH timing in which the random access preamble is transmitted.

[0095] 1> Instruct the physical layer to use the selected PRACH timing, the corresponding RA-RNTI (if available), PREAMBLE_INDEX, and PREAMBLE_RECEIVED_TARGET_POWER to transmit the random access preamble.

[0096] 5.1.3a MSGA Transfer

[0097] For each MSGA, the MAC entity will:

[0098] 1> If PREAMBLE_TRANSMISSION_COUNTER is greater than one; and

[0099] 1> If a notification to pause the power uniformity counter has not yet been received from the lower layer; and

[0100] 1> If no LBT fault indication is received from the lower layer for the last MSGA random access preamble transmission; and

[0101] 1> If the selected SSB has not changed from the selection in the last random access preamble transmission, then:

[0102] 2> Increase PREAMBLE_POWER_RAMPING_COUNTER by 1.

[0103] 1> Select the value of DELTA_PREAMBLE according to clause 7.3;

[0104] 1>Set PREAMBLE_RECEIVED_TARGET_POWER to preambleReceivedTargetPower+DELTA_PREAMBLE+(PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP;

[0105] 1> If this is the first MSGA transfer within this random access procedure:

[0106] 2> If no transmission is made for the CCCH logical channel, then:

[0107] 3> The multiplexing and aggregation entity indication includes C-RNTI MAC CE in subsequent uplink transmissions.

[0108] 2> If a random access procedure is initiated for SpCell beam fault recovery and spCell-BFR-CBRA with a true value is configured:

[0109] 3> Indicate to the multiplexing and aggregation entity that a BFR MAC CE or a truncated BFR MAC CE is included in subsequent uplink transmissions.

[0110] 2> Based on the HARQ information determined for the MSGA payload (see Clause 5.1.2a), obtain the MAC PDU to be transmitted from the multiplexing and aggregation entity and store it in the MSGA buffer.

[0111] 1> Calculate the MSGB-RNTI associated with the PRACH timing in which the random access preamble is transmitted;

[0112] 1> Instruct the physical layer to use the selected PRACH timing and the associated PUSCH resources of the MSGA (if the selected preamble and PRACH timing are mapped to a valid PUSCH timing), and to use the corresponding RA-RNTI, MSGB-RNTI, PREAMBLE_INDEX, PREAMBLE_RECEIVED_TARGET_POWER, msgA-PreambleReceivedTargetPower, and apply power uniformly to the latest MSGA preamble transmission (i.e., (PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP) to transmit the MSGA;

[0113] 5.1.4 Random Access Response Reception

[0114] Once the random access preamble is transmitted, regardless of whether a measurement gap is possible, the MAC entity will:

[0115] 1> If the contention-free random access preamble used for beam fault recovery requests is transmitted by the MAC entity, then:

[0116] 2>Start the ra-ResponseWindow configured in BeamFailureRecoveryConfig at the first PDCCH timing specified in TS 38.213[6] from the end of the random access preamble transmission;

[0117] 2> While ra-ResponseWindow is running, listen for PDCCH transmissions on the search space indicated by the recoverySearchSpaceId of the SpCell identified by C-RNTI.

[0118] 1> Otherwise:

[0119] 2>Start the ra-ResponseWindow configured in RACH-ConfigCommon at the first PDCCH timing specified in TS 38.213[6] from the end of the random access preamble transmission;

[0120] 2> While ra-ResponseWindow is running, listen for the PDCCH of the SpCell identified by RA-RNTI for random access responses.

[0121] 1> If a lower layer on the serving cell from which the preamble is transmitted receives a notification that a PDCCH transmission has been received in the search space indicated by recoverySearchSpaceId; and

[0122] 1> If the PDCCH transmission is addressed to C-RNTI; and

[0123] 1> If the contention-free random access preamble used for beam fault recovery requests is transmitted by the MAC entity, then:

[0124] 2> The random access procedure is considered to have been successfully completed.

[0125] 1> Otherwise, if a valid downlink assignment (as specified in TS 38.213[6]) has been received on the PDCCH for RA-RNTI, and the received TB has been successfully decoded:

[0126] 2> If the random access response contains a MAC sub-PDU with a backoff indicator, then:

[0127] 3> Use Table 7.2-1 to set PREAMBLE_BACKOFF to the value of the BI field of the MAC sub-PDU by multiplying it by SCALING_FACTOR_BI.

[0128] 2> Otherwise:

[0129] 3> Set PREAMBLE_BACKOFF to 0ms.

[0130] 2> If the random access response contains a MAC sub-PDU with a random access preamble identifier corresponding to the transmitted PREAMBLE_INDEX (see Clause 5.1.3), then:

[0131] 3> This random access response is considered to have been successfully received.

[0132] 2> If the random access response is considered to have been successfully received:

[0133] 3> If the random access response contains a MAC sub-PDU with only RAPID, then:

[0134] 4> This random access procedure is considered to have completed successfully;

[0135] 4> Indicate to the upper layer that an acknowledgment has been received regarding the SI request.

[0136] 3> Otherwise:

[0137] 4> Apply the following actions to the serving cell that transmits the random access preamble:

[0138] 5. Process the received timing advance command (see Clause 5.2);

[0139] 5> Indicate the preambleReceivedTargetPower and the power uniformity applied to the latest random access preamble transmission (i.e., (PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP) to the lower layer;

[0140] 5> If a random access procedure for SCell is performed on an uplink carrier that is not configured with pusch-Config:

[0141] 6> Ignore the received UL approval.

[0142] 5> Otherwise:

[0143] 6> Process the received UL grant value and indicate the value to the lower layer.

[0144] 4> If the MAC entity does not select a random access preamble from the contention-based random access preamble, then:

[0145] 5> The random access procedure is considered to have been successfully completed.

[0146] 4> Otherwise:

[0147] 5> Set TEMPORARY_C-RNTI to the value received in the random access response;

[0148] 5> If this is the first successfully received random access response within this random access procedure:

[0149] 6> If no transmission is made for the CCCH logical channel, then:

[0150] 7> The multiplexing and aggregation entity indication includes C-RNTI MAC CE in subsequent uplink transmissions.

[0151] 6> If a random access procedure is initiated for SpCell beam fault recovery and spCell-BFR-CBRA with a true value is configured:

[0152] 7> Indicate to the multiplexing and aggregation entity that a BFR MAC CE or a truncated BFR MAC CE is included in subsequent uplink transmissions.

[0153] 6> Obtain the MAC PDU to transmit from the multiplexed and aggregated entity and store it in the Msg3 buffer.

[0154] 5.1.4a MSGB reception and contention resolution for 2-step RA type

[0155] Once the MSGA preamble is transmitted, the MAC entity will:

[0156] 1> As specified in TS 38.213[6], Clause 8.2A, the msgB-ResponseWindow is started at the PDCCH timing;

[0157] 1> While msgB-ResponseWindow is running, listen for the PDCCH of the SpCell for random access responses identified by MSGB-RNTI;

[0158] 1> If C-RNTI MAC CE is included in MSGA, then:

[0159] 2> While msgB-ResponseWindow is running, listen for the PDCCH of the SpCell for random access responses identified by C-RNTI.

[0160] 1> If a notification is received from the lower layer that a PDCCH transmission from SpCell has been received:

[0161] 2> If C-RNTI MAC CE is included in MSGA:

[0162] 3> If a random access procedure is initiated for SpCell beam fault recovery (as specified in Clause 5.17) and the PDCCH transmission is addressed to C-RNTI, then:

[0163] 4> This random access response is considered successfully received;

[0164] 4>Stop msgB-ResponseWindow;

[0165] 4> This random access procedure is considered to have been successfully completed.

[0166] 3> Otherwise, if the timeAlignmentTimer associated with PTAG is running:

[0167] 4> If the PDCCH transmission is addressed to C-RNTI and contains UL authorization for the new transmission, then:

[0168] 5> This random access response is considered successfully received;

[0169] 5>Stop msgB-ResponseWindow;

[0170] 5> This random access procedure is considered to have been successfully completed.

[0171] 3> Otherwise:

[0172] 4> If a downlink assignment has been received on the PDCCH of C-RNTI and the received TB has been successfully decoded:

[0173] 5> If the MAC PDU contains the absolute timing advance command MAC CE, then:

[0174] 6> Process the received timing advance command (see Clause 5.2);

[0175] 6> This random access response is considered successfully received;

[0176] 6>Stop msgB-ResponseWindow;

[0177] 6> It is assumed that the random access procedure has successfully completed and ended the decomposition and multiplexing of the MAC PDU.

[0178] 2> If a valid downlink assignment (as specified in TS 38.213[6]) has been received on the PDCCH for MSGB-RNTI, and the received TB has been successfully decoded:

[0179] 3> If MSGB contains a MAC sub-PDU with a backoff indicator:

[0180] 4> Use Table 7.2-1 to set PREAMBLE_BACKOFF to the value of the BI field of the MAC sub-PDU by multiplying it by SCALING_FACTOR_BI.

[0181] 3> Otherwise:

[0182] 4> Set PREAMBLE_BACKOFF to 0ms.

[0183] 3> If MSGB contains a fallbackRAR MAC sub-PDU; and

[0184] 3> If the random access preamble identifier in the MAC sub-PDU matches the transmitted PREAMBLE_INDEX (see Clause 5.1.3a):

[0185] 4> This random access response is considered successfully received;

[0186] 4> Apply the following actions to SpCell:

[0187] 5. Process the received timing advance command (see Clause 5.2);

[0188] 5> Indicate msgA-PreambleReceivedTargetPower and the power uniformity applied to the latest random access preamble transmission (i.e., (PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP) to the lower layer;

[0189] 5> If the MAC entity does not select a random access preamble from the contention-based random access preambles, then:

[0190] 6> The random access procedure is considered to have completed successfully;

[0191] 6> Process the received UL grant value and indicate the value to the lower layer.

[0192] 5> Otherwise:

[0193] 6> Set TEMPORARY_C-RNTI to the value received in the random access response;

[0194] 6> If the Msg3 buffer is empty:

[0195] 7> Obtain the MAC PDU to be transferred from the MSGA buffer and store it in the Msg3 buffer;

[0196] 6> Process the received UL grant value and indicate the value to the lower layer and continue Msg3 transmission.

[0197] 3> Otherwise, if MSGB contains a successRAR MAC sub-PDU; and

[0198] 3> If the CCCH SDU is included in the MSGA, and the UE contention resolution identifier in the MAC sub-PDU matches the CCCHSDU:

[0199] 4>Stop msgB-ResponseWindow;

[0200] 4> If this random access procedure is initiated in response to an SI request, then:

[0201] 5> Indicate to the upper layer that acknowledgment has been received regarding the SI request.

[0202] 4> Otherwise:

[0203] 5> Set C-RNTI to the value received in successRAR;

[0204] 5> Apply the following actions to SpCell:

[0205] 6> Process the received timing advance command (see Clause 5.2);

[0206] 6> Indicate msgA-PreambleReceivedTargetPower and the power uniformity applied to the latest random access preamble transmission (i.e., (PREAMBLE_POWER_RAMPING_COUNTER-1)×PREAMBLE_POWER_RAMPING_STEP) to the lower layer.

[0207] 4> Deliver the TPC, PUCCH resource indicator, channel access-CPext (if indicated), and HARQ feedback timing indicator received in successRAR to the lower layer.

[0208] 4> This random access response is considered successfully received;

[0209] 4> This random access procedure is considered to have completed successfully;

[0210] 4> Complete the decomposition and multiplexing of the MAC PDU.

[0211] 5.1.5 Dispute Resolution

[0212] Once Msg3 is transmitted, the MAC entity will:

[0213] 1> At each HARQ retransmission in the first symbol after Msg3 transmission ends, start and restart ra-ContentionResolutionTimer;

[0214] 1> Regardless of whether a measurement gap is possible, listen to the PDCCH while the ra-ContentionResolutionTimer is running;

[0215] 1> If a notification is received from the lower layer that a PDCCH transmission from SpCell has been received:

[0216] 2> If C-RNTI MAC CE is included in Msg3:

[0217] 3> If a random access procedure is initiated for SpCell beam fault recovery (as specified in Clause 5.17) and the PDCCH transmission is addressed to C-RNTI; or

[0218] 3> If a random access procedure is initiated via a PDCCH command and the PDCCH transmission is addressed to C-RNTI; or

[0219] 3> If a random access procedure is initiated by the MAC sublayer itself or by the RRC sublayer and the PDCCH transmission is addressed to the C-RNTI and contains UL permission for the new transmission, then:

[0220] 4> Consider this dispute resolved successfully;

[0221] 4>Stop ra-ContentionResolutionTimer;

[0222] 4> Discard TEMPORARY_C-RNTI;

[0223] 4> This random access procedure is considered to have been successfully completed.

[0224] 2> Otherwise, if the CCCH SDU is contained in Msg3 and the PDCCH transport is addressed to its TEMPORARY_C-RNTI:

[0225] 3> If the MAC PDU is successfully decoded, then:

[0226] 4>Stop ra-ContentionResolutionTimer;

[0227] 4> If the MAC PDU contains the UE contention resolution identifier MAC CE; and

[0228] 4> If the UE contention resolution identifier in the MAC CE matches the CCCH SDU transmitted in Msg3, then:

[0229] 5> It is considered that this contention has been successfully resolved and the disassembly and multiplexing of the MAC PDU has ended;

[0230] 5> If this random access procedure is initiated in response to an SI request, then:

[0231] 6> Indicate to the upper layer that acknowledgment has been received for the SI request.

