Device for transmitting and receiving a physical sidelink feedback channel in a wireless communication system

Abstract

A terminal and an operating method of the terminal are provided. The terminal is configured to perform vehicle-to-everything (V2X) communication in a wireless communication system, and the operating method includes signaling a maximum physical sidelink feedback channel (PSFCH) reception capability to a base station; and receiving a wireless signal transmitted from the base station based on the maximum PSFCH reception capability, where the maximum PSFCH reception capability is the maximum number of PSFCHs that can be received within one transmission time interval (TTI).

Description

[0001] Cross-reference to Related Applications

[0002] This application claims priority to U.S. Provisional Application No. 62 / 977,430, filed on February 17, 2020, U.S. Provisional Application No. 63 / 024,098, filed on May 13, 2020, and Korean Patent Application No. 10-2020-0096942, filed on August 3, 2020, the entire disclosures of which are incorporated herein by reference. Technical Field

[0003] The present disclosure relates to an apparatus and method for efficiently transmitting and receiving a physical sidelink feedback channel (PSFCH) to perform vehicle-to-everything (V2X) communication in a wireless communication system. Background Art

[0004] To meet the growing demand for wireless data traffic after the commercialization of fourth-generation (4G) communication systems, efforts have been made to develop fifth-generation (5G) communication systems.

[0005] Accordingly, 5G communication systems have recently been commercialized. To achieve high data transmission rates, 5G communication systems may be implemented in ultra-high frequency bands (e.g., millimeter wave (mmWave) bands or, for example, 60 gigahertz (GHz) bands). To reduce the path loss of radio waves and increase the distance that radio waves propagate in ultra-high frequency bands, beamforming techniques, massive multiple-input multiple-output (MIMO) techniques, full-dimensional MIMO (FD-MIMO) techniques, array antennas, analog beamforming techniques, and large-scale antenna techniques have been or will be applied to 5G communication systems.

[0006] In addition, to improve the networks of communication systems, techniques such as evolved small cells, advanced small cells, cloud radio access networks (cloud RANs), ultra-dense networks, device-to-device communication (D2D), wireless backhaul, mobile networks, cooperative communication, coordinated multi-point (CoMP), and received interference cancellation have been or will be applied to 5G communication systems.

[0007] In addition, advanced coding modulation (ACM) techniques such as hybrid frequency shift keying and quadrature amplitude modulation (FQAM) and sliding window superposition coding (SWSC), as well as advanced access techniques such as filter bank multi-carrier (FBMC), non-orthogonal multiple access (NOMA), and sparse code multiple access (SCMA) have been or will be applied to 5G communication systems.

[0008] In addition, different from long-term evolution (LTE) V2X communication that only supports broadcasting, unicast and multicast are also supported in the new radio (NR) V2X communication of Release 16 (Rel-16). In addition, the physical sidelink feedback channel (PSFCH) has been newly defined to improve the reliability of unicast and multicast. Therefore, a transmitting terminal (e.g., a terminal configured to transmit a signal and / or a channel) can receive acknowledgement / negative-acknowledgement (ACK / NACK) feedback from a receiving terminal (e.g., a terminal configured to receive a signal and / or a channel) through the PSFCH, and thus, hybrid automatic repeat request (HARQ) can be enabled.

[0009] As a reference, a low peak-to-average power ratio (PAPR) sequence based on the Zadoff-Chu sequence can be applied to the PSFCH, and the 1-bit HARQ-ACK / NACK included in the PSFCH can have the above sequence format. In addition, the PSFCH can be transmitted in units of 1 resource block (RB), and code division multiplexing (CDM) can be applied to the PSFCH so that multiple users (or terminals) can transmit the PSFCH through one RB.

[0010] However, since the transmitting terminal can receive HARQ ACK / NACK from multiple receiving terminals simultaneously in a multicast mode, as the number of receiving terminals included in a group increases, the number of PSFCHs to be received by the transmitting terminal may increase. However, since the maximum number of PSFCHs that a terminal can receive is not defined in the current 3rd Generation Partnership Project (3GPP) standard, the number of received PSFCHs may exceed the PSFCH reception capability of the transmitting terminal depending on the situation. In addition, since the transmitting terminal must determine whether all PSFCHs received from multiple receiving terminals are ACK or NACK, the operation of determining whether a PSFCH is ACK or NACK may increase the workload of the transmitting terminal. SUMMARY OF THE INVENTION

[0011] Devices and methods are provided for efficiently transmitting and receiving a Physical Sidelink Feedback Channel (PSFCH) to perform Vehicle-to-Everything (V2X) communication in a wireless communication system.

[0012] Additional aspects will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the presented embodiments.

[0013] According to an aspect of the present disclosure, an operating method of a terminal configured to perform Vehicle-to-Everything (V2X) communication in a wireless communication system includes: signaling a maximum Physical Sidelink Feedback Channel (PSFCH) reception capability to a base station, wherein the maximum PSFCH reception capability is the maximum number of PSFCHs that can be received during one Transmission Time Interval (TTI).

[0014] According to an aspect of the present disclosure, an operating method of a terminal configured to perform Vehicle-to-Everything (V2X) communication in a wireless communication system includes: signaling a maximum Physical Sidelink Feedback Channel (PSFCH) transmission capability to a base station, wherein the maximum PSFCH transmission capability is the maximum number of PSFCHs that can be transmitted during one Transmission Time Interval (TTI).

[0015] According to an aspect of the present disclosure, a terminal configured to perform Vehicle-to-Everything (V2X) communication includes: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to control the transceiver to send signaling for a maximum Physical Sidelink Feedback Channel (PSFCH) reception capability to a base station, wherein the maximum PSFCH reception capability is the maximum number of PSFCHs that can be received during one Transmission Time Interval (TTI).

