Systems, methods, and apparatus for enabling multiple timing advances for multiple transmit receive points in wireless communications

Abstract

Systems, methods, and apparatus for enabling multiple timing advances (TAs) for multiple transmit receive points (TRPs) are disclosed herein. In an embodiment, a UE can perform timing advance group (TAG) association for different uplink (UL) transmissions for mTRP use, where a pair of inter-frequency TAGs, respectively corresponding to a pair of TRPs, is used by the UE to determine the TA for UL transmissions to each TRP. In an embodiment, a UE performs downlink (DL) reference timing determinations for two TAs for mTRP use, where such determinations are based on one or more aspects of one or more active transmission configuration indication identifications (TCIs) available for UL at the UE. In an embodiment, the UE handles cases of overlapping UL transmissions on two respective UL panels due to the use of two TAs corresponding to a pair of TRPs. Network behavior and signaling corresponding to these aspects are also discussed.

Description

Technical Field

[0001] The present patent application as a whole relates to wireless communication systems, including wireless communication systems for UEs operating between multiple TRPs. Background Art

[0002] Wireless mobile communication technologies use various standards and protocols to send data between base stations and wireless communication devices. For example, wireless communication system standards and protocols may include the Third Generation Partnership Project (3GPP) Long Term Evolution (LTE) (e.g., 4G), 3GPP New Radio (NR) (e.g., 5G), and the Institute of Electrical and Electronics Engineers (IEEE) 802.11 standard for wireless local area networks (WLANs) (commonly referred to within industry organizations as WLANs). ).

[0003] As envisioned by 3GPP, different wireless communication system standards and protocols may use various radio access networks (RANs) to communicate between base stations of the RAN (which may also sometimes be referred to as RAN nodes, network nodes, or simply nodes) and wireless communication devices referred to as user equipment (UE). 3GPP RANs may include, for example, Global System for Mobile Communications (GSM), Enhanced Data Rates for GSM Evolution (EDGE) RAN (GERAN), Universal Terrestrial Radio Access Network (UTRAN), Evolved Universal Terrestrial Radio Access Network (E-UTRAN), and / or Next Generation Radio Access Network (NG-RAN).

[0004] Each RAN may use one or more radio access technologies (RATs) to perform communications between base stations and UEs. For example, GERAN implements GSM and / or EDGE RAT, UTRAN implements Universal Mobile Telecommunications System (UMTS) RAT or other 3GPP RAT, E-UTRAN implements LTE RAT (sometimes referred to as LTE), and NG-RAN implements NR RAT (sometimes referred to herein as 5G RAT, 5G NR RAT, or NR). In some deployments, E-UTRAN may also implement NR RAT. In some deployments, NG-RAN may also implement LTE RAT.

[0005] The base stations used by the RAN may correspond to the RAN. An example of an E-UTRAN base station is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN) Node B (also commonly denoted as an evolved Node B, enhanced Node B, eNode B, or eNB). An example of an NG-RAN base station is a Next Generation Node B (sometimes also referred to as a gNode B or gNB).

[0006] The RAN provides communication services together with external entities through its connection with the Core Network (CN). For example, E-UTRAN may utilize the Evolved Packet Core (EPC) and NG-RAN may utilize the 5G Core Network (5GC).

[0007] The frequency bands of 5G NR can be divided into two or more different frequency ranges. For example, frequency range 1 (FR1) may include frequency bands operating at frequencies below 6 gigahertz (GHz), some of which are available for use by previous standards and can potentially be expanded to cover new spectrum products from 410 megahertz (MHz) to 7125MHz. Frequency range 2 (FR2) may include frequency bands from 24.25GHz to 52.6GHz. It should be noted that in some systems, FR2 may also include frequency bands from 52.6GHz to 71GHz (or higher). The frequency bands in the millimeter wave (mmWave) range of FR2 may have smaller coverage than the frequency bands in FR1 but potentially higher available bandwidth. The technician will recognize that these frequency ranges provided by way of example may change over time or region. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] To easily identify the discussion of any particular element or action, the most significant digit(s) in a reference number refers to the drawing number that first introduces the element.

[0009] Figure 1 A template for TAG configuration according to an embodiment of the present invention is shown.

[0010] Figure 2 A diagram corresponding to the use of TAG configuration in the UL mTRP case according to an embodiment of this document is shown.

[0011] Figure 3 A method for a UE to handle TAT timer expiration according to an embodiment of this document is shown.

[0012] Figure 4 A template for configuration of a CG for implementing RRC-based HARQ buffer sharing indication according to the implementation scheme of this document is shown.

[0013] Figure 5 A template for TCI state configuration including TAG-ID according to an embodiment of this document is shown.

[0014] Figure 6 A template for TAG configuration according to an embodiment of the present invention is shown, which shows that the TAG configuration can include a coresetPoolIndex value for the corresponding TAG.

[0015] Figure 7A table according to an embodiment of the present invention is shown, which provides examples of TAG associations corresponding to a certain number of TCI states.

[0016] Figure 8 A method of a UE according to an embodiment of this document is shown.

[0017] Fig. 9 A method of a RAN according to an embodiment of the present invention is shown.

[0018] Fig.10 A table showing information corresponding to various alternatives for determining DL reference timing for TA commands according to embodiments herein is shown.

[0019] Fig.11 A method of a UE according to an embodiment of this document is shown.

[0020] Fig.12 A method of a UE according to an embodiment of this document is shown.

[0021] Fig.13 A method of a UE according to an embodiment of this document is shown.

[0022] Fig.14A A diagram showing a manner of dropping data of one UL transmission with respect to an overlap between time slots of two UL transmissions at different UL panels for a UE according to embodiments herein is shown.

[0023] Fig. 14B A diagram showing a manner of dropping data of one UL transmission with respect to an overlap between time slots of two UL transmissions at different UL panels for a UE according to embodiments herein is shown.

[0024] Fig.15 A method of a UE according to an embodiment of this document is shown.

[0025] Fig.16 A method of a UE according to an embodiment of this document is shown.

[0026] Fig.17 A method of a RAN according to an embodiment of the present invention is shown.

[0027] Fig.18 A method of a RAN according to an embodiment of the present invention is shown.

[0028] Fig.19 An exemplary architecture of a wireless communication system according to embodiments disclosed herein is shown.

[0029] Fig. 20A system for performing signaling between a wireless device and a network device according to embodiments disclosed herein is shown. DETAILED DESCRIPTION

[0030] Various embodiments are described with respect to UE. However, reference to UE is provided for illustrative purposes only. The example embodiments may be used with any electronic component that can establish a connection with a network and is configured with hardware, software, and / or firmware for exchanging information and data with the network. Therefore, UE as described herein is used to represent any suitable electronic component.

[0031] New mobile services corresponding to low latency and high reliability performance use cases (e.g., ultra-reliable low latency communications (URLLC)) are emerging. Accordingly, wireless communication systems (e.g., wireless communication systems implementing the 5G standard) are advantageous for enhancing mobility robustness and performance within such scenarios.

[0032] Uplink (UL) timing enhancements that advance these goals may accordingly be advantageous. It has been determined that multiple-input multiple-output (MIMO) evolution for downlink (DL) and UL may specify cases where two timing advances (TAs) in the UL may be used for multiple downlink control information (DCI) (mDCI) for multiple transmission reception points (TRPs) (mTRPs). Additionally, it has been determined that such MIMO evolution may specify mechanisms and procedures for layer 1 (L1) / layer 2 (L2) based inter-cell mobility to achieve mobility delay reduction, such as TA management mechanisms and procedures in such cases.

[0033] A UE may be configured with a pair of timing advance groups (TAGs). A first of the TAGs may be associated with UL communications made by the UE for a first TRP, and a second of the TAGs may be associated with UL communications made by the UE for a second TRP. In some cases, UL communications for the first TRP are performed by the UE using a first UL panel of the UE, and UL communications for the second TRP are performed by the UE using a second UL panel of the UE.

[0034] Each TAG in the pair of TAGs may be associated with communicating with its corresponding TRP using the same frequency. Such TAGs associated with the use of the same frequency may be referred to herein as "intra-frequency TAGs". When an UL transmission is performed using frequencies corresponding to two intra-frequency TAGs configured at the UE for two different TRPs, the UE may identify one of the two TAGs as being associated with the UL transmission and perform the UL transmission in accordance with that TAG. This enables the UL transmission to be appropriately configured for reception at the TRP for that TAG.

[0035] Each of the first TAG and the second TAG may use a (e.g., different) TA value (e.g., corresponding to a different distance of the UE from each of the TRPs). Thus, a first UL transmission for a first TRP may be sent at a timing determined using a first TA value of the first TAG, and a second UL transmission for a second TRP may be sent at a timing determined using a second TA value of the second TAG.

[0036] The TAG may be understood / defined at the UE (at least in part) based on a TAG configuration for the TAG provided to the UE by the network. Figure 1 A template 100 for TAG configuration according to an embodiment of the present invention is shown. Note that the template 100 may be a template for ASN.1 configuration used, for example, by a UE. The template 100 shows that the TAG configuration may include a dedicated TAG identification (TAG-ID) 102 for the corresponding TAG and one or more time alignment timer (TAT) values ​​104 corresponding to the TAG usage identifying the length of time that the TA corresponding to the TAG is valid.

[0037] Figure 2 A diagram 200 is shown corresponding to the use of TAG configuration in a UL mTRP case according to an embodiment of the present invention. Diagram 200 shows a UE 202 performing UL communication with a first TRP 204 (associated with a first TAG 208) and with a second TRP 206 (associated with a second TAG 210), the second TAG being an intra-frequency TAG relative to the first TAG 208.

