User terminal method and user terminal

Abstract

The embodiments of the present disclosure relate to a method, an apparatus, and a computer-readable medium for communication. A terminal device receives a first downlink transmission in a first cell of a cell group from a network device, and determines a second cell of a first uplink control transmission for a first hybrid automatic repeat request (HARQ) feedback for the first downlink transmission from a cell set for uplink control transmission associated with the cell group. In this way, the delay of the HARQ feedback can be reduced.

Description

[Technical field]

[0001] FIELD OF THE DISCLOSURE Embodiments of the present disclosure relate generally to the field of telecommunications, and more particularly, to a communication method, apparatus, and computer storage medium for Hybrid Automatic Repeat Request (HARQ) feedback. [Background technology]

[0002] In New Radio (NR) Release 16, for a terminal device configured with Carrier Aggregation (CA), only the uplink (UL) carrier of a component carrier (CC) is configured to transmit a Physical Uplink Control Channel (PUCCH) for HARQ feedback within a cell group, also called a PUCCH group, e.g. a primary cell.

[0003] In NR Release 17, PUCCH carrier switching for HARQ feedback is proposed to reduce HARQ feedback delay for downlink (DL) heavy configurations in unpaired spectrum. This allows multiple UL carriers with different time division duplexing (TDD) settings for PUCCH transmission for HARQ feedback. However, the implementation of PUCCH carrier switching is imperfect and may result in unintended HARQ feedback delay. Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, embodiments of the present disclosure provide a communication method, apparatus, and computer storage medium for HARQ feedback. [Means for solving the problem]

[0005] In a first aspect, a communication method is provided, the method including: receiving, in a terminal device, from a network device, a first downlink transmission at a first cell of a cell group; and determining, from a cell set for uplink control transmission associated with the cell group, a second cell of the first uplink control transmission for a first hybrid automatic repeat request (HARQ) feedback for the first downlink transmission.

[0006] In a second aspect, a communication method is provided, the method including: transmitting, in a network device, to a terminal device, a first downlink transmission in a first cell in a cell group, and receiving, from the terminal device, a first Hybrid Automatic Repeat Request (HARQ) feedback for the first downlink transmission in a second cell, the second cell being determined from a cell set for uplink control transmission associated with the cell group.

[0007] In a third aspect, there is provided a terminal device, the terminal device including a processor configured to execute the method according to the first aspect of the present disclosure.

[0008] In a fourth aspect, there is provided a network device, the network device including a processor configured to perform the method according to the second aspect of the present disclosure.

[0009] In a fifth aspect, there is provided a computer readable medium having stored thereon instructions which, when executed on at least one processor, cause the at least one processor to perform a method according to the first aspect of the present disclosure.

[0010] In a sixth aspect, there is provided a computer readable medium having stored thereon instructions which, when executed on at least one processor, cause the at least one processor to perform a method according to the second aspect of the present disclosure.

[0011] Other features of the present disclosure will become readily apparent from the following description. [Brief description of the drawings]

[0012] The above and other objects, features and advantages of the present disclosure will become more apparent through more detailed description of several embodiments of the present disclosure in the accompanying drawings.

[0013] [Figure 1] 1 illustrates an exemplary communications network in which some embodiments of the present disclosure may be implemented;

[0014] [Figure 2A] FIG. 1 is a schematic diagram illustrating an example scenario of HARQ feedback according to a conventional solution;

[0015] [Figure 2B] FIG. 2 is a schematic diagram illustrating an example scenario of PUCCH carrier switching for HARQ feedback, according to an embodiment of the present disclosure.

[0016] [Figure 3A] 1 is a flowchart illustrating a communication process of HARQ feedback according to an embodiment of the present disclosure.

[0017] [Figure 3B] 13 is a flowchart illustrating another communication process of HARQ feedback in accordance with an embodiment of the present disclosure.

[0018] [Figure 3C] 13 is a flowchart illustrating another communication process of HARQ feedback in accordance with an embodiment of the present disclosure.

[0019] [Figure 3D] 13 is a flowchart illustrating another communication process of HARQ feedback in accordance with an embodiment of the present disclosure.

[0020] [Figure 4] FIG. 2 is a schematic diagram illustrating an example configuration of PUCCH carriers according to an embodiment of the present disclosure.

[0021] [Figure 5A] FIG. 2 is a schematic diagram illustrating an example of PUCCH carrier switching for HARQ-ACK in semi-persistent scheduling (SPS) according to an embodiment of the present disclosure.

[0022] [Figure 5B] FIG. 13 is a schematic diagram illustrating another example of PUCCH carrier switching for SPS HARQ-ACK according to an embodiment of the present disclosure.

[0023] [Figure 6] FIG. 2 is a schematic diagram illustrating an example of an interaction between PUCCH carrier switching for SPS HARQ-ACK and SPS HARQ-ACK postponement according to an embodiment of the present disclosure.

[0024] [Figure 7A] FIG. 2 is a schematic diagram illustrating an example of interaction between PUCCH carrier switching and intra-UE multiplexing or prioritization according to an embodiment of the present disclosure.

[0025] [Figure 7B] FIG. 2 is a schematic diagram illustrating an example scenario of interaction between PUCCH carrier switching and intra-UE multiplexing, according to an embodiment of the present disclosure.

[0026] [Figure 8] 1 illustrates an exemplary communication method implemented in a terminal device according to some embodiments of the present disclosure.

[0027] [Figure 9] 1 illustrates an exemplary communication method implemented in a network device, according to some embodiments of the present disclosure.

[0028] [Figure 10] FIG. 1 is a schematic block diagram of an apparatus suitable for practicing embodiments of the present disclosure.

[0029] Throughout the drawings, the same or similar reference numbers represent the same or similar elements. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0030] The principles of the present disclosure will be described with reference to some embodiments. It should be understood that these embodiments are merely provided for illustrative purposes to aid those skilled in the art in understanding and implementing the present disclosure, and do not imply any limitations on the scope of the present disclosure. The present disclosure described herein can be implemented in various ways other than those described below.

[0031] In the following description and claims, unless defined otherwise, all technical and scientific terms used have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0032] As used herein, the term "terminal equipment" refers to any device having wireless or wired communication capabilities. Examples of terminal equipment include, but are not limited to, user equipment (UE), personal computers, desktop computers, mobile phones, mobile phones, smartphones, personal digital assistants (PDAs), portable computers, tablets, wearable devices, internet of things (IoT) devices, internet of everything (IoE) devices, machine type communication (MTC) devices, vehicle-mounted equipment for V2X communication (where X means pedestrian, vehicle or infrastructure / network), imaging devices such as digital cameras, gaming devices, music storage and playback devices, internet devices that enable wireless / wired internet access and browsing, etc. The term "terminal equipment" may be used interchangeably with UE, mobile station, subscriber equipment, mobile terminal, user terminal or wireless device. Additionally, the term "network equipment" refers to equipment capable of providing or hosting a cell or coverage through which terminal equipment can communicate. Examples of network devices include, but are not limited to, a Node B (NodeB or NB), an Evolved NodeB (eNodeB or eNB), a next generation NodeB (gNB), a transmit / receive point (TRP), a remote radio unit (RRU), a radio head (RH), a remote radio head (RRH), a femto node, a pico node, or other low power node.

[0033] In one embodiment, the terminal device may be connected to a first network device and a second network device. One of the first network device and the second network device may be a master node, and the other may be a secondary node. The first network device and the second network device may use different radio access technologies (RATs). In one embodiment, the first network device may be a first RAT device, and the second network device may be a second RAT device. In one embodiment, the first RAT device is an eNB, and the second RAT device is a gNB. Information related to the different RATs may be transmitted to the terminal device from at least one of the first network device or the second network device. In one embodiment, the first information may be transmitted from the first network device to the terminal device, and the second information may be transmitted from the second network device directly to the terminal device or via the first network device. In one embodiment, information related to the configuration of the terminal device set by the second network device may be transmitted from the second network device via the first network device. Information related to the reconfiguration of the terminal device set by the second network device may be transmitted from the second network device directly to the terminal device or via the first network device.

[0034] As used herein, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. The term "comprises" and variations thereof should be interpreted as open-ended terms meaning "including, but not limited to." The term "based on" should be interpreted as "based at least in part on." The terms "one embodiment" and "one embodiment" should be interpreted as "at least one embodiment." The term "another embodiment" should be interpreted as "at least one other embodiment." Terms such as "first," "second," and the like may refer to different objects or the same object. The following content may include other definitions, both explicit and implicit.

[0035] In some instances, values, processes or devices are referred to as "optimum," "lowest," "highest," "minimum," "maximum," etc. It is understood that such descriptions are intended to indicate choices among multiple functional alternatives that may be used, and that such choices are not necessarily better, smaller, higher, or more preferred than other choices.