[0232] 5> Otherwise:

[0233] 6> Set C-RNTI to the value of TEMPORARY_C-RNTI;

[0234] 5> Discard TEMPORARY_C-RNTI;

[0235] 5> This random access procedure is considered to have been successfully completed.

[0236] 4> Otherwise:

[0237] 5> Discard TEMPORARY_C-RNTI;

[0238] 5> The contention was deemed unsuccessful and the successfully decoded MAC PDU was discarded.

[0239] 5.2 Uplink Time Alignment Maintenance

[0240] The RRC configuration uses the following parameters to maintain UL time alignment:

[0241] -timeAlignmentTimer(per TAG) controls how long the MAC entity considers a serving cell belonging to the associated TAG to need uplink time alignment.

[0242] MAC entities will:

[0243] 1> When the timing advance command MAC CE is received, and if N has been maintained with the indicated TAG, TA (As defined in TS 38.211[8]), then:

[0244] 2> Apply timing advance commands to the indicated TAG;

[0245] 2> Start or restart the timeAlignmentTimer associated with the indicated TAG.

[0246] 1> When a timing advance command is received in a random access response message for a serving cell belonging to a TAG or in an MSGB for SpCell:

[0247] 2> If the MAC entity does not select a random access preamble from the contention-based random access preamble, then:

[0248] 3> Apply timing advance commands to this TAG;

[0249] 3> Start or restart the timeAlignmentTimer associated with this TAG.

[0250] 2> Otherwise, if the timeAlignmentTimer associated with this TAG is not running, then:

[0251] 3> Apply timing advance commands to this TAG;

[0252] 3> Start the timeAlignmentTimer associated with this TAG;

[0253] 3> When dispute resolution is deemed unsuccessful as described in Clause 5.1.5; or

[0254] 3> When, after transmitting HARQ feedback for the MAC PDU containing the UE contention resolution identifier MAC CE, contention resolution is considered successful for the SI request as described in Clause 5.1.5:

[0255] 4> Stop the timeAlignmentTimer associated with this TAG.

[0256] 2> Otherwise:

[0257] 3> Ignore received timing advance commands.

[0258] 1> When an absolute timing advance command is received in response to an MSGA transmission containing C-RNTI MAC CE as specified in Clause 5.1.4a:

[0259] 2> Timing advance commands are applied to PTAG applications;

[0260] 2> Start or restart the timeAlignmentTimer associated with PTAG.

[0261] 1> When the timeAlignmentTimer expires:

[0262] 2> If timeAlignmentTimer is associated with PTAG, then:

[0263] 3. Refresh all HARQ buffers for all serving cells;

[0264] 3> Notify RRC to release PUCCHs used for all serving cells (if configured);

[0265] 3> Notify RRC to release SRS for all serving cells (if configured);

[0266] 3> Clear any configured downlink assignments and configured uplink permissions;

[0267] 3> Remove any PUSCH resources used for semi-static CSI reporting;

[0268] 3> It is assumed that all running timeAlignmentTimers have expired;

[0269] 3> Maintain N for all tags TA (defined in TS 38.211[8]).

[0270] 2> Otherwise, if timeAlignmentTimer is associated with STAG, then all serving cells belong to this TAG:

[0271] 3> Refresh all HARQ buffers;

[0272] 3> Notify RRC to release PUCCH (if configured);

[0273] 3> Notify RRC to release SRS (if configured);

[0274] 3> Clear any configured downlink assignments and configured uplink permissions;

[0275] 3> Remove any PUSCH resources used for semi-static CSI reporting;

[0276] 3> Maintaining N for this TAG TA (as defined in TS 38.211[8]).

[0277] When a MAC entity stops uplink transmission due to the maximum uplink transmission timing difference between TAGs of MAC entities or the fact that the maximum uplink transmission timing difference between TAGs of any MAC entity of the UE has been exceeded, the MAC entity considers the timeAlignmentTimer associated with the SCell to have expired.

[0278] When the timeAlignmentTimer associated with the TAG to which the serving cell belongs is not running, the MAC entity will not perform any uplink transmissions on the serving cell, except for the random access preamble and MSGA transmissions. Furthermore, when the timeAlignmentTimer associated with the PTAG is not running, the MAC entity will not perform any uplink transmissions on any serving cell, except for the random access preamble and MSGA transmissions on the SpCell.

[0279] 6.1.3.4 Timing Advancement Command MAC CE

[0280] The timing advance command MAC CE is identified by a MAC subheader with the LCID specified in Table 6.2.1-1.

[0281] It has a fixed size and consists of a single octet as defined below ( Figure 6 .1.3.4-1):

[0282] -TAG ID: This field indicates the TAG ID of the addressed TAG. TAGs containing SpCells have TAG ID 0. The field is 2 bits long.

[0283] - Timing Advancement Command: This field indicates the index value T of the amount of timing adjustments that must be applied to control MAC entities (as specified in TS 38.213[6]). A (0, 1, 2, ..., 63). The field length is 6 characters.

[0284] Figure 5 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.4-1: Timing advance command MAC CE.

[0285] 6.1.3.4a Absolute Timing Advance Command (MAC CE)

[0286] The absolute timing advance command (MAC CE) is identified by a MAC subheader with the eLCID specified in Table 6.2.1-1b.

[0287] It has a fixed size and consists of two octets as defined below ( Figure 6 .1.3.4a-1)

[0288] - Timing Advancement Command: This field indicates the index value TA of the amount of timing adjustments that must be applied to the MAC entity in TS 38.213[6]. The field size is 12 bits;

[0289] Figure 6 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.4a-1: Absolute Timing Advance Command MACCE.

[0290] 6.1.3.15 TCI status indication for UE-specific PDCCH MAC CE

[0291] The TCI status indication of the UE-specific PDCCH MAC CE is identified by a MAC subheader having the LCID specified in Table 6.2.1-1. It has a fixed 16-bit size with the following fields:

[0292] -Serving Cell ID: This field indicates the identifier of the serving cell for which the MAC CE is applied. The field is 5 bits long. If the indicated serving cell is configured as part of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 as specified in TS 38.331[5], then this MAC CE is applied to all serving cells in a set of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 respectively;

[0293] -CORESET ID: This field indicates the control resource set identified by the ControlResourceSetId specified in TS 38.331[5], indicating its TCI status. When the field value is 0, it refers to the control resource set configured by controlResourceSetZero as specified in TS 38.331[5]. The field is 4 bits long;

[0294] -TCI State ID: This field indicates the TCI state applicable to the control resource set identified by the CORESET ID field, as specified in TS 38.331[5]. If the CORESET ID field is set to 0, this field indicates the TCI state for the first 64 TCI states configured via tci-States-ToAddModList and tci-States-ToReleaseList in the PDSCH-Config of the BWP in action. If the CORESET ID field is set to a value other than 0, this field indicates the TCI state configured via tci-StatesPDCCH-ToAddList and tci-StatesPDCCH-ToReleaseList in the controlResourceSet identified by the indicated CORESET ID. The field is 7 bits long.

[0295] Figure 7 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.15-1: TCI status indication for UE-specific PDCCH MACCE.

[0296] 6.1.3.14 TCI State Activation / Deactivation for UE-Specific PDSCH MAC CE

[0297] The TCI status activation / deactivation of the UE-specific PDSCH MAC CE is identified by a MAC subheader with the LCID specified in Table 6.2.1-1. It has a variable size consisting of the following fields:

[0298] -Serving Cell ID: This field indicates the identifier of the serving cell for the MAC CE application. The field is 5 bits long. If the indicated serving cell is configured as part of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 as specified in TS 38.331[5], then this MAC CE applies to all serving cells configured in a set of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 respectively;

[0299] -BWP ID: This field indicates the code point of the DL BWP applied by the MAC CE as specified in the DCI bandwidth portion indicator field as defined in TS 38.212[9]. The BWP ID field is 2 bits long. If this MAC CE is applied to a set of serving cells, then this field is ignored;

[0300] -T i If a TCI state with TCI-StateId i exists as specified in TS 38.331[5], this field indicates the active / deactivated state of the TCI state with TCI-StateId i; otherwise, the MAC entity will ignore T. i Field. T i The field is set to 1 to indicate that a TCI state with TCI-StateId i will be activated and mapped to the code point of the DCI transport configuration indication field, as specified in TS 38.214[7]. i The field is set to 0 to indicate that the TCI state with TCI-StateId i will be deactivated and not mapped to the code point in the DCI transport configuration indication field. The code point mapped to the TCI state is determined by its value in the TCI transport configuration indication field. i The ordinal position of all TCI states with the field set to 1 is determined, that is, T i The first TCI state with the field set to 1 will map to the code point value 0, T i A second TCI state with a field set to 1 will map to a code point value of 1, and so on. The maximum number of active TCI states is 8;

[0301] -CORESET Pool ID: This field indicates that the mapping between the active TCI state and the code point indicated by the DCI transport configuration set in field Ti is specific to the ControlResourceSetId configured with the CORESET Pool ID as specified in TS 38.331[5]. This field set to 1 indicates that this MAC CE will be applied to DL transports scheduled via CORESET with a CORESET Pool ID equal to 1; otherwise, this MAC CE will be applied to DL transports scheduled via a CORESET Pool ID equal to 0. If coresetPoolIndex is not configured for any CORESET, the MAC entity will ignore the CORESET Pool ID field in this MAC CE when it is received. If the serving cell in the MAC CE is configured in a cell list containing more than one serving cell, the CORESET Pool ID field will be ignored when the MAC CE is received.

[0302] Figure 8For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.14-1: TCI state activation / deactivation for UE-specific PDSCH MACCE.

[0303] 6.1.3.24 Enhanced TCI State Activation / Deactivation for UE-Specific PDSCH MAC CE

[0304] UE-specific PDSCH MAC CE enhanced TCI state activation / deactivation is identified by a MAC PDU subheader with the eLCID as specified in Table 6.2.1-1b. It has a variable size consisting of the following fields:

[0305] -Serving Cell ID: This field indicates the identifier of the serving cell for the MAC CE application. The field is 5 bits long. If the indicated serving cell is configured as part of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 as specified in TS 38.331[5], then this MAC CE applies to all serving cells configured in a set of simultaneousTCI-UpdateList1 or simultaneousTCI-UpdateList2 respectively;

[0306] -BWP ID: This field indicates the code point of the DL BWP for the MAC CE application as specified in TS 38.212[9] as the DCI bandwidth portion indicator field. The BWP ID field is 2 bits long;

[0307] -C i This field indicates whether a TCI status ID exists. i,2 An eight-bit byte. If this field is set to "1", then there exists a TCI status ID. i,2 The eight-bit byte. If this field is set to "0", then there is no TCI status ID. i,2 Eight bytes;

[0308] -TCI Status ID i,j This field indicates the TCI state identified by TCI-StateId as specified in TS 38.331[5], where i is the index of the code point of the DCI transport configuration indicator field as specified in TS 38.212[9], and TCI state ID. i,j This indicates the j-th TCI state indicated by the i-th code point in the DCI transport configuration indication field. The TCI code point mapped to the TCI state consists of multiple sets of TCI state IDs.i,j The ordinal position of the field among all TCI code points is determined, i.e., it has a TCI state ID. 0,1 and TCI status ID 0,2 The first TCI code point will be mapped to code point value 0, which has a TCI state ID. 1,1 and TCI status ID 1,2 The second TCI code point will be mapped to code point value 1, and so on. TCI State ID i,2 Based on C i The field indication is optional. The maximum number of active TCI code points is 8, and the maximum number of TCI states mapped to TCI code points is 2.

[0309] Figure 9 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.24-1: Enhanced TCI state activation / deactivation for UE-specific PDSCH MACCE.

[0310] 6.1.3.25 Enhanced PUCCH Spatial Relationship Activation / Deactivation MAC CE

[0311] Enhanced PUCCH spatial relation activation / deactivation is identified by a MAC subheader with an eLCID as specified in Table 6.2.1-1b. It has a variable size with the following fields:

[0312] - Serving Cell ID: This field indicates the identifier of the serving cell for the MAC CE application. The field is 5 bits long.

[0313] -BWP ID: This field indicates the UL BWP of the MAC CE application as the code point of the DCI bandwidth portion indicator field as specified in TS 38.212[9]. The BWP ID field is 2 bits long;

[0314] -PUCCH Resource ID: This field contains an identifier for a PUCCH resource ID as specified in TS 38.331[5], which will be activated by the spatial relationship indicated by the spatial relationship information ID field in the following eight bytes. The field is 7 bits long. If the indicated PUCCH resource ID is contained in the PUCCH resource group of the indicated ULBWP (via the resourceGroupToAddModList configuration specified in TS 38.331[5]), then other PUCCH resources in the same PUCCH resource group are not indicated in the MAC CE, and this MAC CE applies to all PUCCH resources in the PUCCH resource group;

[0315] - Spatial Relation Information ID: This field contains PUCCH-SpatialRelationInfoId-1, where PUCCH-SpatialRelationInfoId is the identifier of the PUCCH spatial relationship information in PUCCH-Config, and the PUCCH resource ID is configured as specified in TS 38.331[5]. The field length is 6 bits;

[0316] Figure 10 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.25-1: Enhanced PUCCH spatial relation activation / deactivation MAC CE.

[0317] 6.1.3.26 Enhanced SP / AP SRS Spatial Relationship Indicator MAC CE

[0318] The Enhanced SP / AP SRS Spatial Relationship Indicator MAC CE is identified by a MAC subheader with an eLCID as specified in Table 6.2.1-1b. It has a variable size with the following fields:

[0319] -A / D: This field indicates whether the indicated SP SRS resource set is activated or deactivated. A value of 1 indicates activation; otherwise, it indicates deactivation. If the indicated SRS resource set ID is used for an AP SRS resource set, the MAC entity will ignore this field.

