Acknowledgement codebook design for multiple transmit receive points

Abstract

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may receive a slot allocation to provide hybrid automatic repeat request (HARQ) acknowledgement (ACK) feedback to a plurality of transmit receive points (TRPs). For example, each TRP may be allocated at least one time slot for HARQ-ACK feedback, such that HARQ-ACK feedback for different TRP may not be transmitted in the same time slot. Additionally, the UE may determine a HARQ-ACK codebook that is TRP-specific for a feedback transmission to each TRP at a corresponding time slot. In some cases, the UE may also determine TRP-specific uplink parameters for feedback transmissions destined for each TRP. The UE may then transmit feedback to the TRP using a corresponding slot from the slot allocation and using the TRP-specific HARQ-ACK codebook and the TRP-specific uplink parameters.

Description

[0001] This divisional application is a divisional application of the PCT national phase patent application with a PCT international application date of September 18, 2019, national application number 201980060099.5, and titled "Design of confirmation codebook for multiple transmission and reception points". Technical Field

[0002] The following relates generally to wireless communications, and more particularly to an ACK codebook design for multiple transmit receive points (TRPs). Background Art

[0003] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, etc. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems), and fifth generation (5G) systems, which may be referred to as new radio (NR) systems. These systems may use various technologies, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform spread OFDM (DFT-S-OFDM). A wireless multiple access communication system may include several base stations or network access nodes, each of which simultaneously supports the communication of multiple communication devices, which may be referred to as user equipment (UE).

[0004] In some wireless communication systems, a UE may communicate with multiple base stations and / or multiple cells on one or more base stations simultaneously. Each base station or cell on a base station may be referred to as a TRP. In some cases, due to non-ideal backhaul connections between TRPs, the TRPs may be semi-statically coordinated for different downlink and uplink transmission configurations. Accordingly, due to the non-ideal backhaul connection, each TRP may transmit a separate downlink channel message to the UE, and the UE may receive these separate downlink channel messages at approximately the same time. The UE may then be expected to transmit ACK feedback for each downlink channel message received. However, the UE may not be able to transmit multiple uplink messages at the same time (e.g., simultaneously). Thus, an efficient technique for transmitting ACK feedback to the TRP for received downlink channel messages is desired. Summary of the invention

[0005] The described technology relates to improved methods, systems, devices and apparatuses that support the design of acknowledgment (ACK) codebooks for multiple transmit reception points (TRPs). In general, the described technology provides that a user equipment (UE) receives a time slot allocation for providing hybrid automatic repeat request (HARQ) ACK feedback to multiple TRPs. For example, each TRP may be allocated at least one time slot for HARQ-ACK feedback so that HARQ-ACK feedback for different TRPs may not be transmitted in the same time slot. Additionally, the UE may determine a TRP-specific HARQ-ACK codebook for feedback transmission to each TRP in the corresponding time slot, wherein the TRP-specific HARQ-ACK codebook is determined based on a downlink control information (DCI) message and / or a TRP-specific parameter. In some cases, the UE may also determine TRP-specific uplink parameters for feedback transmissions to each TRP, wherein the TRP-specific uplink parameters may include quasi-co-location (QCL) information, power control parameters, and timing advance (TA) parameters specific to each TRP. The UE may then transmit feedback to the TRP using a corresponding time slot from the time slot allocation and using a TRP-specific HARQ-ACK codebook and TRP-specific uplink parameters. Additionally, if multiple downlink channel transmissions have the same ending orthogonal frequency division multiplexing (OFDM) symbol, it may not be expected that the UE receives more than one downlink channel transmission from the same TRP in the same time slot or provides HARQ-ACK feedback for more than one downlink channel transmission in the same HARQ-ACK feedback transmission in the same time slot.

[0006] A method for wireless communication at a UE is described. The method may include: receiving a time slot allocation for the UE to provide HARQ-ACK feedback to a set of TRPs; determining a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation; determining one or more TRP-specific uplink parameters for feedback transmission to the TRP; and transmitting feedback to the TRP using a corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0007] An apparatus for wireless communication at a UE is described. The device may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions are executable by the processor so that the apparatus: receives a time slot allocation for the UE to provide HARQ-ACK feedback to a group of TRPs; determines a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the group of TRPs based on the time slot allocation; determines one or more TRP-specific uplink parameters for feedback transmission to the TRP; and transmits feedback to the TRP using a corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0008] Another apparatus for wireless communication at a UE is described. The apparatus may include means for receiving a time slot allocation for the UE to provide HARQ-ACK feedback to a set of TRPs; determining a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation; determining one or more TRP-specific uplink parameters for feedback transmission to the TRP; and transmitting feedback to the TRP using a corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0009] A non-transitory computer-readable medium storing code for wireless communication at a UE is described. The code may include instructions executable by a processor for the following operations: receiving a time slot allocation for the UE to provide HARQ-ACK feedback to a set of TRPs; determining a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation; determining one or more TRP-specific uplink parameters for feedback transmission to the TRP; and transmitting feedback to the TRP using a corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0010] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, receiving a time slot allocation may include operations, features, apparatus, or instructions for receiving an allocation of time slots to be used by a UE to provide HARQ-ACK feedback to different TRPs in a group of TRPs, wherein each time slot identified in the time slot allocation may be allocated for feedback transmission by the UE to only one TRP in the group of TRPs.

[0011] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, receiving a time slot allocation may include operations, features, apparatus, or instructions for receiving an allocation of time slots to be used by the UE to provide HARQ-ACK feedback to different TRPs in a group of TRPs, wherein the time slots may be allocated asymmetrically between the group of TRPs.

[0012] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining a HARQ-ACK codebook that varies depending on the TRP may include operations, features, means, or instructions for the following actions: receiving a DCI message including an indication of the size of the HARQ-ACK codebook.

[0013] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining a TRP-dependent HARQ-ACK codebook may include operations, features, apparatus, or instructions for the following actions: determining a TRP-dependent HARQ-ACK codebook based on at least one TRP-dependent parameter that can be received semi-statically.

[0014] In some examples of the methods, devices, and non-transitory computer-readable media described herein, at least one TRP-specific parameter may be one or more of: the number of cells for carrier aggregation (CA) supported by the TRP, a cell-specific uplink-downlink configuration associated with the cells of the TRP, a per-bandwidth part (BWP) table of time domain resource allocations for a physical downlink shared channel (PDSCH) for the TRP, a per-BWP parameter set defining PDSCH-to-feedback timing for the TRP, or a per-BWP PDSCH repetition factor for the TRP.

[0015] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for the following actions: identifying only one PDSCH reception opportunity from the TRP per time slot per cell for time domain resource allocations that overlap in time; and receiving one PDSCH transmission associated with the identified PDSCH reception opportunity from the TRP, wherein feedback to be transmitted in the corresponding time slot includes feedback information related to one PDSCH reception or PDSCH transmission.

[0016] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for: receiving an additional PDSCH from an additional TRP in a group of TRPs, the additional PDSCH having a time domain resource allocation that overlaps with the PDSCH received from the TRP in the same component carrier (CC); and transmitting HARQ-ACK feedback to the additional TRP in a time slot allocated for the additional TRP.

[0017] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining a TRP-specific HARQ-ACK codebook may include operations, features, apparatus, or instructions for comparing a time slot allocation with a cell-specific uplink-downlink configuration associated with a cell of the TRP, wherein the corresponding time slot may be used to transmit the feedback to the TRP only if the corresponding time slot can be identified as an uplink time slot by the cell-specific uplink-downlink configuration.

[0018] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining a TRP-specific HARQ-ACK codebook may include operations, features, apparatus, or instructions for comparing a time slot allocation with a cell-specific uplink-downlink configuration associated with the cell of the TRP, wherein the corresponding time slot may be used to transmit the feedback to the TRP only if the code elements allocated for feedback transmission in the corresponding time slot can also be allocated for uplink transmission by the cell-specific uplink-downlink configuration.

[0019] Some examples of the methods, apparatuses (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatuses, or instructions for transmitting additional information to the TRP using a corresponding time slot identified by a time slot allocation.

[0020] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the additional information may be in the form of a physical uplink shared channel (PUSCH) payload, a scheduling request (SR), or a channel state information (CSI) report, and wherein the feedback may be combined with the additional information on a single uplink channel.

[0021] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, using a corresponding time slot to transmit feedback to a TRP may include operations, features, apparatus, or instructions for the following actions: transmitting feedback via at least one of: via a physical uplink control channel (PUCCH), or via PUSCH as piggybacked uplink control information (UCI).

[0022] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, feedback transmitted to the TRP using the corresponding time slot includes feedback information related to only one PDSCH among multiple time domain resource allocations having the same ending OFDM codeword.

[0023] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining one or more TRP-specific uplink parameters for feedback transmission to a TRP may include operations, features, apparatus, or instructions for: identifying QCL information that can be configured for PUCCH transmission; and identifying TRP-specific QCL information for the TRP for the corresponding time slot.

[0024] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining one or more TRP-specific uplink parameters for a feedback transmission to a TRP may include operations, features, apparatus, or instructions for the following actions: identifying a TRP-specific power control parameter for a transmission to the TRP for a corresponding time slot.

[0025] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the TRP-dependent power control parameters may include at least one of an open-loop power control parameter and a closed-loop power control parameter.

[0026] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, determining one or more TRP-specific uplink parameters for a feedback transmission to a TRP may include operations, features, apparatus, or instructions for the following actions: identifying TRP-specific TA parameters for transmissions to the TRP for corresponding time slots.

[0027] In some examples of the methods, devices, and non-transitory computer-readable media described herein, receiving a timeslot allocation may include operations, features, means, or instructions for receiving a timeslot allocation via radio resource control (RRC) signaling.

[0028] Some examples of the methods, apparatus (devices) and non-transitory computer-readable media described herein may further include operations, features, apparatuses or instructions for the following actions: determining that a set of HARQ acknowledgment feedback messages are to be transmitted to a TRP in a set of TRPs; identifying a set of time slots in which the set of HARQ acknowledgment feedback messages are to be transmitted to the TRP based on time slot allocation; and transmitting the set of HARQ acknowledgment feedback messages to the TRP in the identified set of time slots.

[0029] A method of wireless communication at a TRP is described. The method may include: identifying, at the TRP, a timeslot assignment for at least one timeslot to be used by a UE to provide HARQ-ACK feedback to the TRP; transmitting a downlink message to the UE; transmitting an indication that the UE will use the at least one timeslot identified by the timeslot assignment to provide HARQ-ACK feedback; and receiving HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot assignment.

[0030] An apparatus for wireless communication at a TRP is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions are executable by the processor to cause the apparatus to: identify, at the TRP, a timeslot assignment for at least one timeslot to be used by a UE to provide HARQ-ACK feedback to the TRP; transmit a downlink message to the UE; transmit an indication that the UE will use the at least one timeslot identified by the timeslot assignment to provide HARQ-ACK feedback; and receive HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot assignment.

[0031] Another apparatus for wireless communication at a TRP is described. The apparatus may include means for: identifying, at the TRP, a timeslot assignment for at least one timeslot to be used by a UE to provide HARQ-ACK feedback to the TRP; transmitting an indication that the UE will use the at least one timeslot identified by the timeslot assignment to provide HARQ-ACK feedback; and receiving HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot assignment.

[0032] A non-transitory computer-readable medium storing code for wireless communication at a TRP is described. The code may include instructions executable by a processor for the following operations: identifying a time slot assignment for at least one time slot to be used by a UE to provide HARQ-ACK feedback to the TRP at the TRP; transmitting a downlink message to the UE; transmitting an indication that the UE will use the at least one time slot identified by the time slot assignment to provide HARQ-ACK feedback; and receiving HARQ-ACK feedback related to the downlink message from the UE on the at least one time slot identified by the time slot assignment.

[0033] Some examples of the methods, apparatus (devices) and non-transitory computer-readable media described herein may further include operations, features, apparatus or instructions for the following actions: transmitting the time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the TRP and the one or more other TRPs; receiving from the one or more other TRPs an additional time slot allocation identifying time slots to be used by the UE to provide HARQ-ACK feedback to the one or more other TRPs, wherein each time slot identified in the time slot allocation and the additional time slot allocation can be allocated for feedback transmission by the UE to only one TRP; or a combination thereof.

[0034] In some examples of the methods, devices, and non-transitory computer-readable media described herein, time slots may be allocated asymmetrically between the TRP and the additional TRPs.

[0035] In some examples of the methods, devices, and non-transitory computer-readable media described herein, transmitting the indication may include operations, features, means, or instructions for transmitting the indication via a DCI message.

[0036] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for transmitting a DCI message including an indication of the size of the HARQ-ACK codebook to be used by the UE when providing feedback to the TRP.

[0037] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for transmitting at least one semi-static TRP-specific parameter to the UE.

[0038] In some examples of the methods, devices, and non-transitory computer-readable media described herein, at least one TRP-specific parameter may be one or more of: the number of cells for CA supported by the TRP, a cell-specific uplink-downlink configuration associated with the cells of the TRP, a per-BWP table of time domain resource allocations for the PDSCH for the TRP, a per-BWP parameter set defining PDSCH to feedback timing for the TRP, or a per-BWP PDSCH repetition factor for the TRP.

[0039] In some examples of the methods, devices, and non-transitory computer-readable media described herein, receiving HARQ-ACK feedback related to a downlink message may include operations, features, devices, or instructions for receiving HARQ-ACK feedback on at least one time slot identified by a time slot allocation only if the at least one time slot is identified as an uplink time slot by a cell-specific uplink-downlink configuration associated with a TRP.

[0040] In some examples of the methods, devices, and non-transitory computer-readable media described herein, receiving HARQ-ACK feedback related to a downlink message may include operations, features, devices, or instructions for receiving HARQ-ACK feedback on a codeword of at least one time slot identified by a time slot allocation only if the codeword of at least one time slot can be allocated for uplink transmission by a cell-specific uplink-downlink configuration associated with a TRP.

[0041] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for receiving additional information from the UE using at least one time slot identified by the time slot assignment.

[0042] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, the additional information may be in the form of: PUSCH payload, SR, or CSI report, and wherein the HARQ-ACK feedback may be combined with the additional information on a single uplink channel.

[0043] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, receiving HARQ-ACK feedback related to a downlink message may include operations, features, apparatus, or instructions for the following actions: receiving HARQ-ACK feedback via at least one of the following: via PUCCH, or via PUSCH as piggybacked UCI.

[0044] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, transmitting a downlink message to a UE may include operations, features, apparatus, or instructions for the following actions: transmitting only one PDSCH from a TRP per time slot with time domain resource allocation having the same ending OFDM codeword.

[0045] In some examples of the methods, devices (apparatus), and non-transitory computer-readable media described herein, HARQ-ACK feedback received from a UE in at least one time slot includes feedback information related to only one PDSCH in multiple time-domain resource allocations having the same ending OFDM codeword.

[0046] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for the following actions: transmitting QCL information that varies depending on the TRP to the UE.

[0047] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for transmitting to a UE TRP-specific power control parameters for transmissions to the TRP during at least one time slot.

[0048] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, apparatus, or instructions for transmitting to a UE TRP-specific TA parameters for transmissions to the TRP during at least one time slot.

[0049] Some examples of the methods, apparatus (devices), and non-transitory computer-readable media described herein may further include operations, features, means, or instructions for transmitting the time slot allocation via RRC signaling. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 An example of a wireless communication system supporting an acknowledgment (ACK) codebook design for multiple transmit reception points (TRPs) in accordance with various aspects of the present disclosure is illustrated.

[0051] Figure 2 An example of a wireless communication system supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is illustrated.

[0052] Figure 3 An example of time slot allocation supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is illustrated.

[0053] Figure 4An example of downlink channel scheduling that supports ACK codebook design for multiple TRPs according to various aspects of the present disclosure is illustrated.

[0054] Figure 5 An example of uplink channel repetition configuration supporting ACK codebook design for multiple TRPs in accordance with various aspects of the present disclosure is illustrated.

[0055] Figure 6 An example of a process flow supporting ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is illustrated.

[0056] Figure 7 and 8 A block diagram of a device supporting an ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown.

[0057] Fig. 9 A block diagram of a UE codebook manager supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown.

[0058] Fig.10 A diagram of a system including devices supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown.

[0059] Fig.11 and 12 A block diagram of a device supporting an ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown.

[0060] Fig.13 A block diagram of a TRP slot allocation manager supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure is shown.

[0061] Fig.14 A diagram of a system including devices supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown.