[0016] According to one aspect of the present disclosure, a terminal configured to perform vehicle-to-everything (V2X) communication includes: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to control the transceiver to send signaling for the maximum physical sidelink feedback channel (PSFCH) transmission capability to a base station, where the maximum PSFCH transmission capability is the maximum number of PSFCHs that can be transmitted during one transmission time interval (TTI).

[0017] According to one aspect of the present disclosure, a terminal configured to perform vehicle-to-everything (V2X) communication includes: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to: control the transceiver to measure the reference signal received power (RSRP) or signal-to-interference-plus-noise ratio (SINR) of k PSFCHs among a plurality of physical sidelink feedback channels received during one transmission time interval (TTI), where k is an integer greater than 1; sort the k PSFCHs in ascending order based on the RSRP or the SINR; control the transceiver to perform an order determination that the k PSFCHs sorted in ascending order are hybrid automatic repeat request (HARQ) acknowledgments (ACK) or HARQ negative acknowledgments (NACK); and determine whether to retransmit a physical sidelink shared channel (PSSCH) based on the order determination.

[0018] According to one aspect of the present disclosure, a terminal configured to perform vehicle-to-everything (V2X) communication includes: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to control the transceiver to measure the reference signal received power (RSRP) or signal-to-interference-plus-noise ratio (SINR) of a plurality of physical sidelink feedback channels (PSFCHs) received during one transmission time interval (TTI); select k PSFCHs that meet a preset criterion from the plurality of PSFCHs, where k is an integer greater than 1; arrange the selected k PSFCHs in ascending order based on the RSRP or the SINR; control the transceiver to perform an order determination that the k PSFCHs sorted in ascending order are hybrid automatic repeat request (HARQ) acknowledgments (ACK) or HARQ negative acknowledgments (NACK); and determine whether to retransmit a physical sidelink shared channel (PSSCH) based on the order determination. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other aspects, features, and advantages of certain embodiments of the present disclosure will become more apparent from the following description taken in conjunction with the accompanying drawings, in which:

[0020] Figure 1is a diagram for explaining the processes of unicast, multicast, and Physical SideLink Feedback Channel (PSFCH) transmission performed between terminals via a side link according to an embodiment;

[0021] Figure 2 is a diagram for explaining the process of transmitting signaling between a terminal and a base station and the process of transceiving channels between terminals according to an embodiment;

[0022] Figures 3 to 5 is a diagram for explaining the structure of the time - frequency range of a side link applied to a New Radio (NR) communication system according to an embodiment;

[0023] Figure 6 is a block diagram of a Radio Frequency (RF) transceiver component included in a terminal or a base station according to an embodiment;

[0024] Figure 7 is according to an embodiment Figure 6 a simplified block diagram of the RF transceiver component;

[0025] Figure 8 is a flowchart of the process of transmitting signaling between a terminal and a base station according to an embodiment;

[0026] Figure 9 is a flowchart of a method for determining the PSFCH of a terminal according to an embodiment;

[0027] Figure 10 is according to an embodiment Figure 9 a detailed flowchart of operations S1200 and S1300;

[0028] Figure 11 is a flowchart of a method for determining the PSFCH of a terminal according to an embodiment;

[0029] Figure 12 is according to an embodiment Figure 11 a detailed flowchart of operation S2000; and

[0030] Figure 13 is a diagram of a wireless communication device according to an embodiment. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings.

[0032] Various example embodiments will now be described more fully with reference to the accompanying drawings, which show some example embodiments. However, the embodiments may be embodied in different forms and should not be construed as limited to the embodiments set forth herein. The embodiments may be interchanged with each other. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope to those skilled in the art. Even when the content described in a particular embodiment is not described in other embodiments, the content may be understood to be relevant to other embodiments, unless otherwise stated or the content is contradictory to a particular embodiment in other embodiments. Throughout the specification, the same reference numerals generally denote the same elements.

[0033] The terms used herein are for the purpose of describing particular embodiments only and are not intended to limit the scope of other embodiments. Unless otherwise clearly specified in the context, the singular forms of expressions may include the plural forms. It will be further understood that when used herein, the terms "comprises," "comprising," "includes," and / or "having" specify the presence of the stated features, items, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, items, steps, operations, elements, components, and / or groups thereof.

[0034] Unless otherwise defined, all terms (including technical and scientific terms) used herein will be interpreted as being terms customary in the field to which this disclosure pertains. It will be further understood that terms of common usage should also be interpreted as being terms customary in the relevant field, rather than having an idealized or overly formal meaning, unless clearly defined herein.

[0035] In addition, the embodiments will be described in detail by focusing on the New Radio (NR) system and the Long Term Evolution (LTE) / Long Term Evolution-Advanced (LTE-A) system. However, in the judgment of those skilled in the art, the embodiments can be applied not only to other communication systems with a similar technical background, but also to other communication systems using licensed and unlicensed frequency bands with minor modifications within the scope of this disclosure.

[0036] Before the following detailed description, definitions of several words and phrases used throughout this specification will be described. The expression "coupled (combined / connected) to" and its derivatives can refer to any direct or indirect communication between at least two components, regardless of whether the at least two components are in physical contact with each other. The terms "send", "receive", and "communicate" and their derivatives can include direct communication and indirect communication. The terms "comprise" and "include" and their derivatives can mean include but not be limited to. The term "or" can be an inclusive word meaning "and / or". The expression "associated with" and its derivatives can mean include..., included in..., interconnected with..., contain..., contained in..., connected to / connected with..., combined with / combined to..., communicate with..., cooperate with..., between..., placed in parallel with..., adjacent to..., bound by..., have..., characterized by..., have a relationship with... etc. The term "controller" refers to a device, system, or a part thereof that controls at least one operation. A controller can be implemented in hardware or in a combination of hardware with software and / or firmware. The functions associated with any particular controller can be centralized or distributed locally or remotely. When the expression "at least one" is before a list of items, any and all combinations of one or more of the listed items can be used, or perhaps only one of the listed items is required. For example, the statement "at least one of A, B, and C" can include any one of the following: A, B, C, both A and B, both A and C, both B and C, and the combination of A, B, and C.