[0320] - SRS Resource Set Cell ID: This field indicates the identifier of the serving cell, which contains the indicated SP / AP SRS resource set. If the C field is set to 0, this field also indicates the identifier of the serving cell, which contains the resource ID. i This field indicates all resources. The field length is 5 characters.

[0321] - BWP ID of SRS resource set: This field indicates the UL BWP containing the indicated SP / AP SRS resource set, which is the code point of the DCI bandwidth portion indicator field as specified in TS 38.212[9]. If the C field is set to 0, this field also indicates the identifier of the BWP containing the resource ID. i This field indicates all resources. The field length is 2 characters.

[0322] -C: This field indicates whether an octet containing the Resource Serving Cell ID and Resource BWP ID fields exists. If this field is set to 1, then the Resource Serving Cell ID and Resource BWP ID fields exist; otherwise, they do not exist, causing the MAC entity to ignore the Resource Serving Cell ID and Resource BWP ID fields.

[0323] -SUL: This field indicates whether MAC CE is applied to a NUL carrier or a SUL carrier configuration. This field is set to 1 to indicate that it is applied to a SUL carrier configuration, and is set to 0 to indicate that it is applied to a NUL carrier configuration;

[0324] -SRS Resource Set ID: This field indicates the SP / APSRS resource set ID identified by the SRS-ResourceSetId specified in TS 38.331[5]. The field is 4 bits long;

[0325] -F i This field indicates the type of resource used for spatial relationships of SRS resources within an SP / AP SRS resource set, indicated by the SP / AP SRS Resource Set ID field. F0 refers to the first SRS resource within the resource set, F1 to the second SRS resource, and so on. The field is set to 1 to indicate the use of an NZP CSI-RS resource index, and set to 0 to indicate the use of an SSB index or an SRS resource index. The field is 1 bit long. This field exists only when MAC CE is active for SP SRS resource sets (i.e., the A / D field is set to 1) or for AP SRS resource sets.

[0326] -Resource Service Community ID i This field indicates the identifier of the serving cell, on which the resource derived from the spatial relationship of SRS resource i resides. The field is 5 bits long.

[0327] -Resource BWP ID i This field indicates the code point of the UL BWP as a DCI bandwidth portion indicator field as specified in TS 38.212[9], where the resource derived from the spatial relationship of SRS resource i is located at the code point. The field is 2 bits long;

[0328] -Resource ID i This field contains the identifier of the resource derived from the spatial relationship of SRS resource i. Resource ID0 refers to the first SRS resource within the resource set, resource ID1 refers to the second SRS resource, and so on. If F i If set to 0, then the first digit of this field will always be set to 0. If F iIf F is set to 0 and the second bit of this field is set to 1, then the remainder of this field contains the SSB-Index as specified in TS 38.331[5]. If F i If the second bit of this field is set to 0, then the remainder of this field contains the SRS-ResourceId as specified in TS 38.331[5]. The field is 8 bits long. This field exists only when MAC CE is used for activation of SP SRS resource sets, i.e., when the A / D field is set to 1, or when used for AP SRS resource sets;

[0329] Figure 11 For 3GPP TS 38.321, V16.5.0 Figure 6 Reproduction of .1.3.26-1: Enhanced SP / AP SRS Spatial Relationship Indicator MAC CE.

[0330] In 38.331[4], cell configuration and SRS configuration are introduced:

[0331] CellGroupConfig

[0332] The CellGroupConfig IE is used to configure a master cell group (MCG) or a secondary cell group (SCG). A cell group consists of a MAC entity, a set of logical channels with associated RLC entities, a primary cell (SpCell), and one or more secondary cells (SCells).

[0333] CellGroupConfig information element

[0334]

[0335]

[0336] The IE MAC-CellGroupConfig is used to configure the MAC parameters of a cell group, including DRX.

[0337] MAC-CellGroupConfig information element

[0338]

[0339] The IE ControlResourceSet is used to configure the time / frequency control resource set (CORESET) in which downlink control information is searched (see TS 38.213

[13] Clause 10.1).

[0340] ControlResourceSet information element

[0341]

[0342]

[0343]

[0344] ServingCellConfigCommon

[0345] The ServingCellConfigCommon (IE) is used to configure cell-specific parameters for the UE's serving cell. The IE contains parameters that the UE will typically obtain from the SSB, MIB, or SIB when accessing a cell from IDLE. Through this IE, the network provides this information in dedicated signaling when configuring an SCell or Additional Cell Group (SCG) for the UE. The network also provides support for SpCells (MCGs and SCGs) after synchronous reconfiguration.

[0346] ServingCellConfigCommon information element

[0347]

[0348]

[0349]

[0350]

[0351] TAG-Config

[0352] IE TAG-Config is used to configure parameters for time alignment groups.

[0353] TAG-Config information element

[0354]

[0355]

[0356] -SRS-Config

[0357] The IE SRS-Config is used to configure the transmission of probe reference signals. This configuration defines lists of SRS-Resources, SRS-PosResources, SRS-PosResourceSets, and SRS-ResourceSets. Each resource set defines either an SRS-Resource or an SRS-PosResources set. The network uses the configured aperiodicSRS-ResourceTrigger (L1DCI) to trigger the transmission of either an SRS-Resource or an SRS-PosResources set.

[0358] SRS-Config information element

[0359]

[0360]

[0361]

[0362]

[0363]

[0364]

[0365]

[0366]

[0367]

[0368]

[0369]

[0370]

[0371]

[0372]

[0373]

[0374]

[0375] In 3GPP specification 38.211[5], a frame structure is introduced:

[0376] N TATiming advance between downlink and uplink; see Clause 4.3.1

[0377] N TA,offset The fixed offset used to calculate timing advance; see Clause 4.3.1

[0378] …

[0379] 4.3 Frame Structure

[0380] 4.3.1 Frames and Subframes

[0381] Downlink, uplink, and sidelink transmissions are organized into a T f =(Δf max N f / 100)·T c = A frame with a duration of 10ms, each frame consisting of T sf =(Δf max N f / 1000)·T c It consists of ten subframes with a duration of 1 ms. The number of consecutive OFDM symbols in each subframe is... Each frame is divided into two equal half-frames consisting of five subframes, each having half-frame 0 composed of subframes 0-4 and half-frame 1 composed of subframes 5-9.

[0382] On a carrier, there is one set of frames in the uplink and one set of frames in the downlink.

[0383] The number of uplink frames to be transmitted from the UE will begin before the corresponding downlink frame at the UE. TA =(N TA +N TA，offset )T c , where N TA,offset As given in [5, TS 38.213], except for the msgA transmission on the PUSCH used therein.

[0384] Figure 12 For 3GPP TS 38.211, V16.6.0 Figure 4 Reproduction of .3.1-1: Uplink-Downlink Timing Relationship.

[0385] In [6], DCI format 1_0 is listed below:

[0386] 7.3.1.2.1 Format 1_0

[0387] DCI format 1_0 is used for scheduling PDSCH in a DL cell.

[0388] The following information is transmitted using DCI format 1_0 with a CRC scrambled by C-RNTI, CS-RNTI, or MCS-C-RNTI:

[0389] -Identifier for DCI format- 1 bit

[0390] - This field is always set to 1, indicating DL DCI format.

[0391] -Frequency Domain Resource Allocation- Ones place, of which As given by Clause 7.3.1.0

[0392] If the CRC of DCI format 1_0 is scrambled by C-RNTI and all fields in the "Frequency Domain Resource Allocation" field are 1, then DCI format 1_0 is used for random access procedures initiated by PDCCH commands, where all other fields are set as follows:

[0393] - Random access preamble index - 6 bits, ra-PreambleIndex according to Clause 5.1.2 of [8, TS38.321].

[0394] -UL / SUL Indicator -1 bit. If the value of "Random Access Preamble Index" is not all zeros, and if the UE is configured to use the supplementaryUplink in the ServingCellConfig of the cell, then this field indicates which UL carrier in the cell transmits PRACH according to Table 7.3.1.1.1-1; otherwise, this field is reserved.

[0395] -SS / PBCH Index - 6 bits. If the value of "Random Access Preamble Index" is not all zeros, then this field indicates the SS / PBCH that will be used to determine the RACH timing for PRACH transmission; otherwise, this field is reserved.

[0396] -PRACH Mask Index - 4 bits. If the value of "Random Access Preamble Index" is not all zeros, then this field indicates the RACH timing associated with the SS / PBCH indicated by "SS / PBCH Index" for PRACH transmission, according to Clause 5.1.1 of [8, TS38.321]; otherwise, this field is reserved.

[0397] - Reserved bits - 12 bits, used for operation in cells with shared spectrum channel access; otherwise, 10 bits.

[0398] In the new radio (NR) enhancements to the multiple-input / multiple-output (eMIMO) work item, multiple transceiver point (TRP) (or mTRP) operation is introduced. User equipment (UE) can perform communication with a cell of the network (e.g., gNB) via more than one TRP of the cell. In Rel-16, multiple physical downlink shared channel (PDSCH) transmissions are introduced. Two (activated) transmission configuration indicator (TCI) states can be used to indicate to the UE to receive (two) PDSCH transmission opportunities. Each TCI state can be associated with a PDSCH transmission. PDSCH transmissions can have non-overlapping frequency and / or time domain resource allocations regarding other PDSCH transmission opportunities. In the NR version 17 work item for MIMO enhancements ([1] RP-193133 New WID: Further Enhancements to MIMO for NR), multiple TRP transmissions for the physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), and physical downlink control channel (PDCCH) are introduced. The goal of multiple TRP PUSCHs is to enable the UE to transmit the same data to the network via multiple PUSCHs to achieve reliability (e.g., using spatial diversity, beamforming, or spatial relational information with multiple TCI states). Re-17 introduced inter-cell multiple TRP (or mTRP) operations. That is, the UE can communicate via a first TRP from the serving cell and a second TRP from a non-serving cell (e.g., a cell with a different Physical Cell Identity (PCI) than the serving cell). The Re-18 RAN workshop introduced (synchronous) uplink (UL) transmission via multiple panels. For example, the UE can perform UL transmission on the serving cell using its first panel and on a non-serving cell using its second panel. In versions prior to Re-17, mechanisms for TRP synchronization in multiple TRP operations (within the same cell or across different cells) were designed. When performing an mTRP operation, the UE can have the same UL time alignment (TA) within the TRPs. In other words, the UE can perform UL transmission on the TRP within an mTRP operation by applying a single TA. Rel-18 discusses a more realistic scenario. From the UE's perspective, different TRPs can be in different locations (e.g., not in the same place) and can be asynchronous (i.e., TRPs can be asynchronous). In this invention, mechanisms for obtaining and / or maintaining TAs for asynchronous TRPs (associated with the same cell or different cells) during multi-TRP operations are described.

[0399] Inter-cell mTRP-Random Access Channel (RACH) obtains TA

[0400] One concept of this invention is that for a UE performing a multi-TRP (mTRP) operation on a first TRP and a second TRP, the UE can obtain first TA information associated with the first TRP and second TA information associated with the second TRP. For a UE configured with UL resources on a non-serving cell, the UE can initiate a random access procedure on the non-serving cell (its TRP). The UE can initiate a random access procedure to obtain TA information associated with the non-serving cell (its TRP). The UE can perform a multi-TRP (mTRP) operation associated with a TRP on the non-serving cell (and another TRP on the serving cell). After the random access procedure is completed, the UE may not consider the non-serving cell as the serving cell (e.g., not as a secondary or primary cell).

[0401] For example, a UE can perform an mTRP operation on a first TRP on a non-serving cell and a second TRP on a serving cell. The UE can obtain TA information associated with the serving cell (the second TRP) via a prior random access procedure. The UE can also obtain TA information associated with a non-serving cell without a prior random access procedure. The first TRP and the second TRP are not synchronized (e.g., the UE has different N values ​​for the first TRP and the second TRP). TA and / or N TA,offset ).

[0402] In response to signaling from the network, the UE may initiate a (later) random access procedure on a first TRP (associated with a non-serving cell). The signaling may be PDCCH signaling (e.g., a PDCCH command-type signal). The signaling may indicate a non-serving cell (e.g., indicating the physical cell identifier of the non-serving cell). The signaling may indicate the first TRP (e.g., indicating the TCI status and / or control resource set pool index and / or probe reference signal (SRS) resource set or spatial relation information or beam fault detection reference signal (BFD-RS) set associated with the first TRP). Additionally and / or alternatively, the control resource set pool index may be implicitly indicated by which resource (e.g., control resource set (CORESET)) the UE receives the PDCCH command (or PDCCH signaling) on.

[0403] (The latter) random access procedure can be a contention-free and / or contention-based random access procedure. The UE can obtain TA information associated with the non-serving cell (the first TRP) from the (the latter) random access procedure.

[0404] The UE can apply TA information associated with a non-serving cell (first TRP) to UL transmission on the first TRP of the non-serving cell. The UE can apply TA information associated with a serving cell (second TRP) to UL transmission on the second TRP of the serving cell.

[0405] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on the non-serving cell (TRP) based at least on the TA information provided / configured when configuring and / or activating the non-serving cell. If TA information for the non-serving cell (TRP) is provided or configured, the UE may not initiate a random access procedure on the non-serving cell.