[0062] Figures 15 to 20 A flow chart illustrating a method for supporting ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0063] In some wireless communication systems, multiple transmit-receive points (TRPs) may communicate with the same user equipment (UE) in a non-coherent manner (e.g., non-coherent joint transmission (NCTJ)) at the same or different times. For example, multiple TRPs may be able to transmit physical downlink control channel (PDCCH) and / or physical downlink shared channel (PDSCH) messages to the UE (based on radio resource control (RRC) configuration). Additionally, due to non-ideal backhaul connections between TRPs (e.g., increased latency on the backhaul connection), multiple TRPs may be semi-statically coordinated with respect to different downlink channels, uplink channels, and reference signal (RS) configurations. Based on the non-ideal backhaul connection, multiple TRPs may not be able to coordinate quickly enough, and as such, separate PDCCH and PDSCH transmissions may be sent, where the UE may be expected to transmit HARQ-ACK feedback for each downlink transmission based on a hybrid automatic repeat request (HARQ) acknowledgment (ACK) codebook. However, although the UE can receive multiple downlink transmissions simultaneously, the UE may not be able to transmit multiple uplink ACK feedback messages simultaneously.

[0064] To alleviate the need to transmit multiple uplink ACK feedback messages simultaneously, the scheduling TRP (e.g., base station, network, Gigabit B node (gNB), etc.) may configure the UE with a timeslot allocation for physical uplink control channel (PUCCH) feedback per TRP. For example, a first timeslot may be allocated for ACK feedback in the PUCCH to the first TRP, a second timeslot may be allocated for ACK feedback in the PUCCH to the second TRP, and so on. Accordingly, ACK / negative ACK (NACK) to different TRPs may not be transmitted in the same timeslot. The timeslot allocation may be explicitly indicated to the UE by scheduling the TRP so that the UE knows which timeslot corresponds to which TRP and transmits ACK / NACK feedback based on the timeslot / TRP configuration. Additionally, the UE may determine different HARQ-ACK codebooks for each timeslot / TRP based on each TRP having different parameters for codebook determination. In some cases, the UE may semi-statically determine the HARQ-ACK codebook for each TRP and use the corresponding HARQ-ACK codebook for the corresponding TRP in each timeslot. Additionally or alternatively, the HARQ-ACK codebook may be dynamically indicated by a scheduling TRP, wherein the scheduling TRP indicates information that enables the UE to construct the HARQ-ACK codebook in each ACK feedback transmission. In some cases, quasi-colocation (QCL), power control, and timing advance (TA) may also be specific to each time slot / TRP.

[0065] Certain aspects of the subject matter described herein may be implemented to achieve one or more advantages. The described techniques may support improvements in, among other advantages, transmitting ACK feedback to a TRP for received downlink channel messages, reducing signaling overhead, and improving reliability. Thus, the supported techniques may include improved network operation, and in some examples, may improve the efficiency of the network, among other benefits.

[0066] Various aspects of the present disclosure are initially described in the context of a wireless communication system. Additional wireless communication systems, time slot allocations, downlink channel scheduling, uplink channel repetition configurations, and process flows are subsequently provided to illustrate various aspects of the present disclosure. Various aspects of the present disclosure are further illustrated and described by and with reference to apparatus diagrams, system diagrams, and flow charts related to ACK codebook designs for multiple TRPs.

[0067] Figure 1 An example of a wireless communication system 100 supporting an ACK codebook design for multiple TRPs in accordance with various aspects of the present disclosure is illustrated. The wireless communication system 100 includes a base station 105, a UE 115, and a core network 130. In some examples, the wireless communication system 100 may be a long term evolution (LTE) network, an advanced LTE (LTE-A) network, an LTE-A Pro network, or a new radio (NR) network. In some cases, the wireless communication system 100 may support enhanced broadband communications, ultra-reliable (e.g., mission-critical) communications, low latency communications, or communications with low-cost and low-complexity devices.

[0068] The base station 105 may communicate wirelessly with the UE 115 via one or more base station antennas. The base station 105 described herein may include or may be referred to by those skilled in the art as a base transceiver station, a radio base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next generation Node B, or a Gigabit Node B (any of which may be referred to as a gNB), a home Node B, a home evolved Node B, or some other suitable terminology. The wireless communication system 100 may include different types of base stations 105 (e.g., macro cell base stations or small cell base stations). The UE 115 described herein may be able to communicate with various types of base stations 105 and network equipment (including macro eNBs, small cell eNBs, gNBs, relay base stations, etc.).

[0069] Each base station 105 may be associated with a particular geographic coverage area 110 in which it supports communications with various UEs 115. Each base station 105 may provide communications coverage for the respective geographic coverage area 110 via a communications link 125, and the communications link 125 between the base station 105 and the UE 115 may utilize one or more carriers. The communications link 125 shown in the wireless communication system 100 may include an uplink transmission from the UE 115 to the base station 105, or a downlink transmission from the base station 105 to the UE 115. Downlink transmissions may also be referred to as forward link transmissions, and uplink transmissions may also be referred to as reverse link transmissions.

[0070] The geographic coverage area 110 of the base station 105 may be divided into sectors that constitute only a portion of the geographic coverage area 110, and each sector may be associated with a cell. For example, each base station 105 may provide communication coverage for a macrocell, a small cell, a hotspot, or other types of cells, or various combinations thereof. In some examples, the base station 105 may be mobile and therefore provide communication coverage for a mobile geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies may overlap, and overlapping geographic coverage areas 110 associated with different technologies may be supported by the same base station 105 or different base stations 105. The wireless communication system 100 may include, for example, a heterogeneous LTE / LTE-A / LTE-A Pro or NR network, in which different types of base stations 105 provide coverage for various geographic coverage areas 110.

[0071] The term "cell" refers to a logical communication entity for communicating with base station 105 (e.g., on a carrier), and may be associated with an identifier to distinguish adjacent cells operating via the same or different carriers (e.g., physical cell identifier (PCID), virtual cell identifier (VCID)). In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types that may provide access to different types of devices (e.g., machine type communication (MTC), narrowband Internet of Things (NB-IoT), enhanced mobile broadband (eMBB), or others). In some cases, the term "cell" may refer to a portion of a geographic coverage area 110 (e.g., a sector) on which the logical entity operates.

[0072] Each UE 115 can be dispersed throughout the wireless communication system 100, and each UE 115 can be stationary or mobile. UE 115 can also be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable term, wherein "device" can also be referred to as a unit, a station, a terminal, or a client. UE 115 can be a personal electronic device, such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, UE 115 can also refer to a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or an MTC device, etc., which can be implemented in various items (such as electrical appliances, vehicles, meters, etc.).

[0073] Some UEs 115, such as MTC or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC may refer to data communication technology that allows devices to communicate with each other or with a base station 105 without human intervention. In some examples, M2M communication or MTC may include communications from devices that integrate sensors or meters to measure or capture information and relay the information to a central server or application, which may utilize the information or present the information to a person interacting with the program or application. Some UEs 115 may be designed to collect information or implement automated behavior of machines. Examples of applications for MTC devices include: smart metering, inventory monitoring, water level monitoring, equipment monitoring, health care monitoring, field survival monitoring, weather and geographic event monitoring, queue management and tracking, remote security sensing, physical access control, and transaction-based commercial charging.

[0074] Some UEs 115 may be configured to employ a reduced power consumption mode of operation, such as half-duplex communication (e.g., a mode that supports unidirectional communication via transmission or reception but not simultaneous transmission and reception). In some examples, half-duplex communication may be performed with a reduced peak rate. Other power saving techniques for UE 115 include entering a power saving "deep sleep" mode when not engaged in active communications, or operating over a limited bandwidth (e.g., in accordance with narrowband communications). In some cases, UE 115 may be designed to support critical functions (e.g., mission critical functions), and the wireless communication system 100 may be configured to provide ultra-reliable communications for these functions.

[0075] In some cases, UE 115 may also be able to communicate directly with other UE 115 (e.g., using a peer-to-peer (P2P) or device-to-device (D2D) protocol). One or more UEs in a group of UEs 115 utilizing D2D communication may be within the geographic coverage area 110 of the base station 105. Other UEs 115 in this group may be outside the geographic coverage area 110 of the base station 105, or otherwise unable to receive transmissions from the base station 105. In some cases, each group of UEs 115 communicating via D2D communication may utilize a one-to-many (1:M) system, in which each UE 115 transmits to each other UE 115 in the group. In some cases, the base station 105 facilitates the scheduling of resources for D2D communication. In other cases, D2D communication is performed between UEs 115 without involving the base station 105.

[0076] The base stations 105 may communicate with the core network 130 and with each other. For example, the base stations 105 may interface with the core network 130 via a backhaul link 132 (e.g., via S1, N2, N3, or other interfaces). The base stations 105 may communicate with each other directly (e.g., directly between the base stations 105) or indirectly (e.g., via the core network 130) on a backhaul link 134 (e.g., via X2, Xn, or other interfaces).

[0077] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 may be an evolved packet core (EPC), which may include at least one mobility management entity (MME), at least one serving gateway (S-GW), and at least one packet data network (PDN) gateway (P-GW). The MME may manage non-access layer (e.g., control plane) functions such as mobility, authentication, and bearer management of UEs 115 served by base stations 105 associated with the EPC. User IP packets may be delivered through the S-GW, which itself may be connected to the P-GW. The P-GW may provide IP address allocation and other functions. The P-GW may be connected to network operator IP services. Operator IP services may include access to the Internet, intranets, IP multimedia subsystems (IMS), or packet switched (PS) streaming services.

[0078] At least some network devices (such as base stations 105) may include subcomponents, such as access network entities, which may be examples of access node controllers (ANCs). Each access network entity may communicate with each UE 115 through several other access network transport entities, which may be referred to as radio heads, smart radio heads, or TRPs. In some configurations, the various functions of each access network entity or base station 105 may be distributed across various network devices (e.g., radio heads and access network controllers) or merged into a single network device (e.g., base station 105). Additionally or alternatively, a base station 105 as described herein may be referred to as a TRP 105.

[0079] The wireless communication system 100 may operate using one or more frequency bands, typically in the range of 300 MHz to 300 GHz. In general, the 300 MHz to 3 GHz region is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from about 1 decimeter to 1 meter long. UHF waves may be blocked or redirected by buildings and environmental features. However, these waves may penetrate various structures sufficiently for macro cells to provide services to UEs 115 located indoors. Transmission of UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 km) compared to transmission using lower frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

[0080] The wireless communication system 100 may also operate in the Super High Frequency (SHF) region using a frequency band from 3 GHz to 30 GHz, also known as the centimeter band. The SHF region includes frequency bands that may be opportunistically used by devices that can tolerate interference from other users, such as the 5 GHz Industrial, Scientific, and Medical (ISM) band.

[0081] The wireless communication system 100 may also operate in the extremely high frequency (EHF) division of the spectrum (e.g., from 30 GHz to 300 GHz), which is also referred to as the millimeter band. In some examples, the wireless communication system 100 may support millimeter wave (mmW) communications between the UE 115 and the base station 105, and the EHF antenna of the corresponding device may be even smaller and more closely spaced than the UHF antenna. In some cases, this may facilitate the use of antenna arrays within the UE 115. However, the propagation of EHF transmissions may be subject to even greater atmospheric attenuation and shorter range than SHF or UHF transmissions. The technology disclosed herein may be adopted across transmissions using one or more different frequency divisions, and the use of designated frequency bands across these frequency divisions may differ by country or regulatory agency.

[0082] In some cases, the wireless communication system 100 may utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communication system 100 may adopt license assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed band (such as a 5GHz ISM band). When operating in an unlicensed radio frequency spectrum band, wireless devices (such as base stations 105 and UE 115) may adopt a listen-before-talk (LBT) procedure to ensure that the frequency channel is clear before transmitting data. In some cases, operations in unlicensed bands may be based on CA configurations (e.g., LAA) in coordination with CCs operating in licensed bands. Operations in unlicensed spectrum may include downlink transmissions, uplink transmissions, peer-to-peer transmissions, or a combination of these. Duplexing in unlicensed spectrum may be based on frequency division duplexing (FDD), time division duplexing (TDD), or a combination of the two.

[0083] In some examples, the base station 105 or the UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communication, or beamforming. For example, the wireless communication system 100 may use a transmission scheme between a transmitting device (e.g., the base station 105) and a receiving device (e.g., the UE 115), wherein the transmitting device is equipped with multiple antennas and the receiving device is equipped with one or more antennas. MIMO communication may employ multipath signal propagation to increase spectral efficiency by transmitting or receiving multiple signals via different spatial layers, which may be referred to as spatial multiplexing. For example, the transmitting device may transmit multiple signals via different antennas or different antenna combinations. Similarly, the receiving device may receive multiple signals via different antennas or different antenna combinations. Each of these multiple signals may be referred to as a separate spatial stream and may carry bits associated with the same data stream (e.g., the same codeword) or different data streams. Different spatial layers may be associated with different antenna ports for channel measurement and reporting. MIMO technology includes single-user MIMO (SU-MIMO), in which multiple spatial layers are transmitted to the same receiving device, and multi-user MIMO (MU-MIMO), in which multiple spatial layers are transmitted to multiple devices.

[0084] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a base station 105 or a UE 115) to shape or direct an antenna beam (e.g., a transmit beam or a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals communicated via antenna elements of an antenna array so that signals propagating at a particular orientation relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals communicated via antenna elements may include the transmitting device or the receiving device applying a particular amplitude and phase shift to the signal carried via each antenna element associated with the device. Adjustments associated with each antenna element may be defined by a set of beamforming weights associated with a particular orientation (e.g., relative to the antenna array of the transmitting device or the receiving device, or relative to some other orientation).

[0085] In one example, the base station 105 may use multiple antennas or antenna arrays to perform beamforming operations for directional communication with the UE 115. For example, some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be transmitted multiple times by the base station 105 in different directions, which may include a signal being transmitted according to different beamforming weight sets associated with different transmission directions. Transmissions in different beam directions may be used to identify (e.g., by the base station 105 or a receiving device, such as the UE 115) a beam direction for subsequent transmission and / or reception by the base station 105. Some signals (such as data signals associated with a particular receiving device) may be transmitted by the base station 105 in a single beam direction (e.g., a direction associated with a receiving device (such as the UE 115)). In some examples, the beam direction associated with transmissions along a single beam direction may be determined based at least in part on signals transmitted in different beam directions. For example, UE 115 may receive one or more signals transmitted by base station 105 in different directions, and UE 115 may report indications of the signals it received with the highest signal quality or other acceptable signal quality to base station 105. Although these techniques are described with reference to signals transmitted by base station 105 in one or more directions, UE 115 may use similar techniques for transmitting signals multiple times in different directions (e.g., for identifying a beam direction for subsequent transmission or reception by UE 115) or for transmitting signals in a single direction (e.g., for transmitting data to a recipient device).

[0086] A receiving device (e.g., UE 115, which may be an example of a mmW receiving device) may try multiple receive beams when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from base station 105. For example, the receiving device may try multiple receive directions by receiving via different antenna subarrays, processing received signals according to different antenna subarrays, receiving according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, or processing received signals according to different receive beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as "listening" according to different receive beams or receive directions. In some examples, the receiving device may use a single receive beam to receive along a single beam direction (e.g., when receiving a data signal). The single receive beam may be aligned on a beam direction determined at least in part based on listening according to different receive beam directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio, or other acceptable signal quality based at least in part on listening according to multiple beam directions).

[0087] In some cases, the antennas of a base station 105 or a UE 115 may be located within one or more antenna arrays that may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some cases, the antennas or antenna arrays associated with a base station 105 may be located at different geographic locations. A base station 105 may have an antenna array having several rows and columns of antenna ports that the base station 105 may use to support beamforming for communications with a UE 115. Likewise, a UE 115 may have one or more antenna arrays that may support various MIMO or beamforming operations.

[0088] In some cases, the wireless communication system 100 can be a packet-based network that operates according to a layered protocol stack. In the user plane, the communication of the bearer or packet data convergence protocol (PDCP) layer can be based on IP. In some cases, the radio link control (RLC) layer can perform packet segmentation and reorganization to communicate on the logical channel. The media access control (MAC) layer can perform priority handling and multiplex logical channels into transport channels. The MAC layer can also use HARQ to provide retransmission of the MAC layer, thereby improving link efficiency. In the control plane, the RRC protocol layer can provide the establishment, configuration and maintenance of the RRC connection of the radio bearer that supports user plane data between the UE 115 and the base station 105 or the core network 130. In the physical (PHY) layer, the transport channel can be mapped to the physical channel.