[0037] The various functions described below can be implemented or supported by one or more computer programs, each of which can consist of computer-readable program code and be executed on a computer-readable medium. As used herein, the terms "application" and "program" refer to one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, associated data, or portions thereof that are suitable for implementing appropriate computer-readable program code. The term "computer-readable program code" includes all types of computer code, including source code, object code, and executable code. The term "computer-readable medium" includes all types of media, such as read-only memory (ROM), random access memory (RAM), hard disk drive (HDD), compact disc (CD), digital video disc (DVD), or any other type of memory accessible by a computer. A "non-transitory" computer-readable medium does not include wired, wireless, optical, or other communication links that transmit transitory electrical signals or other signals. Non-transitory computer-readable media include media in which data can be permanently stored and media in which data can be stored and later overwritten, such as a rewritable optical disc or an erasable memory device.

[0038] In the various embodiments described below, a hardware access method will be used as an example for illustration. However, the various embodiments include techniques using both hardware and software, and thus, the various embodiments do not exclude software-based access methods.

[0039] In the following description, for the sake of brevity, by way of example, terms referring to control information, terms referring to reference entries, terms referring to network entities, terms referring to messages, and terms referring to components of a device will be provided. Accordingly, the embodiments are not limited to the terms described below, and other terms having equivalent technical meanings may be used alternatively.

[0040] Figure 1 is a diagram for explaining the unicast, multicast, and physical sidelink feedback channel (PSFCH) transmission processes performed between terminals via a sidelink according to an exemplary embodiment.

[0041] Figure 1 Shows a plurality of terminals configured to perform vehicle-to-everything (V2X) communication according to an example, such as a first terminal 21, a second terminal 23, a third terminal 25, a fourth terminal 27, a fifth terminal 29, a sixth terminal 31, a seventh terminal 33, and an eighth terminal 35.

[0042] First, it can be seen that the communication scheme between the first terminal 21 and the second terminal 23 is one-to-one communication, that is, unicast communication via a sidelink.

[0043] Although Figure 1 shows an example of sending a signal from the first terminal 21 to the second terminal 23, the signal can be sent in the opposite direction. That is, the signal can be sent from the second terminal 23 to the first terminal 21.

[0044] In addition, the operation of exchanging signals between the first terminal 21 and the second terminal 23 via unicast may include performing scrambling processing, control information mapping processing, data transmission processing, and unique identifier (ID) value verification processing by using resources or values known between the first terminal 21 and the second terminal 23. Moreover, the first terminal 21 and the second terminal 23 may be mobile terminals, such as vehicles.

[0045] Thereafter, it can be seen that the communication scheme between the third terminal to the fifth terminals 25, 27, and 29 is multicast communication, where the third terminal 25 sends common data to other terminals in the group via a sidelink, such as the fourth terminal 27 and the fifth terminal 29.

[0046] During multicast communication, other terminals not included in the group (such as the second terminal 23 and the seventh terminal 33) may not receive the signals for multicast sent by the third terminal 25.

[0047] As a reference, the terminal configured to transmit a signal for multicast may not be the third terminal 25, but another terminal in the group, for example, the fourth terminal 27 or the fifth terminal 29. Additionally, the allocation of resources for transmitting the signal may be determined by the base station or the terminal serving as the group leader in the group, or the allocation of resources for transmitting the signal may be selected by the terminal configured to transmit the signal. Additionally, the third to fifth terminals 25, 27, and 29 may be mobile terminals such as vehicles.

[0048] Finally, the communication between the sixth to eighth terminals 31, 33, and 35 will now be examined. The communication scheme may include communication in which the seventh terminal 33 and the eighth terminal 35 receive common data from the sixth terminal 31 in a multicast communication manner, and send feedback of information related to the success or failure of the reception of the common data to the sixth terminal 31. Although not shown, the feedback of information related to the success or failure of the reception of data may also be transmitted between terminals in unicast communication (e.g., the first terminal 21 and the second terminal 23).

[0049] As a reference, the information related to the success or failure of the reception of data may be hybrid automatic repeat request (HARQ)-acknowledgment / negative acknowledgment (ACK / NACK) information, which may be included in the PSFCH. Additionally, the sixth to eighth terminals 31, 33, and 35 may be mobile terminals such as vehicles.

[0050] As described above, various communication schemes may be applied between multiple terminals (e.g., the first to eighth terminals 21, 23, 25, 27, 29, 31, 33, and 35) configured to perform V2X communication according to the exemplary embodiments. Hereinafter, it will be described based on the V2X communication scheme Figure 2 .

[0051] Figure 2 is a diagram for explaining the process of transmitting signaling between a terminal and a base station and the process of transmitting and receiving channels between terminals according to an exemplary embodiment.

[0052] Referring to Figure 2 , the wireless communication system 1000 according to an exemplary embodiment may include a base station 51 and multiple terminals, for example, the terminal 53 and the terminal 55.

[0053] As a reference, although for simplicity, Figure 2 an example is shown in which the wireless communication system 1000 includes only two terminals 53 and 55 and one base station 51, the present disclosure is not limited thereto. That is, the wireless communication system 1000 may include more or fewer terminals and base stations.

