Side link feedback resource allocation

Abstract

A method is provided for allocating resources of a resource pool for a UE for PSFCH transmission. The method includes configuring at least one PSFCH resource set in the resource pool, which consists of one or more time-frequency resources for the PSFCH transmission. The step of configuring the at least one PSFCH resource set in the resource pool may include configuring the at least one PSFCH resource set to be specific to one or more PSFCH formats. The step of configuring the at least one PSFCH resource set in the resource pool may include configuring the set to consist of time-frequency resources (including periods, time slot period offsets, and time gaps between PSFCH and associated PSSCH) for the PSFCH transmission.

Description

Technical Field

[0001] The following disclosure relates to resource allocation for sidelink feedback transmission in cellular communication networks. Background Technology

[0002] Wireless communication systems such as third-generation (3G) mobile phone standards and technologies are well-known. These 3G standards and technologies were developed by the 3rd Generation Partnership Project (3GPP). Third-generation wireless has generally been developed to support macrocellular mobile phone communication. Communication systems and networks have evolved towards broadband and mobile systems.

[0003] In a cellular wireless communication system, a user equipment (UE) connects to a radio access network (RAN) via a radio link. The RAN comprises a set of base stations that provide radio links to UEs located in cells covered by base stations, and an interface that provides overall network control to the core network (CN). As will be appreciated, the RAN and CN each perform corresponding functions relative to the overall network. For convenience, the term "cellular network" will be used to refer to the combined RAN and CN, and it will be understood that the term is used to refer to the respective systems used to perform the disclosed functions.

[0004] The 3G Partnership has developed what is known as Long Term Evolution (LTE) systems (i.e., Evolved Universal Mobile Telecommunications System Territorial Radio Access Network (E-UTRAN)) for mobile access networks, where one or more macro cells are supported by base stations called eNodeBs or eNBs (evolved NodeBs). More recently, LTE has further evolved into what is known as 5G or NR (New Radio) systems, where one or more cells are supported by base stations called gNBs. NR is proposed to utilize the Orthogonal Frequency Division Multiplexing (OFDM) physical transport format.

[0005] In traditional cellular communication networks, even when mobile devices are within each other's wireless communication range, all signaling occurs between each mobile device and the base station, rather than directly between the mobile devices. This can lead to inefficient use of wireless transmission resources and potentially increase base station resource utilization. Sidelink communication allows mobile devices to communicate directly rather than via base stations, potentially improving both wireless and base station resource utilization. Sidelink communication is considered particularly interesting for machine-to-machine communication (specifically, vehicle-to-vehicle (V2V) and vehicle-to-everything / anything (V2X) communication). Summary of the Invention

[0006] The present invention provides a selection of concepts to introduce a simplified form, which are further described in the detailed description below. This invention is not intended to identify key or essential features of the claimed subject matter, nor is it intended to be used as an aid in determining the scope of the claimed subject matter.

[0007] A method is provided for allocating resources of a resource pool for a UE for PSFCH transmission, the method comprising configuring at least one set of PSFCH resources in a resource pool consisting of one or more time-frequency resources for PSFCH transmission.

[0008] The step of configuring the at least one PSFCH resource set in the resource pool may include configuring the at least one PSFCH resource set as specific to a single or more PSFCH formats.

[0009] The step of configuring the at least one PSFCH resource set in a resource pool may include configuring the set to consist of time-frequency resources for PSFCH transmission, the time-frequency resources including a time slot period, a time slot period offset, and a time gap between the PSFCH resources and associated PSSCH resources. Configuring the at least one PSFCH resource set in a resource pool may include configuring the set to support frequency hopping.

[0010] A method is also provided for multiplexing PSFCH resources used for different PSFCH transmissions onto at least one PSFCH resource set.

[0011] The process of reusing PSFCH resources may include using an implicit mapping between the PSFCH resources and the associated PSCCH / PSSCH resources. This implicit mapping may include setting a PSFCH resource offset within the PSFCH resource set that is equal to the sub-channel number of the first sub-channel of the associated PSCCH / PSSCH resource.

[0012] The process of reusing PSFCH resources may include explicit signaling using the PSFCH resources. PSFCH resources can be dynamically signaled during DCI / SCI transport.

[0013] The steps of reusing PSFCH resources may include dynamic signaling using PSFCH resource offsets. The steps of reusing PSFCH resources may include using a configurable PSFCH resource multiplexing scheme for each resource pool. The steps of reusing PSFCH resources for different PSFCH transmissions may include allowing the UE to transmit multiple PSFCH transmissions in a single time slot.

[0014] A method for allocating resources of a resource pool for a UE for PSFCH transmission is also provided, the method comprising: configuring at least one PSFCH resource set in a resource pool consisting of one or more time-frequency resources for PSFCH transmission; wherein the time-frequency resources are time-frequency continuous or discontinuous; wherein configuring at least one PSFCH resource set in the resource pool comprises configuring the set together with the configuration of the resource pool.