[0406] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on a non-serving cell (TRP) based at least on whether resources and / or configuration for a random access procedure on a non-serving cell are provided (by the network). If resources and / or configuration for a random access procedure on a non-serving cell are not provided, then the UE may not initiate a random access procedure on the non-serving cell (TRP).

[0407] In response to the activation of TCI status or spatial relationship information associated with a non-serving cell, the UE may initiate a random access procedure on the non-serving cell. Alternatively, the UE may initiate a random access procedure on the non-serving cell in response to the activation of TRP associated with the non-serving cell. Alternatively, the UE may initiate a random access procedure on the non-serving cell in response to a PDCCH command (or PDCCH signaling) provided by the network.

[0408] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on a non-serving cell in response to activation of TRP or TCI status or spatial relationship information associated with the non-serving cell, at least based on whether TA information (associated with the non-serving cell or TRP) is provided when configuring the non-serving cell or when configuring the UL resources of the non-serving cell. If TA information associated with the non-serving cell or TA information associated with the TRP is provided when configuring the non-serving cell, then the UE may not initiate a random access procedure on the non-serving cell.

[0409] Additionally and / or alternatively, the UE may determine, based on the content or attributes of activation signaling, whether to initiate a random access procedure on the non-serving cell in response to activation signaling for TRP or TCI status or spatial relationship information associated with the non-serving cell. If or when the activation signaling instructs the UE to perform a random access procedure (to obtain TA information of the non-serving cell), then the UE may determine to initiate a random access procedure on the non-serving cell in response to the activation signaling. If or when the activation signaling does not instruct the UE to perform a random access procedure, then the UE may determine not to initiate a random access procedure on the non-serving cell in response to the activation signaling. The UE may apply the TA information of the serving cell to UL transmission on the non-serving cell (after activating the non-serving cell). The activation signaling may be PDCCH signaling. The activation signaling may instruct the UE to apply the (existing) TA information of the serving cell on the non-serving cell.

[0410] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on the non-serving cell in response to the activation of TRP or TCI state or spatial relation information associated with the non-serving cell, based at least on the existence of valid TA information for the non-serving cell or TRP. If valid TA information for the non-serving cell exists when the TRP of the non-serving cell is activated, the UE may not initiate a random access procedure on the non-serving cell. The UE may apply the valid TA information of the non-serving cell to UL transmission on the non-serving cell (after the non-serving cell is activated). For example, the UE may consider the TA information valid when a timer (e.g., timeAlignmentTimer) associated with the TA information is running.

[0411] Additionally and / or alternatively, the UE may stop the timer when the TRP of a non-serving cell is deactivated. The UE may consider the TA information invalid when the timer associated with the TA information (e.g., timeAlignmentTimer) is not running.

[0412] mTRP UE-RACH obtains TA within the cell

[0413] Another concept of the present invention is that for a UE performing mTRP operation on a first TRP on a cell and a second TRP on the same cell, the UE may initiate a first random access procedure for the first TRP on the cell to obtain the first TA information of the first TRP, and initiate a second random access procedure for the second TRP on the cell to obtain the second TA information of the second TRP.

[0414] For example, for a UE configured with UL resources of a serving cell, the UE is configured with a first TRP of the serving cell for UL transmission. The UE initiates a first random access procedure on the first TRP of the serving cell to obtain the first TA information of the first TRP (e.g., initiated by a PDCCH command provided by the network or in response to a connection establishment initiation). The UE performs UL and / or downlink (DL) communication with the first TRP by applying the first TA information of the first TRP. The UE is configured with a second TRP of the serving cell. The network may instruct the UE to perform (intra-cell) mTRP operations (e.g., DL or UL transmission) on the first TRP and the second TRP. The network may instruct the UE to perform mTRP operations via activation signaling, such as indicating that the activated TCI state (or spatial relation information) associated with the second TRP activates the Media Access Control (MAC) CE (or spatial relation information activates the MAC CE). The first TRP and the second TRP are not synchronized. In response to TCI state activation MAC CE (or spatial relationship information activation MAC CE), the UE initiates a second random access procedure on the second TRP to obtain the second TA information of the second TRP. Upon completion of the second random access procedure, the UE can perform UL and / or DL ​​communication with the second TRP by applying the second TA information (and perform UL and / or DL ​​communication with the first TRP by applying the first TA information). Alternatively and / or alternatively, the UE may initiate a second random access procedure without responding to a PDCCH command. The UE initiates a second random access procedure in response to the activation of the second TRP or the activation of multi-TRP operation. Alternatively and / or alternatively, the UE initiates a second random access procedure in response to receiving PDCCH signaling, wherein the PDCCH signaling instructs the UE to perform UL transmission or activate mTRP operation on the second TRP.

[0415] The UE may determine, in response to receiving PDCCH signaling, whether to obtain and / or maintain the cell's second TA information (other than the first TA information) via a random access procedure, based at least on the format or fields of the PDCCH signaling. If the PDCCH signaling is a PDCCH command (e.g., Downlink Control Information (DCI) format 1_0), then the UE may not obtain the second TA information. If the PDCCH signaling is not a PDCCH command (e.g., the PDCCH signaling indicates a random access procedure for the second TRP in a field), then the UE may initiate a random access procedure and obtain the second TA information. Preferably, the field may be a single bit used to identify whether to update the current TA or obtain the second TA. Preferably, the field may reuse one of the currently reserved bits of DCI format 1_0. Additionally and / or alternatively, the UE may determine, at least based on the resources (e.g., CORESET) on which the UE receives the PDCCH signaling, whether to obtain the second TA information in response to the PDCCH signaling. If or when a PDCCH signaling is received on a CORESET associated with the second TRP, the UE may initiate a random access procedure on the second TRP in response to the PDCCH signaling (and obtain the second TA information of the second TRP). If or when a PDCCH signaling is received on a CORESET associated with the first TRP, the UE may initiate a random access procedure on the second TRP without responding to the PDCCH signaling. If or when a PDCCH signaling is received on a CORESET associated with the first TRP, the UE may update or regenerate the first TA information of the first TRP.

[0416] Additionally and / or alternatively, the UE may determine, based on the content or attributes of activation signaling, whether to initiate a random access procedure on the second TRP in response to activation signaling associated with the second TRP (e.g., TCI status or spatial relationship information activating MAC CE). If or when the activation signaling instructs the UE to perform a random access procedure (to obtain TA information of the second TRP), the UE may determine to initiate a random access procedure on the second TRP in response to the activation signaling. If or when the activation signaling does not instruct the UE to perform a random access procedure, the UE may determine not to initiate a random access procedure on the second TRP in response to the activation signaling. The UE may apply the (first) TA information of the first TRP for UL transmission on the second TRP (after activating the second TRP).

[0417] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on the second TRP in response to activation of the TCI state (or spatial relationship information) associated with the second TRP, at least based on the existence of valid TA information for the second TRP. If valid TA information exists for the second TRP at the time of activation, the UE may not initiate a random access procedure on the second TRP. The UE may apply the valid TA information of the second TRP to UL transmissions on the second TRP (after activation of the second TRP). For example, the UE may consider the TA information valid when a timer (e.g., timeAlignmentTimer) associated with the TA information is running. The network may indicate the valid TA information of the second TRP to the UE (via a Radio Resource Control (RRC) message or activation signaling of the TRP). The valid TA information may be associated with or the same as the TA information of the first TRP.

[0418] Additionally and / or alternatively, the UE may stop the timer when the second TRP of the serving cell is deactivated. The UE may consider the TA information invalid when the timer associated with the TA information (e.g., timeAlignmentTimer) is not running.

[0419] The first TRP and the second TRP are out of sync. The UE can maintain different groups of N for the first TRP and the second TRP. TA and / or N TA,offset .

[0420] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on the second TRP on the cell, at least based on the TA information provided / configured when configuring and / or activating the second TRP. If the TA information for the second TRP is provided or configured, the UE may not initiate a random access procedure on the second TRP.

[0421] Additionally and / or alternatively, the UE may determine whether to initiate a random access procedure on the second TRP in response to activation of the second TRP in the cell, at least based on whether resources and / or configuration for a random access procedure on the second TRP are provided (by the network). If resources and / or configuration for a random access procedure on the second TRP are not provided, then the UE may not initiate a random access procedure on the second TRP. Resources and / or configuration for the random access procedure may be configured / provided per TRP (e.g., more than one set of resources in a cell for different TRP / TCI state / spatial relationship information).

[0422] Additionally and / or alternatively, the network may provide an SRS configuration (e.g., SRS-config) for an SRS resource(set) associated with a second TRP for the cell used by the UE. The SRS resource(set) may indicate the periodicity and / or time slot offset of the SRS resources. The UE may transmit SRS to the second TRP based on the SRS configuration. In response to receiving the SRS configuration, the UE may (begin) transmitting SRS via the SRS resources (e.g., periodic SRS transmission). Alternatively, in response to receiving an activation signaling for the SRS configuration, the UE may (begin) transmitting SRS via the SRS resources (e.g., semi-static SRS transmission).

[0423] The UE can transmit the TA information of the first TRP of the cell (e.g., timing advance N). TA and / or offset N TA,offset The TA is applied to SRS transmitted via SRS resources of the second TRP. Alternatively, the UE may not apply the TA (or apply zero TA) to SRS transmitted via SRS resources of the second TRP. Alternatively, the UE may apply previously configured TA information of the second TRP (e.g., via an RRC reconfiguration message) to SRS transmitted via SRS resources. SRS may be transmitted before the random access procedure is initiated or completed.

[0424] The UE can transmit SRS via the UL beam associated with the second TRP (via the SRS resources of the second TRP).

[0425] In response to the activation of the second TRP or as instructed by the network, the UE may initiate a random access procedure with the network and obtain the second TA information of the second TRP. The UE may apply or use the second TA information of the second TRP to transmit SRS via the SRS resources of the second TRP after the random access procedure is completed or the second TRP is activated, or in response to the completion of the random access procedure or the activation of the second TRP. The UE may apply or use the TA information of the first TRP to transmit SRS via the SRS resources of the first TRP (before and after the random access procedure on the second TRP). The UE may transmit SRS via the UL beam associated with the first TRP (via the SRS resources of the first TRP).

[0426] Provide NW TA

[0427] Another concept of the present invention is that for a UE performing multi-TRP (mTRP) operations on a first TRP and a second TRP, the network can provide or configure first TA information associated with the first TRP and second time alignment information associated with the second TRP. The network can provide per-TRP TA information to the UE.

[0428] The first TRP may be associated with a first cell (e.g., the serving cell of the UE), and the second TRP may be associated with a second cell (e.g., a non-serving cell of the UE). The first TRP may be a TRP of the first cell. The second TRP may be a TRP of the second cell.

[0429] Alternatively, the first TRP and the second TRP may be associated with the same cell (e.g., the UE's serving cell or the UE's non-serving cell). For the UE, a cell may be associated with two or more different TA information, which are associated with different TRPs of the cell.

[0430] In one instance, for a UE performing UL transmission or configured with UL resources on a TRP of a non-serving cell, the network can provide or (pre-)configure first TA information associated with the non-serving cell. Additionally and / or alternatively, the first TA information can be associated with the TRP of the non-serving cell (and not with other TRPs of the non-serving cell). The network can provide the first TA information via RRC configuration (e.g., an RRCReconfiguration message). The network can also configure the first TA information of the non-serving cell when configuring the non-serving cell to the UE, or in addition to configuring the non-serving cell to the UE. The UE may not apply the first TA information in response to receiving the configuration. The UE may not apply the first TA information until the TRP is activated for the UE (to perform UL transmission) and / or the non-serving cell is used for mTRP operation.

[0431] The first TA information may be associated with the TA (or timing advance group (TAG)) of the serving cell. For example, the first TA information may indicate that the TA of the non-serving cell (of the TRP) has the same value as the TA of the serving cell. Alternatively, the first TA information may indicate the offset of the TA of the non-serving cell (of the TRP) relative to the TA of the serving cell. The offset may be non-zero (or zero). The first TA information may indicate the identifier of the serving cell.

[0432] Alternatively, the first TA information may indicate that the TA of the non-serving cell (TRP) is zero.

[0433] In another instance, for a UE that performs UL transmission or has UL resources configured on a TRP of the serving cell, the network can provide or (pre-)configure first TA information associated with a first TRP of the serving cell and second TA information associated with a second TRP of the serving cell.

[0434] The second TA information can be associated with the first TA information (or TAG) of the serving cell. For example, the first TA information can indicate that the TA of the first TRP of the serving cell has the same value as the TA of the second TRP. Alternatively, the second TA information can indicate the offset of the second TA of the second TRP relative to the TA value of the first TRP. The offset can be non-zero (or zero). The first TA information can indicate the second TRP (for reference to the TA value).

[0435] Alternatively, the first TA information may indicate that the TA of the serving cell (TRP) is zero.

[0436] Additionally and / or alternatively, for UEs configured to perform mTRP operations on one or more cells (e.g., mTRP operations performed on a single serving cell and / or mTRP operations performed on both serving and non-serving cells), the network may provide or configure TA information associated with the TRP of one or more cells in response to or after the activation of the TRP.

[0437] For example, the network may transmit signaling to the UE to activate the TRP for at least UL transmission (e.g., activation signaling). The signaling may contain TCI state activation (e.g., MAC CE). The signaling may contain spatial relationship information indication or activation (e.g., MAC CE). The network may indicate TA information associated with the TCI state in the signaling. Additionally and / or alternatively, the network may indicate TA information associated with the TCI state or spatial relationship information via a second signaling signaling different from the signaling.