[0054] Additionally, Figure 2Each of the terminals 53 and 55 shown in the figure can be capable of V2X communication. For example, referring to Figure 1 the unicast, multicast, and PSFCH transmissions described. Thus, although Figure 2 a unicast communication between two terminals 53 and 55 is shown in the figure, it Figure 2 can be interpreted as an illustration of a multicast communication between some terminals in a group.

[0055] The wireless communication system 1000 can be referred to as a radio access technology (RAT). For example, the wireless communication system 1000 can be a wireless communication system using a cellular network, such as, for example, an NR communication system, an LTE communication system, an advanced LTE (LTE-A) communication system, a code division multiple access (CDMA) communication system, and a global system for mobile communications (GSM). In an embodiment, the wireless communication system 1000 can be a wireless local area network (WLAN) communication system or any other wireless communication system.

[0056] The wireless communication network used in the wireless communication system 1000 can share available network resources and support the communication of multiple wireless communication devices included in the terminals 53 and 55.

[0057] For example, in the wireless communication network, various multiple access methods such as the following can be used to transmit information, such as, for example, CDMA, frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal FDMA (OFDMA), single carrier FDMA (SC-FDMA), OFDM-FDMA, OFDM-TDMA, and OFDM-CDMA.

[0058] In an embodiment, the wireless communication system 1000 can be an NR communication system. However, the example embodiments are not limited thereto and can also be applied to previous-generation and next-generation wireless communication systems.

[0059] In addition, the base station 51 can refer to a fixed station configured to communicate with the terminals 53 and 55 and / or another base station. The base station 51 can communicate with the terminals 53 and 55 and / or another base station and can exchange data and control information with the terminals 53 and 55 and / or another base station.

[0060] For example, the base station 51 can be referred to as a Node B, an evolved Node B (eNB), a next-generation Node B (gNB), a sector, a site, a base transceiver system (BTS), an access point (AP), a relay node, a remote radio head (RRH), or a radio unit (RU).

[0061] In this embodiment, the base station 51 can be interpreted as a base station controller (BSC) of CDMA, a Node B of Wideband CDMA (WCDMA), an eNB of LTE, a gNB of NR, or a partial area or function covered by a sector (site). The terminals 53 and 55 can be fixed devices as user equipment or mobile devices as vehicles, and can refer to any device capable of communicating with the base station 51, sending data and / or control information to the base station 51, and receiving data and / or control information from the base station 51.

[0062] For example, the terminals 53 and 55 can be referred to as a wireless station (STA), a mobile station (MS), a mobile terminal (MT), a user terminal (UT), a user equipment (UE), a subscriber station (SS), a wireless device, a handheld device, or a vehicle.

[0063] In addition, the base station 51 can be connected to the terminals 53 and 55 through a wireless channel, and can provide various communication services to the terminals 53 and 55 through the connected wireless channel. Moreover, all user services of the base station 51 can be served through a shared channel. Additionally, the base station 51 can schedule the terminals 53 and 55 by collecting status information such as PSFCH capabilities, buffer status, available transmission power status, and channel status of the terminals 53 and 55.

[0064] In addition, the wireless communication system 1000 can support beamforming technology using an orthogonal frequency division multiplexing (OFDM) scheme. Additionally, the wireless communication system 1000 can support an adaptive modulation and coding (AMC) scheme that determines a modulation scheme and a channel coding rate based on the channel status of the terminals 53 and 55.

[0065] As a reference, the wireless communication system 1000 can use a wideband that includes not only a frequency band less than 6 GHz but also a frequency band of 6 GHz or greater to transmit and receive signals.

[0066] For example, the wireless communication system 1000 can increase the data transmission rate by using a millimeter wave band such as the 28 GHz band or the 60 GHz band.

[0067] In the millimeter wave band, the signal attenuation per unit distance may be relatively large. Therefore, the wireless communication system 1000 can support transceiver operations based on directional beams to ensure coverage. In addition, the wireless communication system 1000 can perform a beam scanning operation based on directional beams to enable transceiver operations.

[0068] Here, the beam scanning operation may instruct the terminals 53 and 55 and the base station 51 to sequentially or randomly scan directional beams with a predetermined pattern to determine a transmit beam and a receive beam whose orientation directions are aligned with each other. That is, a pattern of a transmit beam and a receive beam whose orientation directions are aligned with each other may be determined as a pair of beam patterns. Moreover, the beam pattern may refer to the shape of the beam, which is determined based on the width of the beam and the orientation direction of the beam.

[0069] Since the terminals 53 and 55 and the base station 51 of the wireless communication system 1000 may be configured and operated as described above, the communication between the terminal 53 and the terminal 55 or the communication between the terminal 53 and 55 and the base station 51 will now be described in further detail.

[0070] The terminals 53 and 55 may send signals SIG1, SIG2, SIG4, and SIG4 to the base station 51 via the uplink or downlink and receive signals SIG1, SIG2, SIG4, and SIG4 from the base station 51, and access the network of the wireless communication system 1000. The link between the terminals 53 and 55 and the base station 51, such as a data transceiver interface, may be referred to as a Uu link. In addition, in order to exchange various setting information required for signal transceiver operations between the terminals 53 and 55 and the base station 51, a radio resource control (RRC) connection may be established between the terminal 53 or 55 and the base station 51. The RRC connection may be referred to as Uu-RRC.