[0036] As mentioned above, in NR Release 17, PUCCH carrier switching for HARQ feedback is proposed to reduce the delay of HARQ feedback for DL ​​heavy configurations in unpaired spectrum. This allows multiple UL carriers or cells with different TDD configurations for PUCCH transmission for HARQ feedback. However, it is necessary to consider how to implement PUCCH carrier switching, such as how to enable or disable PUCCH carrier switching, how to implement PUCCH carrier switching for SPS HARQ-ACK, how to handle interactions between PUCCH carrier switching for SPS HARQ-ACK and SPS HARQ-ACK deferral, or how to handle interactions between PUCCH carrier switching and intra-UE multiplexing or prioritization.

[0037] In view of this, an embodiment of the present disclosure provides a solution for solving the above problems or potential problems in PUCCH carrier switching. In this solution, for a cell group provided from a network device to a terminal device, a cell set is configured for PUCCH transmission for HARQ feedback of downlink transmission in a cell in the cell group. Upon receiving a downlink transmission from the network device in a cell in the cell group (also referred to as a first cell in this specification for convenience), the terminal device can determine a cell for PUCCH transmission for HARQ feedback for the downlink transmission from the cell set (also referred to as a second cell in this specification for convenience). In this way, PUCCH carrier switching can be flexibly performed between cell sets as needed, and the delay of HARQ feedback can be significantly reduced.

[0038] The embodiments of the present disclosure may be applied to any suitable scenario. For example, the embodiments of the present disclosure may be implemented in Ultra-reliable and Low Latency Communication (URLLC). Alternatively, the embodiments of the present disclosure may be implemented in any of the following: low-capability NR devices, new radio (NR) multiple-input and multiple-output (MIMO), NR sidelink enhancements, NR systems at frequencies above 52.6 GHz, NR operation extension to 71 GHz, narrow band-Internet of Things (NB-IoT) / enhanced Machine Type Communication (eMTC) in non-terrestrial networks (NTNs), NTNs, UE power saving enhancements, NR coverage extension, NB-IoT and LTE-MTC, integrated access and backhaul (IAB), NR multicast and broadcast services, or enhanced multi-radio dual connectivity.

[0039] The principles and implementations of the present disclosure are described in detail below with reference to the drawings.

[0040] Communication Network Example FIG. 1 illustrates a schematic diagram of an exemplary communication network 100 in which some embodiments of the present disclosure may be implemented. As shown in FIG. 1, the communication network 100 may include a terminal device 110 and a network device 120. In some embodiments, the network device 120 may provide services to the terminal device 110. It should be understood that the number of devices in FIG. 1 is shown for illustrative purposes and is not intended to imply any limitations on the present disclosure. The communication network 100 may include any suitable number of network devices and / or terminal devices suitable for implementing implementations of the present disclosure.

[0041] As shown in Figure 1, terminal device 110 may communicate with network device 120 via a channel, such as a wireless communication channel. Communications in communication network 100 may conform to any suitable standard, including, but not limited to, Global System for Mobile Communications (GSM), Long Term Evolution (LTE), LTE Evolution (LTE-Evolution), LTE Advanced (LTE-A), Wideband Code Division Multiple Access (WCDMA), Code Division Multiple Access (CDMA), GSM EDGE Radio Access Network (GERAN), Machine Type Communications (MTC), and the like. Furthermore, communications may be performed according to any generation of communication protocols now known or developed in the future. Examples of communication protocols include, but are not limited to, first generation (1G), second generation (2G), 2.5G, 2.75G, third generation (3G), fourth generation (4G), 4.5G, and fifth generation (5G) communication protocols.

[0042] In some embodiments, the terminal device 110 may transmit uplink data to the network device 120 via an uplink data channel transmission. For example, the uplink data channel transmission may be a Physical Uplink Shared Channel (PUSCH) transmission. Of course, any other suitable form is also possible.

[0043] In some embodiments, the terminal device 110 may transmit uplink control information (UCI), e.g., HARQ feedback information, to the network device 120 via an uplink control channel transmission. For example, the uplink control channel transmission may be a PUCCH transmission. Of course, any other suitable form is also possible.

[0044] In some embodiments, network device 120 may support multiple services with different priorities for terminal device 110, such as eMBB with lower priority and URLLC with higher priority. Thus, terminal device 110 may perform respective uplink data and / or uplink control channel transmissions for the different services. The uplink control channel transmissions may carry HARQ feedback for the different services, and the HARQ feedback may have different priorities corresponding to the different services.

[0045] In some embodiments, the network device 120 may provide multiple serving cells (not shown herein) to the terminal device 110, such as, for example, a primary cell (Pcell), a primary secondary cell (PScell), a secondary cell (Scell), a special cell (sPCell), etc. Each serving cell may correspond to a CC. The terminal device 110 may perform transmission to the network device 120 via a CC. Of course, the terminal device 110 may perform transmission to the network device 120 via multiple CCs, for example in case of CA.

[0046] In some scenarios, a cell group is provided from a network device 120 to a terminal device 110. According to the conventional solution, the UL carrier of PUCCH transmission for HARQ-ACK of PDSCH reception in all cells in the cell group is configured in only one cell in the cell group. The cell group is also referred to as a PUCCH group. FIG. 2A is a schematic diagram 200A showing an example scenario of HARQ feedback according to the conventional solution. In this example, the cell group provided from the network device to the terminal device includes CC#1 and CC#2. And CC#1 is configured as a Pcell for PUCCH transmission for HARQ feedback of the cell group.

[0047] As shown in FIG. 2A, DCI 201 may indicate that HARQ feedback for PDSCH 202 is transmitted by PUCCH 205 of CC#1, e.g., with HARQ-ACK timing value K1=2. DCI 203 may indicate that HARQ feedback for PDSCH 204 is also transmitted by PUCCH 205, e.g., with HARQ-ACK timing value K1=1. DCI 206 may indicate that HARQ feedback for PDSCH 207 is transmitted by PUCCH 208 of CC#1, e.g., with HARQ-ACK timing value K1=4. However, CC#2 has an available UL slot for PUCCH 209, which is earlier than PUCCH 208 of CC#1. According to the conventional solution, HARQ feedback for PDSCH 207 cannot be scheduled to be transmitted by PUCCH 209, since only CC#1 is configured for PUCCH transmission for the cell group. As a result, the low latency requirements of URLLC services may not be met.

[0048] According to an embodiment of the present disclosure, for at least one cell in a cell group, a UL carrier for PUCCH transmission is configured for HARQ-ACK of PDSCH reception in all cells in the cell group. In this case, PUCCH transmission for HARQ feedback can be performed in a cell with available early UL symbols in at least one cell. FIG. 2B is a schematic diagram 200B illustrating an example scenario of PUCCH carrier switching for HARQ feedback according to an embodiment of the present disclosure. In this example, a cell group provided from the network device 120 to the terminal device 110 may include CC#1 and CC#2. Then, CC#1 as a Pcell and CC#2 as an Scell ​​are both configured for HARQ feedback of the cell group. It should be understood that this is just an example and other suitable numbers of CCs are also possible.

[0049] As shown in FIG. 2B, DCI 211 may indicate that HARQ feedback for PDSCH 212 is transmitted by PUCCH 215, which is available early on CC#1, e.g., with HARQ-ACK timing value K1=2. DCI 213 may indicate that HARQ feedback for PDSCH 214 is also transmitted by PUCCH 215, which is available early on PDSCH 214, e.g., with HARQ-ACK timing value K1=1. DCI 216 may indicate that HARQ feedback for PDSCH 217 is transmitted by PUCCH 218, which is available early on CC#2, e.g., with HARQ-ACK timing value K1=1. In this way, the delay of HARQ feedback can be reduced. More details are provided below with reference to FIGs. 3A-7.

[0050] Example of Enabling or Disabling PUCCH Carrier Switching 3A is a flow chart illustrating a process 300A for communicating HARQ feedback in accordance with an embodiment of the present disclosure. For purposes of discussion, the process 300A is described with reference to FIG. 1. The process 300A may involve the terminal device 110 and the network device 120 shown in FIG.

[0051] As shown in FIG. 3A, the network device 120 may transmit (301) to the terminal device 110 a configuration for a cell set (for convenience also referred to herein as a PUCCH cell set) of uplink control transmissions (e.g., PUCCH transmissions) for HARQ feedback for downlink transmissions (e.g., PDSCH or PDCCH transmissions) in cells in the cell group. In some embodiments, the cell group includes a number of cells provided from the network device 120 to the terminal device 110. In some embodiments, the cell set is selected from a number of cells in the cell group. In some embodiments, a cell different from the cells of the cell group may be configured in the cell set.

[0052] In some embodiments, a cell set may include multiple PUCCH cells associated with the same cell group. That is, multiple cells for PUCCH transmission are configured in a PUCCH group. This will be described in detail with reference to FIG. 4. FIG. 4 is a schematic diagram 400 illustrating an example configuration of PUCCH carriers according to an embodiment of the present disclosure. As shown in FIG. 4, the network device 120 may configure a cell group 401 in the terminal device 110 for CA and configure a cell set 402 for PUCCH of HARQ feedback for the cell group 401. The cell group 401 includes CC#1 to CC#6, and the cell set 402 includes CC#1, CC#2, and CC#5. It should be noted that the number of cells in a cell group, the number of cell groups, and the number of PUCCH cells in a PUCCH cell set are merely for illustration and not for limitation.