[0038] The embodiments discussed herein may relate to intra-frequency TAG usage for multiple TRPs in an inter-cell case and / or an intra-cell case. In the inter-cell case, the UE is connected to each of the TRPs (on the same frequency) on different cells (e.g., with different physical cell identities (PCIs)). Figure 2 Such an inter-cell situation is shown because UE 202 is connected to a UE with a first PCI ( Figure 2 The UE is also connected to the first TRP 204 on the first cell 212 with a second PCI ( Figure 2 The second TRP 206 is connected on the second cell 214 of the "PCI-2" in the example.

[0039] In the intra-cell case, the UE connects / is connected to each of the TRPs on the same cell (eg, each of these TRPs broadcasts the same cell (with the same PCI) for use by the UE).

[0040] Unless the specific context of the described embodiments makes it otherwise clear, it should be understood that the discussion herein can be applied to both inter-cell cases and intra-cell cases.

[0041] Figure 2 The first TAG 208 is shown experiencing mobility 216 relative to the first TRP 204 and the first TAG 208. In the inter-cell case, communication with one of these TRPs can occur on a "serving cell", which can be a cell to which the UE is / was already connected (e.g., before / regardless of any mobility). Additionally, in such an inter-cell case, communication with another of these TRPs can occur on a "non-serving cell", which can be a cell to which the UE is initiating a new connection (e.g., until a new cell broadcast by this second TRP is coming into range due to mobility). Accordingly, relative to Figure 2 , and assuming an existing connection with a first TRP 204 on a first cell 212, when the UE 202 undergoes mobility 216, the UE 202 initiates a (further) connection with a second TRP 206 on a second cell 214 corresponding to the mTRP usage as described herein. In such a case, the first cell 212 will be understood as a "serving cell" and the second cell 214 will be understood as a "non-serving cell".

[0042] TAG association for different UL transmissions for mDCI mTRP

[0043] The first problem that arises when using two TAs for UL mDCI mTRPs relates to the way in which different TAs are taken into account for UL transmissions towards different TRPs. For example, it may be necessary to define a way in which TA values ​​are determined for different UL transmissions towards different TRPs.

[0044] The embodiments herein enable association of TA values ​​with UL transmissions in the case of mTRP via the use of TAGs. Accordingly, various aspects related to association between UL transmissions and corresponding intra-frequency TAGs (eg, where each intra-frequency TAG uses a corresponding (eg, different) TA) are now discussed.

[0045] In some embodiments, the TAG list may be provided to the UE via radio resource control (RRC) signaling from the network. The TAG list may include TAG configurations for TAGs of cells corresponding to a cell group (eg, a master cell group (MCG) or a serving cell group (SCG)).

[0046] In some designs, the maximum number of TAG configurations indicated in the TAG list may be greater than four. For example, in some cases, (up to) eight TAG configurations may be indicated in the TAG list. It is noted that the use of (up to) eight TAG configurations in the TAG list may be an improvement from previous wireless communication systems, which may allow (e.g.) only (up to) four such TAG configurations.

[0047] A UE capability may be introduced to indicate the maximum number of TAGs supported by the UE. The UE may indicate this capability to the network in a UE capability message. In some designs, the network may accordingly limit the number of TAG configurations sent in the TAG list to be less than or equal to the indicated UE capability.

[0048] For the TAG configuration of the TAG list for a pair of intra-frequency TAGs, multiple options for the configuration of the TAT may be considered. In a first option, two independent timeAlignmentTimer parameters for respective (e.g., different) TATs may be configured in the TAG configuration of the TAG list for two intra-frequency TAGs, such that one TAG in the intra-frequency TAG uses one TAT in the TATs and the other TAG in the intra-frequency TAG uses the other TAT in the TATs.

[0049] In the second option, a single timeAlignmentTimer parameter with TAT may be explicitly configured via RRC signaling in the TAG configuration of the TAG list for one of the two intra-frequency TAGs. Based on this explicit indication of the TAT for one of the intra-frequency TAGs, the UE may use the (same) TAT for the other intra-frequency TAG in the intra-frequency TAG.

[0050] exist Figure 2 In the embodiment of the present invention, the UE 202 has been configured by the network with a TAG list 218. As shown, up to eight TAG configurations may be configured for the UE 202 in the TAG list 218 (eg, subject to the UE capabilities of the UE 202 as discussed herein). Figure 2 Accordingly, the TAG list 218 is shown to have eight TAG configurations, which have indices from 0 to 7.

[0051] As shown, the first TAG 208 corresponds to the index 1 TAG configuration 220 of the TAG list 218, and the second TAG 210 corresponds to the index 3 TAG configuration 222, in which case the first TAG 208 and the second TAG 210 are intra-frequency TAGs. The index 1 TAG configuration 220 and the index 3 TAG configuration 222 may have been selected based on communication between the UE and the network.

[0052] In some embodiments, as discussed herein, each of the index 1TAG configuration 220 and the index 3TAG configuration 222 may be configured with a separate TAT. Accordingly, the UE 202 uses the TAT given in the index 1TAG configuration 220 together with the TA mechanism for UL transmissions to the first TRP 204 according to the first TAG 208. In addition, the UE 202 uses the TAT given in the index 3TAG configuration 222 together with the TA mechanism for UL transmissions to the second TRP 206 according to the second TAG 210.

[0053] In other cases, as discussed herein, the network may configure one of the index 1 TAG configuration 220 for the first TAG 208 and the index 3 TAG configuration 222 for the second TAG 210 with an explicit TAT for use with the TA mechanism for UL transmissions to the first TRP 204 according to the first TAG 208. Thereafter, based on the fact that the first TAG 208 and the second TAG 210 are intra-frequency TAGs, the UE 202 thereafter applies the same TAT for use with the TA mechanism for UL transmissions to the second TRP 206 according to the second TAG 210. Using such an implicit approach (for at least one of the TAGs) may minimize signaling overhead relative to the case where multiple TATs are explicitly indicated.

[0054] Various options for UE behavior when one or more TAT timers expire are now discussed. Figure 3 A method 300 for a UE handling a TAT timer expiration according to embodiments herein is shown.

[0055] When the TAT corresponding to the TAG times out 302, the UE may notify 304 the network (e.g., via RRC) to release any physical uplink control channel (PUCCH) / sounding reference signal (SRS) / DL semi-persistent scheduling (SPS) resources used for semi-persistent channel state information (SP-CSI) reporting corresponding to the TAG and any configured grant (CG) physical uplink shared channel (PUSCH) and / or PUSCH resources. The TA value (e.g., N TAG) corresponding to the TAG may be maintained at the UE. TA value).

[0056] In addition, when the TAT for the TAG times out, the hybrid automatic repeat request (HARQ) buffer of the serving cell may be processed at the UE as follows. In the first case, the UE determines 306 that the HARQ buffers are shared between this TAG associated with two UL panels and a second intra-frequency TAG relative to the TAG. The use of such shared HARQ buffers may correspond to a situation where a single (same) distributed unit (DU) corresponds to each TRP, such that the backhaul (BH) for the first TRP and the second TRP is as practically ideal between these TRPs. In the case where shared HARQ buffers are being used, the UE then checks 308 whether both TAT timers have timed out (e.g., the UE checks 308 whether the second TAT corresponding to the intra-frequency TAG relative to this TAG has also timed out). If both TATs (for each intra-frequency TAG) have timed out, the UE flushes 310 the shared HARQ buffers for each TGA in the TAG.

[0057] In the second case, the UE determines 306 that the HARQ buffers are not shared between this TAG associated with the two UL panels and the second intra-frequency TAG relative to this TAG. The use of independent HARQ buffers may correspond to the case where a different DU corresponds to each TRP, and such BH characteristics applicable to the first TAG are not the same as the BH characteristics applicable to the second TAG. In this case, the UE refreshes 310 the HARQ buffers corresponding to the TAG with the expired TAT timer (on an individual basis).

[0058] In some cases, whether the HARQ buffers for two intra-frequency TAGs are shared may be explicitly configured on a per-cell group basis through RRC signaling from the network to the UE. Figure 4 A template 400 for configuring a cell group for implementing an RRC-based HARQ buffer sharing indication according to an embodiment of the present invention is shown. Note that the template 400 may be a template for an ASN.1 configuration used, for example, by a UE. The template 400 provides a sharedHARQTwoTAGs indication 402, such as Figure 4 As shown, the sharedHARQTwoTAGs indication 402 indicates whether the HARQ buffer is shared by two intra-frequency TAGs.

[0059] An alternative scheme used by the UE to associate a TAG configuration for a TAG from a TAG list with a specific UL transmission to a TRP (such that the UL transmission is sent according to that TAG) is now discussed.

[0060] In a first alternative, an UL transmission at a UE may be associated with a transmission configuration indicator (TCI) state to be used for the UL transmission. For example, the UL transmission may be associated with one of a joint UL / DL TCI state and / or a UL TCI state that controls various aspects of the UL transmission. Such a TCI state may have been previously configured for the UE or activated at the UE. In some cases, the TCI state to be used for the UL transmission is indicated by a DCI format that schedules the UL transmission.

[0061] For each joint UL / DL state or UL TCI state, the TAG-ID associated with one of the two intra-frequency TAGs may be explicitly provided to the UE from the network through RRC signaling. Figure 5 Templates 502, 504 for TCI state configuration including TAG-ID according to embodiments herein are shown.

[0062] The first template 502 corresponds to a configuration for a joint UL / DL TCI state and illustrates that the configuration for the joint UL / DL TCI state may include a TAG-ID 506. Note that the first template 502 may be a template for an ASN.1 configuration used, for example, by a UE. When the UE identifies that a UL transmission will be sent according to a joint UL / DL TCI state configured with the TAG-ID 506, the UE associates the UL transmission with the TAG corresponding to the TAG-ID 506.

[0063] The second template 504 corresponds to a configuration for a UL TCI state and shows that the configuration for the UL TCI state may include a TAG-ID 508. Note that the second template 504 may be a template for an ASN.1 configuration used, for example, by a UE. When the UE identifies that a UL transmission will be sent according to a UL TCI state configured with the TAG-ID 508, the UE associates the UL transmission with the TAG corresponding to the TAG-ID 508.