[0089] In some cases, UE 115 and base station 105 may support retransmission of data to increase the likelihood that the data is successfully received. HARQ feedback is a technique that increases the likelihood of correctly receiving data on communication link 125. HARQ may include a combination of error detection (e.g., using cyclic redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ can improve the throughput of the MAC layer in poor radio conditions (e.g., signal-to-noise ratio conditions). In some cases, a wireless device may support simultaneous slot HARQ feedback, where the device may provide HARQ feedback in a specific time slot for data received in a previous symbol in the time slot. In other cases, the device may provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0090] The time interval in LTE or NR can be represented by a basic time unit (which may refer to a sampling period T for example). s =1 / 30,720,000 seconds). The time intervals of the communication resources may be organized according to radio frames each having a duration of 10 milliseconds (ms), where the frame period may be expressed as T f =307,200T s . A radio frame may be identified by a system frame number (SFN) ranging from 0 to 1023. Each frame may include 10 subframes numbered from 0 to 9, and each subframe may have a duration of 1 ms. A subframe may be further divided into 2 slots, each slot having a duration of 0.5 ms, and each slot may contain 6 or 7 modulation symbol periods (e.g., depending on the length of a cyclic prefix prepended to each symbol period). Excluding the cyclic prefix, each symbol period may contain 2048 sampling periods. In some cases, a subframe may be the minimum scheduling unit of the wireless communication system 100 and may be referred to as a transmission time interval (TTI). In other cases, the minimum scheduling unit of the wireless communication system 100 may be shorter than a subframe or may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI) or in a selected component carrier using sTTI).

[0091] In some wireless communication systems, a time slot may be further divided into a plurality of mini-slots containing one or more symbols. In some instances, a symbol of a mini-slot or a mini-slot may be the minimum scheduling unit. For example, each symbol may vary in duration depending on the subcarrier spacing or the operating frequency band. Further, some wireless communication systems may implement time slot aggregation, wherein a plurality of time slots or mini-slots are aggregated together and used for communication between UE 115 and base station 105.

[0092] The term "carrier" refers to a set of radio frequency spectrum resources having a defined physical layer structure for supporting communications on the communication link 125. For example, a carrier of the communication link 125 may include a portion of a radio frequency spectrum band that operates according to a physical layer channel for a given radio access technology. Each physical layer channel may carry user data, control information, or other signaling. A carrier may be associated with a predefined frequency channel (e.g., an E-UTRA Absolute Radio Frequency Channel Number (EARFCN)) and may be located according to a channel grid for discovery by a UE 115. A carrier may be downlink or uplink (e.g., in FDD mode), or configured to carry downlink communications and uplink communications (e.g., in TDD mode). In some examples, a signal waveform transmitted on a carrier may include multiple subcarriers (e.g., using a multi-carrier modulation (MCM) technique such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-s-OFDM)).

[0093] The organization structure of the carrier may be different for different radio access technologies (e.g., LTE, LTE-A, LTE-A Pro, NR, etc.). For example, communications on a carrier may be organized according to TTIs or time slots, each of which may include user data and control information or signaling to support decoding of the user data. A carrier may also include dedicated acquisition signaling (e.g., synchronization signals or system information, etc.) and control signaling to coordinate the operation of the carrier. In some examples (e.g., in a carrier aggregation configuration), a carrier may also have acquisition signaling or control signaling to coordinate the operation of other carriers.

[0094] Physical channels may be multiplexed on a carrier according to various techniques. Physical control channels and physical data channels may be multiplexed on a downlink carrier, for example, using a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique. In some examples, control information transmitted in a physical control channel may be distributed in a cascaded manner between different control regions (e.g., between a common control region or common search space and one or more UE-specific control regions or UE-specific search spaces).

[0095] A carrier may be associated with a particular bandwidth of the radio frequency spectrum, and in some examples, the carrier bandwidth may be referred to as the "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of several predetermined bandwidths of a carrier for a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 MHz). In some examples, each served UE 115 may be configured to operate on part or all of the carrier bandwidth. In other examples, some UEs 115 may be configured to operate using a narrowband protocol type associated with a predefined portion or range (e.g., a set of subcarriers or RBs) within a carrier (e.g., an "in-band" deployment of a narrowband protocol type).

[0096] In a system using MCM technology, a resource element may include a symbol period (e.g., the duration of a modulation symbol) and a subcarrier, where the symbol period and the subcarrier spacing are inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme). Thus, the more resource elements received by UE 115 and the higher the order of the modulation scheme, the higher the data rate of UE 115 can be. In a MIMO system, wireless communication resources may refer to a combination of radio frequency spectrum resources, time resources, and space resources (e.g., space layers), and the use of multiple space layers may further increase the data rate of communication with UE 115.

[0097] A device (e.g., base station 105 or UE 115) of wireless communication system 100 may have a hardware configuration that supports communication on a particular carrier bandwidth, or may be configurable to support communication on one carrier bandwidth in a set of carrier bandwidths. In some examples, wireless communication system 100 may include base stations 105 and / or UEs 115 that may support simultaneous communication via carriers associated with more than one different carrier bandwidths.

[0098] The wireless communication system 100 may support communication with a UE 115 on multiple cells or carriers, a feature that may be referred to as carrier aggregation (CA) or multi-carrier operation. The UE 115 may be configured with multiple downlink component carriers (CCs) and one or more uplink CCs according to a carrier aggregation configuration. Carrier aggregation may be used with both FDD and TDD component carriers.

[0099] In some cases, the wireless communication system 100 may utilize an enhanced component carrier (eCC). An eCC may be characterized by one or more features including a wider carrier or frequency channel bandwidth, a shorter symbol duration, a shorter TTI duration, or a modified control channel configuration. In some cases, an eCC may be associated with a carrier aggregation configuration or a dual connectivity configuration (e.g., when multiple serving cells have suboptimal or non-ideal backhaul links). An eCC may also be configured to be used in an unlicensed spectrum or a shared spectrum (e.g., where more than one operator is allowed to use the spectrum). An eCC characterized by a wide carrier bandwidth may include one or more segments that may be utilized by a UE 115 that is not capable of monitoring the entire carrier bandwidth or is otherwise configured to use a limited carrier bandwidth (e.g., to save power).

[0100] In some cases, an eCC may utilize a different symbol duration than other CCs, which may include using a reduced symbol duration compared to the symbol duration of other CCs. A shorter symbol duration may be associated with an increased spacing between adjacent subcarriers. A device utilizing an eCC (such as a UE 115 or a base station 105) may transmit a wideband signal (e.g., based on a frequency channel or carrier bandwidth of 20, 40, 60, 80 MHz, etc.) with a reduced symbol duration (e.g., 16.67 microseconds). A TTI in an eCC may include one or more symbol periods. In some cases, the TTI duration (i.e., the number of symbol periods in a TTI) may be variable.

[0101] Wireless communication systems (such as NR systems) can utilize any combination of licensed, shared, and unlicensed spectrum bands, etc. The flexibility of eCC symbol duration and subcarrier spacing can allow for the use of eCC across multiple spectrums. In some examples, NR shared spectrum can improve spectrum utilization and spectrum efficiency, particularly through dynamic vertical (e.g., across frequency domain) and horizontal (e.g., across time domain) sharing of resources.

[0102] In some wireless communication systems, a UE 115 may use an NCJT scheme to communicate with one or more TRPs 105 (e.g., a base station 105). The NCJT scheme may implement a joint transmission (JT) to multiple TRPs 105. Various NCJT techniques may have lower requirements for backhaul speed, capacity, latency, etc. between TRPs 105, and may allow transmissions to or from each TRP 105 as independent data streams. A TRP 105 may indicate an NCJT mode for the UE 115 to receive corresponding JTs from the TRP 105 and other TRPs 105. The UE 115 may then simultaneously receive downlink JTs from each TRP 105 based on the indicated NCJT mode, where the downlink JT may be a PDCCH or PDSCH transmission from the TRP 105 to the UE 115 (e.g., based on an RRC configuration). In some cases, a downlink JT may indicate that the UE 115 is to transmit uplink information in response to the downlink JT. For example, it may be desirable for UE 115 to transmit HARQ-ACK feedback to the corresponding TRP 105 after receiving a downlink JT to indicate whether the downlink JT was successfully received and decoded (e.g., ACK indicates successful reception and decoding, while NACK indicates unsuccessful reception and / or decoding).

[0103] Due to non-ideal backhaul between multiple TRPs 105, these TRPs 105 may be semi-statically coordinated with respect to PDSCH, PDCCH, physical uplink control channel (PUCCH), physical uplink shared channel (PUSCH), and / or RS configuration. The non-ideal backhaul may indicate a delay level (e.g., greater than five (5) ms) in communications between the TRPs 105 and a limited capacity of the backhaul link 132. Additionally, the non-ideal backhaul condition may imply that each TRP 105 sends a separate PDCCH and PDSCH to the UE 115, where the PDCCH may appear in different control resource sets (CORESETs) within the same timeslot, and the PDSCH may appear in the same timeslot. Thus, as mentioned above, the UE 115 may transmit HARQ-ACK feedback to each TRP 105 for each PDCCH or PDSCH received.

[0104] In some cases, UE 115 may determine a HARQ-ACK codebook that is used to identify time domain resource allocations for downlink transmissions (e.g., PDCCH or PDSCH) from TRP 105 and to identify when to transmit HARQ-ACK feedback after receiving a downlink transmission. For example, the scheduling TRP 105 may dynamically transmit a downlink control information (DCI) message to UE 115 that indicates information about enabling UE 115 to dynamically construct a HARQ-ACK codebook for each downlink transmission received that requires a HARQ-ACK feedback message transmission. Additionally or alternatively, UE 115 may semi-statically (e.g., RRC signaling) determine the HARQ-ACK codebook based on information from TRP 105, where the codebook does not change between transmissions. In some cases, the HARQ-ACK codebook may be determined based on several parameters, including a cell-specific uplink-downlink configuration, a time domain resource allocation table for PDSCH, a set of k1 values ​​(e.g., PDSCH to HARQ timeline), a number of cells (e.g., in a CA configuration), a PDSCH repetition factor, or a combination thereof. The k1 value may indicate the number of TTIs (e.g., number of time slots) between receiving a downlink channel message (e.g., PDSCH) and transmitting a corresponding HARQ-ACK message. Additionally, an example of a time domain resource allocation table for PDSCH is given below in Table 1. K0 indicates a time slot offset for PDSCH, S indicates a starting symbol for PDSCH, and L indicates a length of PDSCH (e.g., in symbols).

[0105] Table 1 – Default PDSCH time domain resource allocation for normal cyclic prefix

[0106]

[0107]

[0108] In some cases, based on the information in Table 1, UE 115 may determine that two or more PDSCH time domain resource allocations indicate that two or more corresponding PDSCHs have the same end OFDM symbol. Accordingly, it may not be expected that UE 115 receives more than one PDSCH in the same time slot for the two or more allocations. Additionally, UE 115 may determine the HARQ-ACK codebook only when communicating with one TRP 105. In this way, when communicating with multiple TRPs 105, UE 115 may be expected to transmit feedback messages (e.g., HARQ-ACK feedback) to each TRP 105, but may not be able to determine the HARQ-ACK codebook for multiple TRPs 105, or may not be able to transmit multiple feedback messages at the same time. In some cases, UE 115 may select a TRP 105 to respond (e.g., based on priority or similar criteria), or may not respond to any TRP 105. However, suppressing the transmission of one or more feedback messages may result in inefficient communication and unnecessary retransmissions.

[0109] The wireless communication system 100 may support efficient techniques for allocating separate time slots or time durations for corresponding transmissions to separate TRPs 105. For example, a scheduling TRP 105 (e.g., a gNB, a base station 105, a network, etc.) may configure a UE 115 with time slot allocations for PUCCH feedback between different TRPs 105 so that ACK feedback to different TRPs may not occur in the same time slot. Additionally, each TRP 105 may have different parameters (e.g., TRP-specific parameters) for determining a corresponding HARQ-ACK codebook, and the UE 115 may then semi-statically determine the HARQ-ACK codebook for each TRP 105 in each time slot. The TRP-specific uplink parameters may also be the same for each TRP 105 within each time slot, wherein the TRP-specific uplink parameters include QCL information, power control parameters, TA parameters, or a combination thereof. For time domain resource allocations with the same ending OFDM symbol for corresponding PDSCHs, it may not be expected that the UE 115 receives more than one PDSCH from the same TRP 105 in the same time slot, or provides HARQ-ACK feedback for more than one PDSCH in the same HARQ-ACK feedback message in the same time slot.

[0110] Figure 2An example of a wireless communication system 200 that supports ACK codebook design for multiple TRPs according to aspects of the present disclosure is illustrated. In some examples, the wireless communication system 200 can implement aspects of the wireless communication system 100. The wireless communication system 200 can include TRP 105-a, TRP 105-b, and UE 115-a, which can be as described herein with reference to Figure 1 An example of a base station 105 (or TRP) and a UE 115 is described. As described herein, TRP 105-a and TRP 105-b can communicate with UE 115-a at the same time or different times based on the NCJT scheme as described above. Additionally, TRP 105-a and TRP 105-b may have a non-ideal backhaul link 134-a between each other, resulting in each TRP 105 sending a separate PDCCH and / or PDSCH in a separate downlink transmission 205 (e.g., TRP 105-a can send downlink transmission 205-a, and TRP 105-b can send downlink transmission 205-b). UE 115-a may then be expected to transmit HARQ-ACK feedback to each TRP 105 on the uplink transmission 210 to indicate whether the corresponding downlink transmission 205 was received correctly.

[0111] As described herein, in order to prevent multiple uplink messages (e.g., multiple uplink transmissions 210) from being transmitted simultaneously, the time slot allocation may be configured in which ACK / NACK feedback for different TRPs 105 at the time slot level may be semi-statically TDMed. For example, a TRP 105-a (e.g., a master TRP 105, a scheduling TRP 105, a network, etc.) may configure a UE 115-a with time slot allocations for PUCCH feedback between different TRPs 105. In some cases, the time slot allocation may be asymmetric. For example, a first time slot may be allocated to TRP 105-a, a second time slot may be allocated to TRP 105-a, a third time slot may then be allocated to TRP 105-b, a fourth time slot may be allocated back to TRP 105-a, a fifth time slot may also be allocated to TRP 105-a, a fifth time slot may then be allocated to TRP 105-b, and so on. Additionally or alternatively, the time slots may be allocated in an alternating pattern between the two TRPs 105. For example, even-numbered time slots may be allocated to TRP 105-a, while odd-numbered time slots may be allocated to TRP 105-b.

[0112] Based on the time slot allocation, ACK / NACK feedback to different TRPs 105 may not occur in the same time slot, and the network scheduling may ensure that the ACK / NACK feedback is limited to one TRP 105 per time slot. For example, TRP 105-a and TRP105-b (e.g., or any two TRPs 105) may be semi-statically coordinated for HARQ-ACK feedback (e.g., ACK / NACK feedback) on a non-ideal backhaul link 134-a. Additionally, there may be no restrictions on PDSCH scheduling between TRP 105 and UE 115-a. For example, UE 115-a may receive multiple PDSCHs from both TRP 105-a and TRP 105-b in the same time slot. In some cases, time slot allocation may be used for PUSCH and other uplink control information (UCI) (e.g., scheduling request (SR), channel state information (CSI) report, etc.), rather than just for HARQ-ACK transmission. Accordingly, UE 115-a may piggyback UCI (e.g., HARQ-ACK, SR, CSI report, etc.) on the PUSCH.

[0113] Using this timeslot allocation, both dynamic and semi-static HARQ-ACK codebooks can be supported at UE 115-a. For example, UE 115-a can determine HARQ-ACK codebook 215 for TRP 105 in each timeslot. Based on the uplink timeslot allocation between TRPs, UE 115-a can use TRP-specific parameters to determine the semi-static HARQ-ACK codebook for each TRP 105 for a given timeslot. The TRP-specific parameters may be different for each TRP 105. For example, TRP 105-a can have a different number of cells (e.g., in CA), different cell-specific uplink-downlink configurations (e.g., per cell), different time domain resource allocation tables for PDSCH (e.g., per bandwidth part (BWP)), different sets of k1 values ​​(e.g., PDSCH to HARQ timing per BWP), different PDSCH repetition factors, or a combination thereof relative to TRP 105-b. Accordingly, based on signaling from each TRP 105 indicating one or more of the described parameters, the UE 115-a may have a different set of TRP-specific parameters for each TRP 105. In addition to indicating the number of cells supported by the TRP 105, the TRP 105 may also indicate the cell identifiers (IDs) supported by the TRP 105. In this way, the UE 115-a can generate a semi-static HARQ-ACK codebook for a given TRP 105 and can skip a particular cell if the given TRP 105 does not support the cell. For example, TRP 105-a may operate on a first cell (e.g., having a first cell ID), while TRP 105-b may operate on a second cell (e.g., having a second cell ID). Based on the indication of which cells they are operating on, UE 115-a can report HARQ-ACK to TRP 105-a for PDSCH received in cell A (e.g., in the time slot assigned to TRP 105-a) and report HARQ-ACK to TRP 105-b for PDSCH received in cell B (e.g., in the time slot assigned to TRP105-b) based on the corresponding HARQ-ACK codebook generated for each TRP 105.