[0015] The options for optional features are listed in the dependent claims.

[0016] Non-transient computer-readable media may include at least one from the group consisting of hard disks, CD-ROMs, optical storage devices, magnetic storage devices, read-only memory, programmable read-only memory, erasable programmable read-only memory, EPROM, electrically erasable programmable read-only memory, and flash memory. Attached Figure Description

[0017] Further details, aspects, and embodiments of the invention will be described by way of example only with reference to the accompanying drawings. Elements shown in the drawings are illustrated for simplicity and clarity and are not necessarily drawn to scale. For ease of understanding, the same reference numerals have been included in the corresponding drawings.

[0018] Figure 1 A schematic diagram of a cellular network is shown.

[0019] Figure 2 An example of a side link slot structure in which PSFCH resources are multiplexed with PSCCH / PSSCH resources is shown.

[0020] Figure 3 An example of inter-slot PSFCH resource allocation for two resource pools is shown.

[0021] Figure 4 An example of a PFSCH resource set with different periods and period offsets is shown.

[0022] Figure 5 An example of frequency hopping for the PFSCH resource set is shown.

[0023] Figure 6 Examples of possible PSFCH resource sets with different time-frequency configurations are shown.

[0024] Figure 7 An example configuration of the PSFCH resource set is shown.

[0025] Figure 8 An example of PSFCH resource reuse using an implicit mapping between PSFCH resources and associated PSCCH / PSSCH resources is shown.

[0026] Figure 9 An example of PSFCH resource multiplexing using an implicit mapping between PSFCH resources and associated PSCCH / PSSCH resources is shown by setting the PSFCH resource offset to be equal to the first sub-channel number of the associated PSCCH / PSSCH resource.

[0027] Figure 10An example of PSFCH resource multiplexing via explicit signaling of PSFCH resource offset is shown.

[0028] Figure 11 An example of PSFCH multiplexing in which PSFCH resources are configured for unicast transmission in every 2 time slots is shown.

[0029] Figure 12 An example of PFSCH resource reuse with a period of 2 is shown. Detailed Implementation

[0030] Those skilled in the art will recognize and understand that the details of the described examples are merely illustrations of some embodiments, and the teachings set forth herein can be applied to various alternative settings.

[0031] Figure 1 A schematic diagram of three base stations (e.g., eNBs or gNBs according to specific cellular standards and terminology) forming a cellular network is shown. Typically, each base station will be deployed by a cellular network operator to provide geographic coverage for UEs in that area. The base stations form a Radio Local Area Network (RAN). Each base station provides radio coverage for UEs in its area or cell. The base stations are interconnected via an X2 interface and connected to the core network via an S1 interface. As will be understood, only basic details are shown to illustrate key characteristics of the cellular network. In the proposed NR protocol, the Uu interface is between the base station and the UE. The PC5 interface is set between UEs for SideLink (SL) communication. Regarding... Figure 1 The interface and component names mentioned are for illustrative purposes only; different systems operating on the same principles may use different naming conventions.

[0032] Each base station includes the hardware and software for implementing RAN functions, including communication with the core network and other base stations, transmission of control and data signals between the core network and UEs, and maintaining wireless communication with the UEs associated with each base station. The core network includes the hardware and software for implementing network functions, such as overall network management and control, and call and data routing.

[0033] To achieve the required reliability and latency in SL communication (e.g., NR V2X communication) in such networks, a Hybrid Automatic Repeat Request (HARQ) scheme is used for SL communication. For SL communication between the transmitting UE and the receiving UE, the receiving UE receives data on the Physical Sidelink Shared Channel (PSSCH) and receives Sidelink Control Information (SCI) on the Physical Sidelink Control Channel (PSCCH). For unicast SL communication, when SL feedback is enabled, when the receiving UE successfully receives and decodes the SCI and successfully receives the associated data, the receiving UE sends a HARQ acknowledgment (HARQ-ACK) feedback to the transmitting UE via the Physical Sidelink Feedback Channel (PSFCH) as part of the Sidelink Feedback Control Information (SFCI). When the receiving UE successfully receives and decodes the SCI but fails to receive data, the receiving UE will send a HARQ negative acknowledgment (HARQ-NACK) feedback to the sending UE via PSFCH as part of the SFCI.

[0034] Sidelink transmissions use TDD (half-duplex) on dedicated carriers or on shared carriers using traditional Uu transmissions between the base station and the UE. Resource pools of transmission resources are used to manage resource allocation and to manage interference between potential concurrent transmissions. A resource pool is a set of time-frequency resources from which resources can be selected for transmission. A UE can be configured with multiple transmit and receive resource pools.

[0035] Two operating modes are proposed for resource allocation in sidelink communication. When the UE is within the coverage area of ​​the base station and the resources are allocated by the base station, the first mode (mode 1) is applied. When the UE is not within the coverage area of ​​the base station, the second mode (mode 2) is used, and the UE autonomously selects and utilizes resources, typically using pre-transmission listening processing.