[0053] In some embodiments, the cell group may include a first cell subgroup and a second cell subgroup. Also, the cell set may include a first PUCCH cell set (also referred to herein as a first cell subset) associated with the first cell subgroup and a second PUCCH cell set (also referred to herein as a second cell subset) associated with the second cell subgroup. Still referring to FIG. 4, a cell subgroup 411 including CC#1, CC#2, CC#3, and CC#4 and a cell subgroup 421 including CC#5 and CC#6 may be provided to the terminal device 110. In this embodiment, a PUCCH cell set 412 is configured for the cell subgroup 411, and a PUCCH cell set 422 is configured for the cell subgroup 421. The PUCCH cell set 412 includes CC#1 and CC#2, and the PUCCH cell set 422 includes CC#5. It should be noted that the number of cells in a cell subgroup, the number of cell subgroups, and the number of PUCCH cells in a PUCCH cell set are merely for illustration and are not intended to be limiting. In this embodiment, a cell subgroup is associated with a corresponding PUCCH cell set, and therefore is also referred to as a PUCCH group. For example, cell subgroup 411 may be a primary PUCCH group, and cell subgroup 421 may be a secondary PUCCH group.

[0054] In some scenarios, the network device 120 transmits (302) a downlink transmission (also referred to herein as a first downlink transmission for convenience) to the terminal device 110. In some embodiments, the downlink transmission may be an SPS downlink data transmission, such as an SPS PDSCH transmission. Of course, the downlink transmission may also be a dynamically scheduled downlink data transmission. In some embodiments, the downlink transmission may be a downlink control transmission, such as a PDCCH transmission for SPS release requesting HARQ feedback.

[0055] In some embodiments, the network device 120 may transmit (303) a configuration indicating whether a change in an uplink control transmission (also referred to herein for convenience as a first uplink control transmission) for a HARQ feedback for a downlink transmission (also referred to herein for convenience as a first HARQ feedback) from execution in a source cell in the cell set to execution in a target cell in the cell set is valid or not. In other words, the configuration indicates whether PUCCH carrier switching is enabled or disabled. In some embodiments, the configuration may indicate that PUCCH carrier switching is enabled. In some alternative embodiments, the configuration may indicate that PUCCH carrier switching is disabled. In this manner, the signaling for enabling PUCCH carrier switching can be designed to reduce delays.

[0056] In some embodiments, the network device 120 may transmit the configuration regarding the PUCCH carrier switching via a Radio Resource Control (RRC) message, such as a pucchCarrierSwitching or pucchCellSwitching parameter. Of course, any other suitable way to transmit this configuration is also possible.

[0057] In some embodiments, the configuration regarding PUCCH carrier switching may be specific to the terminal device 110. That is, PUCCH carrier switching may be configured or enabled per UE. For example, the pucchCarrierSwitching or pucchCellSwitching parameter may be a UE-specific RRC parameter. In this case, PUCCH carrier switching may be enabled for the entire cell group 401 for the terminal device 110, i.e., for both cell subgroups 411, 421 in FIG. 4.

[0058] In some embodiments, the configuration regarding PUCCH carrier switching may be associated with an identity (ID) of a PUCCH group, for example the ID of cell subgroup 411 or 421. That is, PUCCH carrier switching may be configured or enabled for each PUCCH group of the terminal device 110. For example, a pucchCarrierSwitching or pucchCellSwitching parameter may be associated with the ID of the PUCCH group. In some embodiments, the configuration may be associated by default with the primary PUCCH group (for example, cell subgroup 411). In some embodiments, the configuration may be associated by default with the secondary PUCCH group (for example, cell subgroup 421).

[0059] In some embodiments, the source cell may be in the first cell subset and the target cell may be in the second cell subset. In other words, PUCCH carrier switching may be configured or enabled across PUCCH groups. For example, as shown in FIG. 4, PUCCH transmission for HARQ feedback for PDSCH received on CC#1 may be switched between PUCCH cell set 412 and PUCCH cell set 422. In some embodiments, the network device 120 may indicate which PUCCH cell of which PUCCH group is used for PUCCH transmission, for example, by dynamic indication, predefined rule, or RRC indication.

[0060] In some embodiments, the configuration regarding PUCCH carrier switching may be associated with the priority of the first uplink control transmission. In other words, PUCCH carrier switching may be configured or enabled per priority or PUCCH configuration of the uplink control information (UCI) of the terminal device 110. For example, the pucchCarrierSwitching or pucchCellSwitching parameters may be priority-specific RRC parameters. In some embodiments, only PUCCH for high priority HARQ-ACK may be switched between multiple PUCCH cells. In this way, PUCCH carrier switching may be enabled more flexibly, for example based on service requirements.

[0061] In some alternative or additional embodiments, the configuration regarding PUCCH carrier switching may be associated with the scheduling of the first uplink control transmission. In other words, PUCCH carrier switching may be configured or enabled separately for UCI of a configured grant (CG) and for dynamically scheduled UCI. For example, the CG UCI may be SPS HARQ-ACK. Of course, any other suitable method may be implemented for the CG UCI. For example, the dynamically scheduled UCI may be HARQ-ACK for PDSCH of a dynamic grant (DG). Of course, any other suitable method may be implemented for the dynamically scheduled UCI.

[0062] Returning to FIG. 3A, upon receiving the downlink transmission, the terminal device 110 determines a cell of an uplink control transmission (also referred to herein as a second cell for convenience) for HARQ feedback for the downlink transmission (304). In some embodiments, the terminal device 110 may determine the second cell based on a configuration regarding PUCCH carrier switching. For example, if the configuration indicates that PUCCH carrier switching is enabled for the uplink control transmission, the terminal device 110 may perform PUCCH carrier switching, as necessary, within the corresponding PUCCH cell set to determine the second cell. If the configuration indicates that PUCCH carrier switching is disabled for the uplink control transmission, the terminal device 110 may determine the second cell without PUCCH carrier switching.

[0063] In some embodiments where PUCCH carrier switching is enabled, terminal device 110 may determine the second cell based on DCI received from network device 120. The DCI may include an indicator field indicating the second cell. In this manner, the PUCCH cell for PUCCH carrier switching can be dynamically indicated.

[0064] In some alternative embodiments where PUCCH carrier switching is enabled, the terminal device 110 may determine the second cell based on a predefined rule. In some embodiments, the terminal device 110 may determine the second cell from the PUCCH cell set based on the priority of the cell. For example, the terminal device 110 may determine whether a source cell with a first priority (e.g., the highest priority) in the PUCCH cell set is available for uplink control transmission in the slot or subslot. If the source cell is unavailable, the terminal device 110 may determine a second cell with a second priority from the PUCCH cell set that has enough valid symbols for the first uplink transmission in the slot or subslot. The second priority is lower than the first priority. It should be noted that the determination of the second cell may be performed in any other suitable manner and is not limited to the above example.

[0065] Once the second cell is determined, terminal device 110 may perform uplink control transmission on the second cell (305).

[0066] Example of Pucch carrier switching for HARQ-ACC in SPS As is well known, in SPS downlink transmission, the first SPS downlink transmission has an activation DCI, and subsequent SPS downlink transmissions have no corresponding DCI. As mentioned above, in some scenarios, the cell of PUCCH transmission for HARQ-ACK may be dynamically indicated by an indicator field of DCI, which means that the PUCCH carrier can be dynamically switched among multiple cells of PUCCH according to the indication of DCI. In this case, how to support PUCCH carrier switching of SPS downlink transmission should be considered. In view of this, the embodiment of the present disclosure provides a solution for supporting PUCCH carrier switching for SPS downlink transmission, which will be described in embodiments 1 and 2 in conjunction with FIG. 3B.

[0067] 3B is a flow chart illustrating another communication process 300B of HARQ feedback in accordance with an embodiment of the present disclosure. For purposes of discussion, the process 300B is described with reference to FIG. 1. The process 300B may relate to the terminal device 110 and the network device 120 shown in FIG. 1. Assume that a downlink transmission from the network device 120 (also referred to herein as a first downlink transmission) is received by the terminal device 110 in a first cell.

[0068] EMBODIMENT 1 As shown in FIG. 3B, the network device 120 may determine (311) whether the downlink transmission is dynamically scheduled, semi-persistently scheduled, a retransmission of an SPS downlink data transmission, or for release of an SPS configuration.

[0069] In some embodiments, if the downlink transmission is dynamically scheduled, the terminal device 110 may determine a second cell for an uplink control transmission for HARQ feedback for the downlink transmission based on the DCI indication received from the network device 120 for the downlink transmission, and perform the uplink control transmission in the second cell (312).

[0070] In some embodiments, if the downlink transmission is semi-persistently scheduled, the terminal device 110 may cancel 313 the uplink control transmission for HARQ feedback for the downlink transmission. That is, PUCCH carrier switching for HARQ feedback for SPS downlink transmission is always not supported, regardless of the first SPS downlink transmission with an activation DCI or a subsequent SPS downlink transmission without DCI. For example, if the PUCCH resource in the Pcell for HARQ-ACK for SPS PDSCH collides with DL symbols / SSB symbols / CORESET 0, the terminal device 110 may drop the HARQ-ACK.