[0064] Note that in some cases, in order to address the TAG number limitation at the UE, a single TAG-ID may be configured for all non-serving cells (because in this case only one TCI state out of seven non-serving cells may be activated).

[0065] Once the TAG associated with the TCI state of the UL transmission is determined, the UE adjusts the uplink timing for the UL transmission (eg, PUSCH / SRS / PUCCH transmission) based on the TA value for this corresponding TAG.

[0066] In a second alternative, a control resource set (CORESET) used by a UE (e.g., to receive a physical downlink control channel (PDCCH)) may be associated with a different CORESET pool corresponding to a corresponding coresetPoolIndex value. In this case, a coresetPoolIndex value of "0" or "1" corresponding to each TAG configuration may be provided to the UE via RRC signaling.

[0067] Figure 6 600 for TAG configuration according to embodiments of the present invention, the template shows that the TAG configuration may include a coresetPoolIndex value 602 for the corresponding TAG. Note that the template 600 may be a template for ASN.1 configuration used, for example, by a UE. As discussed herein, the template 600 may be Figure 1 A further specified version of template 100.

[0068] Thereafter, for UL transmissions scheduled by a UL grant, the UE uses the TA of the TAG associated with the same coresetPoolIndex value as the CORESET in which the UE detected the DCI format carrying the UL grant in the monitored search space.

[0069] For UL transmissions without UL grant (e.g., Type 1 CG-PUSCH, or PUCCH for periodic channel state information (P-CSI) / SP-CSI / periodic sounding reference signal (P-SRS)), the associated coresetPoolIndex value to be used corresponding to such transmissions may be indicated via RRC signaling (e.g., a configuration provided by RRC signaling). Alternatively, a TAG-ID corresponding to such transmission may be provided via RRC signaling (e.g., a configuration provided by RRC signaling), followed by the TA of that TAG being used.

[0070] Note that in some cases (and such as Figure 6 ), if the coresetPoolIndex field is not present in the TAG configuration for a TAG, then the default coresetPoolIndex value (e.g., "0") can be assumed to be the applicable coresetPoolIndex for that TAG. In such cases, in TAG configurations where the default coresetPoolIndex is applicable, the explicit indication of coresetPoolIndex can be intentionally discarded / not used in order to minimize signaling overhead.

[0071] Once the TAG associated with the applicable coresetPoolIndex is determined, the UE adjusts the uplink timing for the UL transmission (eg, PUSCH / SRS / PUCCH transmission) based on the TA value for this corresponding TAG.

[0072] In a third alternative, the UE may identify a TAG associated with an UL transmission based on a path loss (PL) reference signal (RS) of the indicated TCI state. As described herein, a UE may be configured with various TCI states (joint UL / DL TCI states, UL TCI states) that may be used to determine characteristics for UL transmissions. Such a TCI state may indicate a PL RS associated with the TCI state.

[0073] For UL transmission, such as between two intra-frequency TAGs, when (for example) the PL RS of the TCI state for UL transmission is a synchronization signal block (SSB) associated with a non-serving cell or a channel state information reference signal (CSI-RS) with a scrambling identifier (ID) configured through RRC signaling that is different from the scrambling ID used by the PCI of the serving cell, the TAG with the larger TAG-ID is associated with the UL transmission. Otherwise, the TAG with the smaller TAG-ID is associated with the UL transmission.

[0074] Figure 7 A table 700 according to an embodiment of the present invention is shown, which provides an example of TAG associations corresponding to a certain number of UL TCI states 702. Assume that two intra-frequency TAGs for communicating with two TRPs at the UE are configured as TAG#2 and TAG#6 through RRC signaling.

[0075] It is further assumed that four UL TCI states 702 that can be used for UL transmissions are configured to the UE or activated at the UE.It should be appreciated that in other embodiments, one or more of the UL TCI states 702 may instead be joint UL / DLTCI states, as already described.

[0076] By comparing the UL TCI state 702, PL RS 704 and PL RS information 706 in Table 700, it can be seen that the PL RS of UL TCI state #1 is the SSB of the serving cell, the PL RS of UL TCI state #2 is the SSB of the non-serving cell, the PL RS of UL TCI state #3 is the first CSI-RS that does not use a scrambling ID different from the scrambling ID used by the PCI of the serving cell, and the PL RS of UL TCI state #4 is the second CSI-RS that uses a scrambling ID different from the scrambling ID used by the PCI of the serving cell.

[0077] In such a case, using the exemplary rules given above, UL TCI state #1 is associated with the TAG with a smaller ID (TAG #2, as shown in TAG-ID information 708) because its PL RS is the SSB of the serving cell. Accordingly, UL transmission using UL TCI state #1 is associated with TAG #2.

[0078] In addition, UL TCI state #2 is associated with a TAG with a larger ID (TAG #6, as shown in TAG-ID information 708) because its PL RS is the SSB of a non-serving cell. Accordingly, UL transmission using UL TCI state #2 is associated with TAG #6.

[0079] In addition, UL TCI state #3 is associated with a TAG with a smaller ID (TAG #2, as shown in TAG-ID information 708) because its PL RS is a CSI-RS that does not have a scrambling ID different from the PCI of the serving cell. Accordingly, UL transmission using UL TCI state #3 is associated with TAG #2.

[0080] Finally, UL TCI state #4 is associated with a TAG with a larger ID (TAG #6, as shown in TAG-ID information 708) because its PL RS is a CSI-RS with a scrambling ID different from the PCI of the serving cell. Accordingly, UL transmission using UL TCI state #4 is associated with TAG #6.

[0081] Accordingly, for UL transmission, the UE may identify a TAG corresponding to one of the UL TCI states 702 used by the UL transmission. Accordingly, the UE adjusts the uplink timing for UL transmission (e.g., PUSCH / SRS / PUCCH transmission) based on the TA value for the corresponding TAG.

[0082] Contact Exemplary Figure 7 The rules of application are given by way of example and not by way of limitation. For example, in other embodiments, in the case where the PL RS of the TCI state for UL transmission is an SSB associated with a non-serving cell or a CSI-RS with a scrambling ID different from the PCI of the serving cell configured by RRC signaling, otherwise a TAG with a larger TAG-ID is associated with the UL transmission, such as between two intra-frequency TAGs, a TAG with a smaller TAG-ID can be associated with the UL transmission.

[0083] Figure 8A method 800 of a UE according to an embodiment of the present invention is shown. The method 800 includes receiving 802 from a network a first configuration for a first TAG and a second configuration for a second TAG, the first TAG being used by the UE in the UL to communicate with a first TRP of the network using a frequency, and the second TAG being used by the UE in the UL to communicate with a second TRP of the network using the frequency.

[0084] The method 800 also includes identifying 804 that a first UL transmission using the frequency is associated with a first TAG.

[0085] The method 800 also includes performing 806 a first UL transmission at a first time determined based on a first fixed TA value for the first TAG.

[0086] In some embodiments, method 800 also includes identifying that a second UL transmission using the frequency is associated with a second TAG and performing the second UL transmission at a second time determined based on a second TA value for the second TAG.

[0087] In some embodiments of method 800, a first configuration for a first TAG and a second configuration for a second TAG are received in a TAG list including a plurality of configurations for a plurality of TAGs, the plurality of TAGs including the first TAG and the second TAG. In some such embodiments, method 800 further includes: sending a UE capability message to the network, the UE capability message indicating a maximum number of the plurality of TAGs that can be supported by the UE.

[0088] In some embodiments of method 800, the first configuration for the first TAG includes a first time alignment timer for the first TAG, and the second configuration for the second TAG includes a second time alignment timer for the second TAG.

[0089] In some embodiments of method 800, the first configuration for the first TAG includes a first time alignment timer for the first TAG, and method 800 also includes determining that the first time alignment timer is also used for the second TAG.

[0090] In some embodiments, method 800 also includes: identifying that a first HARQ buffer of the UE and a second HARQ buffer of the UE are shared across a first TAG and a second TAG; determining that a first time alignment timer for the first TAG has expired and a second time alignment timer for the second TAG has expired; and in response to determining that the first time alignment timer for the first TAG has expired and the second time alignment timer for the second TAG has expired, refreshing each of the first HARQ buffer and the second HARQ buffer.

[0091] In some embodiments, method 800 also includes: identifying that the UE's first HARQ buffer and the UE's second HARQ buffer are not shared across the first TAG and the second TAG; determining that the time alignment timer for the first TAG has expired; and refreshing the first HARQ buffer in response to determining that the time alignment timer for the first TAG has expired.

[0092] In some embodiments of method 800, identifying that the first UL transmission is associated with the first TAG includes determining that a TAG identifier of the first TAG is associated with a first TCI state indicated as being used for the first UL transmission by a DCI format scheduling the first UL transmission.

[0093] In some embodiments of method 800, a first configuration for a first TAG identifies a CORESET pool associated with the first TAG, and identifying that the first UL transmission is associated with the first TAG includes determining that a DCI format scheduling the first UL transmission is received in a CORESET in the CORESET pool associated with the first TAG.

[0094] In some embodiments of method 800, the first UL transmission is an unlicensed UL transmission, and identifying that the first UL transmission is associated with the first TAG includes determining that a configuration at the UE for the unlicensed UL transmission identifies a CORESET pool associated with the first TAG at the UE.

[0095] In some embodiments of method 800, the first UL transmission is an unlicensed UL transmission, and identifying that the first UL transmission is associated with the first TAG includes determining that a configuration for the unlicensed UL transmission identifies a TAG identifier associated with the first TAG at the UE.

[0096] In some embodiments of method 800, identifying that the first UL transmission is associated with the first TAG includes determining that a first TAG identifier identifying the first TAG is greater than a second TAG identifier identifying a second tag and determining that a PL RS of a TCI state configured at the UE for the first UL transmission is one of an SSB of a non-serving cell of the UE and a CSI-RS having a first scrambling identifier different from a second scrambling identifier used for a PCI of a serving cell of the UE.