[0036] The UE reserves the transmission resources by sending an SCI message indicating the resources to be used for transmission. The SCI informs the receiving end (which may be a single UE in unicast, a group of UEs in multicast, or all reachable UEs in broadcast) of the details of the transmission it can expect. The UE may reserve transmission resources for the first transmission of a data transport block (TB) and for retransmission of the TB to improve reliability in the event of an initial transmission failure.

[0037] Regarding the scheduling and procedures for SFCI communication via PSFCH, the following agreements have been reached: At least for sidelink HARQ feedback, the NR sidelink must support a PSFCH format that uses resources including one or more last symbols available for sidelink communication within the time slot. At least from the UE's transmission perspective, TDM between PSCCH / PSSCH resources and PSFCH resources is permitted. At least for the case where the PSFCH in a time slot responds to a single PSSCH, an implicit mechanism is used to at least determine the frequency and / or code domain resources within the resource pool for the PSFCH.

[0038] An example of the SL time slot structure is shown in Figure 2 In this configuration, using TDM, PSFCH resources are multiplexed with PSCCH / PSSCH resources. Note that PSFCH is not necessarily associated with PSSCH in the same time slot. If a UE is scheduled to receive on PSSCH and subsequently transmit on PSFCH, a transition period is required when switching from receiving to transmitting. Similarly, if a UE receives PSFCH communication in the same time slot as the PSSCH communication, a transition period is also required.

[0039] Regarding inter-slot resource scheduling, the following agreement has been reached. A (pre)configuration indicates the time interval between PSFCH resources and their associated PSSCH resources. Within a time slot associated with a resource pool, a PSFCH resource can be (pre)configured for N time slot periods. PSFCH resources can be (pre)configured to appear periodically in each time slot, every 2 time slots, and every 4 time slots. PSFCH resources can be (pre)configured to not appear at all. This (pre)configuration is resource pool specific. PSFCH transmissions are only transmitted within the same resource pool as the resource pool associated with the PSSCH transmission.

[0040] Figure 3 The diagram illustrates an example of inter-slot resource scheduling for PSFCH resources across two resource pools. The time slots between PSFCH resources and their associated PSSCH resources are (pre)configured (generally understood as per resource pool), meaning dynamic signaling is not supported. Resource pool 0 has PSFCH resources appearing every 2 side-link time slots (N=2), and resource pool 1 has PSFCH resources appearing every 4 side-link time slots (N=4).

[0041] Regarding the PSFCH payload (i.e., HARQ-ACK / NACK feedback), the following protocols have been established. HARQ feedback can be enabled or disabled for each UE via higher-layer signaling. HARQ feedback can also be disabled in the UE's resource pool configuration, i.e., no PSFCH resource is configured in the resource pool. In unicast communication, the HARQ payload is simple; the UE sends HARQ ACK / NACK feedback on the relevant PSFCH. In multicast transmission, the situation is more complex because feedback must be sent / received from multiple UEs. There are two options here: all UEs in the group transmission (i) only send HARQ-NACK feedback or (ii) send HARQ-ACK / NACK feedback. For option 1, all UEs share a single PSFCH resource. Since the TX-UE does not need to distinguish between UE feedbacks, all UEs can send the same HARQ-NACK feedback sequence. For option 2, each receiving UE uses a separate PSFCH resource for HARQ ACK / NACK feedback. Each PSFCH is mapped to time, frequency, and code resources.

[0042] Only a few protocols have been reached regarding the physical structure of PSFCH. A sequence-based PSFCH format with one symbol is supported. This is applicable to both unicast and multicast, including options 1 and 2 mentioned above. The sequence of PUCCH format 0 is the starting point for developing the 5G-V2X PSFCH format.

[0043] The problem with the PSFCH scheduling protocol is that only one PSFCH resource is allocated within a time slot. Another problem is that the time interval between the (pre)configured PSFCH resources and the associated PSFCH resources results in the (pre)configured minimum latency for transmission and service types with different latency requirements not being supported within a single resource pool.

[0044] A method is provided for allocating resources of a resource pool for a UE for PSFCH transmission, the method comprising configuring at least one set of PSFCH resources in a resource pool consisting of one or more time-frequency resources for PSFCH transmission.

[0045] Time-frequency resources can be continuous in time and frequency. Time-frequency resources can also be discontinuous in time and frequency. UEs can use time-frequency resources to transmit SFCI.

[0046] The step of configuring at least one PSFCH resource set in a resource pool may include configuring at least one PSFCH resource set as specific to a single PSFCH format. A PSFCH resource set specific to a single PSFCH format may consist of time-frequency resources with the same format. A PSFCH resource set specific to a single PSFCH format may consist of time-frequency resources of the same type. A PSFCH resource set specific to a single PSFCH format may consist of time-frequency resources of the same size. For example, a first PSFCH resource set may be specified for a sequence-based PSFCH format similar to PUCCH format 0, and a second PSFCH resource set may be configured for an encoded PSFCH format similar to PUCCH format 2. Configuring a PSFCH resource set as specific to a single PSFCH format facilitates implicit PSFCH multiplexing and the use of implicit signaling to indicate PSFCH resources.