[0071] In some embodiments, if the downlink transmission is a retransmission of an SPS downlink data transmission or for release of an SPS configuration, the terminal device 110 may determine a second cell based on an indication in the DCI (314) and perform an uplink control transmission for retransmission or release in the second cell (315). That is, PUCCH carrier switching is supported for SPS downlink data transmission or HARQ feedback for release of an SPS configuration. For example, if the PUCCH resource in a Pcell for HARQ-ACK for SPS PDSCH Re-Tx or SPS release collides with DL symbol / SSB / CORESET 0, the terminal device 110 may transmit a PUCCH for HARQ-ACK in the cell indicated by the corresponding PDCCH.

[0072] In this way, in order to increase the spectrum efficiency and reduce the delay when the PUCCH configured for SPS HARQ-ACK is unavailable, a PUCCH carrier switching mechanism for SPS HARQ-ACK can be designed in a simple manner.

[0073] EMBODIMENT 2 This embodiment is an alternative to embodiment 1. Continuing to refer to FIG. 3B, the terminal device 110 may determine (316) whether the downlink transmission is the first of an SPS downlink data transmission, a retransmission of an SPS downlink data transmission, or for the release of an SPS configuration.

[0074] In some embodiments, if the downlink transmission is for an initial one of the SPS downlink data transmissions, a retransmission of an SPS downlink data transmission, or a release of an SPS configuration, the terminal device 110 may determine a second cell based on the indication in the DCI and perform an uplink control transmission for the initial one of the SPS downlink data transmissions, the retransmission, or the release in the second cell (317).

[0075] That is, carrier switching of PUCCH is supported for the first SPS downlink data transmission with activation DCI, the retransmission of SPS downlink data transmission scheduled by DCI, and HARQ feedback for downlink control transmission for release of SPS configuration. For example, if the PUCCH resource in a Pcell for the first SPS PDSCH with activation DCI, or the retransmission of SPS PDSCH, or the HARQ-ACK for SPS release collides with DL symbol / SSB / CORESET 0, the terminal device 110 may transmit the PUCCH for HARQ-ACK in the cell indicated by the corresponding PDCCH.

[0076] In some embodiments, if the downlink transmission is an SPS downlink data transmission without DCI, terminal device 110 may cancel the uplink control transmission for the SPS downlink data transmission without DCI 318. For example, if the PUCCH resource corresponding to only the SPS PDSCH in the Pcell collides with DL symbols / SSB / CORESET 0, terminal device 110 may drop the HARQ-ACK.

[0077] For clarity, some examples will be described in conjunction with Fig. 5. Fig. 5A is a schematic diagram 500A illustrating an example of PUCCH carrier switching for SPS HARQ-ACK according to an embodiment of the present disclosure. Assume that a cell group includes CC#1 as a Pcell and CC#2 as an Scell, and the PUCCH cell set for the cell group includes CC#1 and CC#2.

[0078] As shown in FIG. 5A, DCI 501 may indicate that HARQ feedback for PDSCH 502 is transmitted by PUCCH 503 of CC#1, for example, with HARQ-ACK timing value K1=2. SPS PDSCH 504 and SPS PDSCH 505 are not accompanied by DCI. HARQ feedback for SPS PDSCH 504 is configured to be transmitted by PUCCH 503, for example, with HARQ-ACK timing value K1=2. HARQ feedback for SPS PDSCH 505 is configured to be transmitted by PUCCH 506, for example, with HARQ-ACK timing value K1=2. However, PUCCH 506 is unavailable because it is in a DL slot. In this case, the terminal device 110 may drop the HARQ feedback for SPS PDSCH 505.

[0079] In some embodiments where the downlink transmission is an SPS downlink data transmission without DCI, if an uplink control transmission (i.e., a first uplink control transmission) for HARQ feedback for a downlink transmission (i.e., a first HARQ feedback) and a second uplink control transmission for a second HARQ feedback for a dynamically scheduled downlink data transmission are transmitted in the same slot, the terminal device 110 may multiplex the first HARQ feedback into the second uplink control transmission (319) and cancel the first uplink control transmission (320). The terminal device 110 may then perform the second uplink control transmission with the first HARQ feedback multiplexed therein (321). For example, if the HARQ-ACK for the SPS PDSCH and the HARQ-ACK for the DG PDSCH are in the same slot or subslot, the terminal device 110 may first multiplex the HARQ-ACK for the SPS PDSCH and the DG PDSCH with the same codebook as Release 16, and transmit the HARQ-ACK codebook on the PUCCH of the cell indicated by the scheduling DCI of the DG PDSCH.

[0080] For clarity, some examples will be described in conjunction with FIG. 5B, which is a schematic diagram 500B illustrating another example of PUCCH carrier switching for SPS HARQ-ACK according to an embodiment of the present disclosure. Assume that a cell group includes CC#1 as a Pcell and CC#2 as an Scell, and the PUCCH cell set for the cell group includes CC#1 and CC#2.

[0081] As shown in FIG. 5B, DCI 511 may indicate that HARQ feedback for PDSCH 512 is transmitted by PUCCH 513 of CC#1, for example, with HARQ-ACK timing value K1=2. SPS PDSCH 514 and SPS PDSCH 515 are not accompanied by DCI. HARQ feedback for SPS PDSCH 514 is configured to be transmitted by PUCCH 513, for example, with HARQ-ACK timing value K1=2. HARQ feedback for SPS PDSCH 515 is configured to be transmitted by PUCCH 516, for example, with HARQ-ACK timing value K1=2. PUCCH 516 is unavailable because it is in a DL slot. However, DCI 517 indicates that HARQ feedback for PDSCH 518 in CC#1 is transmitted by PUCCH 519 of CC#2, for example, with HARQ-ACK timing value K1=1. PUCCH 516 and PUCCH 519 are in the same slot. In this case, terminal device 110 may multiplex HARQ feedback for SPS PDSCH 515 into PUCCH 519 and cancel PUCCH 516.

[0082] Compared with embodiment 1, the PUCCH carrier switching in this embodiment is more complicated but more efficient.

[0083] Example of interaction between PUCCH carrier switching of SPS HARQ-ACK and postponement of SPS HARQ-ACK As mentioned above, in some scenarios, the PUCCH cell for PUCCH carrier switching may be determined based on a predefined rule. In some other scenarios, if the PUCCH resource in the Pcell for SPS HARQ-ACK is not available, SPS HARQ-ACK postponement may be configured to delay the SPS HARQ-ACK until the next available PUCCH resource that does not overlap with DL symbols. For this reason, when SPS HARQ-ACK postponement and PUCCH carrier switching for HARQ-ACK are configured simultaneously for the terminal device 110, the UE behavior of whether to perform PUCCH carrier switching first or SPS HARQ-ACK postponement first should be defined. Otherwise, the terminal device 110 and the network device 120 may have different understandings of SPS HARQ-ACK transmission, which may result in degraded system performance. For clarity, this will be described in conjunction with FIG. 6.

[0084] 6 is a schematic diagram 600 illustrating an example of an interaction between PUCCH carrier switching for SPS HARQ-ACK and SPS HARQ-ACK postponement according to an embodiment of the present disclosure. Assume that a cell group includes CC#1 as a Pcell and CC#2 as an Scell, and a PUCCH cell set for the cell group includes CC#1 and CC#2. Assume also that SPS HARQ-ACK postponement and PUCCH carrier switching for HARQ-ACK are configured for the terminal device 110 at the same time.

[0085] As shown in FIG. 6, the HARQ feedback for the SPS PDSCH 601 of the SPS configuration #1 is configured to be transmitted by the PUCCH 602, for example, with a HARQ-ACK timing value K1=2. The HARQ feedback for the SPS PDSCH 603 of the SPS configuration #1 is configured to be transmitted by the PUCCH 604, for example, with a HARQ-ACK timing value K1=2. The PUCCH 604 is in a DL slot and is therefore unavailable. According to the SPS HARQ-ACK postponement, the HARQ feedback for the SPS PDSCH 603 will be delayed to be transmitted by the PUCCH 606. However, according to the PUCCH carrier switching, the HARQ feedback for the SPS PDSCH 603 will be transmitted by the PUCCH 605 of CC#2 in the same slot as the PUCCH 604. Therefore, the UE's operation in this case must be defined so that the network device 120 can correctly receive the HARQ-ACK from the terminal device 110. In view of this, embodiments of the present disclosure provide a solution to this scenario, which will be described in embodiments 3 and 4 in conjunction with FIG. 3C.

[0086] 3C is a flow chart illustrating another process 300C for communicating HARQ feedback in accordance with an embodiment of the present disclosure. For purposes of discussion, the process 300C is described with reference to FIG. 1. The process 300C may involve terminal device 110 and network device 120 shown in FIG. 1. Assume that a downlink transmission from network device 120 (also referred to herein as a first downlink transmission) is received by terminal device 110 in a first cell.