[0097] Fig. 9A method 900 of a RAN according to an embodiment of the present invention is shown. The method 900 includes sending 902 to a UE a TAG list including multiple configurations for multiple TAGs, the multiple configurations including a first configuration for a first TAG and a second configuration for a second TAG, the first TAG can be used in the UL to communicate with a first TRP of the RAN using a frequency, and the second TAG can be used in the UL to communicate with a second TRP of the network using the frequency.

[0098] The method 900 also includes receiving 904 a first UL transmission from the UE at the first TRP.

[0099] The method 900 also includes receiving 906 a second UL transmission from the UE at a second TRP.

[0100] In some implementations of method 900, the first configuration for the first TAG includes a first time alignment timer for the first TAG. In some such implementations, the second configuration for the second TAG includes a second time alignment timer for the second TAG.

[0101] In some embodiments, method 900 also includes sending an indication to the UE that the first HARQ buffer of the UE and the second HARQ buffer of the UE are shared across the first TAG and the second TAG.

[0102] In some embodiments, the method 900 also includes sending a first TCI state configuration to the UE, the configuration identifying the first TAG as being associated with the first TCI state. In some such embodiments, the method 900 also includes sending a second TCI state configuration to the UE, the configuration identifying the second TAG as being associated with the second TCI state.

[0103] In some implementations of method 900, a first configuration for a first TAG identifies a first CORESET pool associated with the first TAG. In some such implementations, a second configuration for a second TAG identifies a second CORESET pool associated with the second TAG.

[0104] DL reference timing determination for two TAs for mTRP

[0105] Another issue that arises when using two TAs for UL mDCI mTRPs relates to the DL reference timing, which is used as the basis for applying any TA commands received from the network to UL transmissions from the UE to the corresponding TRP. For example, it may be necessary to define a way to determine the DL reference timing for UL transmissions towards (each or either of) the two TRPs.

[0106] According to various aspects, various alternatives may be considered to determine the DL reference timing for which the TA command for UL transmissions will be applied to the corresponding TRP. Fig.10 1000 is shown, which shows information corresponding to various alternatives for determining DL reference timing for TA commands according to embodiments herein. Fig.10 As seen, for example, the UE may be configured with eight active TCI states 1002 for UL transmission (e.g., which may be joint UL / DLTCI states and / or UL TCI states), which have been activated at the UE using a media access control control element (MAC-CE) TCI state activation command.

[0107] In the first alternative, the DL reference timing for which the appropriate TA value is applied is determined based on the reception time of the source RS associated with the TCI state used for UL transmission. Note that in the case where the source RS for the TCI state is a sounding reference signal (SRS), the path loss RS associated with the TCI state can be used to determine the DL reference timing.

[0108] Reference Fig.10 , it can be seen that each TCI state 1002 is associated with a different source RS. Accordingly, it can be understood that the UE maintains eight timing loops corresponding to potential UL transmissions for each of the eight TCI states 1002, wherein each timing is determined relative to one of the source RSs 1004 corresponding to the TCI state.

[0109] In a second alternative, the UE determines a first DL reference timing based on a first detection path (in terms of time) of a corresponding DL frame from a source RS group with an activated TCI state sent by a serving cell (e.g., a reception time of the earliest source RS in the source RS group of the serving cell). In addition, the UE determines a second DL reference timing based on a first detection path (in terms of time) of a corresponding DL frame from a source RS group (from a TCI state sent by a non-serving cell) (e.g., a reception time of the earliest source RS in the source RS group of the non-serving cell).

[0110] Therefore, assuming that TCI state 1002 of table 1000 is used, according to the second alternative, the UE recognizes that SSB#1, SSB#3, CSI-RS#2, and CSI-RS#5 (source RSs of TCI states #0-3) are reference signals of the serving cell 1006, and SSB#2, SSB#5, CSI-RS#3, and CSI-RS#8 (source RSs of TCI states #4-7) are reference signals of the non-serving cell 1008. Thereafter, a first DL reference timing is determined / maintained based on the earliest one (at the UE) among SSB#1, SSB#3, CSI-RS#2, and CSI-RS#5 that arrives first in time, and a TA command associated with the TRP of the serving cell is applied using the first DL reference timing. In addition, a second DL reference timing is determined / maintained based on the first one of SSB#2, SSB#5, CSI-RS#3 and CSI-RS#8 that arrives first in time (at the UE), and a TA command associated with the TRP of the non-serving cell is applied using the second DL reference timing.

[0111] For a relatively large number of active TCI states at the UE, maintaining an amount of DL timing that is (up to) the number of active TCI states may be relatively complex (from a UE implementation perspective), as described in connection with the first alternative. In contrast, this second alternative enables the UE to maintain DL reference timing on a per-cell basis, so for the same set of active TCI states at the UE, the upper limit on complexity may be lower compared to the first alternative (where the number of DL reference timing maintained is equal to (up to) the total number of active TCI states).

[0112] In a third alternative, the UE determines a first DL reference timing based on a first detection path (in terms of time) of a corresponding DL frame from a source RS group of an activated TCI state associated with a first coresetPoolIndex value (e.g., a reception time of a source RS that is first in time in a source RS group of an activated TCI state associated with a first value in the coresetPoolIndex value). In addition, the UE determines a second DL reference timing based on a first detection path (in terms of time) of a corresponding DL frame from a source RS group of an activated TCI state associated with a second coresetPoolIndex value (e.g., a reception time of a source RS that is first in time in a source RS group of an activated TCI state associated with another value in the coresetPoolIndex value). In such a case, a coresetPoolIndex value may be provided by RRC signaling for each TCI state configured at the UE. In some cases, the coresetPoolIndex value may be "0" or "1". In some cases, each of the TRPs may be associated with one or other of the coresetPoolIndex via a TAG configuration for the TAG that the UE is using to communicate with the TRP, the TAG configuration indicating a corresponding coresetPoolIndex value (as described elsewhere herein).

[0113] Accordingly, assuming that TCI state 1002 of Table 1000 is used and further referring to coresetPoolIndex value 1010 of Table 1000, according to the third alternative scheme, the UE recognizes that TCI state #0-3 is associated with coresetPoolIndex value "0", and SSB#1, SSB#3, CSI-RS#2 and CSI-RS#5 are the source RSs of TCI state #0-3. In addition, the UE recognizes that TCI state #4-7 is associated with coresetPoolIndex value "1", and SSB#2, SSB#5, CSI-RS#3 and CSI-RS#8 are the source RSs of TCI state #4-7. Thereafter, the first DL reference timing is determined / maintained based on the first one of SSB#1, SSB#3, CSI-RS#2 and CSI-RS#5 that arrives first in time, and the TA command associated with the TRP corresponding to the coresetPoolIndex value "0" is applied using the first DL reference timing. In addition, a second DL reference timing is determined / maintained based on the first one of SSB#2, SSB#5, CSI-RS#3 and CSI-RS#8 that arrives first in time, and a TA command associated with the TRP corresponding to the coresetPoolIndex value "1" is applied using the second DL reference timing.

[0114] Please note that Figure 7 The specific arrangement of coresetPoolIndex values ​​for TCI states shown in is given by way of example and not by way of limitation. Other such arrangements are possible (including corresponding Figure 7 ). It is also contemplated that in Figure 7 In some alternative embodiments shown, different numbers (e.g., more than two) of coresetPoolIndex values ​​may be allocated across one or more configured / activated TCI states at the UE, in which case a corresponding number of TAGs (e.g., more than two TAGs) may each be associated with one or more TCI states in the set.

[0115] This third alternative enables the UE to maintain DL reference timing on a per coresetPoolIndex value basis, so for the same set of active TCI states at the UE, the upper bound on complexity can be lower compared to the first alternative (where the number of maintained DL reference timings is equal to (up to) the total number of active TCI states). In addition, since there is no assumption of using serving and non-serving cells, the third alternative can be used in the case of intra-cell mTRP usage.

[0116] In some embodiments (e.g., corresponding to the first to third alternatives), the UE may send a UE capability message to the network indicating whether the UE supports a maximum DL receive timing difference between a first DL reference timing for a first TRP and a second DL reference timing for a second TRP that is greater than a cyclic prefix (CP) length used by the UE. In the event that the difference between such first DL reference timing and second DL reference timing exceeds such CP length, the UE may stop using one or both of these DL reference timings.

[0117] Fig.11 A method 1100 of a UE according to an embodiment of the present invention is shown. The method 1100 includes identifying 1102 a first TCI state associated with a first source reference signal from one or more configured TCI states at the UE, the first TCI state for a first UL transmission made by the UE using a first TRP of a frequency to a network.

[0118] The method 1100 also includes identifying 1104 a second TCI state associated with a second source reference signal from one or more configured TCI states at the UE, the second TCI state for a second UL transmission made by the UE to a second TRP of the network using the frequency.

[0119] The method 1100 also includes determining 1106 a first DL reference timing corresponding to a first TRP based on a first reception time of a first source reference signal.

[0120] The method 1100 also includes determining 1108 a second DL reference timing corresponding to a second TRP based on a second reception time of a second source reference signal.

[0121] The method 1100 also includes performing 1110 a first UL transmission to a first TRP at a first time determined based on a first DL reference timing.

[0122] The method 1100 also includes performing 1112 a second UL transmission to a second TRP at a second time determined based on a second DL reference timing.

[0123] In some embodiments, method 1100 further includes sending a UE capability message to the network, the UE capability message indicating whether the UE supports using a DL reception timing difference between the first DL reference timing and the second DL reference timing that is greater than a CP length used by the UE.

[0124] In some implementations of method 1100, the first UL transmission and the second UL transmission are located on the same CC.

[0125] In some implementations of method 1100, the first UL transmission is located on a first CC and the second UL transmission is located on a second CC, wherein the first CC and the second CC are located on the frequency.

[0126] In some embodiments of method 1100, the first source reference signal comprises SSB.