[0438] For example, the network may indicate TA information via DCI (or via PDCCH). Alternatively, the network may indicate TA information associated with TRP via MACCE (e.g., Timing Advancement Command MAC CE or Absolute Timing Advancement Command MAC CE).

[0439] NW determines the TA of the second TRP based on the received SRS and the TA of the first TRP.

[0440] In one instance, the network may determine the TA information for the second TRP for the UE based on the SRS transmitted by the UE to the second TRP. Alternatively and additionally, the network may determine the TA information for the second TRP for the UE based on the SRS transmitted by the UE to the second TRP and based on the first TA information associated with the first TRP. The network may obtain / determine the first TA information via a random access procedure initiated by the UE to the first TRP. The network may also obtain / determine the TA information for the second TRP for the UE without a random access procedure.

[0441] For example, the network may provide an SRS configuration (e.g., SRS-config) for an SRS resource(set) associated with a second TRP for the cell used by the UE. The SRS resource(set) may indicate the periodicity and / or time slot offset of the SRS resources. The UE may transmit SRS to the second TRP based on the SRS configuration. In response to receiving the SRS configuration, the UE may (begin) transmitting SRS via the SRS resources (e.g., periodic SRS transmission). Alternatively, in response to receiving an activation signaling for the SRS configuration, the UE may (begin) transmitting SRS via the SRS resources (semi-static SRS transmission).

[0442] The UE can use the TA information of the first TRP (e.g., timing advance N). TA and / or offset N TA,offset The TA is applied to SRS transmitted via SRS resources of the second TRP. Alternatively, the UE may not apply the TA (or apply zero TA) to SRS transmitted via SRS resources of the second TRP. Alternatively, the UE may apply previously configured TA information of the second TRP (e.g., via an RRC reconfiguration message) to SRS transmitted via SRS resources.

[0443] The UE can transmit SRS via the UL beam associated with the second TRP.

[0444] In response to receiving an SRS, the network can derive or determine the (relative) timing difference between the first TRP and the second TRP for the UE based on the timing of the received SRS. The network can derive the (absolute) timing advance associated with the second TRP for the UE, at least based on the SRS transmission. The network can determine the TA information (e.g., timing advance N) of the second TRP based on the received SRS. TA and / or offset N TA,offset And / or Timing Advancement Command (TA). After receiving the SRS, the network may provide / configure the TA information of the second TRP to the UE. For example, the network may provide a timing advance command to the UE to adjust the timing of the UL transmission of the second TRP. The UE may apply or use the second TA information of the second TRP to transmit the SRS via the SRS resources of the second TRP after receiving the TA information of the second TRP or in response to receiving the TA information of the second TRP (e.g., before activating the second TRP). The UE may apply or use the TA information of the first TRP to transmit the SRS via the SRS resources of the first TRP (both before and after receiving the TA information of the second TRP).

[0445] Alternatively, the UE may apply or use the TA information of the second TRP for transmitting (and / or transmitting via PUSCH / PUCCH) SRS after the second TRP is activated or after either the activation of the TCI state associated with the second TRP. The UE may apply or use the TA information of the first TRP for transmitting SRS via the SRS resources of the first TRP (before and after the activation of the second TRP and / or the TCI state associated with the second TRP). The UE may transmit SRS via the UL beam associated with the first TRP (via the SRS resources of the first TRP).

[0446] The second TRP can be associated with a non-serving cell (e.g., the UE can perform inter-cell mTRP operations on a first TRP associated with the serving cell and a second TRP associated with a non-serving cell). SRS configuration can be associated with a non-serving cell. The UE can begin transmitting SRS to the non-serving cell in response to receiving SRS configuration from the non-serving cell.

[0447] Alternatively, the second TRP may be associated with the serving cell. The second TRP and the first TRP may be associated with the same cell.

[0448] NW pre-configures a second TRP TA, and the UE transmits SRS after receiving the TA.

[0449] Alternatively, the network may not provide or derive the TA information for the second TRP based on SRS transmission from the UE to the second TRP. For example, the network may provide or pre-configure the TA information for the second TRP to the UE (e.g., via RRC reconfiguration or via cell configuration). After receiving the configuration, the UE may not apply the TA information for the second TRP. The UE may apply the TA information in response to the activation of the second TRP (e.g., activation of UL / DL panel or TCI status or spatial relationship information associated with the TRP). The UE may apply the TA information in response to the completion of a random access procedure associated with the second TRP or the first TRP.

[0450] The TA information of the second TRP may contain a relative value associated with the first TA information of the first TRP. For example, the TA information of the second TRP may contain a (time slot) offset relative to the first TA information of the first TRP. Setting the offset to 0 instructs the UE to apply the same TA information to the second TRP as to the first TRP (e.g., N). TA and / or N TA,offset Additionally and / or alternatively, the TA information of the second TRP may indicate (e.g., via cell index or bit value) whether the second TRP is synchronized with the first TRP. If the TA information of the second TRP indicates that the second TRP is synchronized with the first TRP, then the UE may apply the first TA information of the first TRP (e.g., applying N) to the second TRP. TA and / or NTA,offset ).

[0451] Additionally and / or alternatively, the TA information of the second TRP may contain (absolute) values ​​for timing advance or timing adjustment for the UE to perform UL transmissions to the second TRP (e.g., PUCCH, PUSCH, SRS). Setting the TA information to 0 instructs the UE to send N to the second TRP. TA and / or N TA,offset Set to 0. Alternatively and concurrently, the TA information of the second TRP may indicate or contain cell or TRP information (e.g., TCI status / control resource set pool index / SRS resource set / serving cell index / spatial relationship information). The UE can set the TA information of the second TRP by applying the same TA information of the indicated cell or TRP.

[0452] TA obtained through RACH

[0453] Additionally and / or alternatively, the network may not provide / configure the TA information of the second TRP, for example, via RRC configuration or via activation signaling of the second TRP. The UE may determine whether to initiate a random access procedure to obtain the TA information of the cell's second TRP, at least based on whether the TRP configuration and / or cell configuration indicates or contains the TA information of the second TRP.

[0454] If the TA information for the second TRP is not provided / configured by the network, the UE may initiate a random access procedure on the second TRP (to obtain the TA information). Alternatively, if a random access procedure (e.g., RACH resources) is provided or configured for the second TRP, the UE may initiate a random access procedure on the second TRP (to obtain the TA information). The UE may initiate a random access procedure when the second TRP is configured / activated. If the TA information for the second TRP is provided / configured by the network, for example via TRP configuration and / or cell configuration, then the UE may not initiate a random access procedure to obtain the TA information for the second TRP.

[0455] TRP-based TAG

[0456] Additionally and / or alternatively, for a UE performing mTRP operations on a first TRP and a second TRP, the UE may be configured with or equipped with a first TAG id associated with the first TRP and a second TAG id associated with the second TRP. The first TRP may be associated with the first TAG, and the second TRP may be associated with the second TAG. The UE may be configured with or maintain a first time alignment timer (TAT) for the first TAG and a second TAT for the second TAG. The first TRP may be associated with a first group of one or more TCI states or beams configured for the UE, and the second TRP may be associated with a second group of one or more TCI states or beams configured for the UE. For example, the UE may configure a first (group) of TCI states and a second (group) of TCI states via RRC configuration. The first (group) of TCI states may be associated with a serving cell indicated by the servingcellindex, and the second (group) of TCI states may be associated with a non-serving cell or the same serving cell indicated by the PCI. The first (group) TCI status can be associated with or configured with the first TAG id, and the second (group) TCI status can be associated with or configured with the second TAG id.

[0457] Additionally and / or alternatively, the first TRP may be associated with one or more spatial relationships (information) in a first group, and the second TRP may be associated with one or more spatial relationships (information) in a second group. For example, the UE may configure the first (group) of spatial relationships and the second (group) of spatial relationships via RRC configuration. The first (group) of spatial relationships may be associated with the serving cell indicated by the servingcellindex, and the second (group) of spatial relationships may be associated with a non-serving cell or the same serving cell indicated by the PCI. The first (group) of spatial relationships may be associated with or configured with a first TAG id, and the second (group) of spatial relationships may be associated with or configured with a second TAG id. For each TRP or for each TAG associated with different TRPs, the UE may maintain a timing advance (N) between the DL and UL. TA The network can provide different timing advance commands for each TRP (via the timing advance command MAC CE).

[0458] Based on cell-level TAG

[0459] Non-serving cells can be configured with TAGs (different from those of serving cells), or TAGs specifically for non-serving cells.

[0460] Additionally and / or alternatively, the UE may be configured by the network (e.g., gNB) with a TAG associated with a non-serving cell. The UE performs inter-cell mTRP operations via the DL and / or UL resources of the non-serving cell and via the DL and / or UL resources of the serving cell. The TAG associated with the non-serving cell may be different from the second TAG associated with the serving cell.

[0461] For example, consider a UE performing inter-cell mTRP operations on a serving cell and a non-serving cell. The UE may be configured with a first TAG associated with the serving cell (the serving cell in the cell group associated with the first TAG) and a second TAG associated with the non-serving cell (the non-serving cell in the cell group associated with the second TAG). The UE may maintain different time alignment timers (e.g., a first TAT) for the first TAG (associated with the serving cell) and the second TAG (associated with the non-serving cell). The UE may maintain different timing advances (e.g., a first N) for the first TAG (associated with the serving cell) and the second TAG (associated with the non-serving cell). TA Second N TA ).

[0462] In another example, the UE may be configured with a non-serving cell TAG (dedicated to) one or more non-serving cells. The UE may perform (inter-cell) mTRP operations on one or more non-serving cells (and one or more serving cells). The TAG may not be associated with a (activated) serving cell. When the time alignment timer associated with the non-serving cell TAG expires, the UE may refresh all Hybrid Automatic Repeat Request (HARQ) buffers for all non-serving cells and / or the UE may release the PUCCH and / or SRS for all non-serving cells and / or the UE may switch to a single TRP operation on the serving cell.

[0463] Each non-serving cell is an individual, not a group; or the first TRP within a cell belongs to the TAG, but the second TRP does not. Belongs to TAG

[0464] Additionally and / or alternatively, the UE may be configured or equipped with a TAG associated with the first TRP, and the second TRP may not be associated with a TAG or equipped with a TAG. The UE may have a time alignment timer for the second TRP. The UE may maintain (individual) timing advance (or N) TA Additionally and / or alternatively, the UE may have an offset (slot or symbol offset or microsecond or one or more time units, e.g., T) associated with the timing advance of the first TRP. C The UE can derive the TA of the second TRP based on the offset and TA of the first TRP.

[0465] In another instance, the UE's non-serving cell may not be associated with a TAG. Each of the non-serving cells can configure or maintain an individual time alignment timer. Each of the non-serving cells can maintain an individual N TA (or timing advance between downlink and uplink). Alternatively, the UE may have an offset (slot or symbol offset or microsecond or one or more time units, such as T) associated with the timing advance of the serving cell. C The UE can derive the TA of a non-serving cell based on the offset and TA of the serving cell.

[0466] Two TRPs belong to one TAG, maintaining two Ns. TA or N TA + offset; or belongs to a service small associated with a TAG. Districts and non-service cells, maintain two Ns TA or N TA +Offset

[0467] Additionally and / or alternatively, the first TRP and the second TRP may be associated with the same TAG. For both the first TRP and the second TRP, the UE may maintain the same time alignment timer. The UE may maintain (in the TAG) a first timing advance (between DL and UL) for the first TRP and a second timing advance for the second TRP. Additionally and / or alternatively, the UE may maintain, or the network may provide, a first TA for the first TRP and an offset for the second TRP in the TAG. The offset may be an offset based on the first TA. The UE may derive the TA of the non-serving cell based on the first TA and the offset (e.g., the TA of the second TRP is equal to the first TA plus the offset of the second TRP).

[0468] Additionally and / or alternatively, serving cells and non-serving cells may be associated with the same third tag.

[0469] Additionally and / or alternatively, the serving cell may be associated with the same TAG as the non-serving cell. The serving cell and non-serving cell may be associated with the same TAG. For both the serving cell and the non-serving cell, the UE may maintain the same time alignment timer. The UE may maintain a first timing advance for the serving cell (between DL and UL) and a second timing advance for the non-serving cell (in the TAG). Additionally and / or alternatively, the UE may maintain, or the network may provide, a first TA for the serving cell and an offset for the non-serving cell in the TAG. The offset may be an offset based on the first TA. The UE may derive the TA for the non-serving cell based on the first TA and the offset (e.g., the TA for the non-serving cell equals the first TA plus the offset for the non-serving cell).

[0470] For multi-TRP (mTRP) operations on the first TRP and the second TRP, the UE can maintain two TRPs, namely a first TAT and a second TAT. The first TAT can be associated with the first TRP. The second TAT can be associated with the second TRP. The first TRP and the second TRP can be associated with the same serving cell. Alternatively, the second TRP can be associated with a non-serving cell that is associated with the serving cell of the first TRP.

[0471] When or in response to the expiration of the first TAT, the UE may perform one or more of the following actions:

[0472] - Refresh all HARQ buffers used for serving cells.

[0473] -Release the PUCCH used to serve the cell.

[0474] - Release the SRS used to serve the cell.

[0475] - Clear any configured downlink allocations and configured uplink permissions for the serving cell.

[0476] - Clear any PUSCH resources used for semi-static channel state information (CSI) reporting for the serving cell.

[0477] - Maintain N for the first or third tag TA .

[0478] Additionally and / or alternatively, the UE may perform one or more of the following actions in response to the expiration of the first TAT (while the second TAT is still in operation and has not expired):

[0479] - (Do not) refresh all HARQ buffers used for non-serving cells.