[0047] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the at least one PSFCH resource set as specific to multiple PSFCH formats. Multiple different PSFCH formats of the PSFCH resource set will use the same number of symbols. Multiple different PSFCH formats can be multiplexed in the PSFCH resource set through explicit signaling of the PSFCH resources, for example, explicit signaling used to indicate frequency locations.

[0048] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to consist of time-frequency resources for PSFCH transmission, the time-frequency resources including a slot period and a slot period offset. Multiple PSFCH resource sets can be configured, each consisting of a different period and period offset. This allows, for example, a first PSFCH resource set to be available per even-numbered slots, and a second PSFCH resource set to be available per odd-numbered slots. Furthermore, the UE or its base station can schedule PSFCH transmissions requiring a large number of PSFCH resources (e.g., multicast transmissions with ACK / NACK feedback) such that PSFCH transmissions occur in slots with large PSFCH resource sets. Figure 4 An example is shown in which PSFCH0 is configured in each SL time slot (time slot period of 1), PSFCH1 is configured in each even-numbered SL time slot (time slot period of 2), and PSFCH2 is configured in each odd-numbered SL time slot (time slot period of 2, time slot period offset of 1).

[0049] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to consist of time-frequency resources for PSFCH transmission, the time-frequency resources including time slots between PSFCH resources and associated PSSCH resources. This enables service types with different latency requirements. For example, in Figure 4In this configuration, resource set PSFCH0 occurs in each time slot, thus resource set PSFCH0 has the potential to support low-latency services. If the PSSCH-PSFCH interval is configured to be 0 time slots, the UE can receive PSSCH and transmit the associated PSFCH within the same time slot (assuming sufficient UE capacity). Simultaneously, Mode-2 UEs sensing PSSCH transmissions are aware of the PSFCH resource set configuration and can implicitly infer the PSFCH resources used for the corresponding PSFCH transmission. Therefore, UE resource pools with different PSFCH resource set configurations can be shared between Mode-1 and Mode-2 users.

[0050] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to support frequency hopping according to a configurable mode. Figure 5 An example is shown where PSFCH0 is changing its frequency position with each SL time slot.

[0051] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set as UE group-specific. The base station may, for example, configure a group-specific PSFCH resource set during group configuration. The resource set can then be configured based on group feedback requirements. Multicast transmissions will then automatically use this PSFCH resource set.

[0052] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to allow CBG-based feedback. Feedback for CBG requires more PSFCH resources, so it may be beneficial to allow CBG feedback only for certain PSFCH resource sets.

[0053] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to be associated with a portion of the frequency resources within the resource pool. The PSFCH resource set may be associated with a specific frequency range within the resource pool. The PSFCH resource set may define the associated PSCCH / PSSCH frequency range. If the first allocated sub-channel for PSCCH / PSSCH is within the frequency range, the transmission uses the corresponding PSFCH resource pool for feedback. Note that multiple transmissions can be scheduled within a frequency range, and therefore they will use the same PSFCH resource set.

[0054] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set to associate PSSCH transports with the PSFCH resource set. PSSCH transports may be implicitly associated with a PSFCH resource set. PSSCH transports may be explicitly associated with a PSFCH resource set. PSSCH transports may be directly associated with a PSFCH resource set via dynamic signaling in the DCI / SCI. Dynamic signaling may include the ID of the PSFCH resource set. PSSCH transports may be implicitly associated with a PSFCH resource set via resource allocation of the associated PSSCH, for example, if the PSFCH resource set is subchannel dependent. PSSCH transports may be implicitly associated with a PSFCH resource set for transport via PSFCH format, for example, if feedback requires PSFCH format 2, then only PSFCH resource sets that allow that format are considered. PSSCH transports may be implicitly associated with a PSFCH resource set via CBG-based feedback, for example, some PSFCH resource sets may allow CBG feedback while others may not.

[0055] The step of configuring at least one PSFCH resource set in a resource pool may include configuring the set together with the configuration of the resource pool.

[0056] The method may also include configuring the resource pool to include a list of PSFCH resource sets. The list of PSFCH resource sets in the resource pool can be empty, i.e., HARQ feedback is not supported in the resource pool.

[0057] Figure 6 The example provided illustrates possible PSFCH resource sets with different time-frequency configurations. In this example, the resource set consists of contiguous time-frequency resources. A resource set can also contain a list of time-frequency resources, each configured individually like an NR PUCCH resource allocation.