[0127] In some implementations of method 1100, the first source reference signal includes a CSI-RS.

[0128] In some implementations of method 1100, the first source reference signal includes a PL RS for a first TCI state.

[0129] Fig.12 A method 1200 of a UE according to an embodiment of the present invention is shown. The method 1200 includes identifying 1202 a first one or more configured TCI states associated with a first one or more source reference signals of a serving cell having a first TRP of a network at the UE.

[0130] The method 1200 also includes identifying 1204 at the UE a second one or more configured TCI states associated with a second one or more source reference signals of a non-serving cell having a second TRP of the network.

[0131] The method 1200 also includes identifying 1206 a first source reference signal from the one or more source reference signals, the first source reference signal being a source reference signal of the first one or more source reference signals that is detected to arrive first in time at the UE during the DL frame.

[0132] The method 1200 also includes determining 1208 a first DL reference timing corresponding to the serving cell based on a first reception time of the first source reference signal.

[0133] The method 1200 also includes identifying 1210 a first UL transmission made by the UE on the serving cell using a frequency for a first TCI state from the first one or more configured TCI states.

[0134] The method 1200 also includes performing 1212 a first UL transmission on the serving cell at a first time determined based on the first DL reference timing.

[0135] In some embodiments, method 1200 also includes: identifying a second source reference signal from a second one or more source reference signals, the second source reference signal being the source reference signal among the second one or more source reference signals that is detected to arrive at the UE first in time during the DL frame; determining a second DL reference timing corresponding to the non-service cell based on a second reception time of the second source reference signal; identifying a second UL transmission made by the UE on the non-service cell using the frequency for the second TCI state from the second one or more configured TCI states; and performing a second UL transmission on the non-service cell at a second time determined based on the second DL reference timing.

[0136] In some embodiments, method 1200 also includes sending a UE capability message to the network, indicating whether the UE supports using a DL receive timing difference between a first DL reference timing and a second DL reference timing corresponding to a non-serving cell having a second TRP that is greater than a CP length used by the UE.

[0137] In some embodiments of method 1200, the first one or more source reference signals include SSB.

[0138] In some embodiments of method 1200, the first one or more source reference signals include a CSI-RS.

[0139] In some implementations of method 1200, the first one or more source reference signals include a PL RS for one of the first one or more configured TCI states.

[0140] Fig.13A method 1300 of a UE according to embodiments herein is shown. The method 1300 includes identifying 1302 a first one or more configured TCI states associated with a first CORESET pool corresponding to a first TRP of a network at the UE, the first one or more TCI states being associated with a first one or more source reference signals.

[0141] The method 1300 also includes identifying 1304 a second one or more configured TCI states at the UE associated with a second CORESET pool corresponding to a second TRP of the network, the second one or more TCI states being associated with second one or more source reference signals.

[0142] The method 1300 also includes identifying 1306 a first source reference signal from the one or more source reference signals, the first source reference signal being a source reference signal of the first one or more source reference signals that is detected to arrive first in time at the UE during the DL frame.

[0143] The method 1300 also includes determining 1308 a first DL reference timing corresponding to a first TRP based on a first reception time of a first source reference signal.

[0144] The method 1300 also includes identifying 1310 a first UL transmission made by the UE for a first TRP using a frequency in a first TCI state from a first one or more configured TCI states.

[0145] The method 1300 also includes performing 1312 a first UL transmission to a first TRP at a first time determined based on a first DL reference timing.

[0146] In some embodiments, method 1300 also includes: identifying a second source reference signal from a second one or more source reference signals, the second source reference signal being the source reference signal among the second one or more source reference signals that is detected to arrive at the UE first in time during the DL frame; determining a second DL reference timing corresponding to a second TRP based on a second reception time of the second source reference signal; identifying a second UL transmission of the second TRP made by the UE using the frequency using a second TCI state from the second one or more configured TCI states; and performing a second UL transmission to the second TRP at a second time determined based on the second DL reference timing.

[0147] In some implementations of method 1300, the first UL transmission and the second UL transmission are located on the same CC.

[0148] In some implementations of method 1300, the first UL transmission is located on a first CC and the second UL transmission is located on a second CC, wherein the first CC and the second CC are located on the frequency.

[0149] In some embodiments, method 1300 also includes sending a UE capability message to the network, indicating whether the UE supports using a DL receive timing difference between a first DL reference timing and a second DL reference timing corresponding to a second serving cell having a second TRP that is greater than a CP length used by the UE.

[0150] In some embodiments of method 1300, the first one or more source reference signals include SSB.

[0151] In some embodiments of method 1300, the first one or more source reference signals include a CSI-RS.

[0152] In some implementations of method 1300, the first one or more source reference signals include a PL RS for one of the first one or more configured TCI states.

[0153] Overlapping UL transmission using two TAs

[0154] Another issue that arises when using two TAs for UL mDCI mTRPs relates to the handling of overlap that may occur between UL transmissions in two adjacent time slots using different TAs toward different TRPs. This consideration may apply, for example, to situations where a wireless communication system includes one or more UEs that are not capable of simultaneous UL transmissions across a pair of UL antenna panels.

[0155] In such cases, the exact overlap length depends on the PUSCH time domain resource allocation (TDRA) value and N TA,offset Configuration. If a single N TA,offset is configured for and shared by two TRPs, the maximum overlap length for a 15 kHz subcarrier spacing (SCS) can be 32·16·64·T c =32768*T c ≈16us, which is greater than the CP length and 1 / 5 of an OFDM symbol. However, if separate N TA,offset value, then the maximum overlap length of two consecutive time slots can be (39936+63)·16·64*T c , which can be as high as several OFDM symbols.

[0156] Note that in the case where different TAs are used for different TRPs, due to the fact that independent schedulers may be used for the two TRPs and the fact that the BH may not be ideal (e.g., the BH characteristics applicable to the first TAG are not the same as the BH characteristics applicable to the second TAG), an overlap of the two time slots for the two panels in the described manner may occur regularly. Therefore, the defined way of handling such overlapping UL transmissions within the system improves system performance relative to this relatively common scenario.

[0157] Various methods may be considered to handle the situation where there is such an overlap between two UL transmissions associated with two TAs.

[0158] According to a first alternative, one or the other of these time slots adjusted by the corresponding TA for the corresponding TRP is used less relative to the normal time slots during the duration for the TRP to take into account the overlap. In other words, the data of the UL transmission on the UL panel corresponding to the TRP is discarded at the UE, which is for the overlapping part of the time slot used for the UL transmission (adjusted by the corresponding TA).

[0159] Fig.14A A diagram 1402 is shown showing a manner of discarding data of one UL transmission with respect to an overlap between time slots of two UL transmissions at different UL panels for a UE according to an embodiment of the present invention. As shown, the UE includes a first UL panel 1404 for performing a first UL transmission 1406 at a first time slot 1408 and a second UL panel 1410 for performing a second UL transmission 1412 at a second time slot 1414. In the case where the first UL panel 1404 and the first UL transmission 1406 are used for different TRPs, corresponding to the first UL transmission 1406 on the first UL panel 1404 and the second UL transmission 1412 on the second UL panel 1410, different TAs apply. Accordingly, there is an overlap 1416 between the end portion of the first time slot 1408 used by the first UL transmission 1406 on the first UL panel 1404 (adjusted by the applicable TA value for the first UL transmission 1406) and the beginning portion of the second time slot 1414 used for the second UL transmission 1412 on the second UL panel 1410 (adjusted by the applicable TA value for the second UL transmission 1412), thereby causing the first UL transmission 1406 to conflict with the second UL transmission 1412.

[0160] As shown in the figure, Fig.14A To resolve the conflict, the UE discards 1418 data of the second UL transmission 1412 for the beginning portion of the second time slot 1414 that overlaps with the first time slot 1408.

[0161] Fig. 14BA diagram 1420 showing a manner in which data of one UL transmission is discarded with respect to an overlap between time slots of two UL transmissions at different UL panels for a UE according to embodiments herein is shown. The first UL panel 1404, the first UL transmission 1406, the first time slot 1408, the second UL panel 1410, the second UL transmission 1412, the second time slot 1414, and the overlap 1416 may all be as described in connection with Fig.14A Arrange as described.

[0162] However, as shown in the figure, Fig.14A The situation is different. Fig. 14B To resolve the conflict, the UE discards 1422 data of the first UL transmission 1406 for the end portion of the first time slot 1408 that overlaps with the second time slot 1414.

[0163] Note that in some cases, parts with overlapping data are discarded from earlier time slots (e.g. Fig. 14B than discarding the part with overlapping data from the later time slot (such as in Fig.14A ) is more preferred because this results in the same result as at the beginning of the time slot (e.g., at the beginning of the second time slot 1414, as in Fig.14A In contrast, at the end of a time slot (e.g., at the end of the first time slot 1408, such as Fig. 14B This option may be used to preserve demodulation reference signal (DMRS) and / or uplink control information (UCI) symbols that may be present at the beginning of a UL transmission in a time slot (such as the beginning of a second UL transmission 1412 that may be present in the second time slot 1414).

[0164] In some cases, if the UE supports simultaneous transmission over multiple panels (STxMP) (and, for example, indicates this via a UE capability report), both time slots (e.g., the first time slot 1408 and the second time slot 1414) may be used without corresponding data reduction (even with overlap).

[0165] In some cases, UL transmissions associated with a serving cell may be prioritized over overlapping UL transmissions of non-serving cells. Fig.14A and Fig. 14B , which may mean, for example, that one of the first UL transmission 1406 and the second UL transmission 1412 has its data dropped 1418 / 1422 depending on which of these UL transmissions is for the UE's serving cell (not dropped) and which of these UL transmissions is for a non-serving cell (dropped). This may improve the reliability of the UE's connection to the network.