[0071] Specifically, for example, the terminals 53 and 55 may send signals SIG2 and SIG4 for the maximum number of Physical Shared Feedback Channel (PSFCH) that can be transceived during one transmission time interval (TTI) (e.g., a time slot) to the base station 51. In an embodiment, the maximum number of PSFCH that can be transceived during one TTI may be referred to as the highest PSFCH transceiver capability or the maximum PSFCH transceiver capability. Additionally, information regarding the maximum PSFCH transceiver capability may correspond to RRC information, which may be one of the user equipment (UE) capability information elements. Therefore, due to RRC signaling, the terminals 53 and 55 may send signals SIG2 and SIG4 for the maximum PSFCH transceiver capability to the base station 51. Thus, information regarding the maximum PSFCH transceiver capability may be included in the Physical Uplink Shared Channel (PUSCH). In addition to the PUSCH, information regarding the maximum PSFCH transceiver capability may also be included in the Physical Uplink Control Channel (PUCCH) or the Physical Random Access Channel (PRACH), but the exemplary embodiment relates to an example where the information is included in the PUSCH.

[0072] For reference, in this embodiment, the content disclosed in Table 1 can be re-introduced and defined in combination with the maximum PSFCH transceiver capabilities of the terminal. Accordingly, terminal 53 and terminal 55 can signal the maximum PSFCH transceiver capabilities to base station 51 based on the items described in Table 1.

[0073] Table 1

[0074]

[0075] For example, "UE capability signaling" in item (1) of Table 1 can be expressed as shown in Table 2 below.

[0076] Table 2

[0077]

[0078] For example, "UE capability signaling" in item (2) of Table 1 can be expressed as shown in Table 3 below.

[0079] Table 3

[0080]

[0081] In addition, the content disclosed in Table 1 can be arranged as shown in Table 4-1 and Table 4-2 below.

[0082] Table 4-1

[0083]

[0084] Table 4-2

[0085]

[0086] For reference, Table 4-1 and Table 4-2 are tables obtained by dividing a continuous table due to limited space.

[0087] As described above, in the exemplary embodiment, terminal 53 or terminal 55 can signal the maximum PSFCH transceiver capabilities to base station 51, examples of which will be described in further detail with reference to Figure 8 Furthermore, base station 51 can perform RRC signaling on terminal 53 and terminal 55 based on the signaling from terminal 53 and terminal 55, such as signal SIG1 and signal SIG3, and perform scheduling operations for transmitting and receiving signals (e.g., PSSCH, PSCCH, and PSFCH) between terminal 53 and terminal 55, or perform multicast-related setup operations, such as selecting a group leader in the group and setting the size of the area for multicast.

[0088] As a reference, the terminals 53 and 55 can receive scheduling information for sidelink communication based on RRC signaling (e.g., signal SIG1 and signal SIG3) from the base station 51 or information (e.g., downlink control information (DCI)) of the physical downlink control channel (PDCCH).

[0089] In addition, the terminals 53 and 55 can send and receive signals to and from each other via the sidelink, such as channels CH1, CH2, and CH3. The sidelink between the terminals 53 and 55, such as a data transceiver interface, can be referred to as a PC5 link. In addition, in order to exchange various setting information required for sending and receiving signals between the terminals 53 and 55, an RRC connection can be established between the terminals 53 and 55. The RRC connection can be referred to as PC5-RRC.

[0090] Here, the channels transmitted and received via the sidelink can include, for example, a sidelink control channel (e.g., physical sidelink control channel (PSCCH)), a sidelink shared channel or data channel (e.g., physical sidelink shared channel (PSSCH)), a sidelink broadcast channel (e.g., physical sidelink broadcast channel (PSBCH) broadcast using a synchronization signal), and a feedback transmission channel (e.g., physical sidelink feedback channel (PSFCH)).

[0091] In an embodiment, the terminal 53 configured to perform a data transmission operation in the sidelink can be referred to as a transmitting terminal, and the terminal 55 configured to perform a data reception operation in the sidelink can be referred to as a receiving terminal. Both the transmitting terminal and the receiving terminal can perform a data transmission operation and a data reception operation in the sidelink, respectively.

[0092] The transmitting terminal 53 can generate sidelink scheduling information, such as sidelink control information (SCI), based on the scheduling information provided by the base station 51. In addition, the transmitting terminal 53 can send the PSCCH CHl including the generated sidelink scheduling information to the receiving terminal 55.

[0093] Here, the sidelink scheduling information can be sent to the receiving terminal 55 as a single SCI, or the sidelink scheduling information can be divided into two parts of SCI and sent to the receiving terminal 55. As a reference, the method of dividing the sidelink scheduling information into two parts of SCI and sending it to the receiving terminal 55 can be referred to as 2-level SCI or 2-level PSCCH.

[0094] The transmitting terminal 53 may transmit the PSSCH CH2, which is a data channel, to the receiving terminal 55 based on the sidelink scheduling information. Additionally, the receiving terminal 55 may send feedback to the transmitting terminal 53 on the PSFCH CH3, and the feedback includes information related to the success or failure of receiving the PSSCH CH2 transmitted by the transmitting terminal 53, such as HARQ-ACK / NACK. Therefore, the transmitting terminal 53 may determine whether the PSFCH CH3 received from the receiving terminal 55 includes a HARQ ACK or NACK, and determine whether to retransmit the PSSCH CH2 based on the determination result.

[0095] As described above, various signals or channels may be transmitted and received between the terminal 53 and the terminal 55 and the base station 51, as will be described in further detail below.

[0096] The wireless communication system 1000 according to the exemplary embodiment has the features and configurations as described above. Therefore, now, with reference to Figures 3 to 5 The structure of the time-frequency range applied to the sidelink of the NR communication system according to the exemplary embodiment will be described.

[0097] For reference, Figures 3 to 5 The structure of the shown time-frequency range may be an example of the time-frequency range applicable to this embodiment, and thus, the present disclosure is not limited thereto. However, for simplicity, the structure of the time-frequency range shown will be described as an example. Figures 3 to 5 The structure of the shown time-frequency range will be described as an example.