[0058] Figure 7 An example of resource pool configuration is given below. Note that the PSFCH resource set is configured by sub-channel because remaining resources in the frequency domain can be used for PSSCHs allocated only at the sub-channel granularity. The sub-channel granularity is the same as that used for resource pool configuration and is therefore not part of the PSFCH resource set configuration.

[0059] As can be seen, the PSFCH resource set can be defined as a group of PSFCH time-frequency resources, which can be configured with different performance characteristics (e.g., period, period offset, PSSCH-PSFCH interval, frequency hopping, etc.). This allows for highly flexible allocation of feedback resources tailored to various requirements of new V2X services (low latency, high throughput, etc.). The proposed PSFCH resource set allows for flexible allocation of HARQ feedback resources and improves the efficiency of feedback resources in 5G side link communication.

[0060] A method is also provided for multiplexing PSFCH resources used for different PSFCH transmissions onto at least one set of PSFCH resources.

[0061] When related PSCCH / PSSCH transmissions occur on different sub-channels but in the same time slot, we first consider reusing PSFCH resources. If PSSCH transmissions are scheduled on different sub-channels in the same time slot, their related PSFCH feedback transmissions must also be multiplexed.

[0062] The steps for reusing PSFCH resources may include using implicit mappings between PSFCH resources and associated PSCCH / PSSCH resources.

[0063] Implicit allocation of PSFCH resources has the advantage of allowing the UE to sense the associated PSCCH / PSSCH transmissions and directly derive the location of the mapped PSFCH resources. However, implicit mapping is not resource-efficient due to its inflexibility. Implicit mapping between PSFCH resources and associated PSCCH / PSSCH resources is supported. A simple scheme is to map PSFCH resources to the first sub-channel used by the associated PSCCH / PSSCH resources. Figure 8 An example is depicted where four UEs transmit on different sub-channels. While the mapping is simple, from... Figure 8 It is clear that PSFCH resource utilization is very poor. Of the 20 available PRBs, only 4 are used for sending PSFCH transmissions.

[0064] Implicit mapping between PSFCH resources and associated PSCCH / PSSCH resources may include setting a PSFCH resource offset within the PSFCH resource set that is equal to the subchannel number of the first subchannel of the associated PSCCH / PSSCH resource.

[0065] The association between the PSFCH resource offset and the sub-channel number of the PSCCH / PSSCH transmissions within the resource set improves PSFCH resource utilization. For example, Figure 9 There are five sub-channels. UE2's first transmission is sub-channel 3, therefore the PSFCH resource offset is 3. From Figure 9 As can be observed, the PSFCH resource set requires at least 5 PRBs (more typically n) in bandwidth. subCHsize RBs 2 However, since PSFCH resource allocation is likely based on sub-channels, two sub-channels must be available. Therefore, this example uses only 4 out of 8 PSFCH resources. This scheme is efficient if a large number of transmissions are scheduled, with each transmission occupying only a small number of sub-channels. Conversely, it is less efficient if only a small number of transmissions are scheduled across multiple sub-channels.

[0066] The process of reusing PSFCH resources may include explicit signaling using the PSFCH resources. PSFCH resources can be signaled during DCI / SCI transport.

[0067] Dynamic signaling is highly effective, but it comes with signaling overhead and the fact that the UE needs to decode control information to know the exact location of the PSFCH resource. To improve resource efficiency, it should be done as follows: Figure 10 The PSFCH resources are allocated as shown. In this example, the PSFCH resources for all four transmissions can be allocated to only 4 PRBs. The remaining resources can be used, for example, to schedule PSSCH resources (if no half-duplex issues occur) or to configure another set of PSFCH resources. In example UE0, assuming UE1 and UE2 send feedback in another time slot, UE1 and UE2 can use the last two symbols for PSSCH resources. To achieve this scheme, the offset must be associated with each transmission. Figure 10 In the example, a PSFCH resource set is allocated across PRB0 to PRB3 in the sub-channel. The offset can be relative to the first PRB of the PSFCH resource set; that is, UE0, UE1, UE2, and UE3 have offsets of 0, 1, 2, and 3 PRBs, respectively. To address each PSFCH resource in this resource set example, 2 bits are required. Typically, the number of bits for the PSFCH resource offset is given by the following formula:

[0068]

[0069] Where, n subCHsize It is the size of the sub-channel. It is the sub-channel number of the PSFCH resource set. It is the number of PRBs for each PSFCH resource.

[0070] Clearly, the larger the PSFCH resource set, the more bits are needed for offsets. To achieve optimal multiplexing, offsets need to be dynamically signaled, as the number of transmissions and their bandwidth can change for each time slot.

[0071] The process of reusing PSFCH resources may include dynamic signaling using PSFCH resource offsets. PSFCH resource offsets can be dynamically signaled during DCI / SCI transport.

[0072] The process of reusing PSFCH resources may include using a configurable PSFCH resource multiplexing scheme for each resource pool. Depending on the nature of communication within the resource pool, implicit or explicit signaling of PSFCH resources can be beneficial. Therefore, it is desirable to configure a multiplexing scheme for each resource pool.