[0166] According to another alternative, signaling between the UE and the network may determine how to handle the first UL transmission and the second UL transmission when the end portion of the first time slot for the first UL transmission on the first second UL panel 1410 overlaps with the beginning portion of the second time slot for the second transmission on the second UL panel, as already described. This value may correspond to the difference between the end of the first time slot and the beginning of the second time slot. The UE measures the UL timing difference between the two applicable intra-frequency TAGs for the two TRPs and then reports this value to the network. This value may be measured / reported in units of OFDM symbols (e.g., the UE may report the number of symbols N to the network, where N ≥ 1).

[0167] In some such cases, based on the reported UL timing difference N, the network (eg, a base station of the network) may provide a contention handling indication to the UE indicating how to handle overlapping UL transmissions.

[0168] In the first example, the contention handling indication sent by the network to the UE indicates that the N starting symbols of the second time slot should not be used in the second UL panel. Accordingly, the UE discards the data of the second UL transmission for the N starting symbols of the second time slot.

[0169] In the second example, the contention handling indication sent by the network to the UE indicates that the N end symbols of the first time slot should not be used in the first UL panel. Accordingly, the UE discards the data of the first UL transmission for the N end symbols of the first time slot.

[0170] In a third example, the conflict handling indication sent by the network to the UE indicates that the first number K1 end symbols of the first time slot should not be used on the first UL panel, and the second number K2 start symbols of the second time slot should not be used on the second UL panel. In such a case, it can be K1+K2=N, where K1≥0 and K2≥0. Accordingly, the UE discards the data of the first UL transmission for the K1 end symbols of the first time slot, and also discards the data of the second UL transmission for the K2 start symbols of the second time slot.

[0171] In some cases, it may be that once the UE provides the network with the reported UL timing difference N, the UE is not expected by the network to transmit UL symbols within the overlapping N symbols on either the first time slot for the first UL panel or the second time slot for the second UL panel. In these cases, the transmission of the reported UL timing difference N accordingly imposes an effective restriction on the network / base station scheduler to avoid scheduling and / or not otherwise expect UL communications from the UE during such symbols.

[0172] Fig.15A method 1500 of a UE according to an embodiment of the present invention is shown. The method 1500 includes determining 1502 that an end portion of a first time slot for a first UL transmission on a first UL panel using a frequency for a first TRP (adjusted by a first TA for the first TRP) overlaps with a start portion of a second time slot for a second UL transmission on a second UL panel using the frequency for a second TRP (adjusted by a second TA for the second TRP).

[0173] The method 1500 also includes discarding 1504 one of: for the first UL transmission, first data for the end portion of the first time slot and overlapping with the second UL transmission; and for the second UL transmission, second data for the beginning portion of the second time slot and overlapping with the first UL transmission.

[0174] In some implementations of method 1500, the UE is not capable of implementing STxMP functionality.

[0175] In some embodiments, method 1500 also includes determining that the first UL transmission is for a serving cell and the second UL transmission is for a non-serving cell, wherein in response to determining that the first UL transmission is for a serving cell and the second UL transmission is for a non-serving cell, second data of the second UL transmission is discarded.

[0176] Fig.16 A method 1600 of a UE according to an embodiment of the present invention is shown. The method 1600 includes determining 1602 that an end portion of a first time slot for a first UL transmission on a first UL panel using a frequency for a first TRP (adjusted by a first TA for the first TRP) overlaps with a start portion of a second time slot for a second UL transmission on a second UL panel using the frequency for a second TRP (adjusted by a second TA for the second TRP).

[0177] The method 1600 also includes measuring 1604 a UL timing difference between a start of the first time slot and an end of the second time slot, wherein the UL timing difference is measured based on the number N of symbols.

[0178] The method 1600 also includes sending 1606 the UL timing difference to the network.

[0179] In some embodiments, method 1600 further includes receiving a contention handling indication from the network indicating that the N starting symbols of the second time slot should not be used on the second UL panel and discarding data of the second UL transmission for the N starting symbols of the second time slot.

[0180] In some embodiments, method 1600 also includes receiving a contention handling indication from the network indicating that the N end symbols of the first time slot should not be used on the first UL panel, and discarding data of the first UL transmission for the N end symbols of the first time slot.

[0181] In some embodiments, method 1600 also includes: receiving a conflict handling indication from the network, indicating that a first number K1 end symbols of a first time slot should not be used on a first UL panel, and a second number K2 start symbols of a second time slot should not be used on a second UL panel, where K1 plus K2 equals N; discarding first data of a first UL transmission for K1 end symbols of the first time slot; and discarding second data of a second UL transmission for K2 start symbols of the second time slot.

[0182] In some embodiments, the method 1600 further includes discarding first data of a first UL transmission for N ending symbols of a first time slot and discarding second data of a second UL transmission for N starting symbols of a second time slot.

[0183] Fig.17 A method 1700 of a RAN according to an embodiment of the present invention is shown. The method 1700 includes receiving 1702 from a UE a UL timing difference between an end of a first time slot for a first UL transmission of a first TRP of the RAN using a frequency on a first UL panel of the UE (adjusted by a first TA for the first TRP) and a start of a second time slot for a second UL transmission of a second TRP of the RAN using the frequency on a second UL panel of the UE (adjusted by a second TA for the second TRP), wherein the UL timing difference is indicated according to the number of symbols N.

[0184] Method 1700 also includes sending 1704 to the UE a conflict handling indication for use of one or more of: one or more of N end symbols of a first time slot on a first UL panel; and one or more of N start symbols of a second time slot on a second UL panel.

[0185] In some embodiments of the method 1700, the contention handling indication indicates to the UE that N end symbols of the first time slot on the first UL panel are not used.

[0186] In some embodiments of method 1700, the contention handling indication indicates to the UE that N starting symbols of the second time slot on the second UL panel are not used.

[0187] In some embodiments of method 1700, the conflict handling indication indicates to the UE not to use a first number K1 end symbols of a first time slot on a first UL panel and not to use a second number K2 start symbols of a second time slot on a second UL panel, where K1 plus K2 equals N.

[0188] Fig.18 A method 1800 of a RAN according to an embodiment of the present invention is shown. The method 1800 includes receiving 1802 from a UE an UL timing difference between an end of a first time slot for a first UL transmission of a first TRP of the RAN using a frequency on a first UL panel of the UE (adjusted by a first TA for the first TRP) and a start of a second time slot for a second UL transmission of a second TRP of the RAN using the frequency on a second UL panel of the UE (adjusted by a second TA for the second TRP), wherein the UL timing difference is indicated according to the number of symbols N.

[0189] The method 1800 also includes avoiding 1804 scheduling UL communications on each of the N ending symbols of the first time slot on the first UL panel and the N starting symbols of the second time slot on the second UL panel.

[0190] Fig.19 An exemplary architecture of a wireless communication system 1900 according to an embodiment disclosed herein is shown. The description provided below is for an exemplary wireless communication system 1900 operating in conjunction with the LTE system standard and / or the 5G or NR system standard provided in the 3GPP technical specifications.

[0191] like Fig.19 As shown, the wireless communication system 1900 includes UE 1902 and UE 1904 (although any number of UEs may be used). In this example, UE 1902 and UE 1904 are shown as smart phones (e.g., handheld touch screen mobile computing devices capable of connecting to one or more cellular networks), but may also include any mobile or non-mobile computing device configured for wireless communication.

[0192] UE 1902 and UE 1904 may be configured to be communicatively coupled to RAN 1906. In an embodiment, RAN 1906 may be NG-RAN, E-UTRAN, etc. UE 1902 and UE 1904 utilize connections (or channels) (shown as connection 1908 and connection 1910, respectively) with RAN 1906, where each connection (or channel) includes a physical communication interface. RAN 1906 may include one or more base stations, such as base station 1912 and base station 1914, to implement connection 1908 and connection 1910.

[0193] In this example, connection 1908 and connection 1910 are air interfaces to achieve such communication coupling and may conform to the RAT used by RAN 1906, such as LTE and / or NR.

[0194] In some embodiments, UE 1902 and UE 1904 may also directly exchange communication data via side link interface 1916. UE 1904 is shown as being configured to access an access point (shown as AP 1918) via connection 1920. By way of example, connection 1920 may include a local wireless connection, such as a connection conforming to any IEEE 802.11 protocol, wherein AP 1918 may include In this example, AP 1918 can connect to another network (eg, the Internet) without going through CN 1924.

[0195] In an embodiment, UE 1902 and UE 1904 may be configured to communicate with each other or with base station 1912 and / or base station 1914 over a multi-carrier communication channel using orthogonal frequency division multiplexing (OFDM) communication signals according to various communication techniques, such as but not limited to orthogonal frequency division multiple access (OFDMA) communication techniques (e.g., for downlink communication) or single carrier frequency division multiple access (SC-FDMA) communication techniques (e.g., for uplink and ProSe or sidelink communication), although the scope of the embodiment is not limited in this respect. OFDM signals may include multiple orthogonal subcarriers.

[0196] In some embodiments, all or part of base station 1912 or base station 1914 may be implemented as one or more software entities running on a server computer as part of a virtual network. In addition, or in other embodiments, base station 1912 or base station 1914 may be configured to communicate with each other via interface 1922. In an embodiment where wireless communication system 1900 is an LTE system (e.g., when CN 1924 is EPC), interface 1922 may be an X2 interface. The X2 interface may be defined between two or more base stations (e.g., two or more eNBs, etc.) connected to EPC and / or between two eNBs connected to EPC. In an embodiment where wireless communication system 1900 is an NR system (e.g., when CN 1924 is 5GC), interface 1922 may be an Xn interface. The Xn interface is defined between two or more base stations (e.g., two or more gNBs, etc.) connected to 5GC, between base station 1912 (e.g., gNB) and eNB connected to 5GC, and / or between two eNBs connected to 5GC (e.g., CN 1924).