[0114] After identifying and / or determining TRP-specific parameters for each TRP 105, the UE 115-a may also know which timeslot is assigned to which TRP 105 based on the configured timeslot allocation (e.g., explicitly signaled to the UE 115-a), and may subsequently know which parameters to use to determine the HARQ-ACK codebook 215 for subsequent uplink transmissions (e.g., HARQ-ACK feedback) in the timeslot. Accordingly, the UE 115-a may transmit ACK / NACK feedback on the PUCCH and / or on the PUSCH (e.g., via piggybacking).

[0115] In some cases, the time domain resource allocation table for PDSCH may indicate that two or more PDSCHs may end at the same OFDM symbol. Thus, for time domain resource allocations with the same ending OFDM symbol for corresponding PDSCHs, it may not be expected that UE 115-a receives more than one PDSCH from the same TRP 105 in the same time slot, or provides HARQ-ACK feedback for more than one PDSCH in the same HARQ-ACK feedback message in the same time slot. Additionally or alternatively, UE 115-a may receive two PDSCHs with the same ending OFDM symbol from two different TRPs 105. For example, TRP 105-a may transmit a first PDSCH, and TRP 105-b may transmit a second PDSCH, where both PDSCHs end on the same OFDM symbol. Accordingly, it may be expected that UE 115-a receives each PDSCH from the corresponding TRP 105, even if they end on the same OFDM symbol.

[0116] Additionally or alternatively, it may not be desirable for UE 115-a to receive more than one PDSCH in the same timeslot on overlapping time domain resource allocations. For example, if two or more PDSCHs (e.g., PDSCH opportunities) overlap in time (e.g., regardless of whether the PDSCHs end on the same OFDM symbol), UE 115-a may feedback one (1) HARQ-ACK for a given TRP 105. In this way, UE 115-a may transmit HARQ-ACK feedback for the first PDSCH received in the timeslot, but not transmit HARQ-ACK feedback for any subsequent PDSCHs received in the same timeslot that overlap with the first PDSCH in the time domain. Additionally, in some cases, UE 115-a may determine to transmit a single HARQ-ACK feedback for the first PDSCH based on the overlapping PDSCHs being received from the same TRP 105.

[0117] Additionally, one or more TRP-specific uplink parameters may vary per timeslot or per TRP 105. For example, QCL information for the PUCCH may be configured per PUCCH resource (within a timeslot). The QCL information may determine spatial domain parameters for PUCCH transmission. In order to support semi-static TDM of PUCCH for multiple TRPs 105, UE 115-a may need to apply different QCL parameters (e.g., QCL information) to different timeslots (e.g., depending on the timeslot allocation between TRPs 105). For example, in timeslot n, if timeslot n is an uplink timeslot allocated to TRP 105-a, UE 115-a may follow the corresponding QCL conditions for PUCCH transmission. This QCL consideration may be used for frequency range 2 (FR2) (e.g., a range for mmW communications). If QCL information is not configured for the PUCCH (e.g., in frequency range 1 (FR1)), UE 115-a may use the same QCL parameters for PUCCH transmissions to different TRPs 105 (e.g., TRP 105-b). Additionally, other TRP-specific uplink parameters may be applied to different time slots per TRP 105. For example, different power control parameters may be applied to different time slots (e.g., depending on the time slot allocation between TRPs 105) and / or different TAs may be assumed in different time slots. In some cases, one or more TRP-specific uplink parameters may be signaled to UE 115-a via DCI and semi-static messaging (e.g., RRC signaling).

[0118] Figure 3 An example of a time slot allocation 300 that supports HARQ ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is illustrated. In some examples, the time slot allocation 300 can implement aspects of the wireless communication systems 100 and / or 200. As described herein, the time slot allocation 300 can be configured for a UE 115 to receive one or more downlink messages from multiple TRPs 105 and then transmit an uplink message to each TRP 105 within a separate time slot allocated to the corresponding TRP 105.

[0119] The UE 115 may be configured with an opportunity 305-a for a first TRP A (e.g., the first TRP 105), and the UE 115 may be configured with an opportunity 305-b for a second TRP B (e.g., the second TRP 105). Each opportunity 305 may occupy a different BWP or a different set of RBs of the total bandwidth so that the two opportunities 305 occupy separate frequencies. Additionally or alternatively, the opportunities 305 from different TRPs may occupy the same time and frequency resources and may be separated in the spatial domain using different spatial layers (e.g., in the case where the UE 115 supports MIMO reception). In this way, the UE 115 may receive multiple PDSCHs 310 from both TRP A and TRP B on different resources (e.g., based on different BWPs, RBs, spatial layers, etc.) within the same time slot. For example, the UE 115 may receive a first PDSCH 310-a from TRP A and a second PDSCH 310-b from TRP B within time slot n. Additionally, the UE 115 may receive a third PDSCH 310-c from TRP A and a fourth PDSCH 310-d from TRP B in time slot n+1. In some cases, it may be desirable for the UE 115 to transmit HARQ-ACK feedback for each PDSCH 310 to the corresponding TRP. However, if the UE 115 were to transmit multiple PUCCHs 315 to each TRP in the same time slot, a collision may occur that impairs one or both PUCCHs 315. In some cases, the UE 115 may not be able to determine separate HARQ-ACK codebooks for separate TRPs in the same time slot (e.g., based on separate TRP-specific parameters for determining the HARQ-ACK codebooks). Additionally or alternatively, the UE 115 may not be able to determine separate HARQ-ACK codebooks for separate TRPs based on separate TRPs having different TRP-specific uplink parameters. Accordingly, UE 115 may be unable to or may refrain from transmitting PUCCH 315 to more than one TRP at a time.

[0120] The scheduling TRP or base station 105 may configure UE 115 with time slot allocations for PUCCH 315 feedback between different TRPs. For example, time slot n+2 may be allocated for a first PUCCH 315-a, which is transmitted to TRP A for HARQ-ACK feedback for a first PDSCH 310-a and a third PDSCH 310-c. Additionally, time slot n+3 may be allocated for a second PUCCH 315-b, which is transmitted to TRP B for HARQ-ACK feedback for a second PDSCH 310-b and a fourth PDSCH 310-d. The scheduling TRP or base station 105 may explicitly indicate to UE 115 which time slot is allocated to which TRP. In some cases, each TRP may indicate a time slot for transmitting HARQ-ACK feedback for the corresponding PDSCH 310 via a DCI containing a scheduling grant for the corresponding PDSCH 310. For example, the TRP may transmit a DCI with a corresponding k1 value to indicate the time slot in which the corresponding PUCCH 315 is to be transmitted for the PDSCH 310. As shown in the example of the time slot allocation 300, the k1 value indicated in the DCI for the first PDSCH 310-a may be two (2) time slots, while the k1 value indicated in the DCI for the third PDSCH 310-c may be one (1) time slot, indicating that the first PUCCH 315-a is to be transmitted two (2) time slots after receiving the first PDSCH 310-a and one (1) time slot after receiving the third PDSCH 310-c. Additionally or alternatively, the k1 value indicated in the DCI of the second PDSCH 310-b may be three (3) time slots, and the k1 value indicated in the DCI of the fourth PDSCH 310-d may be two (2) time slots, indicating that the second PUCCH 315-b is to be transmitted three (3) time slots after receiving the second PDSCH 310-b and two (2) time slots after receiving the fourth PDSCH 310-d.

[0121] As described herein, the UE 115 may determine a separate HARQ-ACK codebook for each uplink timeslot (e.g., timeslot n+2 and timeslot n+3). Each TRP may have different TRP-specific parameters, resulting in the UE 115 determining a separate HARQ-ACK codebook for each uplink timeslot corresponding to the assigned TRP. In some cases, the HARQ-ACK feedback may be transmitted by piggybacking the HARQ-ACK feedback on the PUSCH rather than being transmitted in the PUCCH 315. Additionally, each PUCCH 315 may have the same TRP-specific uplink parameters (e.g., QCL information, power control parameters, TA parameters, etc.), as described above with reference to FIG. Figure 2 Accordingly, each uplink time slot may have the same HARQ-ACK codebook and the same TRP-specific uplink parameters for messages transmitted in each PUCCH 315 (eg, ACK / NACK feedback for each PDSCH 310).

[0122] Figure 4 An example of a downlink channel schedule 400 supporting an ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is illustrated. In some examples, the downlink channel schedule 400 can implement aspects of the wireless communication systems 100 and / or 200. The downlink channel schedule 400 can illustrate one or more PDSCHs 405 received at a UE 115 in multiple time slots 410 from one or more TRPs 105 (e.g., base stations 105).

[0123] As shown, UE 115 may receive a first PDSCH 405-a in a first time slot 410-a. In some cases, the first PDSCH 405-a may be the only downlink transmission received by UE 115 in time slot 410-a. As such, UE 115 may be able to successfully decode the first PDSCH 405-a without any interference from additional downlink messages. Alternatively, UE 115 may receive a second PDSCH 405-b, a third PDSCH 405-c, and a fourth PDSCH 405-d in a second time slot 410-b. UE 115 may select a first PDSCH 405-a, a second PDSCH 405-b, a third PDSCH 405-c, and a fourth PDSCH 405-d based on the above (e.g., Figure 1 The time domain resource allocation table for PDSCH described in Table 1) in FIG. 1 determines the end point of each PDSCH 405. Accordingly, the UE 115 can determine that the second PDSCH 405-b ends at a codeword that does not overlap with any other PDSCH 405, and thus, the information in the second PDSCH 405-b can be received and decoded.

[0124] Alternatively, the UE 115 may determine that both the third PDSCH 405-c and the fourth PDSCH 405-d may have the same end OFDM symbol 415. In some cases, the third PDSCH 405-c and the fourth PDSCH 405-d may not be received from the same TRP. Thus, it may not be expected that the UE 115 receives more than one PDSCH 405 with the same end OFDM symbol from the same TRP in the same time slot 410. Additionally, it may not be expected that the UE 115 provides HARQ-ACK feedback for more than one PDSCH 405 with the same end OFDM symbol in the same HARQ-ACK feedback message in the same time slot. For example, the UE 115 may receive one of the third PDSCH 405-c and the fourth PDSCH 405-d from one TRP, and may then transmit HARQ-ACK feedback for the selected PDSCH 405 within the corresponding uplink time slot allocated to the TRP. However, in some cases, the UE 115 may receive the third PDSCH 405-c from the first TRP and may receive the fourth PDSCH 405-d from the second TRP. Accordingly, the UE 115 may transmit HARQ-ACK feedback for the third PDSCH 405-c in a first time slot corresponding to the first TRP (e.g., based on the time slot allocation per TRP as described herein) and may transmit HARQ-ACK feedback for the fourth PDSCH 405-d in a different time slot corresponding to the second TRP (e.g., different from the first time slot corresponding to the first TRP).

[0125] Additionally or alternatively, if two or more PDSCHs 405 (e.g., PDSCH opportunities) overlap in time (e.g., regardless of whether the PDSCHs 405 end on the same OFDM symbol), the UE 115 may feedback one (1) HARQ-ACK for a given TRP. That is, it may not be expected that the UE 115 receives more than one PDSCH 405 in the same time slot 410 on overlapping time domain resource allocations. Thus, based on the fact that both the third PDSCH 405-c and the fourth PDSCH 405-d overlap with the second PDSCH 405-b in the time domain, the UE 115 may transmit HARQ-ACK feedback for the second PDSCH 405-b received in the second time slot 410-b, but not transmit HARQ-ACK feedback for the third PDSCH 405-c and the fourth PDSCH 405-d. Additionally, in some cases, the UE 115 may determine to transmit a single HARQ-ACK feedback for the second PDSCH 405-b based on the second PDSCH 405-b, the third PDSCH 405-c, and the fourth PDSCH 405-d being received from the same TRP.

[0126] Figure 5 An example of an uplink channel repetition configuration 500 supporting an ACK codebook design for multiple TRPs in accordance with various aspects of the present disclosure is illustrated. In some examples, the uplink channel repetition configuration 500 can implement various aspects of the wireless communication system 100 and / or 200. In some cases, when the UE 115 transmits HARQ-ACK feedback for a received PDSCH, the UE 115 can transmit the HARQ-ACK feedback in a PUCCH 505 (e.g., or a PUSCH). However, as described above, the UE 115 can transmit the PUCCH 505 on multiple time slots 510 (e.g., time slot aggregation, PUCCH repetition, etc.), and some of the time slots 510 can be allocated to different TRPs. In some cases, the time slot allocations for different TRPs can be configured and signaled via higher layer signaling (e.g., configured RRC).

[0127] For example, as shown, UE 115 may be scheduled to transmit a first PUCCH 505-a in a first time slot 510-a, a second PUCCH 505-b in a second time slot 510-b, a third PUCCH 505-c in a third time slot 510-c, and a fourth PUCCH 505-d in a fourth time slot 510-d to a first TRP (e.g., TRP A) (e.g., four (4) repetitions of PUCCH / PUSCH in four (4) separate time slots, such that K=4). However, the second time slot 510-b and the fourth time slot 510-d may be allocated to a second TRP (e.g., TRP B). Accordingly, UE 115 may encounter problems when determining which time slot 510 to transmit PUCCH 505 (e.g., PUCCH repetition) to TRP A based on the time slot 510 being allocated to a time slot other than TRP A.

[0128] In some cases, as described herein, the UE 115 may transmit a PUCCH 505 for TRP A in the time slot 510 allocated to the TRP A, and may skip PUCCH 505 transmissions in time slots 510 allocated to other TRP(s). Additionally, the skipped PUCCH 505 transmissions may not be postponed to other time slots 510. For example, as shown, the UE 115 may transmit a first PUCCH 505-a in a first time slot 510-a and a third PUCCH 505-c in a third time slot 510-c (e.g., transmitting two repetitions of the PUCCH 505). Additionally or alternatively, the UE 115 may transmit K PUCCHs 505, where K is a configured repetition factor (e.g., as described above in Figure 5 , K=4). Accordingly, UE 115 may defer the PUCCH 505 transmissions skipped in the second time slot 510-b and the fourth time slot 510-d to other time slots 510 allocated to TRP A. For example, UE 115 may use the time slots 510 allocated to TRP A (e.g., the first time slot 510-a, the third time slot 510-c, the fifth time slot 510-e, and the seventh time slot 510) to transmit four (4) repetitions of PUCCH 505.

[0129] Additionally or alternatively, as long as the starting time slot 510 (e.g., the first time slot 510) is allocated to the intended TRP (e.g., TRP A), the UE 115 may transmit the PUCCH 505 in K consecutive time slots. Accordingly, it may not be expected that the UE 115 dynamically schedules any other uplink transmissions (e.g., Figure 5510-b and the fourth time slot 510-d for TRP B in the example of FIG. 510-4 , and the UE 115 can use these time slots 510 to transmit PUCCH 505 (e.g., PUCCH repetitions, PUSCH, PUSCH repetitions, etc.). In some cases, in the time slots 510 allocated to other TRPs (e.g., Figure 5 d) for TRP B in the example of the second time slot 510-b and the fourth time slot 510-d may be discarded (e.g., due to a conflict with a transmission / repetition of PUCCH 505 to TRP A). Thus, UE 115 may transmit a first PUCCH 505-a in the first time slot 510-a, a second PUCCH 505-b in the second time slot 510-b, a third PUCCH 505-c in the third time slot 510-c, and a fourth PUCCH 505-d in the fourth time slot 510-d to TRP A, even though the second time slot 510-b and the fourth time slot 510-d are (e.g., semi-statically) allocated to TRP B. Additionally or alternatively, UE 115 may not expect any of the scheduled time slots 510 to be allocated to other TRPs. For example, base station 105 may indicate that K consecutive time slots are allocated to the same TRP (e.g., TRP A). Thus, UE 115 may consider Figure 5 The example shown in is an error situation because the second time slot 510-b and the fourth time slot 510-d are allocated to TRP B.

[0130] In some cases, the UE 115 may determine which configuration will be used to transmit HARQ-ACK feedback in the time slot 510 (e.g., in PUCCH 505, PUSCH, PUCCH / PUSCH repetitions, etc.) based on signaling from the base station 105 (e.g., serving base station 105). For example, the base station 105 may signal via higher layer signaling (e.g., RRC signaling), DCI, or additional types of downlink signaling which time slots will be used to transmit HARQ-ACK feedback to the TRP (e.g., base station 105).

[0131] Figure 6 An example of a process flow 600 for supporting ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is illustrated. In some examples, the process flow 600 can implement aspects of the wireless communication system 100 and / or 200. The process flow 600 can include a TRP 105-c and a UE 115-b, which can be as described herein with reference to Figure 1-5Examples of TRPs 105 (e.g., base stations 105) and UEs 115 are described. As described herein, UE 115-b may be configured to communicate with multiple TRPs 105 (e.g., including TRP 105-c) simultaneously or at different times.