[0087] EMBODIMENT 3 In this embodiment, PUCCH carrier switching for HARQ-ACK takes priority over SPS HARQ-ACK postponement. For example, if the PUCCH resource in Pcell for SPS HARQ-ACK is unavailable, the terminal device 110 may first determine another PUCCH cell for SPS HARQ-ACK transmission based on a predetermined rule of PUCCH carrier switching. If an available PUCCH resource is found, the terminal device 110 transmits SPS HARQ-ACK in the PUCCH resource; otherwise, the terminal device 110 postpones SPS HARQ-ACK to the next available PUCCH resource.

[0088] 3C, the terminal device 110 may determine whether the downlink transmission is an SPS downlink data transmission (331). If the downlink transmission is an SPS downlink data transmission, the terminal device 110 may determine whether an uplink control transmission in a slot or subslot at a source cell having a first priority is available (332). The uplink control transmission is for HARQ feedback for the SPS downlink data transmission.

[0089] If uplink control transmission in the source cell is unavailable, the terminal device 110 may determine whether a second-priority target cell with enough valid symbols for uplink transmission in the slot or subslot exists in the PUCCH cell set (333). The first priority is higher than the second priority. If the target cell exists in the PUCCH cell set, the terminal device 110 may determine the target cell as the second cell and perform uplink control transmission for HARQ feedback for SPS downlink data transmission in the second cell (334).

[0090] If the target cell is not in the PUCCH cell set, the terminal device 110 may delay the uplink control transmission in the source cell (335). For example, referring to FIG. 6, if PUCCH 605 is available for uplink control transmission, the HARQ-ACK for SPS PDSCH 603 will be switched to be transmitted by PUCCH 605 of CC#2. If PUCCH 605 is not available for uplink control transmission, the HARQ-ACK for SPS PDSCH 603 will be delayed to be transmitted by PUCCH 606. Note that this is merely an example and is not intended to limit the present disclosure.

[0091] Although it may be necessary to configure PUCCH resources in multiple cells for the SPS PDSCH, low latency can be achieved in this way.

[0092] EMBODIMENT 4 This embodiment is an alternative to embodiment 3. In this embodiment, SPS HARQ-ACK postponement takes priority over PUCCH carrier switching for HARQ-ACK. For example, when SPS HARQ-ACK postponement is configured, PUCCH carrier switching for SPS HARQ-ACK is disabled. If PUCCH resources in Pcell for SPS HARQ-ACK are not available, the terminal device 110 will delay SPS HARQ-ACK to the next available PUCCH resource.

[0093] Continuing to refer to FIG. 3C, the terminal device 110 may determine whether an uplink control transmission in a slot or subslot in a source cell having a first priority is available (336). If an uplink control transmission in the source cell is not available, the terminal device 110 may determine a second cell of a second priority from the PUCCH cell set that has enough valid symbols for an uplink control transmission in the slot or subslot. The first priority is higher than the second priority. The terminal device 110 may then perform an uplink control transmission in the second cell (337).

[0094] In some embodiments, terminal device 110 may receive 338 from network device 120 a configuration indicating that SPS HARQ-ACK deferral is enabled, i.e., the configuration indicates that it is enabled to delay HARQ feedback for SPS downlink data transmissions in uplink control transmissions in a cell when uplink control transmissions are unavailable in the cell.

[0095] Upon receiving a configuration indicating that SPS HARQ-ACK deferral is enabled, if the downlink transmission is an SPS downlink data transmission and an uplink control transmission in the source cell is unavailable, the terminal device 110 may delay 339 an uplink control transmission in the source cell. For example, referring to FIG. 6, if PUCCH 604 is unavailable, the HARQ-ACK for SPS PDSCH 603 will be directly delayed to be transmitted by PUCCH 606.

[0096] This reduces the impact on the 3GPP specifications and avoids the need to configure PUCCH resources for SPS PDSCH in multiple cells.

[0097] Example of Interaction Between PUCCH Carrier Switching and Intra-UE Multiplexing In some scenarios, a first PUCCH transmission may overlap with a second PUCCH or PUSCH transmission in the time domain, in which case the overlap may be resolved by multiplexing or prioritizing the first PUCCH transmission with the second PUCCH or PUSCH transmission, which is also referred to herein as intra-UE multiplexing.

[0098] As mentioned above, in some scenarios, the PUCCH cell for PUCCH carrier switching may be determined based on a predefined rule. In this case, there may be an overlap in the time domain between the switched PUCCH or the original unavailable PUCCH and other PUSCHs or PUCCHs. Taking this overlap into account, it is necessary to determine the interaction between intra-UE multiplexing and PUCCH carrier switching so that the terminal device 110 and the network device 120 have the same understanding of HARQ-ACK transmission. For clarity, this will be described in conjunction with FIG. 7A.

[0099] 7A is a schematic diagram 700A illustrating an example of the interaction between PUCCH carrier switching and intra-UE multiplexing or prioritization according to an embodiment of the present disclosure. Assume that a cell group includes CC#1 as a 30KHz Pcell, CC#2 as a 60KHz Scell, and CC#3 as a 60KHz Scell, and the PUCCH cell set for the cell group includes CC#1 and CC#2.

[0100] As shown in Fig. 7A, DCI 701 may indicate that HARQ feedback for PDSCH 702 is transmitted by PUCCH 703 of CC#1, for example with HARQ-ACK timing value K2=1. DCI 704 may indicate that HARQ feedback for PDSCH 705 is transmitted by PUCCH 706 of CC#1, for example with HARQ-ACK timing value K2=1. However, PUCCH 706 is unavailable since it is in DL slot of CC#1. According to the PUCCH carrier switching based on the predetermined rule, HARQ-ACK for PDSCH 705 can be switched to be transmitted by PUCCH 709 of the same slot of CC#2.

[0101] However, DCI 707 may be scheduled onto PUSCH 708 of CC#3 with scheduling offset K2 = 1. According to intra-UE multiplexing, HARQ-ACK for PDSCH 705 may be multiplexed onto PUSCH 708 and PUCCH 706 is cancelled.

[0102] As can be seen, intra-UE multiplexing and PUCCH carrier switching may cause different HARQ-ACK transmissions for the PDSCH 705. Therefore, it is necessary to determine the interplay between intra-UE multiplexing and PUCCH carrier switching so that the terminal device 110 and the network device 120 have the same understanding of the HARQ-ACK transmission. In view of this, an embodiment of the present disclosure provides a solution to this scenario, which will be described in embodiments 5 and 6 in conjunction with FIG. 3D.

[0103] 3D is a flow chart illustrating another process 300D for communicating HARQ feedback in accordance with an embodiment of the present disclosure. For purposes of discussion, the process 300D is described with reference to FIG. 1. The process 300D may involve terminal device 110 and network device 120 shown in FIG. 1. Assume that a downlink transmission from network device 120 (also referred to herein as a first downlink transmission) is received by terminal device 110 in a first cell.

[0104] EMBODIMENT 5 In this embodiment, intra-UE multiplexing takes priority over PUCCH carrier switching, where multiple cells are configured for PUCCH transmission within a PUCCH group.

[0105] 3D, the terminal device 110 may determine a source cell from a PUCCH cell set of an uplink control transmission for HARQ feedback for a downlink transmission based on a predetermined rule (341). For example, the terminal device 110 may first determine a PUCCH resource in a Pcell for HARQ-ACK transmission in a slot indicated by a k1 value as the source cell.

[0106] The terminal device 110 may determine whether an uplink control transmission in the source cell overlaps with an uplink transmission (e.g., a PUCCH or a PUSCH) in the time domain (342). If the uplink control transmission overlaps with an uplink transmission, the terminal device 110 may generate a final uplink transmission by multiplexing or prioritizing the uplink control transmission and the uplink transmission (343). For example, the terminal device 110 may perform intra-UE multiplexing of any other PUCCH / PUSCH that overlaps with the PUCCH to obtain a final PUCCH / PUSCH.

[0107] If the final uplink transmission is unavailable, the terminal device 110 may determine whether an uplink control transmission in the source cell is available (344). If the uplink control transmission in the source cell is available, the terminal device 110 may perform an uplink control transmission in the source cell (345). If the uplink control transmission in the source cell is unavailable, the terminal device 110 may determine a second cell of a second priority that has enough valid symbols for the uplink control transmission in the slot or subslot (346). The first priority is higher than the second priority. For example, if the final PUCCH / PUSCH collides with DL symbols / SSB symbols / CORESET#0, the terminal device 110 may determine an available PUCCH with enough UL OFDM symbols for HARQ-ACK transmission in the PUCCH cell based on a predefined cell selection order.

[0108] Then, the terminal device 110 may perform uplink control transmission in the second cell (347). That is, PUCCH carrier switching is selectively performed after intra-UE multiplexing. Referring to FIG. 7A, the HARQ-ACK for the PDSCH 705 is multiplexed into the PUSCH 708 and transmitted to the network device 120 by the PUSCH 708.

[0109] In some embodiments, if the uplink control transmission in the second cell overlaps with another uplink transmission, the terminal device 110 may consider that an error has occurred. In other words, the terminal device 110 does not assume that the switched PUCCH determined for HARQ-ACK overlaps with another PUCCH and / or PUSCH. For clarity, this is described in conjunction with FIG. 7B, which is a schematic diagram 700B illustrating an example scenario of interaction between PUCCH carrier switching and intra-UE multiplexing according to an embodiment of the present disclosure.