[0197] RAN 1906 is shown as being communicatively coupled to CN 1924. CN 1924 may include one or more network elements 1926 configured to provide various data and telecommunication services to customers / subscribers (e.g., UE 1902 and users of UE 1904) connected to CN 1924 via RAN 1906. Components of CN 1924 may be implemented in one physical device or separate physical devices including components for reading and executing instructions from a machine-readable or computer-readable medium (e.g., a non-transitory machine-readable storage medium).

[0198] In an embodiment, CN 1924 may be an EPC, and RAN 1906 may be connected to CN 1924 via an S1 interface 1928. In an embodiment, S1 interface 1928 may be divided into two parts: an S1 user plane (S1-U) interface, which carries traffic data between base station 1912 or base station 1914 and a serving gateway (S-GW); and an S1-MME interface, which is a signaling interface between base station 1912 or base station 1914 and a mobility management entity (MME).

[0199] In an embodiment, CN 1924 may be a 5GC, and RAN 1906 may be connected to CN 1924 via an NG interface 1928. In an embodiment, NG interface 1928 may be divided into two parts: an NG user plane (NG-U) interface, which carries service data between base station 1912 or base station 1914 and a user plane function (UPF); and an S1 control plane (NG-C) interface, which is a signaling interface between base station 1912 or base station 1914 and an access and mobility management function (AMF).

[0200] Generally speaking, the application server 1930 may be an element that provides applications that use Internet Protocol (IP) bearer resources with the CN 1924 (e.g., packet-switched data services). The application server 1930 may also be configured to support one or more communication services (e.g., VoIP sessions, group communication sessions, etc.) for the UE 1902 and UE 1904 via the CN 1924. The application server 1930 may communicate with the CN 1924 via an IP communication interface 1932.

[0201] Fig. 20A system 2000 for performing signaling 2034 between a wireless device 2002 and a network device 2018 according to an embodiment disclosed herein is shown. The system 2000 can be part of a wireless communication system described herein. The wireless device 2002 can be, for example, a UE of a wireless communication system. The network device 2018 can be, for example, a base station (e.g., an eNB or a gNB) of a wireless communication system.

[0202] The wireless device 2002 may include one or more processors 2004. The processor 2004 may execute instructions to cause the wireless device 2002 to perform various operations as described herein. The processor 2004 may include one or more baseband processors implemented using, for example, a central processing unit (CPU), a digital signal processor (DSP), an application specific integrated circuit (ASIC), a controller, a field programmable gate array (FPGA) device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0203] The wireless device 2002 may include a memory 2006. The memory 2006 may be a non-transitory computer-readable storage medium storing instructions 2008 (these instructions may include, for example, instructions executed by the processor 2004). The instructions 2008 may also be referred to as program code or a computer program. The memory 2006 may also store data used by the processor 2004 and results calculated by the processor.

[0204] The wireless device 2002 may include one or more transceivers 2010, which may include a radio frequency (RF) transmitter and / or receiver circuit system, which uses an antenna 2012 of the wireless device 2002 to facilitate signaling (e.g., signaling 2034) transmitted or received by the wireless device 2002 to other devices (e.g., network device 2018) according to a corresponding RAT.

[0205] The wireless device 2002 may include one or more antennas 2012 (e.g., one, two, four or more). For implementations with multiple antennas 2012, the wireless device 2002 may take full advantage of the spatial diversity of such multiple antennas 2012 to send and / or receive multiple different data streams on the same time-frequency resources. This behavior may be referred to as (for example) MIMO behavior (referring to multiple antennas used at each of the transmitting device and the receiving device to implement this aspect). The MIMO transmission performed by the wireless device 2002 may be implemented based on precoding (or digital beamforming) applied to the wireless device 2002, and the wireless device multiplexes the data streams between the antennas 2012 based on known or assumed channel characteristics, so that each data stream is received with appropriate signal strength relative to other streams and at a desired position in the spatial domain (e.g., the position of the receiver associated with the data stream). Certain embodiments may use a single-user MIMO (SU-MIMO) approach (where data streams are all directed to a single receiver) and / or a multi-user MIMO (MU-MIMO) approach (where separate data streams may be directed to separate (different) receivers in different locations in the spatial domain).

[0206] In certain embodiments with multiple antennas, the wireless device 2002 may implement analog beamforming techniques whereby the phases of the signals transmitted by the antennas 2012 are relatively adjusted such that the (joint) transmissions of the antennas 2012 are directional (this is sometimes referred to as beam steering).

[0207] The wireless device 2002 may include one or more interfaces 2014. The interface 2014 may be used to provide input to the wireless device 2002 or provide output from the wireless device. For example, the wireless device 2002 as a UE may include an interface 2014, such as a microphone, a speaker, a touch screen, buttons, etc., to allow a user of the UE to input and / or output to the UE. Other interfaces of such UEs may be composed of transmitters, receivers, and other circuit systems that allow the UE to communicate with other devices (e.g., in addition to the transceiver 2010 / antenna 2012 described above), and may be based on known protocols (e.g., etc.) to perform the operation.

[0208] The wireless device 2002 may include an mTRP module 2016. The mTRP module 2016 may be implemented by hardware, software, or a combination thereof. For example, the mTRP module 2016 may be implemented as a processor, circuit, and / or instructions 2008 stored in the memory 2006 and executed by the processor 2004. In some examples, the mTRP module 2016 may be integrated within the processor 2004 and / or the transceiver 2010. For example, the mTRP module 2016 may be implemented by a combination of software components (e.g., executed by a DSP or a general purpose processor) and hardware components (e.g., logic gates and circuit systems) within the processor 2004 or the transceiver 2010.

[0209] The mTRP module 2016 can be used in various aspects of the present disclosure, for example, corresponding to Figures 1 to 18 mTRP module 2016 may be configured to, for example, perform TAG association for different UL transmissions for an mDCI mTRP, perform DL reference timing determination for two TAs for an mTRP, and / or handle overlapping UL transmissions employing two TAs, as described herein.

[0210] The network device 2018 may include one or more processors 2020. The processor 2020 may execute instructions to perform various operations of the network device 2018 as described herein. The processor 2020 may include one or more baseband processors implemented using, for example, a CPU, a DSP, an ASIC, a controller, an FPGA device, another hardware device, a firmware device, or any combination thereof configured to perform the operations described herein.

[0211] Network device 2018 may include memory 2022. Memory 2022 may be a non-transitory computer-readable storage medium storing instructions 2024 (these instructions may include, for example, instructions executed by processor 2020). Instructions 2024 may also be referred to as program code or a computer program. Memory 2022 may also store data used by processor 2020 and results calculated by the processor.

[0212] The network device 2018 may include one or more transceivers 2026, which may include RF transmitter and / or receiver circuitry that uses an antenna 2028 of the network device 2018 to facilitate signaling (e.g., signaling 2034) transmitted or received by the network device 2018 with other devices (e.g., wireless device 2002) according to a corresponding RAT.

[0213] The network device 2018 may include one or more antennas 2028 (e.g., one, two, four, or more). In an embodiment with multiple antennas 2028, the network device 2018 may perform MIMO, digital beamforming, analog beamforming, beam steering, etc. as described above.

[0214] The network device 2018 may include one or more interfaces 2030. The interface 2030 may be used to provide input to or output from the network device 2018. For example, the network device 2018 as a base station may include an interface 2030 composed of a transmitter, a receiver and other circuits (e.g., in addition to the transceiver 2026 / antenna 2028 described above), which enables the base station to communicate with other equipment in the core network and / or enables the base station to communicate with an external network, computer, database, etc., in order to achieve the purpose of operating, managing and maintaining the base station or other equipment operably connected to the base station.

[0215] The network device 2018 may include an mTRP module 2032. The mTRP module 2032 may be implemented by hardware, software, or a combination thereof. For example, the mTRP module 2032 may be implemented as a processor, circuit, and / or instructions 2024 stored in the memory 2022 and executed by the processor 2020. In some examples, the mTRP module 2032 may be integrated within the processor 2020 and / or the transceiver 2026. For example, the mTRP module 2032 may be implemented by a combination of software components (e.g., executed by a DSP or a general purpose processor) and hardware components (e.g., logic gates and circuit systems) within the processor 2020 or the transceiver 2026.

[0216] The mTRP module 2032 can be used in various aspects of the present disclosure, for example, corresponding to Figures 1 to 18 The mTRP module 2032 may be configured to, for example, perform network aspects of TAG association for different UL transmissions for an mDCI mTRP and / or perform network aspects related to handling overlapping UL transmissions employing two TAs, as described herein.

[0217] Embodiments contemplated herein include an apparatus including means for performing one or more elements of any of methods 800, 1100, 1200, 1300, 1500, and / or 1600. The apparatus may be, for example, an apparatus of a UE (such as wireless device 2002 as a UE, as described herein).

[0218] Embodiments contemplated herein include one or more non-transitory computer-readable media including instructions that, when executed by one or more processors of an electronic device, cause the electronic device to perform one or more elements of any of methods 800, 1100, 1200, 1300, 1500, and / or 1600. The non-transitory computer-readable medium may be, for example, a memory of a UE (such as memory 2006 of wireless device 2002 as a UE, as described herein).

[0219] Embodiments contemplated herein include an apparatus comprising logical components, modules, or circuitry for performing one or more elements of any of methods 800, 1100, 1200, 1300, 1500, and / or 1600. The apparatus may be, for example, an apparatus of a UE (such as wireless device 2002 as a UE, as described herein).

[0220] Embodiments contemplated herein include an apparatus comprising: one or more processors; and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of any of methods 800, 1100, 1200, 1300, 1500, and / or 1600. The apparatus may be, for example, an apparatus of a UE (such as wireless device 2002 as a UE, as described herein).

[0221] Embodiments contemplated herein include a signal as described in or associated with one or more elements of any of method 800 , method 1100 , method 1200 , method 1300 , method 1500 , and / or method 1600 .