[0132] In the following description of process flow 600, the operations between UE 115-b and TRP 105-c may be performed in a different order or at a different time. Certain operations may also be excluded from process flow 600, or other operations may be added to process flow 600. It is understood that although UE 115-b and TRP 105-c are shown as performing several operations of process flow 600, any wireless device may perform the operations shown.

[0133] At 605, UE 115-b may receive an allocation of time slots to provide HARQ-ACK feedback to multiple TRPs 105. In some cases, UE 115-b may receive an allocation of time slots to be used to provide HARQ-ACK feedback to different TRPs 105 in the multiple TRPs 105, wherein each time slot identified in the time slot allocation is allocated for feedback transmission by UE 115-b to only one TRP 105 (e.g., TRP 105-c) in the multiple TRPs 105. Additionally or alternatively, UE 115-b may receive an allocation of time slots to be used to provide HARQ-ACK feedback to different TRPs 105 in the multiple TRPs 105, wherein the time slots are allocated asymmetrically between the multiple TRPs 105. In some cases, UE 115-b may receive the time slot allocation via RRC signaling.

[0134] Additionally, in some cases, TRP 105-c may identify a time slot allocation for at least one time slot to be used by UE 115-b to provide HARQ-ACK feedback to TRP 105-c. Accordingly, TRP 105-c may transmit the time slot allocation to one or more other TRPs 105 in communication with UE 115-b to facilitate time slot allocation coordination between TRP 105-c and the one or more other TRPs 105. Additionally, TRP 105-c may receive an additional time slot allocation from the one or more other TRPs 105 identifying a time slot to be used by UE 115-b to provide HARQ-ACK feedback to the one or more other TRPs 105, wherein each time slot identified in the time slot allocation and the additional time slot allocation is allocated for feedback transmission by UE 115-b to only one TRP 105.

[0135] At 610 , UE 115 - b may receive a DCI message including an indication of the size of the HARQ-ACK codebook.

[0136] At 615, UE 115-b may determine a TRP-specific HARQ-ACK codebook for feedback transmission to TRP 105-c among the plurality of TRPs 105 based on the timeslot allocation. In some cases, UE 115-b may determine the TRP-specific HARQ-ACK codebook based on the DCI message received at 610. Additionally or alternatively, UE 115-b may determine the TRP-specific HARQ-ACK codebook based on at least one TRP-specific parameter received semi-statically. For example, at least one TRP-specific parameter may include one or more of the following: the number of cellular cells for CA supported by TRP 105-c, the cellular cell-specific uplink-downlink configuration associated with the cellular cell of TRP 105-c, a per-BWP table of time domain resource allocation for PDSCH for TRP 105-c, a per-BWP parameter set (e.g., k1 value) defining PDSCH to feedback timing for TRP 105-c, or a per-BWP PDSCH repetition factor for TRP 105-c.

[0137] In some cases, UE 115-b may determine a TRP-specific HARQ-ACK codebook based on comparing the time slot allocation with a cell-specific uplink-downlink configuration associated with the cell of TRP 105-c, wherein the corresponding time slot is used to transmit the feedback to TRP 105-c only if the corresponding time slot is identified as an uplink time slot or a flexible time slot by the cell-specific uplink-downlink configuration. Additionally or alternatively, UE 115-b may determine a TRP-specific HARQ-ACK codebook based on comparing the time slot allocation with a cell-specific uplink-downlink configuration associated with the cell of TRP 105-c, wherein the corresponding time slot is used to transmit the feedback to TRP 105-c only if the codewords allocated for feedback transmission in the corresponding time slot are also allocated for uplink transmission or flexible transmission by the cell-specific uplink-downlink configuration.

[0138] At 620, UE 115-b may determine one or more TRP-specific uplink parameters for feedback transmissions to TRP 105-c. For example, UE 115-b may identify that the QCL information is configured for PUCCH transmission, and may then identify the TRP-specific QCL information for TRP 105-c for the corresponding time slot. Additionally or alternatively, UE 115-b may identify TRP-specific power control parameters for transmissions to TRP 105-c for the corresponding time slot. Additionally or alternatively, UE 115-b may identify TRP-specific TA parameters for transmissions to TRP 105-c for the corresponding time slot.

[0139] At 625, UE 115-b may transmit feedback to TRP 105-c using the corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. In some cases, UE 115-b may transmit the feedback via at least one of: via PUCCH, or via PUSCH as piggybacked UCI. Additionally, the feedback transmitted to TRP 105-c using the corresponding time slot may include feedback information related to only one PDSCH in multiple time domain resource allocations having the same ending OFDM codeword.

[0140] In some cases, UE 115-b may identify only one PDSCH receive opportunity from TRP 105-c per time slot per cell for time domain resource allocations that overlap in time (e.g., may additionally have the same ending OFDM symbol). In this way, UE 115-b may receive one PDSCH transmission associated with the identified PDSCH receive opportunity from TRP 105-c, wherein feedback to be transmitted in the corresponding time slot includes feedback information related to one PDSCH reception or PDSCH transmission. Additionally or alternatively, UE 115-b may receive an additional PDSCH from an additional TRP 105 among multiple TRPs 105, the additional PDSCH having a time domain resource allocation in the same CC that overlaps with the PDSCH received from TRP 105-c. Accordingly, UE 115-b may transmit HARQ-ACK feedback to the additional TRP 105 in the time slot allocated for the additional TRP 105.

[0141] Additionally, in some cases, UE 115-b may determine that a set of HARQ-ACK feedback messages (e.g., multiple PUCCHs, PUSCHs, PUCCH repetitions, PUSCH repetitions, etc.) are to be transmitted to a TRP in a group of TRPs. Subsequently, UE 115-b may identify a set of time slots in which the set of HARQ-ACK feedback messages are to be transmitted to the TRP based on the time slot allocation, and may transmit the set of HARQ-ACK feedback messages to the TRP in the identified set of time slots. For example, the set of time slots may include: time slots allocated only to the TRP in the group of TRPs, several consecutive time slots allocated to any TRP in the group of TRPs, several consecutive time slots allocated to the TRP in the group of TRPs, or a combination thereof.

[0142] At 630, UE 115-b may transmit additional information to TRP 105-c using the corresponding time slot identified by the time slot allocation. In some cases, the additional information may take the form of: PUSCH payload, SR, or CSI report. Additionally or alternatively, the feedback may be combined with the additional information on a single uplink channel.

[0143] Figure 7 A block diagram 700 of a device 705 supporting an ACK codebook design for multiple TRPs according to aspects of the present disclosure is shown. The device 705 may be an example of aspects of a UE 115 as described herein. The device 705 may include a receiver 710, a UE codebook manager 715, and a transmitter 720. The device 705 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0144] The receiver 710 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to ACK codebook design for multiple TRPs, etc.). The information may be passed to other components of the device 705. The receiver 710 may be a reference Fig.10 Examples of various aspects of the transceiver 1020 are described. The receiver 710 may utilize a single antenna or a collection of antennas.

[0145] The UE codebook manager 715 may receive a time slot allocation for the UE to provide HARQ-ACK feedback to a set of TRPs. In some cases, the UE codebook manager 715 may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation. Additionally, the UE codebook manager 715 may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The UE codebook manager 715 may then use the corresponding time slot identified by the time slot allocation and use the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters to transmit feedback to the TRP. The UE codebook manager 715 may be an example of various aspects of the UE codebook manager 1010 described herein.

[0146] The UE codebook manager 715 or its subcomponents may be implemented in hardware, code executed by a processor (e.g., software or firmware), or any combination thereof. If implemented in code executed by a processor, the functions of the UE codebook manager 715 or its subcomponents may be performed by a general purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device (PLD), discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described in the present disclosure.

[0147] The UE codebook manager 715 or its subcomponents may be physically located at various locations, including being distributed so that portions of functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of the present disclosure, the UE codebook manager 715 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of the present disclosure, the UE codebook manager 715 or its subcomponents may be combined with one or more other hardware components (including, but not limited to, input / output (I / O) components, transceivers, network servers, another computing device, one or more other components described in the present disclosure, or a combination thereof).

[0148] The transmitter 720 may transmit signals generated by other components of the device 705. In some examples, the transmitter 720 may be co-located with the receiver 710 in a transceiver module. For example, the transmitter 720 may be a reference Fig.10 Examples of various aspects of the transceiver 1020 are described. The transmitter 720 may utilize a single antenna or a collection of antennas.

[0149] In some examples, the UE codebook manager 715 may be implemented as an integrated circuit or chipset for a mobile device modem, and the receiver 710 and transmitter 720 may be implemented as analog components (e.g., amplifiers, filters, antennas) coupled to the mobile device modem to enable wireless transmission and reception on one or more frequency bands.

[0150] The UE codebook manager 715 as described herein may be implemented to achieve one or more potential advantages. One implementation may allow the device 705 to receive a time slot allocation for transmitting ACK feedback to a base station. The ACK feedback may include a corresponding time slot identified by the time slot allocation and a HARQ ACK codebook that varies by TRP. The feedback may improve reliability and reduce latency during feedback transmission.

[0151] Based on the techniques for implementing feedback for no-grant uplink transmission as described herein, a processor of UE 115 (e.g., controlling receiver 710, transmitter 720, or as described in reference to Fig.10 The described transceiver 1020) can improve reliability and reduce signaling overhead when conveying feedback because the UE 115 can avoid going through unnecessary configuration procedures during retransmissions.

[0152] Figure 8 A block diagram 800 of a device 805 supporting an ACK codebook design for multiple TRPs according to aspects of the present disclosure is shown. The device 805 may be an example of aspects of the device 705 or UE 115 as described herein. The device 805 may include a receiver 810, a UE codebook manager 815, and a transmitter 840. The device 805 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0153] The receiver 810 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to ACK codebook design for multiple TRPs, etc.). The information may be passed to other components of the device 805. The receiver 810 may be a reference Fig.10 Examples of various aspects of the transceiver 1020 are described. The receiver 810 may utilize a single antenna or a collection of antennas.

[0154] The UE codebook manager 815 may be an example of aspects of the UE codebook manager 715 described herein. The UE codebook manager 815 may include a slot allocation receiver 820, a HARQ-ACK codebook component 825, an uplink parameter component 830, and a feedback transmitter 835. The UE codebook manager 815 may be an example of aspects of the UE codebook manager 1010 described herein.

[0155] The timeslot allocation receiver 820 may receive timeslot allocations for the UE to provide HARQ-ACK feedback to a set of TRPs.

[0156] The HARQ-ACK codebook component 825 can determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the group of TRPs based on the time slot allocation.

[0157] The uplink parameters component 830 can determine one or more TRP-specific uplink parameters for feedback transmissions to the TRP.

[0158] The feedback transmitter 835 may transmit feedback to the TRP using the corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0159] The transmitter 840 may transmit signals generated by other components of the device 805. In some examples, the transmitter 840 may be co-located with the receiver 810 in a transceiver module. For example, the transmitter 840 may be a reference Fig.10 Examples of various aspects of the transceiver 1020 are described. The transmitter 840 may utilize a single antenna or a collection of antennas.

[0160] In some examples, the UE codebook manager 815 may be implemented as an integrated circuit or chipset for a mobile device modem, and the receiver 810 and transmitter 840 may be implemented as analog components (e.g., amplifiers, filters, antennas) coupled to the mobile device modem to enable wireless transmission and reception on one or more frequency bands.

[0161] The UE codebook manager 815 as described herein may be implemented to achieve one or more potential advantages. One implementation may allow the device 805 to receive a time slot allocation for transmitting ACK feedback to a base station. The ACK feedback may include a corresponding time slot identified by the time slot allocation and a HARQ ACK codebook that varies by TRP. The feedback may improve reliability and reduce latency during feedback transmission.

[0162] Based on the techniques for implementing feedback for no-grant uplink transmission as described herein, the processor of the UE 115 (e.g., controlling the receiver 710, the transmitter 840, or as described in reference to Fig.10 The described transceiver 1020) can improve reliability and reduce signaling overhead when conveying feedback because the UE 115 can avoid going through unnecessary configuration procedures during retransmissions.

[0163] Fig. 9A block diagram 900 of a UE codebook manager 905 supporting ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is shown. The UE codebook manager 905 may be an example of aspects of the UE codebook manager 715, the UE codebook manager 815, or the UE codebook manager 1010 described herein. The UE codebook manager 905 may include a slot allocation receiver 910, a HARQ-ACK codebook component 915, an uplink parameter component 920, a feedback transmitter 925, a DCI component 930, a semi-static HARQ-ACK codebook component 935, and an uplink information component 940. Each of these modules may communicate directly or indirectly with each other (e.g., via one or more buses).

[0164] The timeslot allocation receiver 910 may receive a timeslot allocation for a UE to provide HARQ-ACK feedback to a group of TRPs. In some examples, the timeslot allocation receiver 910 may receive an allocation of timeslots to be used by the UE to provide HARQ-ACK feedback to different TRPs in a group of TRPs, wherein each timeslot identified in the timeslot allocation is allocated for feedback transmission by the UE to only one TRP in the group of TRPs. Additionally or alternatively, the timeslot allocation receiver 910 may receive an allocation of timeslots to be used by the UE to provide HARQ-ACK feedback to different TRPs in a group of TRPs, wherein the timeslots are allocated asymmetrically between the group of TRPs. In some examples, the timeslot allocation receiver 910 may receive the timeslot allocation via RRC signaling.

[0165] The HARQ-ACK codebook component 915 can determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the group of TRPs based on the time slot allocation. In some examples, the HARQ-ACK codebook component 915 can compare the time slot allocation with the cell-specific uplink-downlink configuration associated with the cell of the TRP, wherein the corresponding time slot is used to transmit the feedback to the TRP only if the corresponding time slot is identified as an uplink time slot by the cell-specific uplink-downlink configuration. Additionally or alternatively, the HARQ-ACK codebook component 915 can compare the time slot allocation with the cell-specific uplink-downlink configuration associated with the cell of the TRP, wherein the corresponding time slot is used to transmit the feedback to the TRP only if the codewords allocated for feedback transmission in the corresponding time slot are also allocated for uplink transmission by the cell-specific uplink-downlink configuration.

[0166] The uplink parameters component 920 can determine one or more TRP-specific uplink parameters for feedback transmissions to the TRP. In some examples, the uplink parameters component 920 can identify that the QCL information is configured for PUCCH transmission, and can identify TRP-specific QCL information for the TRP for the corresponding time slot. Additionally or alternatively, the uplink parameters component 920 can identify TRP-specific power control parameters for transmissions to the TRP for the corresponding time slot. In some cases, the TRP-specific power control parameters may include at least one of an open-loop power control parameter and a closed-loop power control parameter. Additionally or alternatively, the uplink parameters component 920 can identify TRP-specific TA parameters for transmissions to the TRP for the corresponding time slot.

[0167] The feedback transmitter 925 may transmit feedback to the TRP using the corresponding time slot identified by the time slot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. In some examples, the feedback transmitter 925 may transmit the feedback via at least one of the following: via PUCCH, or via PUSCH as piggybacked UCI. Additionally or alternatively, the feedback transmitted to the TRP using the corresponding time slot may include feedback information related to only one PDSCH in multiple time domain resource allocations with the same end OFDM codeword.

[0168] In some cases, the feedback transmitter 925 may determine that a set of HARQ-ACK feedback messages are to be transmitted to a TRP in the group of TRPs. Subsequently, the feedback transmitter 925 may identify a set of time slots to transmit the set of HARQ-ACK feedback messages to the TRP based on the time slot allocation, and may transmit the set of HARQ-ACK feedback messages to the TRP in the identified set of time slots. Additionally, the set of time slots may include: time slots allocated only to the TRP in the group of TRPs, several consecutive time slots allocated to any TRP in the group of TRPs, several consecutive time slots allocated to the TRP in the group of TRPs, or a combination thereof.

[0169] DCI component 930 may receive a DCI message including an indication of the size of the HARQ-ACK codebook.

[0170] The semi-static HARQ-ACK codebook component 935 can determine the TRP-specific HARQ-ACK codebook based on at least one TRP-specific parameter received semi-statically. In some cases, the at least one TRP-specific parameter may include one or more of the following: the number of cellular cells for CA supported by the TRP, the cellular cell-specific uplink-downlink configuration associated with the cellular cell of the TRP, a per-BWP table of time domain resource allocation for the PDSCH for the TRP, a per-BWP parameter set defining the PDSCH to feedback timing for the TRP, or a per-BWP PDSCH repetition factor for the TRP.