[0073] We now discuss PSFCH resource reuse for transmissions occurring in different time slots.

[0074] The step of reusing PSFCH resources for different PSFCH transmissions may include allowing the UE to transmit multiple PSFCH transmissions in a single time slot.

[0075] If the PSFCH period N>1, then the feedback from transmissions in different time slots needs to be multiplexed onto the PSFCH resource in one time slot. Figure 11 A simplified example of PSFCH multiplexing is depicted, where PSFCH resources are configured for unicast transmission every two time slots. We assume that the time slots between PSSCH resources and associated PSFCH resources are configured to be two time slots, i.e., the earliest feedback of PSSCH transmission in time slot n occurs in time slot n+2.

[0076] When the same UE receives PSFCH transmissions in two consecutive time slots, the UE receives the transmissions in time slots n and n+1. The earliest feedback is n+2 and n+3, but since there are no PSFCH resources in time slot n+2, feedback for both transmissions must be sent in time slot n+3. The UE can send HARQ-ACK feedback on a separate PSFCH resource. This requires the UE to be able to send multiple PSFCHs in the same time slot. Alternatively, the UE can send HARQ-ACK feedback for two transmissions on the same PSFCH resource. This requires the PSFCH to be able to carry multiple bits. PUCCH format 0 only carries 2 bits, so it is insufficient for N>2. Therefore, it is necessary to allow the UE to transmit multiple PSFCH transmissions in one time slot.

[0077] When PSSCH transmissions are received by two different UEs in two consecutive time slots, the two transmissions can use the same PSSCH resources, but each UE needs to know the sequence to be transmitted so that they do not interfere with each other.

[0078] The steps for multiplexing PSFCH resources used for different PSFCH transmissions in different time slots can follow rule n. PSFCH= n mod N, where N is the period of the PSFCH resource, n PSFCH It is the PSFCH resource index, and n is the number of time slots in which the relevant PSSCH is received.

[0079] The preceding section addressed the issue of multiplexing PSFCH resources for PSFCH transmission in different time slots or different sub-channels. However, typically, the PSFCH resource set can be configured with N>1 and support multiple PSFCH transmissions per time slot; that is, the resource pool consists of more than one sub-channel.

[0080] Figure 12 An example of PSFCH resource multiplexing with N=2 is shown. The mapping rules given above for multiplexing different transmissions in different time slots are combined with different methods for sub-channel to PSFCH resource mapping. Scheme S1 uses direct sub-channel mapping rules, while Scheme S2 uses first sub-channel to PSFCH resource rules. Scheme S3 is a dynamic scheme with signaling of PSFCH offset. It can be observed that implicit mapping results in segmented PSFCH transmissions, i.e., the UE needs to send multiple PSFCHs in non-adjacent PRBs. This is undesirable because it can lead to interference from in-band emission. However, implicit mapping of sub-channel numbers to PSFCH resources is more resource efficient and results in fewer segments. Note that if N is greater than the sub-channel size, the mapping rules in S2 need to be modified. In this case, multiplexing scheme S1 is preferable. Dynamic signaling with only PSFCH resource offset can achieve high resource efficiency and allow for continuous PSFCH resources for each UE. Therefore, we recommend extending the dynamic signaling of offset to the case N>1.

[0081] When the period of a PSFCH resource is greater than 1, multiplexing PSFCH resources may include dynamic signaling using PSFCH resource offsets. This may include introducing offset parameters that address different PSFCH resources within a PSFCH resource set to map PSFCH resources to the PSFCH resource set. The offset parameters may be signaled in the DCI / SCI of the scheduled transport.

[0082] The smallest granularity of the offset parameter is the smallest frequency allocation of PSFCH resources (e.g., a PRB), but this would result in high control overhead and is also unnecessary. In PFSCH resource multiplexing, a UE's PSFCH transmissions can be adjacent. This minimizes in-band spurious emissions. Therefore, a UE's PSFCH resources in consecutive time slots are mapped to adjacent PRBs in the PFSCH resource set.

[0083] The number of offsets N is limited by the size of the PSFCH resource set. offset :

[0084]

[0085] Where, n subCHsize It is the size of the sub-channels in the resource pool. N and N are the subchannel number and period of the PSFCH resource set, respectively. Offset L should have granularity for the PSFCH resource bandwidth with respect to L = N.

[0086] Only one parallel transmission is allowed in the resource pool, equal to the number of sub-channels in the resource pool. Therefore, the PSFCH resources must be equal to the number of sub-channels. Figure 12 In this configuration, there are 5 sub-channels and N=2, therefore the PSFCH resource set should consist of 10 (5×2=10) PSFCH resources. Thus, 5 offsets are needed: 0, 2, 4, 6, and 8.