[0222] Embodiments contemplated herein include a computer program or computer program product including instructions, wherein execution of the program by a processor causes the processor to perform one or more elements of any of methods 800, 1100, 1200, 1300, 1500, and / or 1600. The processor may be a processor of a UE (such as processor 2004 of wireless device 2002 as a UE, as described herein). These instructions may be located, for example, in a processor of a UE and / or on a memory (such as memory 2006 of wireless device 2002 as a UE, as described herein).

[0223] Embodiments contemplated herein include an apparatus including means for performing one or more elements of any of methods 900, 1700, and / or 1800. This apparatus may be, for example, an apparatus of a base station of a RAN (such as network device 2018 as a base station, as described herein).

[0224] Embodiments contemplated herein include one or more non-transitory computer-readable media including instructions that, when executed by one or more processors of an electronic device, cause the electronic device to perform one or more elements of any of methods 900, 1700, and / or 1800. This non-transitory computer-readable medium may be, for example, a memory of a base station of a RAN (such as memory 2022 of network device 2018 as a base station, as described herein).

[0225] Embodiments contemplated herein include an apparatus comprising logical components, modules, or circuit systems to perform one or more elements of any of methods 900, 1700, and / or 1800. This apparatus may be, for example, an apparatus of a base station of a RAN (such as network device 2018 as a base station, as described herein).

[0226] Embodiments contemplated herein include an apparatus comprising: one or more processors; and one or more computer-readable media comprising instructions that, when executed by the one or more processors, cause the one or more processors to perform one or more elements of any of methods 900, 1700, and / or 1800. This apparatus may be, for example, an apparatus of a base station of a RAN (such as network device 2018 as a base station, as described herein).

[0227] Embodiments contemplated herein include signals as described in or associated with one or more elements of any of method 900 , method 1700 , and / or method 1800 .

[0228] Embodiments contemplated herein include a computer program or computer program product including instructions, wherein execution of the program by a processing element causes the processing element to perform one or more elements of any of methods 900, 1700, and / or 1800. The processor may be a processor of a base station of the RAN (such as processor 2020 of network device 2018 as a base station, as described herein). These instructions may, for example, be located in a processor of a base station of the RAN and / or on a memory (such as memory 2022 of network device 2018 as a base station, as described herein).

[0229] For one or more embodiments, at least one of the components set forth in one or more of the foregoing figures may be configured to perform one or more operations, techniques, processes, and / or methods as described herein. For example, a baseband processor as described herein in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples set forth herein. For another example, a circuit system associated with a UE, a base station, a network element, etc. as described above in conjunction with one or more of the foregoing figures may be configured to operate according to one or more of the examples set forth herein.

[0230] Unless otherwise expressly stated, any of the above embodiments may be combined with any other embodiment (or combination of embodiments). The foregoing description of one or more specific implementations provides illustration and description, but is not intended to be exhaustive or to limit the scope of the embodiments to the precise form disclosed. In view of the above teachings, modifications and variations are possible or can be obtained from the practice of various embodiments.

[0231] Embodiments and implementations of the systems and methods described herein may include various operations that may be embodied in machine executable instructions to be executed by a computer system. A computer system may include one or more general or special purpose computers (or other electronic devices). A computer system may include hardware components that include specific logic components for performing operations; or may include a combination of hardware, software, and / or firmware.

[0232] It should be appreciated that the systems described herein include descriptions of specific embodiments. These embodiments may be combined into a single system, partially combined into other systems, separated into multiple systems, or otherwise divided or combined. In addition, it is contemplated that parameters, attributes, aspects, etc. of another embodiment may be used in one embodiment. For clarity, these parameters, attributes, aspects, etc. are described only in one or more embodiments, and it should be appreciated that these parameters, attributes, aspects, etc. may be combined with or substituted for parameters, attributes, aspects, etc. of another embodiment unless expressly stated herein.

[0233] It is understood that the use of personally identifiable information should be subject to privacy policies and practices that are generally recognized to meet or exceed industry or government requirements for maintaining user privacy. Specifically, personally identifiable information data should be managed and processed to minimize the risk of unintentional or unauthorized access or use, and the nature of the authorized use should be clearly stated to users.

[0234] Although the foregoing has been described in considerable detail for the sake of clarity, it will be apparent that certain changes and modifications may be made without departing from the principles of the invention. It should be noted that there are many alternative ways to implement both the processes and the apparatus described herein. Therefore, the embodiments of the present invention should be regarded as illustrative rather than restrictive, and the specification is not limited to the details given herein, but may be modified within the scope and equivalents of the appended claims.

Claims

1. A method of a user equipment (UE), the method comprising: receiving from a network a first configuration for a first timing advance group (TAG) used by the UE in an uplink (UL) to communicate with a first transmission reception point (TRP) of the network using a frequency and a second configuration for a second TAG used by the UE in an UL to communicate with a second TRP of the network using the frequency; identifying that a first UL transmission using the frequency is associated with the first TAG; as well as The first UL transmission is performed at a first time determined based on a first timing advance (TA) value for the first TAG.

2. The method according to claim 1, further comprising: identifying that a second UL transmission using the frequency is associated with the second TAG; as well as The second UL transmission is performed at a second time determined based on a second TA value for the second TAG. 3 . The method of claim 1 , wherein the first configuration for the first TAG and the second configuration for the second TAG are received in a TAG list including a plurality of configurations for a plurality of TAGs, the plurality of TAGs including the first TAG and the second TAG.

4. The method according to claim 3, further comprising: A UE capability message is sent to the network, where the UE capability message indicates a maximum number of the plurality of TAGs that can be supported at the UE.

5. The method according to claim 1, wherein: The first configuration for the first TAG includes a first time alignment timer value for the first TAG; and The second configuration for the second TAG includes a second time alignment timer value for the second TAG.

6. The method of claim 1 , wherein the first configuration for the first TAG comprises a first time alignment timer value for the first TAG, and wherein the method further comprises: A second time alignment timer value for the second TAG is determined to be equal to the first time alignment timer.

7. The method according to claim 1, further comprising: identifying that a first hybrid automatic repeat request (HARQ) buffer of the UE and a second HARQ buffer of the UE are shared across the first TAG and the second TAG; Determining that a first time alignment timer for the first TAG has timed out and a second time alignment timer for the second TAG has timed out; as well as In response to determining that the first time alignment timer for the first TAG has expired and the second time alignment timer for the second TAG has expired, each of the first HARQ buffer and the second HARQ buffer is flushed.

8. The method according to claim 1, further comprising: identifying that a first hybrid automatic repeat request (HARQ) buffer of the UE and a second HARQ buffer of the UE are not shared across the first TAG and the second TAG; Determining that a time alignment timer for the first TAG has timed out; as well as In response to determining that the time alignment timer for the first TAG has expired, the first HARQ buffer is flushed.

9. The method of claim 1 , wherein the identifying that the first UL transmission is associated with the first TAG comprises: Determining a TAG identifier of a transmission configuration indication (TCI) state configured at the UE for the first UL transmission identifies the first TAG.

10. The method of claim 1, wherein: The first configuration for the first TAG identifies a control resource set (CORESET) pool associated with the first TAG; and The identifying that the first UL transmission is associated with the first TAG includes determining that a downlink (DL) transmission scheduling the first UL transmission is received in a CORESET in the CORESET pool associated with the first TAG.

11. The method according to claim 1, wherein: The first UL transmission is a grant-free UL transmission; and The identifying that the first UL transmission is associated with the first TAG includes determining that a configuration for unlicensed UL transmission at the UE identifies a control resource set (CORESET) pool associated with the first TAG at the UE.

12. The method of claim 1, wherein: The first UL transmission is a grant-free UL transmission; and The identifying that the first UL transmission is associated with the first TAG includes determining that a configuration for unlicensed UL transmission at the UE identifies the first TAG.

13. The method of claim 1 , wherein the identifying that the first UL transmission is associated with the first TAG comprises: Determine that a first TAG identifier identifying the first TAG is greater than a second TAG identifier identifying the second TAG; and Determining a path loss (PL) reference signal of a transmission configuration indication (TCI) state configured at the UE for the first UL transmission is one of: a synchronization signal block (SSB) of a non-serving cell of the UE; and A channel state information reference signal (CSI-RS) having a scrambling identifier different from a physical cell identity (PCI) of a serving cell of the UE.

14. A method of a Radio Access Network (RAN), the method comprising: sending a timing advance group (TAG) list including a plurality of configurations for a plurality of TAGs to a user equipment (UE), the plurality of configurations including a first configuration for a first TAG and a second configuration for a second TAG, the first TAG being usable in an uplink (UL) to communicate with a first transmission reception point (TRP) of the RAN using a frequency, the second TAG being usable in the UL to communicate with a second TRP of the network using the frequency; receiving, at the first TRP, a first UL transmission from the UE; as well as A second UL transmission from the UE is received at the second TRP.

15. The method of claim 14, wherein the first configuration for the first TAG comprises a first time alignment timer value for the first TAG.

16. The method of claim 15, wherein the second configuration for the second TAG comprises a second time alignment timer value for the second TAG.

17. The method according to claim 15, further comprising: An indication is sent to the UE that a first hybrid automatic repeat request (HARQ) buffer of the UE and a second HARQ buffer of the UE are shared across the first TAG and the second TAG.

18. The method according to claim 15, further comprising: A first transmission configuration indication (TCI) state configuration identifying the first TAG is sent to the UE.

19. The method according to claim 18, further comprising: A second TCI state configuration identifying the second TAG is sent to the UE.

20. The method of claim 15, wherein the first configuration for the first TAG identifies a first control resource set (CORESET) pool associated with the first TAG.

21. The method of claim 20, wherein the second configuration for the second TAG identifies a second CORESET pool associated with the second TAG.

22. An apparatus comprising means for performing the method according to any one of claims 1 to 21.

23. A computer-readable medium comprising instructions, which, when executed by one or more processors of an electronic device, cause the electronic device to perform the method according to any one of claims 1 to 21.

24. An apparatus comprising logic components, modules or circuits for performing the method according to any one of claims 1 to 21.

Images