[0480] - (Do not) release PUCCH used for non-serving cells.

[0481] - (Do not) release SRS for non-serving cells.

[0482] - (Do not) clear downlink allocations and uplink permissions configured for any non-serving cells.

[0483] - (Do not) clear any PUSCH resources used for semi-static CSI reporting of non-serving cells.

[0484] - (Do not) maintain the N of the second or third tag TA .

[0485] Additionally and / or alternatively, when or in response to the expiration of the first TAT, the UE may consider the second TAT to have expired.

[0486] When or in response to the expiration of the second TAT, the UE may perform one or more of the following actions:

[0487] - Refresh all HARQ buffers used for non-serving cells.

[0488] -Release the PUCCH used for non-serving cells.

[0489] -Release SRS for non-serving cells.

[0490] - Clear downlink allocations and uplink permissions configured for non-serving cells.

[0491] - Clear any PUSCH resources used for semi-static CSI reporting of non-serving cells.

[0492] - Maintain the second tag N TA .

[0493] Additionally and / or alternatively, the UE may perform one or more of the following actions in response to the expiration of the second TAT (while the first TAT is still in operation and has not expired):

[0494] - (Do not) refresh all HARQ buffers used for serving the cell.

[0495] - (Do not) release the PUCCH used to serve the cell.

[0496] - (Do not) release the SRS used to serve the cell.

[0497] - (Do not) clear any configured downlink allocations and configured uplink permissions for the serving cell.

[0498] - (Do not) clear any PUSCH resources used for semi-static CSI reporting of serving cells.

[0499] -(Not) maintain the first tag's N TA .

[0500] Additionally and / or alternatively, when or in response to the expiration of the second TAT, the UE may consider the first TAT to have expired.

[0501] For a UE performing inter-cell mTRP operations between a serving cell and a non-serving cell, when the time alignment timer associated with the non-serving cell expires (and the second time alignment timer associated with the serving cell has not expired), the UE can switch from mTRP operations on the serving cell to single TRP operations.

[0502] TAC MAC CE format

[0503] The network can provide time alignment (TA) information for different TRPs of the UE (e.g., the first TRP and the second TRP mentioned above). Each of the different TRPs can be associated with different timing advances between the DL and UL.

[0504] For example, a network (e.g., a gNB) may provide or transmit a MAC CE to the UE for the UE to apply timing advance commands. The MAC CE may contain one or more of the following fields:

[0505] - One or more TAG id fields, each indicating the id of the TAG.

[0506] - One or more non-serving cell ID fields, each indicating the identifier of the non-serving cell (e.g., PCI).

[0507] - One or more Timing Advance Command (TAC) fields, each indicating the relative or absolute timing advance of the TRP.

[0508] - One or more offset fields, each indicating a timing offset for the UE to derive the TA of the TRP (based on the TA of another TRP).

[0509] For example, the network (e.g., gNB) can provide or transmit a MAC CE to the UE for the UE to apply a TAC to a TRP associated with the serving cell and / or a non-serving cell (e.g., extended TAC MAC CE). An extended TAC MAC CE can provide TA commands for more than one TRP associated with the UE. In response to receiving a MAC CE, the UE can apply different TA commands to the corresponding TRP. Figure 13An example of an extended TAC MAC CE is shown. For a UE performing multiple TRP operations on different TRPs, namely TRP1 and TRP2 (e.g., via different TCI states or different spatial relationships associated with a TRP), the network transmits an extended TAC MAC CE to provide TA commands to the TRPs. The MAC CE contains or indicates two TAG IDs, TAG ID_1 and TAG ID_2. Each of the indicated TAG IDs is followed by TA commands for TAC_TRP1 and TAC_TRP2, respectively. TRP1 is associated with the TAG with TAG ID_1, and TRP2 is associated with the TAG with TAG ID_2. Additionally and / or alternatively, TRP1 is associated with a cell (e.g., a serving cell or a non-serving cell) where the cell is associated with TAG ID_1, and TRP2 is associated with a cell (e.g., the same cell as the cell associated with TRP1 or a different cell) where the cell is associated with TAG ID_2. In response to receiving a MAC CE, the UE applies the TA command TAC_TRP1 to TRP1 (and / or to the TAG with TAG ID_1) and applies the TA command TAC_TRP2 to TRP2 (and / or to the TAG with TAG ID_2).

[0510] TAC command for non-serving cells

[0511] Figure 14A The diagram illustrates another example of an extended TAC MAC CE (for non-serving cells). The MAC CE may optionally contain reserved bits (R). The MAC CE may contain a TAG ID. The TAG ID may be associated with at least one non-serving cell. The UE may perform UL transmission via at least one non-serving cell (e.g., based on inter-cell mTRP operation via the serving cell). Additionally and / or alternatively, the MAC CE may contain an identifier indicating the non-serving cell or an identifier associated with it (e.g., physical cell ID, PCI). The MAC CE may contain a TA command for the non-serving cell (TAC_non-serving cell). The TA command may be the absolute value (N) of the timing advance between the DL and UL of the non-serving cell. TA Alternatively, the TA command can be a relative value used to adjust the current timing advance between the DL and UL of a non-serving cell. Alternatively, the TA command can indicate an offset between the timing advance of at least one non-serving cell and the timing advance of the serving cell, wherein the UE performs inter-cell operations between at least one non-serving cell and the serving cell. The UE can apply the TA command to at least one non-serving cell indicated by a TAG ID or a non-serving cell ID. Figure 14BAnother example is shown, where the MAC CE indicates the offset (Offset_TRP2) of the second TRP. Offset_TRP2 is a timing offset relative to the timing advance TA1 of the first TRP. The UE can perform multiple TRP operations between the first TRP and the second TRP. The UE can derive the timing advance TA2 of the second TRP based on the offset 1 of the first TRP and the timing advance (e.g., TA2 = TA1 + Offset_TRP2). The MAC CE may contain second TRP information (e.g., the PCI or serving cell index or TAG ID associated with the second TRP).

[0512] Provide one TAG and two TACs for both serving and non-serving cells / one TAC + one offset

[0513] Figure 15A The diagram illustrates another example of an extended TAC MAC CE. The UE can perform multi-TRP operations via a first TRP and a second TRP. The MAC CE may contain a TAG ID (TAG ID_P). TAG ID_P may be associated with at least the first TRP (or with at least the first TRP and the second TRP). The MAC CE may contain a first TA command (TAC_TRP1) for the first TRP. The MAC CE may contain a second TA command (TAC_TRP2) for the second TRP. The UE may apply TAC_TRP1 to the first TRP (e.g., the UE determines which TRP is first based on the minimum TCI state ID or spatial relationship information ID associated with the TRP). The UE may apply TAC_TRP2 to the second TRP (e.g., the UE determines which TRP is associated with the second TAC based on the highest TCI state ID or spatial relationship information ID associated with the TRP). The first and / or second TA commands may be relative values ​​used to adjust the current timing advance of the first and / or second TRPs. Alternatively, the first and / or second TA commands may be absolute values ​​for the UE to apply or set timing advances regarding the first and / or second TRPs. The first and second TRPs may be associated with the same serving cell. Alternatively, the second TRP may be associated with at least one non-serving cell, wherein the UE performs inter-cell mTRP operations through at least one serving cell and at least one non-serving cell. Alternatively, the MACCE may contain an offset (Offset_1) for the second TRP. The offset may be the (UL) timing advance difference between TRP1 and TRP2. The UE may apply TAC_TRP 1 to the serving cell (or to the cell associated with TRP1) and apply TAC_TRP2 to the non-serving cell (or apply Offset_1 and / or TAC_TRP1 to the non-serving cell).

[0514] To derive, for example, the timing advance TA2 of a second TRP based on Offset_1, the UE can add Offset_1 to the current (or previous) timing advance TA1 of the first TRP (before applying TAC_TRP1) (e.g., TA2 = TA1 + Offset_1). As another example, the UE can add Offset_1 to the timing advance TA1' of the first TRP derived from the current (or previous) timing advance TA1, thereby applying TAC_TRP1 as indicated in the TAC MAC CE (e.g., TA2 = TA1 + TAC_TRP1 + Offset_1).

[0515] Additionally and / or alternatively, such as Figure 15B As shown, the MAC CE may contain a non-serving cell ID, a non-serving cell id1 (e.g., the PCI of the non-serving cell), and the UE applies Offset1 or TAC_TRP2 (used to adjust the absolute or relative TA value of the current TA) to the non-serving cell associated with the non-serving cell id1.

[0516] Additionally and / or alternatively, such as Figure 15C As shown, the MAC CE may contain more than one offset or TAC for a non-serving cell. The MAC CE may indicate TAC_TRP1 (for the serving cell). The MAC CE may, for example (using PCI non-serving cell id1 and id2), indicate two offsets or TACs for two non-serving cells, and the UE applies Offset_1, Offset_2, or (TAC_TRP2, TAC_TRP3, absolute TA value, or relative TA value used to adjust the current TA) to the indicated non-serving cell.

[0517] Additionally and / or alternatively, such as Figure 15D As shown, the MAC CE may contain more than one offset or TAC for the non-serving cell. The MAC CE may not contain a TAG ID field or TA command for the serving cell. The MAC CE may, for example (using PCI non-serving cell id1 and id2), indicate two offsets or TACs for two non-serving cells, and the UE applies Offset_1, Offset_2, or (TAC_TRP2, TAC_TRP3, absolute TA value, or relative TA value used to adjust the current TA) to the indicated non-serving cell.

[0518] Alternatively, the network may provide the TA for the first TRP and the second TRP to the UE via PDCCH signaling (e.g., DCI) instead of MAC CE.

[0519] Any combination of the following concepts, teachings, or embodiments may be combined with the embodiments and disclosures above and herein to form new embodiments.

[0520] For TA information associated with TRP, the UE can apply the TA information (e.g., derive N). TA and / or N TA,offset Alternatively, the time difference between the UL and DL of the TRP can be derived based on or using TA information.

[0521] For a cell-associated TRP, the TRP can be represented or associated with the cell's Control Resource Set Pool Index. Alternatively, the TRP can be represented or associated with one or more TCI states, SRS resource sets, BFD-RS, or spatial relationship information configured for the cell. Alternatively, the TRP can be associated with the cell's Physical Cell Index or Serving Cell Index.

[0522] To activate a TRP for a UE, the network can activate the TCI state of the UE associated with the TRP. To activate a TRP for a UE used for UL transmission, the network can activate the UL beam or UL TCI state or spatial relationship information associated with the TRP (e.g., the UL beam used to perform PUCCH or PUSCH transmission).

[0523] The first TRP is not synchronized with the second TRP. The first TRP may have different TA information with the second TRP. The serving cell is not synchronized with the non-serving cell. The serving cell may have different TA information with the non-serving cell. For a UE performing an mTRP operation on the first TRP and the second TRP, the UE transmits a Transport Block (TB) to the first TRP (repeatedly) and transmits the same TB to the second TRP. Additionally and / or alternatively, the UE may receive the second TB on the first TRP and receive the same second TB on the second TRP. The first TRP and the second TRP may be associated with the same cell (intra-cell mTRP) or different cells (inter-cell mTRP). The UE may perform UL transmission on one or more TRPs via multiple panels of the UE (e.g., one UL panel corresponds to one TRP for UL transmission). Each of the one or more TRPs may be associated with a cell. A UE performing an mTRP operation may activate more than one TCI state (or spatial relationship information) (simultaneously), each of the more than one TCI state (or spatial relationship information) may be associated with the first TRP or the second TRP. The UE can perform UL or DL ​​communication with the first TRP and the second TRP via more than one active TCI state (or spatial relationship information).

[0524] Each of the more than one TCI state may be associated with a PUSCH or PUCCH, wherein the UE may perform multiple PUCCH and / or PUSCH transmissions to the first and second TRPs via more than one TCI state (or spatial relationship information).

[0525] The TRP mentioned above can be replaced by or associated with a cell's CORESET pool (e.g., coresetPoolIndex). For a UE performing a single TRP operation on a cell, the UE can receive and listen to signaling from the cell via a single CORESET pool. For a UE performing multiple TRP operations on a cell, the UE can receive and listen to signaling from the cell via more than one CORESET pool.

[0526] Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with one or more TCI states of the cell. For a UE performing a single TRP operation on a cell, the UE may receive or listen to signaling on the cell via an active TCI state. For a UE performing multiple TRP operations on a cell, the UE may receive or listen to signaling via more than one active TCI state. Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with an index of an SRS resource.

[0527] Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with the SRS resources (sets) of the cell. For a UE performing a single TRP operation on a cell, the UE may transmit the SRS on the cell via one SRS resource. For a UE performing multiple TRP operations on a cell, the UE may transmit the SRS via more than one SRS resource, each of which may be associated with a (different) TRP.

[0528] TCI status or spatial relationship information may be associated with or indicate a beam or reference signal (e.g., a synchronization signal block (SSB) or a channel state information reference signal (CSI-RS)).

[0529] Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with a PUSCH or PUCCH. For a UE performing intra-cell mTRP operation on a cell, the UE may perform UL transmission via more than one PUSCH associated with the cell. For a UE performing inter-cell mTRP operation on a cell, the UE may perform UL transmission via more than one PUSCH associated with different cells, wherein UL transmission may include transmitting the same TB on different PUSCHs associated with different cells.