[0110] Referring to FIG. 7B, DCI 711 may indicate that HARQ feedback for PDSCH 712 is transmitted by PUCCH 713 of CC#1, for example with HARQ-ACK timing value K1=2. However, PUCCH 713 is in DL slot of CC#1 and is therefore unavailable. According to PUCCH carrier switching based on a predetermined rule, HARQ-ACK for PDSCH 712 can be switched to be transmitted by PUCCH 714 in the same slot of CC#2. However, PUCCH 714 will overlap with PUSCH 715 of CC#1 in the same slot. The terminal device 110 does not expect this situation to occur and considers this situation an error.

[0111] EMBODIMENT 6 This embodiment is an alternative to embodiment 5. In this embodiment, PUCCH carrier switching is prioritized over intra-UE multiplexing, and again multiple cells are configured for PUCCH transmission within a PUCCH group.

[0112] 3D , upon receiving the downlink transmission at the first cell, the terminal device 110 may determine a source cell from the PUCCH cell set of the uplink control transmission for HARQ feedback for the downlink transmission based on a predetermined rule (348). For example, the terminal device 110 may first determine a PUCCH resource in a Pcell for HARQ-ACK transmission in a slot indicated by the k1 value as the source cell.

[0113] Then, the terminal device 110 may determine whether an uplink control transmission in a source cell having a first priority is available (349). If an uplink control transmission in a source cell is not available, the terminal device 110 may determine a second cell of a second priority from the PUCCH cell set that has enough valid symbols for uplink control transmission in a slot or subslot (350). The first priority is higher than the second priority. For example, the terminal device 110 may determine whether the PUCCH collides with DL symbols / SSB symbols / CORESET#0, and if the PUCCH collides with DL symbols / SSB symbols / CORESET#0, the terminal device 110 may determine an available PUCCH (i.e., a switched PUCCH) that has enough UL OFDM symbols for HARQ-ACK transmission in the cell based on a predefined cell selection order.

[0114] The terminal device 110 may determine whether an uplink control transmission in the second cell overlaps with an uplink transmission (e.g., a PUCCH or a PUSCH) in the time domain (351). If the uplink control transmission overlaps with an uplink data transmission, the terminal device 110 may multiplex HARQ feedback for the downlink transmission into the uplink data transmission (352) and cancel the uplink control transmission (353). The terminal device 110 may perform an uplink data transmission with the multiplexed HARQ feedback (354).

[0115] If the uplink control transmission in the second cell overlaps in the time domain with another uplink control transmission (also referred to herein as a third uplink control transmission for convenience) having uplink control information, the terminal device 110 may determine (355) that an error has occurred, i.e., the terminal device 110 does not anticipate such a case occurring.

[0116] In some alternative embodiments, if the uplink control transmission in the second cell overlaps in the time domain with a third uplink control transmission having uplink control information, the terminal device 110 may perform (356) the uplink control transmission while canceling the third uplink control transmission, i.e., the terminal device 110 may transmit only the switched PUCCH and drop the UCI on the other PUCCH.

[0117] In some alternative embodiments, if the uplink control transmission in the second cell overlaps in the time domain with the third uplink control transmission having uplink control information, the terminal device 110 may perform the uplink control transmission and the third uplink control transmission simultaneously (357), i.e., the terminal device 110 transmits two PUCCHs at the same time.

[0118] In some alternative embodiments, if an uplink control transmission in the second cell overlaps in the time domain with a third uplink control transmission having uplink control information, the terminal device 110 may multiplex (358) the uplink control information into the first uplink control transmission while canceling the third uplink control transmission, i.e., the terminal device 110 may multiplex all UCI into the switched PUCCH and cancel the other PUCCH.

[0119] In this way, clear rules are defined for the order of intra-UE multiplexing and PUCCH carrier switching for HARQ-ACK, ensuring consistency between the network device 120 and the terminal device 110 in HARQ-ACK transmission.

[0120] Exemplary implementation of the method In response to the above, embodiments of the present disclosure provide communication methods implemented in a terminal device and a network device, which are described below with reference to FIGS.

[0121] 8 illustrates an exemplary communication method 800 implemented in a terminal device according to some embodiments of the present disclosure. For example, the method 800 may be performed in a terminal device 110 as shown in FIG. 1. For purposes of discussion, the method 800 is described below with reference to FIG. 1. It should be understood that the method 800 may include additional blocks not shown and / or omit some blocks shown, and that the scope of the present disclosure is not limited in this respect.

[0122] At block 810, the terminal device 110 receives a first downlink transmission in a first cell in the cell group from the network device 120. In some embodiments, the first downlink transmission may be a downlink data transmission. In some embodiments, the first downlink transmission may be a downlink control transmission.

[0123] In block 820, the terminal device 110 determines a second cell for the first uplink control transmission for the first HARQ feedback for the first downlink transmission from a cell set for the uplink control transmission associated with the cell group. In some embodiments, the terminal device 110 may receive a configuration from the network device 120 indicating that a change is in effect for the first uplink control transmission from performing in a source cell in the cell set to performing in a target cell in the cell set, and determine the second cell based on the configuration.

[0124] In some embodiments, the configuration is specific to the terminal device 110. In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup. The cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup. The first cell is in the first cell subgroup and the configuration is associated with an identity of the first cell subgroup.

[0125] In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup, the cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup, the first cell is in the first cell subgroup, the source cell is in the first cell subset, and the target cell is in the second cell subset.

[0126] In some embodiments, the configuration is associated with at least one of a priority or a scheduling of the first uplink control transmission. In this manner, PUCCH carrier switching can be enabled or disabled.

[0127] In some embodiments, if the first downlink transmission is dynamically scheduled, the terminal device 110 may determine the second cell based on an indication in the downlink control information received from the network device for the first downlink transmission. In some embodiments, if the first downlink transmission is semi-persistently scheduled, the terminal device 110 may cancel the first uplink control transmission. In some embodiments, if the first downlink transmission is a retransmission of a semi-persistently scheduled downlink data transmission or for release of a semi-persistent scheduling configuration, the terminal device 110 may determine the second cell based on an indication in the downlink control information. In this way, PUCCH carrier switching for SPS HARQ-ACK can be realized in a simple manner.

[0128] In some embodiments, if the first downlink transmission is for at least one of an initial one of semi-persistently scheduled downlink data transmissions, a retransmission of a semi-persistently scheduled downlink data transmission, or a release of a semi-persistent scheduling configuration, terminal device 110 may determine the second cell based on an indication in the downlink control information. In some embodiments, if the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information, terminal device 110 may cancel the first uplink control transmission.

[0129] In some embodiments, when the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information, and the first uplink control transmission and the second uplink control transmission for the second HARQ feedback for the dynamically scheduled downlink data transmission are transmitted in the same slot, the terminal device 110 may multiplex the first HARQ feedback into the second uplink control transmission and cancel the first uplink control transmission. In this way, PUCCH carrier switching for SPS HARQ-ACK can be realized in an effective manner.

[0130] In some embodiments, the terminal device 110 may receive a configuration from the network device 120 indicating that it is valid to delay HARQ feedback for semi-persistently scheduled downlink data transmissions in an uplink control transmission in a cell when an uplink control transmission is unavailable in the cell. In these embodiments, if the first downlink transmission is a semi-persistently scheduled downlink data transmission, the terminal device 110 may determine whether a first uplink control transmission in a slot or sub-slot in a source cell having a first priority is available. If the first uplink control transmission in the source cell is unavailable, the terminal device 110 may determine whether a target cell of a second priority exists in the cell set that has enough valid symbols for the first uplink transmission in the slot or sub-slot. The first priority is higher than the second priority. If the target cell exists in the cell set, the terminal device 110 may determine the target cell as the second cell. If the target cell does not exist in the cell set, the terminal device 110 may delay the first uplink control transmission in the source cell. In this way, an interaction between PUCCH carrier switching for SPS HARQ-ACK and SPS HARQ-ACK deferral can be defined, i.e., PUCCH carrier switching for SPS HARQ-ACK takes priority over SPS HARQ-ACK deferral.

[0131] In some alternative embodiments, the terminal device 110 may determine whether a first uplink control transmission in a slot or sub-slot in a source cell having a first priority is available. If the first uplink control transmission in the source cell is unavailable, the terminal device 110 may determine a second cell of a second priority from the cell set that has enough valid symbols for the first uplink control transmission in the slot or sub-slot. The first priority is higher than the second priority. If the first downlink transmission is a semi-persistently scheduled downlink data transmission and the first uplink control transmission in the source cell is unavailable, the terminal device 110 may delay the first uplink control transmission in the source cell. In this manner, an interaction between PUCCH carrier switching for SPS HARQ-ACK and SPS HARQ-ACK deferral can also be defined. That is, SPS HARQ-ACK deferral takes precedence over PUCCH carrier switching for SPS HARQ-ACK.