[0098] First, with reference to Figure 3 , the horizontal line represents the time region, and the vertical line represents the frequency range. The minimum transmission unit in the time domain may be an OFDM symbol, and N symb OFDM symbols may form a time slot. The length of a subframe may be 1.0 ms, and the length of a radio frame may be 10 ms. The minimum transmission unit in the frequency range may be a subcarrier, and the system transmission bandwidth may include the total number of N BW subcarriers.

[0099] In the time-frequency range, the basic unit of a resource may be a resource element (RE), which may be represented by an OFDM symbol index and a subcarrier index. A resource block (RB) or a physical resource block (PRB) may be defined by N symb consecutive OFDM symbols in the time domain and N RB consecutive subcarriers in the frequency domain. Therefore, one RB may include N symb × N RB RES.

[0100] For reference, the minimum transmission unit of data may generally be in RB units. In the NR communication system, generally, N symbcan be at least one, N RB can be equal to 12, and N BW and N RB can be proportional to the system transmission bandwidth. Moreover, the data rate can increase proportionally to the number of RBs scheduled for the terminal.

[0101] In addition, the channel bandwidth can indicate the RF bandwidth corresponding to the system transmission bandwidth. For example, in an NR communication system with a channel bandwidth of 100 MHz at a subcarrier width of 30 kHz, the transmission bandwidth can include 273 RBs.

[0102] Based on the above description, referring to Figure 4 and Figure 5 , subchannels and resource pools defined to improve the resource utilization efficiency in Release-16 (Rel-16) NR V2X communication are shown. For reference, Figure 4 the basic frame structure of NR V2X communication and the level 2 PSCCH is shown, such as the structure in the time-frequency domain. In addition, Figure 5 the resource pool is shown in

[0103] Specifically, in NR V2X communication, one time slot can include at least one resource pool, and each resource pool can include multiple subchannels. Here, the size of the subchannel can be any one of, for example, 10 RBs, 15 RBs, 20 RBs, 25 RBs, 50 RBs, 75 RBs, and 100 RBs. However, depending on the situation, the size of the subchannel can be any one of 4 RBs, 5 RBs, and 6 RBs. As an example, Figure 4 an example including subchannel #1 and subchannel #2 is shown, and each of subchannel #1 and subchannel #2 includes 15 RBs, shown as RB#0 of subchannel #1 to RB#14 of subchannel #1, and RB#0 of subchannel #2 to RB#14 of subchannel #2.

[0104] In addition, the 0th symbol (symbol 0) of the time slot can be a symbol for automatic gain control (AGC) training.

[0105] Furthermore, the PSFCH for determining whether the PSSCH is received normally can be allocated and transmitted in the 12th symbol (symbol 12) of the time slot. The transmission timing can be in two or three time slots after the time slot in which the PSSCH is transmitted. For example, when the PSSCH is transmitted in time slot A, the PSFCH corresponding to the PSSCH can be feedback-transmitted in time slot A + 2 or time slot A + 3.

[0106] For reference, the PSFCH may include 1 PRB (or 1 RB) and is transmitted for each subchannel. Additionally, the transmission and reception period of each PSFCH may be set, and the minimum value of the transmission and reception period may be defined as 1, for example, 1 time slot unit. Since multiple PSFCHs may use the same resources, up to six cyclic shifts may be applied to different PSFCHs transmitted to the same RB. Therefore, up to ((273 PRBs) / (4 PRBs / subchannel) * 6 cyclic shift pairs / subchannel) ≈ 410 PSFCHs may be transmitted during each time slot.

[0107] The AGC (AGC(PSFCH)) for receiving the PSFCH may be allocated in the symbol immediately preceding the PSFCH (e.g., symbol 11). Since the transmission targets of the 0th symbol to the 9th symbol (symbol 0 to symbol 9) (e.g., the transmitting terminal) are different from those of the 11th symbol and the 12th symbol (symbol 11 and symbol 12) (e.g., the receiving terminal), a separate AGC for the PSFCH may be required.

[0108] Additionally, guard symbols may be allocated to the 10th symbol and the 13th symbol (symbol 10 and symbol 13) to ensure the guard time for timing advance. Since the transmission targets of the 0th symbol to the 9th symbol (symbol 0 to symbol 9) are different from those of the 11th symbol and the 12th symbol (symbol 11 and 12), the receiver may misalign the symbol timing, and thus guard symbols may be required.

[0109] The demodulation reference signal (DMRS), PSCCH, and PSSCH may be allocated to the 1st symbol to the 9th symbol (symbol 1 to symbol 9) other than the above channels and symbols. Additionally, the PSFCH, AGC, and guard symbols may be allocated to the 1st symbol to the 9th symbol (symbol 1 to symbol 9). However, for simplicity, the exemplary embodiment relates to an example in which the PSFCH, AGC, and guard symbols are allocated to the 10th symbol to the 13th symbol.

[0110] For reference, in NR V2X communication, since the PSCCH is transmitted in two levels, the first PSCCH may initially be allocated to the PSCCH scheduling range, and the second PSCCH may be allocated to the PSSCH range.

[0111] More specifically, the first PSCCH may originate from the lowest RB of a subchannel (e.g., RB#0 of subchannel #0) and include the first SCI. Additionally, the first SCI may include allocation information for the PSSCH (e.g., frequency-domain resource allocation (FDRA) and time-domain resource allocation (TDRA)) and allocation information for the second PSCCH. The second PSCCH may include the second SCI and is first allocated to the lowest RE other than the REs of the DMRS in the first DMRS symbol (e.g., the DMRS of symbol 0), such as SC#1, where SC refers to a subcarrier. Additionally, the second SCI may include information required to decode the PSSCH.