[0530] Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with a set of (UL) beams of the cell. For a UE performing a single TRP operation on a cell, the UE may perform UL transmission via a set of (UL) beams. For a UE performing multiple TRP operations on a cell, the UE may perform UL transmission via more than a set of (UL) beams, each of which may be associated with a (different) TRP.

[0531] Additionally and / or alternatively, the TRP mentioned above may be replaced by or associated with spatial relationship information of the cell. For a UE performing a single TRP operation on a cell, the UE may activate one spatial relationship information (of the cell). For a UE performing multiple TRP operations on a cell, the UE may activate more than one spatial relationship information (of the cell), each of which may be associated with a (different) TRP.

[0532] The UE's non-serving cell can be configured with a PCI value different from the UE's serving cell, or associated with a PCI value different from the UE's serving cell. The non-serving cell can be a neighboring cell of the UE.

[0533] The TA information associated with the second TRP (provided by the network) may contain an (absolute) timing advance command (e.g., TA) or N for timing adjustments of UL transmissions on the second TRP. TA (For example, timing advance between downlink and uplink).

[0534] For example, the TA information associated with the second TRP can be a timing advance command TA with a value ranging from 0 to 3846, where for a second TRP with a subcarrier spacing (SCS) of kHz, the amount of time alignment is [value missing]. Alternatively and / or, the TA information associated with the second TRP can be a timing advance command TA in index form (ranging from 0 to 63). The UE can then use the TA to [determine / alternate] the current N [time / time / location]. TA The value is adjusted to the new N. TA The value is given by , where for SCS, the TRP is kHz.

[0535] Alternatively, the TA information associated with the second TRP may contain the N associated with the first TRP. TA and / or N associated with the first TRP TA Associated (timeslot) offset. When the (timeslot) offset is equal to 0, the first TRP and the second TRP have the same timing advance or TA for UL transmission.

[0536] Alternatively, the TA information associated with the second TRP may indicate or contain the cell index of the second TRP or indicate the second TRP. The UE may apply the TA information to the second TRP.

[0537] TA information can include timing advances between downlink and uplink (e.g., N). TA ) and / or a fixed offset used to calculate timing advance (e.g., N) TA,offset UL TA information.

[0538] TRP activation signaling can be TCI status activation / deactivation MAC CE or spatial relationship information activation / deactivation MAC CE.

[0539] The activation signaling for the TRP can be an activation / deactivation DCI indicating the TCI status. The DCI may not contain or indicate UL approval or DL ​​allocation (e.g., beam indication DCI). The activation signaling for the TRP can be an activation / deactivation DCI indicating spatial relationship information or a MAC CE.

[0540] PDCCH signaling can be a new format of PDCCH commands. PDCCH signaling can indicate the cell ID (e.g., PCI) and / or beam (e.g., TCI state ID) and / or TRP ID (e.g., BFD-RS set) of the (first and / or second) TRP. In response to the completion of the random access procedure on the non-serving cell, the UE can perform an SRS delivery on the cell. The UE may not perform an SRS delivery until TA information for the non-serving cell is obtained (even if SRS resources are configured for the non-serving cell).

[0541] The first TRP is not synchronized with the second TRP. The first TRP may have different TA information than the second TRP. The serving cell is not synchronized with the non-serving cell. The serving cell may have different TA information than the non-serving cell.

[0542] TCI status activation MAC CE can be a TCI status indication for UE-specific PDCCH MAC CE.

[0543] TCI state activation MAC CE can activate / deactivate TCI state for UE-specific PDSCH MAC CE.

[0544] The first TRP and the second TRP may not be in the same TAG.

[0545] PDCCH signaling can be PDCCH commands. PDCCH signaling can also be in DCI format, which differs from PDCCH commands.

[0546] The random access procedure can be a contention-based or contention-free random access procedure.

[0547] For TA information associated with a TRP, the UE can maintain a timer for the TA information. The TA information is considered valid while the timer is running. The TA information is considered invalid when the timer expires or is not running. If or when a timing advance command for the TA information of a TRP is received (via MAC CE), the UE can (re)start the timer for the TA information of the TRP (without restarting the timers for the TA information of other TRPs).

[0548] Any combination of the above concepts can be combined together or formed into new embodiments. The following embodiments can be used to at least (but not limited to) solve the problems mentioned above.

[0549] See Figure 16 According to this and other concepts, systems, and methods of the present invention, a method 1000 for a UE in a wireless communication system includes: receiving from a network a configuration of UL resources associated with a first TRP and UL resources associated with a second TRP (step 1002); initiating a first random access procedure on the first TRP, wherein the UE obtains first TA information of the first TRP in the random access procedure (step 1004); receiving from the network a signaling indicating activation of UL communication for the second TRP (step 1006); initiating a second random access procedure on the second TRP in response to the signaling, wherein the UE obtains second TA information of the second TRP in the second random access procedure (step 1008); and transmitting a TB for the first TRP by applying the first TA information and transmitting a TB for the second TRP by applying the second TA information (step 1010).

[0550] In various embodiments, the UE is configured to perform multiple TRP operations on the first TRP and the second TRP.

[0551] In various embodiments, the first TRP is associated with the serving cell.

[0552] In various embodiments, the second TRP and the first TRP are associated with the same serving cell.

[0553] In various embodiments, the second TRP is associated with a non-serving cell.

[0554] In various embodiments, in response to the completion of the second random access procedure, the UE does not treat a non-serving cell as a serving cell.

[0555] In various embodiments, the first and / or second TA information is the timing advance command of the first and / or second TRP.

[0556] In various embodiments, the first and / or second TA information is time alignment, or timing advance (N) between the downlink and uplink of the first and / or second TRP. TA ).

[0557] In various embodiments, when or if TA information associated with the second TRP is provided via the network in the configuration, the UE does not perform a second random access procedure on the second TRP.

[0558] In various embodiments, when or if TA information associated with the second TRP is provided via the network during signaling transmission or before receiving signaling, the UE does not perform a second random access procedure on the second TRP.

[0559] In various embodiments, the UE initiates a first random access procedure in response to a PDCCH command from the network.

[0560] In various embodiments, in response to a connection establishment triggered by the UE, the UE initiates a first random access procedure.

[0561] In various embodiments, the signaling is an activation MAC CE that activates the TCI state associated with the second TRP.

[0562] In various embodiments, the signaling is PDCCH signaling that indicates mTRP operation.

[0563] In various embodiments, signaling indicates or provides PCI.

[0564] In various embodiments, the signaling indicates the serving cell index.

[0565] In various embodiments, the signaling indicates one or more TCI states (e.g., TCI state IDs).

[0566] Return to reference Figure 3 and Figure 4 In one or more embodiments from the UE's perspective, apparatus 300 includes program code 312 stored in memory 310 of the transmitter. CPU 308 can execute program code 312 to: (i) receive from the network a configuration configuring UL resources associated with a first TRP and UL resources associated with a second TRP; (ii) initiate a first random access procedure on the first TRP, wherein the UE obtains first TA information for the first TRP in the random access procedure; (iii) receive from the network a signaling indicating activation of UL communication for the second TRP; (iv) initiate a second random access procedure on the second TRP in response to the signaling, wherein the UE obtains second TA information for the second TRP in the second random access procedure; and (v) transmit a TB for the first TRP by applying the first TA information and for the second TRP by applying the second TA information. Furthermore, CPU 308 can execute program code 312 to perform all the described actions, steps, and methods described above, below, or otherwise herein.

[0567] See Figure 17According to this and other concepts, systems and methods of the present invention, a method 1020 for a UE in a wireless communication system includes: performing UL transmission on a first TRP and a second TRP (step 1022); receiving signaling containing first TA information and second TA information from a network (step 1024); and applying the first TA information to the first TRP and applying the second TA information to the second TRP (step 1026).

[0568] In various embodiments, the first TRP and the second TRP are in different timing advance groups (TAGs).

[0569] In various embodiments, the first TRP and the second TRP are in the same TAG.

[0570] In various embodiments, the first and / or second TA information is the timing advance command of the first and / or second TRP.

[0571] In various embodiments, the first and / or second TA information is time alignment, or timing advance (N) between the downlink and uplink of the first and / or second TRP. TA ).

[0572] In various embodiments, the second TA information is the offset between the timing advance of the first TRP and the timing advance of the second TRP.

[0573] In various embodiments, the first TRP is associated with the serving cell.

[0574] In various embodiments, the second TRP and the first TRP are associated with the same serving cell.

[0575] In various embodiments, the second TRP is associated with a non-serving cell and the first TRP is associated with a serving cell.

[0576] In various embodiments, the UE performs inter-cell mTRP operations on non-serving cells and serving cells.

[0577] In various embodiments, the signaling is MAC CE.

[0578] In various embodiments, the signaling contains the physical cell ID associated with the second TRP.

[0579] Return to reference Figure 3 and Figure 4In one or more embodiments from the UE's perspective, device 300 includes program code 312 stored in memory 310 of the transmitter. CPU 308 can execute program code 312 to: (i) perform UL transmission on a first TRP and a second TRP; (ii) receive signaling containing first TA information and second TA information from the network; and (iii) apply the first TA information to the first TRP and apply the second TA information to the second TRP (step 1024). Furthermore, CPU 308 can execute program code 312 to perform all the described actions, steps, and methods described above, below, or otherwise herein.

[0580] See Figure 18 According to this and other concepts, systems and methods of the present invention, a method 1030 for a UE in a wireless communication system includes: performing an inter-cell mTRP operation on a serving cell and a non-serving cell, wherein the UE maintains a first TA timer for the serving cell and a second TA timer for the non-serving cell (step 1032); and refreshing the HARQ buffer of the non-serving cell in response to the expiration of the first TA timer (step 1034).

[0581] In various embodiments, the second TA timer has not expired when the first TA timer expires.

[0582] In various embodiments, when the first TA timer expires, the UE does not consider the second TA timer to have expired.

[0583] In various embodiments, in response to the expiration of the first TA timer, the UE refreshes the HARQ buffers of the serving cell and non-serving cells.

[0584] In various embodiments, in response to the expiration of the first TA timer, the UE releases the PUCCH for the non-serving cell.

[0585] In various embodiments, in response to the expiration of the first TA timer, the UE clears the PUSCH resources of the CSI report of the non-serving cell.

[0586] In various embodiments, in response to the expiration of the first TA timer, the UE clears the configuration DL allocation and UL grant for the non-serving cell.

[0587] In various embodiments, the serving cell and non-serving cells are in different tags.

[0588] In various embodiments, the serving cell and non-serving cells are in the same tag.

[0589] In various embodiments, the UE maintains the first Nth serving cell TA The second N of non-serving cells TA .

[0590] Return to reference Figure 3 and Figure 4 In one or more embodiments from the UE's perspective, apparatus 300 includes program code 312 stored in the transmitter's memory 310. CPU 308 can execute program code 312 to: (i) perform inter-cell mTRP operations on the serving cell and non-serving cell, wherein the UE maintains a first TA timer for the serving cell and a second TA timer for the non-serving cell; and (ii) refresh the HARQ buffer of the non-serving cell in response to the expiration of the first TA timer. Furthermore, CPU 308 can execute program code 312 to perform all the described actions, steps, and methods described above, below, or otherwise herein.

[0591] See Figure 19 According to this and other concepts, systems and methods of the present invention, a method 1040 for a network in a wireless communication system includes: configuring UL resources associated with a first TRP and UL resources associated with a second TRP for a UE (step 1042); receiving SRS from the UE on the second TRP at an opportune time (step 1044); determining a timing advance command associated with the second TRP of the UE based at least on the opportune time of receiving the SRS (step 1046); and transmitting signaling to the UE, wherein the signaling contains or indicates timing alignment information associated with the second TRP (step 1048).

[0592] In various embodiments, the network further determines timing advance commands based on timing alignment information associated with the first TRP.

[0593] In various embodiments, the UE transmits the SRS at the timing based on the time alignment associated with the first TRP.

[0594] In various embodiments, the time alignment information associated with the second TRP is the offset associated with the time alignment associated with the first TRP.

[0595] In various embodiments, the time alignment associated with the second TRP of the UE is the time alignment associated with the first TRP plus or minus the offset.

[0596] In various embodiments, the signaling includes activation of the second TRP, wherein in response to the signaling, the UE activates the UL transmission via the second TRP.

[0597] In various embodiments, the timing alignment information associated with the second TRP is the timing advance command of the second TRP.

[0598] In various embodiments, the timing alignment information associated with the second TRP is timing alignment, or timing advance (N) between the downlink and uplink of the second TRP. TA ).

[0599] In various embodiments, the UE performs multiple TRP operations on the first TRP and the second TRP.

[0600] In various embodiments, the first TRP and the second TRP are associated with different cells.

[0601] In various embodiments, the first TRP and the second TRP are associated with the same cell.

[0602] In various embodiments, the UE obtains the time alignment associated with the first TRP via a random access procedure.

[0603] In various embodiments, the UE does not obtain the time alignment associated with the second TRP via a random access procedure.

[0604] Return to reference Figure 3 and Figure 4 In one or more embodiments from a network perspective, apparatus 300 includes program code 312 stored in memory 310 of the transmitter. CPU 308 can execute program code 312 to: (i) configure UL resources associated with a first TRP and UL resources associated with a second TRP for the UE; (ii) receive SRS from the UE on the second TRP at a certain time; (iii) determine a timing advance command associated with the second TRP of the UE based at least on the time of receiving the SRS; and (iv) transmit signaling to the UE, wherein the signaling contains or indicates timing alignment information associated with the second TRP. Furthermore, CPU 308 can execute program code 312 to perform all the described actions, steps, and methods described above, below, or otherwise herein.