[0087] A special case is multicast transmissions with ACK / NACK feedback. In multicast transmissions, a transmission is always sent to a group of users, but each user is required to send feedback on the PSFCH resource. It has been proposed to use the UE ID within the group to derive the PSFCH resource location. In connection-based multicast, another solution could be to reserve a set of PSFCH resources for the group (as described above) and allocate dedicated PSFCH resources within that set to each group member. For example, the offset could be signaled to the UEs in the group within the PSFCH resource set.

[0088] The steps of reusing PSFCH resources may include allocating dedicated PSFCH resources to each group member during group configuration for SL multicast transports.

[0089] To avoid PSFCH conflicts with other transmissions, a dedicated PSFCH resource set is allocated to the group. This can also be applied to mixed feedback, where some users use ACK / NACK feedback while others use only NACK. When configuring the entire group with only NACK feedback, the same PSFCH multiplexing and mapping as for unicast is applied.

[0090] The advantages of the proposed method include: Resource utilization: PSFCH resources are minimized, and the freed resources can be used for different purposes. Flexibility: PSFCH resources can be configured to meet specific requirements of transmission or service. Coexistence of different services: For example, within a resource pool, two PSFCH resource sets can be configured: a smaller PSFCH resource set with high periodicity and short PSSCH-PSFCH resource intervals for low-latency services, and a larger PSFCH resource set with high multiplexing capacity, low periodicity, and large PSSCH-PSFCH intervals for high-connectivity services.

[0091] Although not shown in detail, any device or apparatus forming part of a network may include at least a processor, a storage unit, and a communication interface, wherein the processor unit, storage unit, and communication interface are configured to perform methods of any aspect of the invention. Further options and choices are described below.

[0092] The signal processing functions (specifically, gNB and UE) of embodiments of the present invention can be implemented using computing systems or architectures known to those skilled in the art. Computing systems that may be desired or suitable for a given application or environment can be used (such as desktop computers, laptops or notebook computers, handheld computing devices (PDAs, cellular phones, PDAs, etc.), mainframes, servers, clients, or any other type of specialized or general-purpose computing device). The computing system may include one or more processors, which can be implemented using general-purpose or special-purpose processing engines (e.g., microprocessors, microcontrollers, or other control modules).

[0093] The computing system may also include main memory (such as random access memory (RAM) or other dynamic memory) for storing information and instructions to be executed by the processor. This main memory may also be used to store temporary variables or other intermediate information during the execution of instructions executed by the processor. The computing system may also include read-only memory (ROM) or other static storage devices for storing static information and instructions of the processor.

[0094] The computing system may also include an information storage system, which may include, for example, media drives and removable storage interfaces. Media drives may include drives or other mechanisms for supporting fixed or removable storage media (such as hard disk drives, floppy disk drives, magnetic tape drives, optical disc drives, compact disc (CD) or digital video drive (DVD) read or write drives (R or RW), or other removable or fixed media drives). Storage media may include, for example, hard disks, floppy disks, magnetic tapes, optical discs, CDs or DVDs, or other fixed or removable media read and written by media drives. Storage media may include computer-readable storage media having specific computer software or data stored therein.

[0095] In alternative embodiments, the information storage system may include other similar components for allowing computer programs or other instructions or data to be loaded into the computing system. Such components may include, for example, removable storage units and interfaces (such as program boxes and box interfaces, removable memory (e.g., flash memory or other removable memory modules) and memory slots, as well as other removable storage units and interfaces that allow software and data to be transferred from the removable storage units to the computing system.

[0096] The computing system may also include a communication interface. This communication interface allows software and data to be transferred between the computing system and external devices. Examples of communication interfaces may include modems, network interfaces (such as Ethernet or other NIC cards), communication ports (such as a Universal Serial Bus (USB) port), PCMCIA slots and cards, etc. Software and data transmitted via the communication interface may be in the form of electrical, electromagnetic, and optical signals, or other signals that can be received by the communication interface medium.

[0097] In this document, the terms "computer program product," "computer-readable medium," etc., are generally used to refer to tangible media such as memory, storage devices, or storage units. These and other forms of computer-readable media may store one or more instructions for use by a processor, including a computer system, to cause the processor to perform specified operations. Such instructions, commonly referred to as "computer program code" (which may be grouped as computer programs or other groups), when executed, enable a computing system to perform the functions of embodiments of the present invention. Note that code may directly cause a processor to perform specified operations, be compiled to perform specified operations, and / or be combined with other software, hardware, and / or firmware elements (e.g., libraries for performing standard functions) to perform specified operations.

[0098] Non-transient computer-readable media may include at least one from the group consisting of hard disks, CD-ROMs, optical storage devices, magnetic storage devices, read-only memories, programmable read-only memories, erasable programmable read-only memories, EPROMs, electrically erasable programmable read-only memories, and flash memory. In embodiments using software-implemented elements, the software may be stored in the computer-readable medium and loaded into a computing system using, for example, a removable storage drive. When executed by a processor in the computer system, a control module (in this example, software instructions or executable computer program code) causes the processor to perform the functions of the invention described herein.