[0112] As described above, according to this embodiment, the time-frequency range applicable to the sidelink of an NR communication system can be configured. Hereinafter, reference will be made to Figure 6 and Figure 7 to describe the configuration of a radio frequency (RF) transceiver of a terminal or a base station according to an exemplary embodiment.

[0113] Figure 6 is a block diagram of an RF transceiver component included in a terminal or a base station according to an exemplary embodiment. Figure 7 is according to an embodiment of Figure 6 a simplified block diagram of an RF transceiver component.

[0114] As a reference, Figure 6 and Figure 7 the RF transceiver components of Figure 2 may be included in the Figure 6 and Figure 7 terminal 53 or terminal 55 or base station 51 of

[0115] Hereinafter, for simplicity, a description will be given of Figure 6 and Figure 7 an example in which the RF transceiver component shown in Figure 2 is included in the Figure 6 terminal 53. Additionally, the baseband circuit 120 of

[0116] will be described centering on the components in the receive path. Figure 6 First, referring to

[0117] The antenna 90 can be connected to the FEM 105 and can transmit the signal provided by the FEM 105 to another wireless communication device, such as a terminal or a base station, or can provide the signal received from another wireless communication device to the FEM 105. Moreover, the FEM 105 can be connected to the antenna 90 and can separate the transmission frequency from the reception frequency. That is, the FEM 105 can separate the signal provided by the RFIC 110 for each frequency band and can provide the separated signal to the corresponding antenna 90. In addition, the FEM 105 can provide the signal provided by the antenna 90 to the RFIC 110.

[0118] As described above, the antenna 90 can transmit the signal with separated frequencies to the outside, for example, to the outside of a terminal such as the terminal 53, or can provide the signal received from the outside to the FEM 105.

[0119] As a reference, the antenna 90 can include, for example, an array antenna, but is not limited thereto. Moreover, the antenna 90 can be provided singly or in multiple numbers. Therefore, in some embodiments, the terminal 53 can use multiple antennas to support phased arrays and multiple-input multiple-output (MIMO). However, for the sake of simplicity, Figure 6 only one antenna 90 is shown.

[0120] The FEM 105 can include an antenna tuner. The antenna tuner can be connected to the antenna 90 and adjust the impedance of the antenna 90.

[0121] The RFIC 110 can perform upconversion on the baseband signal received from the baseband circuit 120 and generate an RF signal. Moreover, the RFIC 110 can perform downconversion on the RF signal received from the FEM 105 and generate a baseband signal.

[0122] Specifically, the RFIC 110 can include a transmit circuit 112 for upconversion operations, a receive circuit 114 for downconversion operations, and a local oscillator 116.

[0123] As a reference, the transmit circuit 112 can include a first analog baseband filter, a first mixer, and a power amplifier. Moreover, the receive circuit 114 can include a second analog baseband filter, a second mixer, and a low-noise amplifier.

[0124] Here, the first analog baseband filter can filter the baseband signal received from the baseband circuit 120 and provide the filtered baseband signal to the first mixer. Moreover, the first mixer can perform up-conversion to convert the frequency of the baseband signal from the baseband to the high band according to the frequency of the signal provided by the local oscillator 116. Due to the up-conversion, the baseband signal can be provided to the power amplifier as an RF signal, and the power amplifier can amplify the power of the RF signal and provide the RF signal with amplified power to the FEM 105.

[0125] The low-noise amplifier can amplify the RF signal provided by the FEM 105 and provide the amplified RF signal to the second mixer. The second mixer can perform down-conversion to convert the frequency of the RF signal from the high band to the baseband according to the frequency of the signal provided by the local oscillator 116. Due to the down-conversion, the RF signal can be provided to the second analog baseband filter as a baseband signal, and the second analog baseband filter can filter the baseband signal and provide the filtered baseband signal to the baseband circuit 120.

[0126] In addition, the baseband circuit 120 can receive the baseband signal from the RFIC 110 and process the baseband signal, or generate the baseband signal and provide the baseband signal to the RFIC 110.

[0127] In addition, the baseband circuit 120 can include a controller 122, a memory 124, and a signal processing unit 125.

[0128] Specifically, the controller 122 can not only control the overall operation of the baseband circuit 120, but also control the overall operation of the RFIC 110. Moreover, the controller 122 can write data to the memory 124 or read data from the memory 124. To this end, the controller 122 can include at least one processor, at least one microprocessor, or at least one microcontroller, or can be a part of a processor. More specifically, the controller 122 can include, for example, a central processing unit (CPU) and a digital signal processor (DSP).

[0129] The memory 124 can store basic programs, application programs, and data for the operation of the terminal 53, such as setting information. For example, the memory 124 can store instructions and / or data associated with the controller 122, the signal processing unit 125, or the RFIC 110.

[0130] In addition, the memory 124 may include various storage media. That is, the memory 124 may include volatile memory, non-volatile memory, or a combination of volatile memory and non-volatile memory. For example, the memory 124 may include random access memory (RAM) (e.g., dynamic RAM (DRAM), phase change RAM (PRAM), magnetic RAM (MRAM), and static RAM (SRAM)), as well as flash memory (e.g., NAND flash memory, NOR flash memory, and OneNAND flash memory).

[0131] In addition, the memory 124 may store various processor-executable instructions. The processor-executable instructions may be executed by the controller 122.

[0132] The signal processing unit 125 may process the baseband signal received from the RFIC 110.

[0133] Specifically, the signal processing unit 125 may include a demodulator 126, a receiver filter and cell searcher (RxFilter&cell searcher) 128, and other components 130.

[0134] First, the demodulator 126 may include a channel estimator, a data deallocation unit, an interference whitener, a symbol detector, a channel state information (CSI) generator, a mobility measurement unit, an automatic gain control unit, an automatic frequency control unit, a symbol timing recovery unit, a delay spread estimation unit, and a time correlator, and perform the functions of each of the above components.