[0132] In some embodiments, if the first uplink control transmission at the source cell overlaps with the uplink transmission in the time domain, the terminal device 110 may generate a final uplink transmission by multiplexing or prioritizing the first uplink control transmission and the uplink transmission. If the final uplink transmission is not available, the terminal device 110 may determine whether the first uplink control transmission at the source cell is available. If the first uplink control transmission at the source cell is not available, the terminal device 110 may determine a second cell of a second priority from the cell set that provides enough valid symbols for the first uplink control transmission in the slot or subslot. The first priority is higher than the second priority. The first uplink control transmission can then be performed in the second cell. In this manner, an interaction between PUCCH carrier switching for HARQ-ACK and intra-UE multiplexing can also be defined. That is, intra-UE multiplexing is prioritized over PUCCH carrier switching for HARQ-ACK.

[0133] In some alternative embodiments, if the first uplink control transmission in the second cell overlaps in the time domain with the uplink data transmission, the terminal device 110 may multiplex the first HARQ feedback into the uplink data transmission and cancel the first uplink control transmission. In some embodiments, if the first uplink control transmission in the second cell overlaps in the time domain with a third uplink control transmission having uplink control information, the terminal device 110 may perform one of the following: determine that an error has occurred, perform the first uplink control transmission while canceling the third uplink control transmission, perform the first uplink control transmission and the third uplink control transmission simultaneously, or multiplex the uplink control information into the first uplink control transmission while canceling the third uplink control transmission.

[0134] In this method, too, an interaction between PUCCH carrier switching for HARQ-ACK and intra-UE multiplexing can be defined, i.e., PUCCH carrier switching for HARQ-ACK takes priority over intra-UE multiplexing.

[0135] 9 illustrates an exemplary communication method 900 implemented in a network device according to some embodiments of the present disclosure. For example, the method 900 may be performed in the network device 120 as shown in FIG. 1. For purposes of discussion, the method 900 is described below with reference to FIG. 1. It should be understood that the method 900 may include additional blocks not shown and / or omit some of the blocks shown, and that the scope of the present disclosure is not limited in this respect.

[0136] 9, in block 910, the network device 120 transmits a first downlink transmission in a first cell in the cell group to the terminal device 110. In some embodiments, the network device 120 may transmit a configuration to the terminal device 110 indicating that a change is in effect for the first uplink control transmission from performing in a source cell in the set of cells to performing in a target cell in the set of cells.

[0137] In some embodiments, the configuration is specific to the terminal device 110. In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup. The cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup. The first cell is in the first cell subgroup and the configuration is associated with an identity of the first cell subgroup.

[0138] In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup, the cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup, the first cell is in the first cell subgroup, the source cell is in the first cell subset, and the target cell is in the second cell subset.

[0139] In some embodiments, the configuration is associated with at least one of a priority or a scheduling of the first uplink control transmission. In this manner, PUCCH carrier switching can be enabled or disabled.

[0140] In block 920, the network device 120 receives, from the terminal device 110, a first HARQ feedback for the first downlink transmission in a second cell. The second cell is determined from a cell set for uplink control transmission associated with the cell group. In some embodiments where the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information, the network device 120 may receive, from the terminal device 110, a second uplink control transmission multiplexed with the first HARQ feedback and obtain the first HARQ feedback from the second uplink control transmission. The second uplink control transmission is for the second HARQ feedback for the dynamically scheduled downlink data transmission.

[0141] In some embodiments, the network device 120 may transmit a configuration to the terminal device 110 indicating that delaying HARQ feedback for semi-persistently scheduled downlink data transmissions in an uplink control transmission in the cell is enabled when an uplink control transmission is unavailable in the cell. In some embodiments, the network device 120 may receive the first HARQ feedback by at least one of simultaneously receiving from the terminal device 110 the first uplink control transmission and a third uplink control transmission having uplink control information, or receiving from the terminal device 110 the first uplink control transmission multiplexed with the uplink control information.

[0142] Exemplary implementation of the device Fig. 10 is a schematic block diagram of an apparatus 1000 suitable for implementing embodiments of the present disclosure. The apparatus 1000 can be considered as a further exemplary implementation of the terminal device 110 or the network device 120 shown in Fig. 1. Thus, the apparatus 1000 can be implemented in or at least as part of the terminal device 110 or the network device 120.

[0143] As shown in the figure, the apparatus 1000 includes a processor 1010, a memory 1020 coupled to the processor 1010, a suitable transmitter (TX) and receiver (RX) 1040 coupled to the processor 1010, and a communication interface coupled to the TX / RX 1040. The memory 1010 stores at least a portion of a program 1030. The TX / RX 1040 is for bidirectional communication. The TX / RX 1040 has at least one antenna to facilitate communication, although in practice the access nodes described herein may have multiple antennas. The communication interface may represent any interface required for communication with other network elements, for example, an X2 / Xn interface for bidirectional communication between eNBs / gNBs, an S1 / NG interface for communication between a Mobility Management Entity (MME) / Access and Mobility Management Function (AMF) / SGW / UPF and an eNB / gNB, an Un interface for communication between an eNB / gNB and a Relay Node (RN), or a Uu interface for communication between an eNB / gNB and a terminal device.

[0144] The program 1030 may be considered to include program instructions that, when executed by an associated processor 1010, enable the device 1000 to operate in accordance with embodiments of the present disclosure, as discussed herein with reference to Figures 3A-9. The embodiments of the present disclosure may be implemented by computer software, hardware, or a combination of software and hardware executable by the processor 1010 of the device 1000. The processor 1010 may be configured to implement various embodiments of the present disclosure. The combination of the processor 1010 and the memory 1020 may also constitute a processing means 1050 suitable for implementing embodiments of the present disclosure.

[0145] The memory 1020 may be of any type suitable for the local technology network and may be implemented by any suitable data storage technology, including, but not limited to, computer-readable non-transitory storage media, semiconductor-based storage devices, magnetic storage devices and systems, optical storage devices and systems, fixed and removable memories, etc. Although only one memory 1020 is shown in the device 1000, multiple physically distinct memory modules may be installed in the device 1000. The processor 1010 may be of any type suitable for the local technology network and may include, but is not limited to, one or more of the following: general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), and processors based on multi-core processor configurations. The device 1000 may have multiple processors, for example application specific integrated circuit chips time-slaved to a clock synchronous with a master processor.

[0146] In some embodiments, the terminal device includes circuitry configured to receive, from the network device, a first downlink transmission at a first cell of a cell group, and determine, from a cell set for uplink control transmissions associated with the cell group, a second cell of the first uplink control transmission for first HARQ feedback for the first downlink transmission.

[0147] In some embodiments, the circuitry may be configured to determine the second cell by receiving a configuration from the network device indicating that a change is in effect for the first uplink control transmission from performing in a source cell in the cell set to performing in a target cell in the cell set, and determining the second cell based on the configuration.

[0148] In some embodiments, the configuration is terminal device specific. In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup. The cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup. The first cell is in the first cell subgroup and the configuration is associated with an identity of the first cell subgroup.

[0149] In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup, the cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup, the first cell is in the first cell subgroup, the source cell is in the first cell subset, and the target cell is in the second cell subset.

[0150] In some embodiments, the configuration is associated with at least one of a priority or a scheduling of the first uplink control transmission.

[0151] In some embodiments, the circuitry may be configured to determine the second cell in accordance with a determination that the first downlink transmission is dynamically scheduled by determining the second cell based on an indication in downlink control information received from the network device for the first downlink transmission. In some embodiments, the circuitry may be further configured to cancel the first uplink control transmission in accordance with a determination that the first downlink transmission is semi-persistently scheduled.

[0152] In some embodiments, the circuitry may be configured to determine the second cell according to a determination that the first downlink transmission is a retransmission of a semi-persistently scheduled downlink data transmission or is for a release of a semi-persistent scheduling configuration by determining the second cell based on an indication in the downlink control information.

[0153] In some embodiments, the circuitry may be configured to determine the second cell in accordance with a determination that the first downlink transmission is for at least one of an initial one of semi-persistently scheduled downlink data transmissions, a retransmission of a semi-persistently scheduled downlink data transmission, or a release of a semi-persistent scheduling configuration by determining the second cell based on an indication in the downlink control information. In some embodiments, the circuitry may be further configured to cancel the first uplink control transmission in accordance with a determination that the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information.

[0154] In some embodiments in which the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information and the first uplink control transmission and the second uplink control transmission for the second HARQ feedback for the dynamically scheduled downlink data transmission are transmitted in the same slot, the circuitry may be further configured to multiplex the first HARQ feedback into the second uplink control transmission and cancel the first uplink control transmission.

[0155] In some embodiments, the circuitry may be configured to determine the second cell by: determining whether a first uplink control transmission in the slot or sub-slot at a source cell having a first priority is available in accordance with the determination that the first downlink transmission is a semi-persistently scheduled downlink data transmission; determining whether a target cell of a second priority is present in the cell set having sufficient valid symbols for the first uplink transmission in the slot or sub-slot in accordance with the determination that the first uplink control transmission at the source cell is unavailable; and determining the target cell as the second cell in accordance with the determination that the target cell is present in the cell set, where the first priority is higher than the second priority.