[0605] See Figure 20 According to this and other concepts, systems and methods of the present invention, a method 1050 for a UE in a wireless communication system includes: receiving from a network a configuration of UL resources associated with a first TRP and UL resources associated with a second TRP (step 1052); receiving from the network signaling indicating activation of the second TRP (step 1054); and determining whether to perform a random access procedure on the second TRP in response to the signaling, at least based on time alignment information associated with the second TRP being provided by the network (step 1056).

[0606] In various embodiments, the UE does not perform a random access procedure on the second TRP when or if the time alignment information associated with the second TRP has been provided by the network (in signaling).

[0607] In various embodiments, the UE does not perform a random access procedure on the second TRP when or if the time alignment information associated with the second TRP has been provided by the network in the signaling.

[0608] In various embodiments, the UE does not perform a random access procedure on the second TRP if or if the time alignment information associated with the second TRP has been provided by the network via the previous signaling prior to signaling transmission.

[0609] In various embodiments, the UE does not perform a random access procedure on the second TRP when or if the time alignment information associated with the second TRP has been provided by the network in the configuration.

[0610] In various embodiments, the UE performs a random access procedure on the second TRP when or if the time alignment information associated with the second TRP has not yet been provided by the network.

[0611] In various embodiments, the UE further determines whether to perform a random access procedure for the second TRP based on whether random access resources are provided for the second TRP (via configuration).

[0612] In various embodiments, when or if random access resources are provided for a second TRP (via configuration), the UE performs a random access procedure for the second TRP.

[0613] In various embodiments, the UE does not perform a random access procedure for the second TRP when or if random access resources are provided for the second TRP (via configuration).

[0614] In various embodiments, the UE performs multiple TRP operations on the first TRP and the second TRP.

[0615] In various embodiments, the first TRP and the second TRP are associated with different cells.

[0616] In various embodiments, the first TRP and the second TRP are associated with the same cell.

[0617] In various embodiments, the timing alignment information associated with the second TRP is the timing advance command of the second TRP.

[0618] In various embodiments, the timing alignment information associated with the second TRP is timing alignment, or timing advance (N) between the downlink and uplink of the second TRP. TA ).

[0619] In various embodiments, the time alignment information associated with the second TRP is the offset associated with the time alignment associated with the first TRP.

[0620] Return to reference Figure 3and Figure 4 In one or more embodiments from the UE's perspective, apparatus 300 includes program code 312 stored in memory 310 of the transmitter. CPU 308 can execute program code 312 to: (i) receive from the network a configuration of UL resources associated with a first TRP and UL resources associated with a second TRP; (ii) receive from the network signaling indicating activation of the second TRP; and (iii) determine, at least based on the time alignment information associated with the second TRP being provided by the network, whether to perform a random access procedure for the second TRP in response to the signaling. Furthermore, CPU 308 can execute program code 312 to perform all the actions, steps, and methods described above, below, or otherwise herein.

[0621] See Figure 21 According to this and other concepts, systems and methods of the present invention, a method 1060 for a UE in a wireless communication system includes: receiving signaling, wherein the signaling indicates the activation of a first TRP and / or is a PDCCH signal (step 1062); determining, based on the signaling, to perform a first random access procedure on the first TRP to obtain first TA information associated with the first TRP (step 1064); and performing a multi-TRP operation on the first TRP associated with the first TA information and a second TRP associated with second TA information (step 1066).

[0622] In various embodiments, the method further includes determining not to execute the first random access procedure if the time alignment timer associated with the first TRP is running.

[0623] In various embodiments, the method further includes obtaining second TA information through a second random access procedure executed on a second TRP.

[0624] In various embodiments, the first TRP and the second TRP are associated with different TAGs.

[0625] In various embodiments, activation of the first TRP is the activation of TCI state or spatial relationship information associated with the first TRP.

[0626] In various embodiments, the first TRP and the second TRP are the TRPs of the same serving cell of the UE.

[0627] In various embodiments, the second TRP is the TRP of the UE's serving cell, and the first TRP is associated with a PCI value different from that of the UE's serving cell.

[0628] In various embodiments, the first TA information is the timing advance between the downlink and uplink of the first TRP, and the second TA information is the timing advance between the downlink and uplink of the second TRP.

[0629] In various embodiments, signaling indicates or provides information about the PCI and / or control resource set pool index and / or BFD-RS set associated with the first TRP.

[0630] In various embodiments, the signaling indicates one or more TCI states and / or one or more SRS resource set identifiers and / or one or more spatial relationship information associated with the first TRP.

[0631] In various embodiments, signaling indicates whether first TA information associated with the first TRP has been obtained.

[0632] In various embodiments, signaling indicates whether a first random access procedure should be performed.

[0633] In various embodiments, the method further includes performing UL transmission on a first TRP by applying first TA information and performing UL transmission on a second TRP by applying second TA information.

[0634] In various embodiments, the first random access procedure is either contention-free or contention-based.

[0635] Return to reference Figure 3 and 4 In one or more embodiments from the UE's perspective, apparatus 300 includes program code 312 stored in memory 310 of the transmitter. CPU 308 can execute program code 312 to: (i) receive signaling indicating the activation of a first TRP and / or a PDCCH signal; (ii) based on the signaling, determine to perform a first random access procedure on the first TRP to obtain first TA information associated with the first TRP; and (iii) perform multiple second TRP operations on the first TRP associated with the first TA information and the second TRP associated with the second TA information. Furthermore, CPU 308 can execute program code 312 to perform all the described actions, steps, and methods described above, below, or otherwise herein.

[0636] Any combination of the concepts or teachings above may be combined together or formed into new embodiments. The disclosed details and embodiments may be used to solve at least (but not limited to) the problems mentioned above and herein.

[0637] It should be noted that any of the methods, alternatives, steps, examples, and embodiments presented herein may be used independently, individually, and / or in combination with multiple methods, alternatives, steps, examples, and embodiments.

[0638] Various aspects of this disclosure have been described above. It should be understood that the teachings herein can be implemented in a wide variety of forms, and any specific structure, function, or both disclosed herein are merely representative. Based on the teachings herein, those skilled in the art will understand that the aspects disclosed herein can be implemented independently of any other aspects, and two or more of these aspects can be combined in various ways. For example, any number of aspects set forth herein can be used to implement an apparatus or practice. Furthermore, this apparatus or practice can be implemented using other structures, functions, or structures and functions other than or different from those set forth herein. As examples of some of the foregoing concepts, in some aspects, a parallel channel can be established based on the pulse repetition frequency. In some aspects, a parallel channel can be established based on the pulse position or offset. In some aspects, a parallel channel can be established based on a time-hopping sequence. In some aspects, a parallel channel can be established based on the pulse repetition frequency, the pulse position or offset, and the time-hopping sequence.

[0639] Those skilled in the art will understand that information and signals can be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the foregoing description can be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, light fields or light particles, or any combination thereof.

[0640] Those skilled in the art will further appreciate that the various illustrative logic blocks, modules, processors, components, circuits, and algorithm steps described in conjunction with the aspects disclosed herein can be implemented as electronic hardware (e.g., digital implementation, analog implementation, or a combination of both, which may be designed using source decoding or some other technique) and have instructions in various forms of program or design code (which, for convenience, may be referred to herein as "software" or "software module"), or a combination of both. To clearly illustrate this interchangeability between hardware and software, the various illustrative components, blocks, modules, circuits, and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends on the specific application and the design constraints imposed on the system as a whole. Those skilled in the art may implement the described functionality in different ways for each specific application, but such implementation decisions should not be construed as causing a deviation from the scope of this disclosure.

[0641] Additionally, the various illustrative logic blocks, modules, and circuits described in connection with the aspects disclosed herein may be implemented within, or executed by, an integrated circuit (“IC”), an access terminal, or an access point. An IC may include a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, electrical components, optical components, mechanical components, or any combination thereof designed to perform the functions described herein, and may execute code or instructions residing within, outside, or both of the IC. A general-purpose processor may be a microprocessor; however, alternatively, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices, such as a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors incorporating a DSP core, or any other such configuration.

[0642] It should be understood that any particular order or hierarchy of steps in any disclosed process is an instance of a sample method. It should be understood that a particular order or hierarchy of steps in the process may be rearranged based on design preferences while remaining within the scope of this disclosure. The appended method claims present the elements of the various steps in a sample order, but are not intended to limit us to the particular order or hierarchy presented.

[0643] The steps of the methods or algorithms described in conjunction with the aspects disclosed herein can be implemented directly in hardware, as a software module executed by a processor, or in a combination of both. The software module (e.g., containing executable instructions and associated data) and other data can reside in a data memory, such as RAM, flash memory, ROM, EPROM, EEPROM, registers, hard disk, removable disk, CD-ROM, or any other form of computer-readable storage media known in the art. The sample storage media can be coupled to a machine such as a computer / processor (for convenience, this machine may be referred to herein as a "processor") such that the processor can read information (e.g., code) from the storage media and write information to the storage media. The sample storage media can be integrated with the processor. The processor and storage media can reside in an ASIC. The ASIC can reside in a user equipment. Alternatively, the processor and storage media can reside as discrete components in a user equipment. Furthermore, in some aspects, any suitable computer program product may include a computer-readable medium comprising code associated with one or more aspects of this disclosure. In some respects, computer program products may include packaging materials.

[0644] Although the invention has been described in conjunction with various aspects and examples, it should be understood that further modifications can be made to the invention. This application is intended to cover any changes, uses, or adaptations of the invention that generally follow the principles of the invention and include such deviations from this disclosure, which fall within the scope of known and common practice in the technical field to which this invention pertains.

Claims

1. A method for a user equipment, characterized in that, include: Receive physical downlink control channel signals, wherein the physical downlink control channel signals indicate or provide information about the physical cell identifier; Based on the information indicated or provided by the physical downlink control channel signal, a first random access procedure is initiated in a cell having a physical cell identifier that is different from the physical cell identifier of the serving cell of the user equipment, in order to obtain or derive first time alignment information associated with at least one first transport configuration indicator state of the cell having the physical cell identifier; as well as Multiple transceiver point operation is performed using at least one first transmission configuration indicator state associated with the first time alignment information and at least one second transmission configuration indicator state of the serving cell of the user equipment associated with the second time alignment information, wherein the first time alignment information and the second time alignment information are maintained or configured to be in different groups of N. TA and / or N TA,offset .

2. The method according to claim 1, characterized in that, It further includes receiving a media access control element, wherein the media access control element includes a timing advance group identifier field indicating the identifier of the timing advance group and a timing advance command field indicating the absolute timing advance of the transceiver point.

3. The method according to claim 1, characterized in that, This further includes obtaining the second time alignment information during a second random access procedure.

4. The method according to claim 1, characterized in that, The at least one first transport configuration indicator state and the at least one second transport configuration indicator state are associated with different timing advance groups.

5. The method according to claim 1, characterized in that, It further includes applying the first time alignment information to uplink transmissions performed via the state of the at least one first transmission configuration indicator.

6. The method according to claim 1, characterized in that, It further includes applying the second time alignment information to uplink transmissions performed via the state of the at least one second transmission configuration indicator.

7. The method according to claim 1, characterized in that, The timing alignment information contains timing advance between the downlink and uplink and / or a fixed offset used to calculate the timing advance.

8. The method according to claim 1, characterized in that, The physical downlink control channel signal indicates whether the first time alignment information associated with the state of the at least one first transport configuration indicator has been obtained.

9. The method according to claim 1, characterized in that, The first random access procedure is either contention-free or contention-based.

10. A user equipment, characterized in that, include: Memory; as well as A processor operatively connected to the memory, wherein the processor is configured to execute program code to: Receive physical downlink control channel signals, wherein the physical downlink control channel signals indicate or provide information about the physical cell identifier; Based on the information indicated or provided by the physical downlink control channel signal, a first random access procedure is initiated in a cell having a physical cell identifier that is different from the physical cell identifier of the serving cell of the user equipment, in order to obtain or derive first time alignment information associated with at least one first transport configuration indicator state of the cell having the physical cell identifier; as well as Multiple transceiver point operation is performed using at least one first transmission configuration indicator state associated with the first time alignment information and at least one second transmission configuration indicator state of the serving cell of the user equipment associated with the second time alignment information, wherein the first time alignment information and the second time alignment information are maintained or configured to be in different groups of N. TA and / or N TA,offset .

11. The user equipment according to claim 10, characterized in that, The processor is further configured to execute the program code to receive a media access control element, wherein the media access control element includes a timing advance group identifier field indicating the identifier of the timing advance group and a timing advance command field indicating the absolute timing advance of the transceiver point.

12. The user equipment according to claim 10, characterized in that, The at least one first transport configuration indicator state and the at least one second transport configuration indicator state are associated with different timing advance groups.

13. The user equipment according to claim 10, characterized in that, The processor is further configured to execute the program code to obtain the second time alignment information in a second random access procedure.

14. The user equipment according to claim 10, characterized in that, The processor is further configured to execute the program code to apply the first time alignment information to an uplink transmission performed via the state of the at least one first transmission configuration indicator.

15. The user equipment according to claim 10, characterized in that, The processor is further configured to execute the program code to apply the second time alignment information to an uplink transmission performed via the state of the at least one second transmission configuration indicator.

16. The user equipment according to claim 10, characterized in that, The timing alignment information contains timing advance between the downlink and uplink and / or a fixed offset used to calculate the timing advance.

17. The user equipment according to claim 10, characterized in that, The physical downlink control channel signal indicates whether the first time alignment information associated with the state of the at least one first transport configuration indicator has been obtained.

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