[0171] In some examples, the semi-static HARQ-ACK codebook component 935 can identify only one PDSCH reception opportunity from the TRP per cell per time slot for time domain resource allocations with the same end OFDM symbol. Accordingly, the semi-static HARQ-ACK codebook component 935 can receive one PDSCH transmission associated with the identified PDSCH reception opportunity from the TRP, wherein the feedback to be transmitted in the corresponding time slot includes feedback information related to one PDSCH reception or PDSCH transmission.

[0172] Additionally or alternatively, the semi-static HARQ-ACK codebook component 935 can receive an additional PDSCH from an additional TRP in the set of TRPs, the additional PDSCH having the same ending OFDM symbol in the same CC as the PDSCH received from the TRP. Accordingly, the semi-static HARQ-ACK codebook component 935 can transmit HARQ-ACK feedback to the additional TRP in a time slot allocated for the additional TRP.

[0173] The uplink information component 940 can transmit additional information to the TRP using the corresponding time slot identified by the time slot allocation. In some cases, the additional information can take the form of: PUSCH payload, SR or CSI report. Additionally, the feedback can be combined with the additional information on a single uplink channel.

[0174] Fig.10A diagram of a system 1000 including a device 1005 supporting an ACK codebook design for multiple TRPs according to various aspects of the present disclosure is shown. The device 1005 may be an example of a device 705, a device 805, or a UE 115 as described herein or include components thereof. The device 1005 may include components for two-way voice and data communications, including components for transmitting and receiving communications, including a UE codebook manager 1010, an I / O controller 1015, a transceiver 1020, an antenna 1025, a memory 1030, and a processor 1040. These components may be in electronic communication via one or more buses (e.g., a bus 1045).

[0175] The UE codebook manager 1010 may receive a timeslot allocation for the UE to provide HARQ-ACK feedback to a set of TRPs. In some cases, the UE codebook manager 1010 may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the timeslot allocation. Additionally, the UE codebook manager 1010 may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The UE codebook manager 1010 may then transmit feedback to the TRP using the corresponding timeslot identified by the timeslot allocation and using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters.

[0176] I / O controller 1015 can manage input and output signals of device 1005. I / O controller 1015 can also manage peripheral devices that are not integrated into device 1005. In some cases, I / O controller 1015 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 1015 can utilize an operating system, such as Or another known operating system. In other cases, I / O controller 1015 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 1015 may be implemented as part of a processor. In some cases, a user may interact with device 1005 via I / O controller 1015 or via hardware components controlled by I / O controller 1015.

[0177] The transceiver 1020 may communicate bidirectionally via one or more antennas, wired or wireless links, as described herein. For example, the transceiver 1020 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1020 may also include a modem to modulate packets and provide the modulated packets to an antenna for transmission, and demodulate packets received from an antenna.

[0178] In some cases, a wireless device may include a single antenna 1025. However, in some cases, the device may have more than one antenna 1025, which may be capable of transmitting or receiving multiple wireless transmissions concurrently.

[0179] Memory 1030 may include random access memory (RAM) and read-only memory (ROM). Memory 1030 may store computer-readable, computer-executable code 1035 including instructions that, when executed, cause the processor to perform the various functions described herein. In some cases, memory 1030 may include, among other things, a basic I / O system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0180] Processor 1040 may include an intelligent hardware device (e.g., a general purpose processor, a DSP, a central processing unit (CPU), a microcontroller, an ASIC, an FPGA, a PLD, discrete gate or transistor logic components, discrete hardware components, or any combination thereof). In some cases, processor 1040 may be configured to operate a memory array using a memory controller. In other cases, the memory controller may be integrated into processor 1040. Processor 1040 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1030) to cause device 1005 to perform various functions (e.g., functions or tasks supporting ACK codebook design for multiple TRPs).

[0181] The code 1035 may include instructions for implementing various aspects of the present disclosure, including instructions for supporting wireless communications. The code 1035 may be stored in a non-transitory computer-readable medium, such as a system memory or other type of memory. In some cases, the code 1035 may not be directly executed by the processor 1040, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0182] Fig.11 A block diagram 1100 of a device 1105 supporting an ACK codebook design for multiple TRPs according to aspects of the present disclosure is shown. The device 1105 may be an example of aspects of a base station 105 as described herein. The device 1105 may include a receiver 1110, a TRP timeslot allocation manager 1115, and a transmitter 1120. The device 1105 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0183] The receiver 1110 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to ACK codebook design for multiple TRPs, etc.). The information may be passed to other components of the device 1105. The receiver 1110 may be a reference Fig.14 Examples of various aspects of the transceiver 1420 are described. The receiver 1110 may utilize a single antenna or a collection of antennas.

[0184] The TRP timeslot allocation manager 1115 may identify, at the TRP, a timeslot allocation for at least one timeslot that will be used by the UE to provide HARQ-ACK feedback to the TRP. The TRP timeslot allocation manager 1115 may then transmit a downlink message to the UE. Additionally, the TRP timeslot allocation manager 1115 may transmit an indication that the UE will use the at least one timeslot identified by the timeslot allocation to provide HARQ-ACK feedback. In some cases, the TRP timeslot allocation manager 1115 may then receive HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot allocation. The TRP timeslot allocation manager 1115 may be an example of various aspects of the TRP timeslot allocation manager 1410 described herein.

[0185] The TRP timeslot allocation manager 1115 or its subcomponents may be implemented in hardware, in code executed by a processor (e.g., software or firmware), or any combination thereof. If implemented in code executed by a processor, the functions of the TRP timeslot allocation manager 1115 or its subcomponents may be performed by a general purpose processor, DSP, ASIC, FPGA or other PLD designed to perform the functions described in the present disclosure, discrete gate or transistor logic, discrete hardware components, or any combination thereof.

[0186] The TRP timeslot allocation manager 1115 or its subcomponents may be physically located at various locations, including being distributed so that portions of functionality are implemented by one or more physical components at different physical locations. In some examples, according to various aspects of the present disclosure, the TRP timeslot allocation manager 1115 or its subcomponents may be separate and distinct components. In some examples, according to various aspects of the present disclosure, the TRP timeslot allocation manager 1115 or its subcomponents may be combined with one or more other hardware components (including but not limited to I / O components, a transceiver, a network server, another computing device, one or more other components described in the present disclosure, or a combination thereof).

[0187] The transmitter 1120 may transmit signals generated by other components of the device 1105. In some examples, the transmitter 1120 may be co-located with the receiver 1110 in a transceiver module. For example, the transmitter 1120 may be a reference Fig.14 Examples of various aspects of the transceiver 1420 are described. The transmitter 1120 may utilize a single antenna or a collection of antennas.

[0188] Fig.12 A block diagram 1200 of a device 1205 supporting an ACK codebook design for multiple TRPs according to aspects of the present disclosure is shown. The device 1205 may be an example of aspects of the device 1105 or base station 105 as described herein. The device 1205 may include a receiver 1210, a TRP timeslot allocation manager 1215, and a transmitter 1245. The device 1205 may also include a processor. Each of these components may be in communication with each other (e.g., via one or more buses).

[0189] Receiver 1210 may receive information such as packets, user data, or control information associated with various information channels (e.g., control channels, data channels, and information related to ACK codebook design for multiple TRPs, etc.). The information may be passed to other components of device 1205. Receiver 1210 may be a reference Fig.14 Examples of various aspects of the transceiver 1420 are described. The receiver 1210 may utilize a single antenna or a collection of antennas.

[0190] The TRP timeslot allocation manager 1215 may be an example of aspects of the TRP timeslot allocation manager 1115 described herein. The TRP timeslot allocation manager 1215 may include a TRP timeslot allocation component 1220, a timeslot allocation transmitter 1225, a downlink message transmitter 1230, a HARQ-ACK feedback indicator 1235, and a feedback receiver 1240. The TRP timeslot allocation manager 1215 may be an example of aspects of the TRP timeslot allocation manager 1410 described herein.

[0191] The TRP timeslot allocation component 1220 may identify, at a TRP, a timeslot allocation for at least one timeslot to be used by the UE to provide HARQ-ACK feedback to the TRP.

[0192] The timeslot allocation transmitter 1225 may transmit the timeslot allocation to one or more other TRPs in communication with the UE to facilitate timeslot allocation coordination between the TRP and the one or more other TRPs.

[0193] The downlink message transmitter 1230 may transmit a downlink message to the UE.

[0194] The HARQ-ACK feedback indicator 1235 may convey an indication that the UE will use the at least one timeslot identified by the timeslot assignment to provide HARQ-ACK feedback.

[0195] Feedback receiver 1240 may receive HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot assignment.

[0196] The transmitter 1245 can transmit signals generated by other components of the device 1205. In some examples, the transmitter 1245 can be co-located with the receiver 1210 in a transceiver module. For example, the transmitter 1245 can be a reference Fig.14 Examples of various aspects of the transceiver 1420 are described. The transmitter 1245 may utilize a single antenna or a collection of antennas.

[0197] Fig.13 A block diagram 1300 of a TRP slot allocation manager 1305 supporting ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is shown. The TRP slot allocation manager 1305 may be an example of aspects of the TRP slot allocation manager 1115, the TRP slot allocation manager 1215, or the TRP slot allocation manager 1410 described herein. The TRP slot allocation manager 1305 may include a TRP slot allocation component 1310, a slot allocation transmitter 1315, a downlink message transmitter 1320, a HARQ-ACK feedback indicator 1325, a feedback receiver 1330, a DCI transmitter 1335, a TRP-specific parameter component 1340, an uplink information receiver 1345, and an uplink parameter transmitter 1350. Each of these modules may communicate directly or indirectly with each other (e.g., via one or more buses).

[0198] The TRP timeslot allocation component 1310 may identify, at a TRP, a timeslot allocation for at least one timeslot to be used by the UE to provide HARQ-ACK feedback to the TRP. In some examples, the TRP timeslot allocation component 1310 may receive, from one or more other TRPs, an additional timeslot allocation identifying a timeslot to be used by the UE to provide HARQ-ACK feedback to the one or more other TRPs, wherein each timeslot identified in the timeslot allocation and the additional timeslot allocation is allocated for feedback transmission by the UE to only one TRP. In some cases, the timeslots may be allocated asymmetrically between the TRP and the additional TRPs.

[0199] The timeslot allocation transmitter 1315 may transmit the timeslot allocation to one or more other TRPs in communication with the UE to facilitate timeslot allocation coordination between the TRP and the one or more other TRPs. In some examples, the timeslot allocation transmitter 1315 may transmit the timeslot allocation via RRC signaling.

[0200] The downlink message transmitter 1320 may transmit a downlink message to the UE. In some examples, the downlink message transmitter 1320 may transmit only one PDSCH per slot from the TRP with a time domain resource allocation having the same ending OFDM symbol.

[0201] The HARQ-ACK feedback indicator 1325 may convey an indication that the UE will use the at least one timeslot identified by the timeslot assignment to provide HARQ-ACK feedback.

[0202] Feedback receiver 1330 may receive HARQ-ACK feedback related to the downlink message from the UE on the at least one time slot identified by the time slot assignment. In some cases, the HARQ-ACK feedback received from the UE in the at least one time slot may include feedback information related to only one PDSCH in multiple time domain resource assignments with the same end OFDM codeword.

[0203] In some examples, the feedback receiver 330 may receive HARQ-ACK feedback on at least one time slot identified by the time slot allocation only if the at least one time slot is identified as an uplink time slot by the cell-specific uplink-downlink configuration associated with the TRP. Additionally or alternatively, the feedback receiver 1330 may receive HARQ-ACK feedback on symbols of at least one time slot identified by the time slot allocation only if the symbols of the at least one time slot are allocated for uplink transmission by the cell-specific uplink-downlink configuration associated with the TRP. In some cases, the feedback receiver 1330 may receive the HARQ-ACK feedback via at least one of the following: via PUCCH, or via PUSCH as piggybacked UCI.

[0204] The DCI transmitter 1335 may transmit the indication via a DCI message. In some examples, the DCI transmitter 335 may transmit a DCI message including an indication of the size of the HARQ-ACK codebook to be used by the UE when providing feedback to the TRP.

[0205] The TRP-specific parameter component 1340 may transmit at least one semi-static TRP-specific parameter to the UE. In some cases, the at least one TRP-specific parameter may include one or more of the following: the number of cells for CA supported by the TRP, the cell-specific uplink-downlink configuration associated with the cells of the TRP, a per-BWP table of time domain resource allocation for the PDSCH for the TRP, a per-BWP parameter set defining the PDSCH-to-feedback timing for the TRP, or a per-BWP PDSCH repetition factor for the TRP.

[0206] The uplink information receiver 1345 may receive additional information from the UE using at least one time slot identified by the time slot allocation. In some cases, the additional information may be in the form of: PUSCH payload, SR or CSI report. Additionally, the HARQ-ACK feedback is combined with the additional information on a single uplink channel.

[0207] The uplink parameter transmitter 1350 may transmit TRP-specific QCL information to the UE. Additionally or alternatively, the uplink parameter transmitter 1350 may transmit TRP-specific power control parameters to the UE for transmissions to the TRP during at least one time slot. Additionally or alternatively, the uplink parameter transmitter 1350 may transmit TRP-specific TA parameters to the UE for transmissions to the TRP during at least one time slot.

[0208] Fig.14 A diagram of a system 1400 including a device 1405 supporting an ACK codebook design for multiple TRPs in accordance with aspects of the present disclosure is shown. The device 1405 may be an example of or include components of a device 1105, a device 1205, or a base station 105 as described herein. The device 1405 may include components for two-way voice and data communications, including components for transmitting and receiving communications, including a TRP timeslot allocation manager 1410, a network communications manager 1415, a transceiver 1420, an antenna 1425, a memory 1430, a processor 1440, and an inter-station communications manager 1445. These components may be in electronic communication via one or more buses (e.g., a bus 1450).

[0209] The TRP timeslot allocation manager 1410 may identify, at the TRP, a timeslot allocation for at least one timeslot to be used by the UE to provide HARQ-ACK feedback to the TRP. The TRP timeslot allocation manager 1410 may then transmit a downlink message to the UE. Additionally, the TRP timeslot allocation manager 1410 may transmit an indication that the UE will use the at least one timeslot identified by the timeslot allocation to provide HARQ-ACK feedback. In some cases, the TRP timeslot allocation manager 1410 may receive HARQ-ACK feedback related to the downlink message from the UE on the at least one timeslot identified by the timeslot allocation.

[0210] The network communications manager 1415 may manage communications with the core network (eg, via one or more wired backhaul links). For example, the network communications manager 1415 may manage the delivery of data communications for client devices, such as one or more UEs 115.

[0211] The transceiver 1420 may communicate bidirectionally via one or more antennas, wired or wireless links, as described herein. For example, the transceiver 1420 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 1420 may also include a modem to modulate packets and provide the modulated packets to an antenna for transmission, and demodulate packets received from an antenna.

[0212] In some cases, a wireless device may include a single antenna 1425. However, in some cases, the device may have more than one antenna 1425, which may be capable of transmitting or receiving multiple wireless transmissions concurrently.

[0213] Memory 1430 may include RAM, ROM, or a combination thereof. Memory 1430 may store computer readable code 1435 including instructions that, when executed by a processor (e.g., processor 1440), cause the device to perform various functions described herein. In some cases, memory 1430 may include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0214] Processor 1440 may include an intelligent hardware device (e.g., a general purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a PLD, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, processor 1440 may be configured to operate a memory array using a memory controller. In some cases, the memory controller may be integrated into processor 1440. Processor 1440 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1430) to cause device 1405 to perform various functions (e.g., functions or tasks supporting ACK codebook design for multiple TRPs).

[0215] The inter-site communication manager 1445 may manage communications with other base stations 105 and may include a controller or scheduler for controlling communications with UE 115 in cooperation with other base stations 105. For example, the inter-site communication manager 1445 may coordinate the scheduling of transmissions to UE 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-site communication manager 1445 may provide an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between base stations 105.

[0216] The code 1435 may include instructions for implementing various aspects of the present disclosure, including instructions for supporting wireless communications. The code 1435 may be stored in a non-transitory computer-readable medium, such as a system memory or other type of memory. In some cases, the code 1435 may not be directly executed by the processor 1440, but may cause a computer (e.g., when compiled and executed) to perform the functions described herein.

[0217] Fig.15 1 is a flow chart illustrating a method 1500 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 1500 may be implemented by the UE 115 or components thereof as described herein. For example, the operations of the method 1500 may be implemented by referring to Figures 7 to 10 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the functions described herein.

[0218] At 1505, the UE may receive a time slot assignment for the UE to provide HARQ-ACK feedback to a set of TRPs. The operations of 1505 may be performed according to the methods described herein. In some examples, aspects of the operations of 1505 may be performed as described with reference to Figures 7 to 10 The described time slot allocation receiver is performed.