[0156] In some embodiments, the circuitry may be further configured to delay the first uplink control transmission at the source cell in accordance with determining that the target cell is not in the cell set.

[0157] In some embodiments, the circuitry may be configured to determine whether a first uplink control transmission in the slot or sub-slot at a source cell having a first priority is available, and, pursuant to a determination that the first uplink control transmission at the source cell is unavailable, determine a second cell of a second priority from the set of cells that has sufficient valid symbols for the first uplink control transmission in the slot or sub-slot, where the first priority is higher than the second priority.

[0158] In some embodiments, the circuitry may be further configured to receive from the network device a configuration indicating that delaying HARQ feedback for a semi-persistently scheduled downlink data transmission in an uplink control transmission in the cell is effective when an uplink control transmission is unavailable in the cell, and to delay the first uplink control transmission in the source cell in accordance with a determination that the first downlink transmission is a semi-persistently scheduled downlink data transmission and the first uplink control transmission in the source cell is unavailable.

[0159] In some embodiments, the circuitry may be configured to: generate a final uplink transmission by multiplexing or prioritizing the first uplink control transmission and the uplink transmission in accordance with a determination that the first uplink control transmission at the source cell overlaps in the time domain with the uplink transmission; and determine whether the first uplink control transmission at the source cell is available in accordance with a determination that the final uplink transmission is unavailable by determining whether the first uplink control transmission at the source cell is available.

[0160] In some embodiments in which the first uplink control transmission in the second cell overlaps in the time domain with the uplink data transmission, the circuitry may be further configured to multiplex the first HARQ feedback into the uplink data transmission and cancel the first uplink control transmission.

[0161] In some embodiments in which the first uplink control transmission in the second cell overlaps in the time domain with a third uplink control transmission having uplink control information, the circuitry may be further configured to perform one of: determining that an error has occurred; performing the first uplink control transmission while canceling the third uplink control transmission; performing the first uplink control transmission and the third uplink control transmission simultaneously; or multiplexing the uplink control information into the first uplink control transmission while canceling the third uplink control transmission.

[0162] In some embodiments, the network device includes circuitry configured to: transmit a first downlink transmission in a first cell in a cell group to a terminal device at the network device, and receive a first HARQ feedback for the first downlink transmission from the terminal device at a second cell, the second cell being determined from a cell set for uplink control transmissions associated with the cell group.

[0163] In some embodiments, the circuitry may be further configured to transmit a configuration to the terminal device indicating that a change from execution in a source cell in the cell set to execution in a target cell in the cell set is valid for the first uplink control transmission.

[0164] In some embodiments, the configuration is terminal device specific. In some embodiments, the cell group includes a first cell subgroup and a second cell subgroup, the cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup. The first cell is in the first cell subgroup and the configuration is associated with an identity of the first cell subgroup.

[0165] In some embodiments where the cell group includes a first cell subgroup and a second cell subgroup, the cell set includes a first cell subset associated with the first cell subgroup and a second cell subset associated with the second cell subgroup, where the first cell is in the first cell subgroup, the source cell is in the first cell subset, and the target cell is in the second cell subset.

[0166] In some embodiments, the configuration is associated with at least one of a priority or a scheduling of the first uplink control transmission.

[0167] In some embodiments in which the first downlink transmission is a semi-persistently scheduled downlink data transmission without downlink control information, the circuitry may be configured to receive the first HARQ feedback by receiving a second uplink control transmission from the terminal device into which the first HARQ feedback is multiplexed, and obtaining the first HARQ feedback from the second uplink control transmission, the second uplink control transmission being for the second HARQ feedback for the dynamically scheduled downlink data transmission.

[0168] In some embodiments, the circuitry may be further configured to transmit a configuration to the terminal device indicating that, when an uplink control transmission is unavailable in the cell, delaying HARQ feedback for semi-persistently scheduled downlink data transmissions in an uplink control transmission in the cell is effective.

[0169] In some embodiments, the circuitry may be further configured to receive the first HARQ feedback by at least one of simultaneously receiving a first uplink control transmission and a third uplink control transmission having uplink control information from the terminal device, or receiving a first uplink control transmission from the terminal device in which the uplink control information is multiplexed.

[0170] The term "circuitry" as used herein may refer to hardware circuits and / or a combination of hardware circuits and software. For example, a circuit may be a combination of analog and / or digital hardware circuits and software / firmware. As a further example, a circuit may be any portion of a hardware processor with software, such as a digital signal processor, software, and memory that work together to perform various functions on a device, such as a terminal device or a network device. In yet another example, a circuit may be a hardware circuit and / or processor, such as a microprocessor or a portion of a microprocessor, that requires software / firmware for operation, but the software may not be present when not required for operation. As used herein, the term circuitry also encompasses merely a hardware circuit or processor, or a portion of a hardware circuit or processor, and its (or their) accompanying software and / or firmware implementation.

[0171] In general, various embodiments of the present disclosure may be implemented by hardware or dedicated circuits, software, logic, or any combination thereof. Some aspects may be implemented by hardware, and other aspects may be implemented by firmware or software that may be executed by a controller, microprocessor, or other computing device. Various aspects of the embodiments of the present disclosure have been shown and described as block diagrams, flow charts, or illustrated by some other pictorial representation, and it will be understood that the blocks, apparatus, systems, techniques, or methods described herein may be implemented by, for example, but not limited to, hardware, software, firmware, dedicated circuits or logic, general-purpose hardware or controller or other computing device, or combinations thereof.

[0172] The present disclosure further provides at least one computer program product tangibly stored in a computer readable non-transitory storage medium. The computer program product includes computer executable instructions, such as instructions included in program modules. The instructions execute on a target real or virtual processor device to perform, for example, the processes or methods described above with reference to Figures 3A-9. Typically, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or split among program modules as appropriate. The machine readable instructions of the program modules may be executed in local or distributed devices. In distributed devices, the program modules may be located in both local and remote storage media.

[0173] The program codes for carrying out the methods of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general purpose computer, a special purpose computer or other programmable data processing apparatus, and when the program codes are executed by the processor or controller, the functions / operations specified in the flowcharts and / or block diagrams are performed. The program codes may run entirely on the machine, partially on the machine, as a separate software package, partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0174] The above program code may be embodied on a machine-readable medium, which may be any tangible medium that contains or stores a program for use by or in conjunction with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. The machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination of the foregoing. Even more specific examples of machine-readable storage media include one or more wires, a portable computer diskette, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable-programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0175] It should be understood that although operations have been described in a particular order, it is not required that such operations be performed in the particular order or sequence shown, or that all of the operations shown be performed, in order to achieve desired results. In some situations, multitasking and parallel processing may be advantageous. Similarly, although the above discussion includes some specific implementation details, these should not be construed as limitations on the scope of the disclosure, but rather as descriptions of features that may be specific to certain embodiments. Some features that are described in the context of individual embodiments may be implemented in combination in an embodiment. Conversely, various features that are described in the context of an embodiment may be implemented in multiple embodiments separately or in any suitable subcombination.

[0176] Although the present disclosure has been described in language specific to structural features and / or methodological acts, it is to be understood that the present disclosure, as defined by the appended claims, is not necessarily limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method for a user equipment (UE), comprising: receiving a radio resource control (RRC) message from a network, the RRC message including first information for a plurality of physical uplink control channel (PUCCH) cells; The first information is information for PUCCH cell switching, determining a slot and a corresponding cell based on the first information for PUCCH transmission; the determination is a Semi-Persistent Scheduling (SPS) Physical Downlink Shared Channel (PDSCH) Hybrid Automatic Repeat Request-Acknowledgement (HARQ-ACK) procedure; The UE transmits a PUCCH including a HARO-ACK of the SPS PDSCH in the cell; method.

2. receiving downlink control information (DCI) including an indicator indicating a cell for a second PUCCH transmission when the PUCCH cell switching is applicable; Transmitting a second PUCCH in a secondary cell (SCell) indicated by the indicator of the DCI. The method of claim 1.

3. The cell is either a primary cell (PCell) or a secondary cell (SCell) for PUCCH. The method of claim 1.

4. means for receiving a radio resource control (RRC) message from a network, the RRC message including first information for a plurality of physical uplink control channel (PUCCH) cells; means for determining a slot and a corresponding cell based on the first information for PUCCH transmission; The first information is information for PUCCH cell switching, the determination is a Semi-Persistent Scheduling (SPS) Physical Downlink Shared Channel (PDSCH) Hybrid Automatic Repeat Request-Acknowledgement (HARQ-ACK) procedure; Further comprising a means for transmitting a PUCCH including a HARO-ACK of the SPS PDSCH in the cell. User Equipment (UE).

5. A means for receiving downlink control information (DCI) including an indicator indicating a cell for a second PUCCH transmission when the PUCCH cell switching is applicable; and means for transmitting a second PUCCH in a secondary cell (SCell) indicated by the indicator of the DCI; Further comprising: A user terminal according to claim 4.

6. The cell is either a primary cell (PCell) or a secondary cell (SCell) for PUCCH. A user terminal according to claim 4.

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