[0099] Furthermore, the concepts of this invention can be applied to any circuit used to perform signal processing functions within a network element. It is further envisioned that, for example, semiconductor manufacturers can incorporate these concepts into the design of standalone devices such as microcontrollers or application-specific integrated circuits (ASICs) and / or any other subsystem elements.

[0100] It will be understood that, for clarity, the above description has referred to embodiments of the invention with reference to a single processing logic. However, the inventive concept can be similarly implemented by multiple different functional units and processors for providing signal processing functions. Therefore, references to specific functional units are to be regarded only as references to suitable means for providing said functions, and not as indications of strict logical or physical structure or organization.

[0101] The aspects of the invention can be implemented in any suitable form, including hardware, software, firmware, or any combination thereof. The invention can optionally (at least in part) be implemented as computer software running on one or more data processors and / or digital signal processors or configurable modular components such as FPGA devices.

[0102] Therefore, the elements and components of embodiments of the present invention can be implemented physically, functionally, and logically in any suitable manner. In fact, functionality can be implemented in a single unit, in multiple units, or as part of other functional units. While the invention has been described in conjunction with some embodiments, it is not intended to be limited to the specific forms set forth herein. Rather, the scope of the invention is limited only by the appended claims. Furthermore, although features may appear to be described in conjunction with specific embodiments, those skilled in the art will recognize that various features of the described embodiments can be combined according to the invention. In the claims, the term "comprising" does not exclude the presence of other elements or steps.

[0103] Furthermore, although listed separately, multiple means, elements, or method steps can be implemented, for example, by a single unit or processor. Additionally, while individual features may be included in different claims, these features can be advantageously combined, and their inclusion in different claims does not imply that such combinations are infeasible and / or disadvantageous. Moreover, including a feature in one class of claims does not imply limitation of that class, but rather indicates that the feature is equally applicable to other claim classes where appropriate.

[0104] Furthermore, the order of features in the claims does not imply that the features must be performed in any particular order. Specifically, the order of the steps in the method claims does not imply that the steps must be performed in that order. Rather, the steps can be performed in any suitable order. Additionally, singular references do not exclude multiple instances. Therefore, references to “a,” “an,” “first,” “second,” etc., do not exclude multiple instances.

[0105] While the invention has been described in conjunction with some embodiments, it is not intended to be limited to the specific forms set forth herein. Rather, the scope of the invention is limited only by the appended claims. Furthermore, although features may appear to be described in conjunction with specific embodiments, those skilled in the art will recognize that various features of the described embodiments can be combined according to the invention. In the claims, the terms "comprising" or "including" do not exclude the presence of other elements.

Claims

1. A method for allocating resources of a resource pool for a UE for PSFCH transmission, the method comprising: Configure at least one PSFCH resource set in the resource pool consisting of one or more time-frequency resources for PSFCH transmission; Wherein, the time-frequency resources may be continuous or discontinuous in time and frequency; The step of configuring the at least one PSFCH resource set in the resource pool includes: configuring the set together with the configuration of the resource pool. The characteristic feature is that each PSFCH resource set consists of different periods and period offsets, wherein the number of offsets N offset It is determined by the following formula: Where, n subCHsize It is the size of the sub-channels in the resource pool. N and N are the sub-channel number and period of the PSFCH resource set, respectively.

2. The method according to claim 1, characterized in that, The PSFCH resource set is related to the frequency range within the resource pool and includes a set of PRBs.

3. The method according to claim 1, characterized in that, The step of configuring the at least one PSFCH resource set in the resource pool includes: configuring the at least one PSFCH resource set to consist of time-frequency resources for PSFCH transmission, such that there is a time gap between the PSFCH resources and the associated PSSCH resources.

4. The method according to claim 3, characterized in that, The time gap between the PSSCH resource and the associated PSFCH resource is defined as the number of time gaps.

5. The method according to claim 4, characterized in that, The number of time slots is 0 or 2.

6. The method according to claim 1, characterized in that, PSFCH resources used for different PSFCH transmissions are multiplexed into the at least one PSFCH resource set, wherein the multiplexing includes mapping the PSFCH resources to associated PSCCH / PSSCH resources, and the mapping includes setting a PSFCH resource offset within the PSFCH resource set to be equal to the sub-channel number of the first sub-channel of the associated PSCCH / PSSCH resource.

7. The method according to claim 1, characterized in that, The at least one PSFCH resource set consists of the number of sub-channels multiplied by the PSFCH period.

8. The method according to claim 6, characterized in that, The steps for reusing PSFCH resources include: allowing the UE to transmit multiple PSFCH transmissions in one time slot.

9. The method according to claim 1, characterized in that, The step of configuring the at least one PSFCH resource set in the resource pool includes: configuring the at least one PSFCH resource set to support frequency hopping according to a configurable mode.

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