[0219] At 1510, the UE may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation. The operations of 1510 may be performed according to the methods described herein. In some examples, aspects of the operations of 1510 may be as described with reference to Figures 7 to 10 The HARQ-ACK codebook component described above is used to perform

[0220] At 1515, the UE may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The operations of 1515 may be performed according to the methods described herein. In some examples, aspects of the operations of 1515 may be as described with reference to Figures 7 to 10 The uplink parameter components described are performed.

[0221] At 1520, the UE may use the corresponding time slot identified by the time slot assignment and transmit feedback to the TRP using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. The operations of 1520 may be performed according to the methods described herein. In some examples, aspects of the operations of 1520 may be as described with reference to Figures 7 to 10 The feedback transmitter described is implemented.

[0222] Fig.16 1 is a flow chart illustrating a method 1600 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 1600 may be implemented by a UE 115 or components thereof as described herein. For example, the operations of the method 1600 may be implemented by reference to Figures 7 to 10 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the functions described herein.

[0223] At 1605, the UE may receive a time slot assignment for the UE to provide HARQ-ACK feedback to a set of TRPs. The operations of 1605 may be performed according to the methods described herein. In some examples, aspects of the operations of 1605 may be as described with reference to Figures 7 to 10 The described time slot allocation receiver is performed.

[0224] At 1610, the UE may receive an allocation of time slots to be used by the UE to provide HARQ-ACK feedback to different TRPs in the set of TRPs, wherein each time slot identified in the time slot allocation is allocated for feedback transmission by the UE to only one TRP in the set of TRPs. The operations of 1610 may be performed according to the methods described herein. In some examples, aspects of the operations of 1610 may be performed as described with reference to Figures 7 to 10 The described time slot allocation receiver is performed.

[0225] At 1615, the UE may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation. The operations of 1615 may be performed according to the methods described herein. In some examples, aspects of the operations of 1615 may be as described with reference to Figures 7 to 10 The HARQ-ACK codebook component described above is used to perform

[0226] At 1620, the UE may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The operations of 1620 may be performed according to the methods described herein. In some examples, aspects of the operations of 1620 may be as described with reference to Figures 7 to 10 The uplink parameter components described are performed.

[0227] At 1625, the UE may use the corresponding time slot identified by the time slot allocation and transmit feedback to the TRP using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. The operations of 1625 may be performed according to the methods described herein. In some examples, aspects of the operations of 1625 may be as described with reference to Figures 7 to 10 The feedback transmitter described is implemented.

[0228] Fig.17 1 is a flow chart illustrating a method 1700 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 1700 may be implemented by a UE 115 or components thereof as described herein. For example, the operations of the method 1700 may be implemented by reference to Figures 7 to 10 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the functions described herein.

[0229] At 1705, the UE may receive a time slot assignment for the UE to provide HARQ-ACK feedback to a set of TRPs. The operations of 1705 may be performed according to the methods described herein. In some examples, aspects of the operations of 1705 may be performed as described with reference to Figures 7 to 10 The described time slot allocation receiver is performed.

[0230] At 1710, the UE may receive a DCI message including an indication of the size of the HARQ-ACK codebook. The operations of 1710 may be performed according to the methods described herein. In some examples, aspects of the operations of 1710 may be performed as described with reference to Figures 7 to 10 The DCI components described are performed.

[0231] At 1715, the UE may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation. The operations of 1715 may be performed according to the methods described herein. In some examples, aspects of the operations of 1715 may be as described with reference to Figures 7 to 10 The HARQ-ACK codebook component described above is used to perform

[0232] At 1720, the UE may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The operations of 1720 may be performed according to the methods described herein. In some examples, aspects of the operations of 1720 may be as described with reference to Figures 7 to 10 The uplink parameter components described are performed.

[0233] At 1725, the UE may use the corresponding time slot identified by the time slot allocation and transmit feedback to the TRP using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. The operations of 1725 may be performed according to the methods described herein. In some examples, aspects of the operations of 1725 may be as described with reference to Figures 7 to 10 The feedback transmitter described is implemented.

[0234] Fig.18 1 is a flow chart illustrating a method 1800 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 1800 may be implemented by a UE 115 or components thereof as described herein. For example, the operations of the method 1800 may be implemented by reference to Figures 7 to 10 In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the functions described herein. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the functions described herein.

[0235] At 1805, the UE may receive a time slot assignment for the UE to provide HARQ-ACK feedback to a set of TRPs. The operations of 1805 may be performed according to the methods described herein. In some examples, aspects of the operations of 1805 may be performed as described with reference to Figures 7 to 10The described time slot allocation receiver is performed.

[0236] At 1810, the UE may determine a TRP-specific HARQ-ACK codebook based on at least one TRP-specific parameter received semi-statically. The operations of 1810 may be performed according to the methods described herein. In some examples, aspects of the operations of 1810 may be as described with reference to Figures 7 to 10 The described semi-static HARQ-ACK codebook component is performed.

[0237] At 1815, the UE may determine a TRP-specific HARQ-ACK codebook for feedback transmission to a TRP in the set of TRPs based on the time slot allocation. The operations of 1815 may be performed according to the methods described herein. In some examples, aspects of the operations of 1815 may be as described with reference to Figures 7 to 10 The HARQ-ACK codebook component described above is used to perform

[0238] At 1820, the UE may determine one or more TRP-specific uplink parameters for feedback transmission to the TRP. The operations of 1820 may be performed according to the methods described herein. In some examples, aspects of the operations of 1820 may be as described with reference to Figures 7 to 10 The uplink parameter components described are performed.

[0239] At 1825, the UE may use the corresponding time slot identified by the time slot allocation and transmit feedback to the TRP using the TRP-specific HARQ-ACK codebook and the one or more TRP-specific uplink parameters. The operations of 1825 may be performed according to the methods described herein. In some examples, aspects of the operations of 1825 may be as described with reference to Figures 7 to 10 The feedback transmitter described is implemented.

[0240] Fig.19 1 is a flow chart illustrating a method 1900 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 1900 may be implemented by a base station 105 or components thereof as described herein. For example, the operations of the method 1900 may be implemented by reference to Figures 11 to 14 In some examples, the base station may execute an instruction set to control the functional elements of the base station to perform the functions described herein. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the functions described herein.

[0241] At 1905, the base station may identify, at the TRP, a time slot allocation for at least one time slot to be used by the UE to provide HARQ-ACK feedback to the TRP. The operations of 1905 may be performed according to the methods described herein. In some examples, aspects of the operations of 1905 may be as described with reference to Figures 11 to 14 The TRP timeslot allocation component described is performed.

[0242] At 1910, the base station may transmit the time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the TRP and the one or more other TRPs. The operations of 1910 may be performed according to the methods described herein. In some examples, aspects of the operations of 1910 may be performed as described with reference to Figures 11 to 14 The described time slot allocation is performed by the transmitter.

[0243] At 1915, the base station may transmit a downlink message to the UE. The operations of 1915 may be performed according to the methods described herein. In some examples, aspects of the operations of 1915 may be performed as described with reference to Figures 11 to 14 The described downlink message transmitter is performed.

[0244] At 1920, the base station may transmit an indication that the UE will use the at least one time slot identified by the time slot allocation to provide HARQ-ACK feedback. The operations of 1920 may be performed according to the methods described herein. In some examples, aspects of the operations of 1920 may be performed as described with reference to Figures 11 to 14 The HARQ-ACK feedback indicator described is performed.

[0245] At 1925, the base station may receive HARQ-ACK feedback related to the downlink message from the UE on the at least one time slot identified by the time slot assignment. The operations of 1925 may be performed according to the methods described herein. In some examples, aspects of the operations of 1925 may be performed as described with reference to Figures 11 to 14 The feedback receiver described is implemented.

[0246] Fig. 20 1 is a flow chart illustrating a method 2000 for supporting ACK codebook design for multiple TRPs according to aspects of the present disclosure. The operations of the method 2000 may be implemented by a base station 105 or components thereof as described herein. For example, the operations of the method 2000 may be implemented by reference to Figures 11 to 14 In some examples, the base station may execute an instruction set to control the functional elements of the base station to perform the functions described herein. Additionally or alternatively, the base station may use dedicated hardware to perform various aspects of the functions described herein.

[0247] At 2005, the base station may identify, at the TRP, a time slot allocation for at least one time slot to be used by the UE to provide HARQ-ACK feedback to the TRP. The operations of 2005 may be performed according to the methods described herein. In some examples, aspects of the operations of 2005 may be performed as described with reference to Figures 11 to 14 The TRP timeslot allocation component described is performed.

[0248] At 2010, the base station may receive, from one or more other TRPs, an additional time slot allocation identifying time slots to be used by the UE to provide HARQ-ACK feedback to the one or more other TRPs, wherein each time slot identified in the time slot allocation and the additional time slot allocation is allocated for feedback transmission by the UE to only one TRP. The operations of 2010 may be performed according to the methods described herein. In some examples, aspects of the operations of 2010 may be performed as described with reference to Figures 11 to 14 The TRP timeslot allocation component described is performed.

[0249] At 2015, the base station may transmit the time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the TRP and the one or more other TRPs. The operations of 2015 may be performed according to the methods described herein. In some examples, aspects of the operations of 2015 may be performed as described with reference to Figures 11 to 14 The described time slot allocation is performed by the transmitter.

[0250] At 2020, the base station may transmit a downlink message to the UE. The operations of 2020 may be performed according to the methods described herein. In some examples, aspects of the operations of 2020 may be performed as described with reference to Figures 11 to 14 The described downlink message transmitter is performed.

[0251] At 2025, the base station may transmit an indication that the UE will use the at least one time slot identified by the time slot allocation to provide HARQ-ACK feedback. The operations of 2025 may be performed according to the methods described herein. In some examples, aspects of the operations of 2025 may be performed as described with reference to Figures 11 to 14 The HARQ-ACK feedback indicator described is performed.

[0252] At 2030, the base station may receive HARQ-ACK feedback related to the downlink message from the UE on the at least one time slot identified by the time slot allocation. The operations of 2030 may be performed according to the methods described herein. In some examples, aspects of the operations of 2030 may be performed as described with reference to Figures 11 to 14 The feedback receiver described is implemented.

[0253] It should be noted that the methods described herein describe possible implementations, and that the various operations and steps may be rearranged or otherwise modified and other implementations are possible. Furthermore, aspects from two or more methods may be combined.

[0254] The technology described herein can be used in various wireless communication systems, such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), single carrier frequency division multiple access (SC-FDMA) and other systems. CDMA systems can implement radio technologies such as CDMA2000, Universal Terrestrial Radio Access (UTRA). CDMA2000 covers IS-2000, IS-95 and IS-856 standards. IS-2000 versions are generally referred to as CDMA2000 1X, 1X, etc. IS-856 (TIA-856) is generally referred to as CDMA2000 1xEV-DO, High Rate Packet Data (HRPD), etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. TDMA systems can implement radio technologies such as Global System for Mobile Communications (GSM).

[0255] OFDMA systems can implement radio technologies such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunications System (UMTS). LTE, LTE-A, and LTE-A Pro are versions of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, LTE-A Pro, NR, and GSM are described in documents from an organization named "3rd Generation Partnership Project" (3GPP). CDMA2000 and UMB are described in documents from an organization named "3rd Generation Partnership Project 2" (3GPP2). The techniques described herein may be used for systems and radio technologies mentioned herein as well as for other systems and radio technologies. Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein may also be applicable to applications other than LTE, LTE-A, LTE-A Pro, or NR applications.

[0256] A macro cell generally covers a relatively large geographic area (e.g., an area of ​​several kilometers in radius) and may allow unrestricted access by UEs 115 that have service subscriptions with a network provider. A small cell may be associated with a lower power base station 105 (compared to a macro cell), and the small cell may operate in the same or different (e.g., licensed, unlicensed, etc.) frequency band as the macro cell. According to various examples, a small cell may include a pico cell, a femto cell, and a micro cell. A pico cell, for example, may cover a smaller geographic area and may allow unrestricted access by UEs 115 that have service subscriptions with a network provider. A femto cell may also cover a smaller geographic area (e.g., a residence) and may provide restricted access by UEs 115 associated with the femto cell (e.g., UEs 115 in a closed subscriber group (CSG), UEs 115 of users in a residence, etc.). An eNB for a macro cell may be referred to as a macro eNB. An eNB for a small cell may be referred to as a small cell eNB, a pico eNB, a femto eNB, or a home eNB. An eNB may support one or more (eg, two, three, four, etc.) cells and may also support communication using one or more component carriers.

[0257] One or more wireless communication systems 100 described herein may support synchronous or asynchronous operation. For synchronous operation, the base stations 105 may have similar frame timing, and transmissions from different base stations 105 may be approximately aligned in time. For asynchronous operation, the base stations 105 may have different frame timing, and transmissions from different base stations 105 may not be aligned in time. The techniques described herein may be used for synchronous or asynchronous operation.

[0258] The information and signals described herein may be represented using any of a variety of different techniques and technologies. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referred to throughout this description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0259] The various illustrative blocks and modules described in conjunction with the disclosure herein may be implemented or executed with a general purpose processor, a DSP, an ASIC, an FPGA or other PLD, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0260] The functions described herein may be implemented in hardware, software executed by a processor, firmware, or any combination thereof. If implemented in software executed by a processor, the functions may be stored on or transmitted by a computer-readable medium as one or more instructions or codes. Other examples and implementations fall within the scope of this disclosure and the appended claims. For example, due to the nature of software, the functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or any combination thereof. Features that implement the functions may also be physically located in various locations, including being distributed so that parts of the functions are implemented at different physical locations.

[0261] Computer readable medium includes both non-transient computer storage medium and communication medium, and it includes any medium that facilitates computer program to transfer from one place to another place.Non-transient storage medium can be any available medium that can be accessed by general or special-purpose computer.As an example and not limitation, non-transient computer readable medium can include RAM, ROM, electrically erasable programmable read-only memory (EEPROM), flash memory, compact disk (CD) ROM or other optical disk storage, disk storage or other magnetic storage device, or can be used to carry or store instruction or data structure form of desired program code means and can be accessed by general or special-purpose computer or general or special-purpose processor any other non-transient medium.Any connection is also properly referred to as computer readable medium.For example, if software is transmitted from website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology such as infrared, radio and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are just included in the definition of medium. Disk and disc as used herein include CDs, laser discs, optical discs, digital versatile discs (DVDs), floppy disks, and Blu-ray discs, where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above are also included within the scope of computer-readable media.

[0262] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items with a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). Similarly, as used herein, the phrase "based on" should not be interpreted as referring to a closed set of conditions. For example, an exemplary step described as "based on condition A" may be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on."

[0263] In the accompanying drawings, similar components or features may have the same reference number. In addition, various components of the same type may be distinguished by following the reference number with a dash and a second reference number that distinguishes between similar components. If only the first reference number is used in the specification, the description may apply to any of the similar components having the same first reference number regardless of the second reference number, or other subsequent reference numbers.

[0264] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or that fall within the scope of the claims. The term "exemplary" as used herein means "used as an example, instance, or illustration" and does not mean "better than" or "better than other examples." This detailed description includes specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0265] The description herein is provided to enable those skilled in the art to make or use the present disclosure. Various modifications to the present disclosure will be apparent to those skilled in the art, and the universal principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for wireless communication at a user equipment (UE), comprising: Receiving, from a network device, a combined timeslot allocation for a physical uplink control channel (PUCCH) transmission to a different one of a plurality of transmit-receive points (TRPs) associated with the network device, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmission to a first TRP in the plurality of TRPs, and a second time slot allocated for PUCCH transmission to a second TRP in the plurality of TRPs, and wherein each time slot identified in the combined time slot allocation is allocated for a PUCCH transmission by the UE to only one TRP of the plurality of TRPs; as well as A hybrid automatic repeat request (HARQ) acknowledgment feedback is transmitted to the first TRP using the first time slot assigned for PUCCH transmission to the first TRP identified by the combined time slot allocation and using one or more TRP-specific uplink parameters.

2. The method of claim 1 , wherein receiving the combined time slot assignment comprises: Receiving, from the network device, a request to a different TRP among the plurality of TRPs Combined time slot allocation for PUCCH transmission, wherein the time slots are allocated asymmetrically among the multiple TRPs.

3. The method of claim 1, further comprising: A TRP-specific HARQ acknowledgment codebook is determined based at least in part on at least one TRP-specific parameter received semi-statically.

4. The method of claim 3, wherein the at least one TRP-specific parameter is one or more of the number of cells supported by the TRP for carrier aggregation, a cell-specific uplink-downlink configuration associated with the cells of the TRP, a per-bandwidth part table of time domain resource allocation for a physical downlink shared channel of the TRP, a per-bandwidth part parameter set defining a physical downlink shared channel to feedback timing for the TRP, or a per-bandwidth part physical downlink shared channel repetition factor for the TRP.

5. The method of claim 1, further comprising: for time domain resource allocations overlapping in time, identifying only one physical downlink shared channel reception opportunity from the first TRP per cell per time slot; as well as A physical downlink shared channel transmission associated with the identified physical downlink shared channel reception opportunity is received from the first TRP, wherein the HARQ acknowledgment feedback transmitted in the first time slot includes feedback information relating to the one physical downlink shared channel reception opportunity or the one physical downlink shared channel transmission.

6. The method of claim 5, further comprising: receiving an additional physical downlink shared channel transmission from the second TRP, the additional physical downlink shared channel transmission having a time domain resource allocation overlapping with the one physical downlink shared channel transmission received from the first TRP in the same component carrier; as well as A second HARQ acknowledgment feedback is transmitted to the second TRP in the second time slot allocated for PUCCH transmission to the second TRP as identified by the combined time slot allocation.

7. The method of claim 1, further comprising: The combined time slot allocation is compared with a cell-specific uplink-downlink configuration associated with the cell of the first TRP, wherein the HARQ acknowledgment feedback is transmitted to the first TRP using the first time slot only if the code elements of the first time slot are also allocated for uplink transmission by the cell-specific uplink-downlink configuration.

8. The method of claim 1, further comprising: Use the first time slot identified by the combined time slot allocation to transmit additional information to the first TRP.

9. The method of claim 8, wherein the additional information is in the form of a physical uplink shared channel payload, a scheduling request, or a channel state information report, and wherein the HARQ acknowledgment feedback is combined with the additional information on a single uplink channel.

10. The method of claim 1, wherein transmitting the HARQ acknowledgment feedback to the first TRP using the first time slot comprises: The HARQ acknowledgement feedback is transmitted via at least one of: a physical uplink control channel, or via a physical uplink shared channel as piggybacked uplink control information.

11. The method of claim 1, further comprising: determining the one or more TRP-specific uplink parameters, wherein the one or more TRP-specific uplink parameters are for a PUCCH transmission to the first TRP, and The determination includes: An identification configures quasi-co-location (QCL) information for physical uplink control channel transmission; and Identify TRP-specific QCL information for the first TRP for the first time slot.

12. The method of claim 1, further comprising: determining the one or more TRP-specific uplink parameters, wherein the one or more TRP-specific uplink parameters are for a PUCCH transmission to the first TRP, and The determination includes: The reason for the first time slot identification for transmission to the first TRP Power control parameters that vary depending on TRP.

13. The method of claim 12, wherein the TRP-dependent power control parameter comprises at least one of an open-loop power control parameter and a closed-loop power control parameter.

14. The method of claim 1, further comprising: determining the one or more TRP-specific uplink parameters, wherein the one or more TRP-specific uplink parameters are for a PUCCH transmission to the first TRP, and The determination includes: The reason for the first time slot identification for transmission to the first TRP TRP varies depending on the timing advance parameter.

15. The method of claim 1 , wherein receiving the combined time slot assignment comprises: The combined timeslot allocation is received via radio resource control (RRC) signaling.

16. The method of claim 1, further comprising: Determining to transmit a plurality of HARQ acknowledgment feedback messages to the first TRP; Based at least in part on the combined time slot allocation, a plurality of time slots are identified to allocate to the first The TRP transmits the multiple HARQ confirmation feedback messages; as well as The multiple HARQ confirmation feedback messages are transmitted to the first TRP in the identified multiple time slots.

17. A method as claimed in claim 16, wherein the multiple time slots include time slots allocated only to the first TRP, several consecutive time slots allocated to any TRP among the multiple TRPs, several consecutive time slots allocated to the first TRP, or a combination thereof.

18. A method for wireless communication at a first transmit-receive point (TRP) of a plurality of transmit-receive points (TRPs) associated with a network device, comprising: identifying, at the first TRP, a combined timeslot allocation of at least one timeslot to be used by a user equipment (UE) for physical uplink control channel (PUCCH) transmissions to a different TRP in the plurality of TRPs, the plurality of TRPs further comprising a second TRP, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmissions to the first TRP, and a second time slot allocated for PUCCH transmissions to the second TRP, and wherein each time slot identified in the combined time slot allocation is allocated for PUCCH transmissions by the UE to only one of the multiple TRPs; transmitting a downlink message to the UE; transmitting an indication that the UE is to provide PUCCH transmissions for each of the different TRPs using the at least one timeslot identified by the combined timeslot allocation for the different TRPs; as well as A hybrid automatic repeat request (HARQ) acknowledgment feedback related to the downlink message is received from the UE and on the first time slot allocated for PUCCH transmission to the first TRP as identified by the combined time slot allocation.

19. The method of claim 18, further comprising: transmitting the combined time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the first TRP and the one or more other TRPs; receiving, from the one or more other TRPs, an additional time slot allocation identifying time slots to be used by the UE for PUCCH transmissions to the one or more other TRPs, wherein each time slot identified in the combined time slot allocation and the additional time slot allocation is an allocation for PUCCH transmissions by the UE to only one TRP; or a combination thereof.

20. The method of claim 18, wherein the time slots in the combined time slot allocation are allocated asymmetrically among the multiple TRPs.

21. The method of claim 18, wherein transmitting the indication comprises: The indication is transmitted via a downlink control information message.

22. The method of claim 18, further comprising: At least one semi-static TRP-specific parameter is transmitted to the UE.

23. A method as claimed in claim 22, wherein the at least one semi-static TRP-specific parameter is one or more of the number of cellular cells supported by the first TRP for carrier aggregation, the cellular cell-specific uplink-downlink configuration associated with the cellular cells of the first TRP, a per-bandwidth part table of time domain resource allocation for the physical downlink shared channel of the first TRP, a per-bandwidth part parameter set defining the physical downlink shared channel to feedback timing for the first TRP, or a physical downlink shared channel repetition factor per bandwidth part for the first TRP.

24. The method of claim 18, wherein receiving the HARQ acknowledgment feedback related to the downlink message comprises: The HARQ confirmation feedback is received on the first time slot only if the first time slot identified by the combined time slot allocation is identified as an uplink time slot by the cell-specific uplink-downlink configuration associated with the first TRP.

25. The method of claim 18, wherein receiving the HARQ acknowledgment feedback related to the downlink message comprises: The HARQ confirmation feedback is received on a codeword of the first time slot only if the codeword of the first time slot identified by the combined time slot allocation is allocated for uplink transmission by the cell-specific uplink-downlink configuration associated with the first TRP.

26. The method of claim 18, further comprising: Additional information is received from the UE using the first time slot identified by the combined time slot assignment.

27. The method of claim 26, wherein the additional information is in the form of a physical uplink shared channel payload, a scheduling request, or a channel state information report, and wherein the HARQ acknowledgment feedback related to the downlink message is combined with the additional information on a single uplink channel.

28. The method of claim 18, wherein receiving the HARQ acknowledgment feedback related to the downlink message comprises: The HARQ acknowledgement feedback is received via at least one of: a physical uplink control channel, or via a physical uplink shared channel as piggybacked uplink control information.

29. The method of claim 18, further comprising: Transmit quasi-collocation (QCL) information that varies depending on the TRP to the UE.

30. The method of claim 18, further comprising: Transmitting to the UE TRP-specific power control parameters for transmissions to the first TRP during the first time slot.

31. The method of claim 18, further comprising: Transmitting to the UE a TRP-specific timing advance parameter for transmission to the first TRP during the first time slot.

32. The method of claim 18, further comprising: The combined timeslot allocation is communicated via radio resource control (RRC) signaling.

33. An apparatus for wireless communication at a user equipment (UE), comprising: processor; a memory coupled to the processor; as well as instructions stored in the memory and executable by the processor to cause the apparatus to: Receiving, from a network device, a combined timeslot allocation for a physical uplink control channel (PUCCH) transmission to a different one of a plurality of transmit-receive points (TRPs) associated with the network device, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmission to a first TRP in the plurality of TRPs, and a second time slot allocated for PUCCH transmission to a second TRP in the plurality of TRPs, and wherein each time slot identified in the combined time slot allocation is allocated for a PUCCH transmission by the UE to only one TRP of the plurality of TRPs; as well as The combined timeslot assignment identifier is used to identify the first TRP. The first time slot allocated for PUCCH transmission and using one or more TRP-specific uplink parameters to transmit hybrid automatic repeat request (HARQ) confirmation feedback to the first TRP.

34. The apparatus of claim 33, wherein the instructions for receiving the combined time slot assignment are executable by the processor to cause the apparatus to: Receive combined time slot allocations for PUCCH transmissions to different TRPs among the multiple TRPs, wherein the time slots are allocated asymmetrically between the multiple TRPs.

35. The apparatus of claim 33, wherein the instructions are further executable by the processor to cause the apparatus to: A TRP-specific HARQ acknowledgment codebook is determined based at least in part on at least one TRP-specific parameter received semi-statically.

36. The apparatus of claim 33, wherein the instructions are further executable by the processor to cause the apparatus to: For time domain resource allocations that overlap in time, identifying only one physical downlink shared channel reception opportunity from the first TRP per cell per time slot; and A physical downlink shared channel transmission associated with the identified physical downlink shared channel receiver opportunity is received from the first TRP, wherein the HARQ acknowledgment feedback transmitted in the first time slot includes feedback information related to the one physical downlink announcement to the channel receiver opportunity or the one physical downlink shared channel transmission.

37. The apparatus of claim 36, wherein the instructions are further executable by the processor to cause the apparatus to: receiving an additional physical downlink shared channel transmission from the second TRP, the additional physical downlink shared channel transmission having a time domain resource allocation overlapping with the one physical downlink shared channel transmission received from the first TRP in the same component carrier; and A second HARQ acknowledgment feedback is transmitted to the second TRP in the second time slot allocated for PUCCH transmission to the second TRP as identified by the combined time slot allocation.

38. The apparatus of claim 33, wherein instructions for transmitting HARQ acknowledgment feedback to the first TRP using the first time slot are executable by the processor to cause the apparatus to: The HARQ acknowledgement feedback is transmitted via at least one of: a physical uplink control channel, or via a physical uplink shared channel as piggybacked uplink control information.

39. The apparatus of claim 33, wherein the instructions are further executable by the processor to cause the apparatus to: determining the one or more TRP-specific uplink parameters, wherein the one or more TRP-specific uplink parameters are for a HARQ acknowledgment feedback PUCCH transmission to the first TRP, and wherein the instructions for determining the one or more TRP-specific uplink parameters are executable by the processor to cause the apparatus; The reason for the first time slot identification for transmission to the first TRP Power control parameters that vary depending on TRP.

40. The apparatus of claim 33, wherein the instructions are further executable by the processor to cause the apparatus to: Determining to transmit a plurality of HARQ acknowledgment feedback messages to the first TRP; identifying a plurality of time slots for transmitting the plurality of HARQ acknowledgment feedback messages to the first TRP based at least in part on the combined time slot allocation; as well as The multiple HARQ confirmation feedback messages are transmitted to the first TRP in the identified multiple time slots.

41. An apparatus for wirelessly communicating at a first transmit-receive point (TRP) of a plurality of transmit-receive points (TRPs) associated with a network device, comprising: processor; a memory coupled to the processor; as well as instructions stored in the memory and executable by the processor to cause the apparatus to: identifying, at the first TRP, a combined timeslot allocation of at least one timeslot to be used by a user equipment (UE) for physical uplink control channel (PUCCH) transmissions to a different TRP in the plurality of TRPs, the plurality of TRPs further comprising a second TRP, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmission to the first TRP, and a second time slot allocated for PUCCH transmission to the second TRP, and wherein each time slot identified in the combined time slot allocation is allocated for a PUCCH transmission by the UE to only one TRP of the plurality of TRPs; transmitting a downlink message to the UE; The UE is to use the combined time slots allocated to the different The at least one time slot identified by each of the TRPs is used to provide the different TRPs Indication of PUCCH transmission; as well as A hybrid automatic repeat request (HARQ) acknowledgment feedback related to the downlink message is received from the UE and on the first time slot allocated for PUCCH transmission to the first TRP as identified by the combined time slot allocation.

42. The apparatus of claim 41, wherein the instructions are further executable by the processor to cause the apparatus to: transmitting the combined timeslot allocation to one or more other TRPs in communication with the UE to facilitate timeslot allocation coordination between the first TRP and the one or more other TRPs; and An additional time slot allocation is received from the one or more other TRPs identifying time slots to be used by the UE for PUCCH transmissions to the one or more other TRPs, wherein each time slot identified in the combined time slot allocation and the additional time slot allocation is an allocation for PUCCH transmissions by the UE to only one TRP.

43. An apparatus as claimed in claim 41, wherein the time slots in the combined time slot allocation are allocated asymmetrically among the multiple TRPs.

44. The apparatus of claim 41, wherein the instructions for transmitting the indication are executable by the processor to cause the apparatus to: The indication is transmitted via a downlink control information message.

45. An apparatus for wireless communication at a user equipment (UE), comprising: Means for receiving, from a network device, a combined timeslot allocation for a physical uplink control channel (PUCCH) transmission to a different one of a plurality of transmit-receive points (TRPs) associated with the network device, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmission to a first TRP in the plurality of TRPs, and a second time slot allocated for PUCCH transmission to a second TRP in the plurality of TRPs, and wherein each time slot identified in the combined time slot allocation is allocated for a PUCCH transmission by the UE to only one TRP of the plurality of TRPs; as well as for using the timeslot allocated by the combined timeslot to the first TRP A component for transmitting the first time slot allocated for PUCCH transmission and using one or more uplink parameters that vary depending on the TRP to transmit a hybrid automatic repeat request (HARQ) confirmation feedback to the first TRP.

46. ​​An apparatus for wirelessly communicating at a first transmit-receive point (TRP) of a plurality of transmit-receive points (TRPs) associated with a network device, comprising: means for identifying, at the first TRP, a combined timeslot allocation of at least one timeslot to be used by a user equipment (UE) for physical uplink control channel (PUCCH) transmissions to a different TRP in the plurality of TRPs, the plurality of TRPs further comprising a second TRP, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmissions to the first TRP, and a second time slot allocated for PUCCH transmissions to the second TRP, and wherein each time slot identified in the combined time slot allocation is allocated for PUCCH transmissions by the UE to only one of the multiple TRPs; means for transmitting the combined time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the first TRP and the one or more other TRPs; means for transmitting a downlink message to the UE; means for transmitting an indication that the UE is to use the at least one time slot identified by the combined time slot allocation for each of the different TRPs to provide a PUCCH transmission to the different TRPs; as well as Component for receiving a hybrid automatic repeat request (HARQ) acknowledgment feedback related to the downlink message from the UE and on the first time slot allocated for PUCCH transmission to the first TRP identified by the combined time slot allocation.

47. A non-transitory computer-readable medium storing code for wireless communication at a user equipment (UE), the code comprising instructions executable by a processor to: Receiving, from a network device, a combined timeslot allocation for a physical uplink control channel (PUCCH) transmission to a different one of a plurality of transmit-receive points (TRPs) associated with the network device, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmission to a first TRP in the plurality of TRPs, and a second time slot allocated for PUCCH transmission to a second TRP in the plurality of TRPs, and wherein each time slot identified in the combined time slot allocation is allocated for PUCCH transmission by the UE to only one TRP of the plurality of TRPs; and A hybrid automatic repeat request (HARQ) acknowledgment feedback is transmitted to the first TRP using the first timeslot allocated for PUCCH transmission to the first TRP identified by the combined timeslot allocation and using one or more TRP-specific uplink parameters.

48. A non-transitory computer-readable medium storing code for wirelessly communicating at a first transmit-receive point (TRP) of a plurality of transmit-receive points (TRPs) associated with a network device, the code comprising instructions executable by a processor to: identifying, at the first TRP, a combined timeslot allocation of at least one timeslot to be used by a user equipment (UE) for physical uplink control channel (PUCCH) transmissions to a different TRP in the plurality of TRPs, the plurality of TRPs further comprising a second TRP, wherein the combined timeslot allocation identifies: a first time slot allocated for PUCCH transmissions to the first TRP, and a second time slot allocated for PUCCH transmissions to the second TRP, and wherein each time slot identified in the combined time slot allocation is allocated for PUCCH transmissions by the UE to only one of the multiple TRPs; transmitting the combined time slot allocation to one or more other TRPs in communication with the UE to facilitate time slot allocation coordination between the first TRP and the one or more other TRPs; transmitting a downlink message to the UE; transmitting an indication that the UE is to provide PUCCH transmissions for each of the different TRPs using the at least one timeslot identified by the combined timeslot allocation for the different TRPs; as well as A hybrid automatic repeat request (HARQ) acknowledgment feedback related to the downlink message is received from the UE and on the first time slot allocated for PUCCH transmission to the first TRP as identified by the combined time slot allocation.

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