[0135] Here, the mobility measurement unit may be a unit configured to measure the signal quality of a serving cell and / or an adjacent cell to support mobility. The mobility measurement unit may measure the received signal strength indicator (RSSI), reference signal received power (RSRP), reference signal received quality (RSRQ), reference signal (RS)-signal to interference plus (&)-noise ratio (SINR) of the cell.

[0136] As a reference, although not shown, the demodulator 126 may include a plurality of sub-demodulators configured to independently or jointly perform the above operations on signals de-spread in a second generation (2G) communication system, a third generation (3G) communication system, a fourth generation (4G) communication system, and a fifth generation (5G) communication system, respectively, or signals in each frequency band.

[0137] Thereafter, the receiver filter and the cell searcher 128 may include a receiver filter (RxFilter), a cell searcher, a fast Fourier transform (FFT) unit, a time-division duplex automatic gain control (TD-AGC) unit, and a time-division duplex automatic frequency control (TD-AFC) unit.

[0138] Here, the receiver filter (RxFilter), which may also be referred to as the receiver (Rx) front end, may perform sampling, interference cancellation, and amplification on the baseband signal received from the RFIC 110. Moreover, the cell detector may include a primary synchronization signal (PSS) detector and a secondary synchronization signal (SSS) detector, and may measure the amplitude and quality of signals from adjacent cells.

[0139] In addition, the other components 130 may include a symbol processor, a channel decoder, and an uplink processor.

[0140] Here, the symbol processor may perform channel deinterleaving, demultiplexing, and rate matching to decode the demodulated signals of each channel. Moreover, the channel decoder may decode the demodulated signals in units of code blocks.

[0141] For reference, the symbol processor and the channel decoder may include a hybrid automatic repeat request (HARQ) processing unit, a turbo decoder, a cyclic redundancy check (CRC) checker, a Viterbi decoder, and a turbo encoder.

[0142] The uplink processor, which is a processor configured to generate a transmission baseband signal, may include a signal generator, a signal distributor, an inverse fast Fourier transform (IFFT) unit, a discrete Fourier transform (DFT) unit, and a transmitter (Tx) front end.

[0143] Here, the signal generator may generate PUSCH, PUCCH, and PRACH. Additionally, the Tx front end may perform operations such as interference cancellation and digital mixing on the transmission baseband signal.

[0144] For reference, the other components 130 may also include a sidelink processor. The sidelink processor may generate a physical sidelink shared channel (PSSCH), a physical sidelink control channel (PSCCH), and a physical sidelink feedback channel (PSFCH). In another case, the sidelink processor may not be provided separately, but may be integrated with the uplink processor into one processor. However, for the sake of simplicity, the exemplary embodiments relate to an example in which the sidelink processor is provided separately from the uplink processor.

[0145] The signal processing unit 125 may have the above configuration and characteristics. However, the respective configurations or functions of the demodulator 126, receiver filter, and cell searcher 128, and other components 130 in the signal processing unit 125 may be changed. For example, the channel estimator in the demodulator 126 may be included in the receiver filter and cell searcher 128 or other components 130, and the FFT unit in the receiver filter and cell searcher 128 may be included in the demodulator 126 or other components 130. Moreover, the channel decoder in other components 130 may be included in the demodulator 126 or the receiver filter and cell searcher 128. However, for the sake of brevity, the exemplary embodiments relate to examples in which the respective configurations or functions of the demodulator 126, receiver filter, and cell searcher 128, and other components 130 in the signal processing unit 125 are implemented as described above.

[0146] As described above, Figure 6 The case where the baseband circuit 120 includes the controller 122, the memory 124, and the signal processing unit 125 is shown.

[0147] However, at least two of the controller 122, the memory 124, and the signal processing unit 125 may be integrated into one component in the baseband circuit 120. In addition, the baseband circuit 120 may further include other components in addition to the above components, or may not include some components. In addition, the signal processing unit 125 may further include other components in addition to the above components, or may not include some components.

[0148] However, for the sake of brevity, the exemplary embodiments relate to examples in which the baseband circuit 120 includes the above components.

[0149] In addition, in some embodiments, the controller 122, the memory 124, and the signal processing unit 125 may be included in one device. In other embodiments, the controller 122, the memory 124, and the signal processing unit 125 may be distributed, for example, in a distributed architecture and included in respectively different devices.

[0150] With the above configuration Figure 6 the RF transceiver component may be included in, for example, Figure 2 one or more of the terminal 53 or terminal 55 or base station 51.

[0151] The RFIC 110 and the baseband circuit 120 may include components well known to those skilled in the art as Figure 6 shown. In addition, these components may be executed in a known manner by using hardware, firmware, software logic, or a combination thereof.

[0152] However, Figure 6Only an example of the RF transceiver component is shown, and the embodiments are not limited thereto. That is, various changes can be made, such as adding or deleting components, in Figure 6 For example, adding or deleting components.

[0153] Figure 7 An example is shown where the configuration of the RF transceiver component of Figure 6 is partially changed (e.g., simplified).

[0154] Specifically, the terminal 53 may include a processor 150, a transceiver 160, a memory 170, and an antenna 180.

[0155] The processor 150 may control the overall operation of the transceiver 160 and may write data to or read data from the memory 170. That is, the processor 150 may be a component, for example, including the functions of the controller 122 of Figure 6

[0156] The transceiver 160 may transmit and receive wireless signals and be controlled by the processor 150. That is, the transceiver 160 may be a component, for example, including the functions of the FEM 105, the RFIC 110, and the signal processing unit 125 of Figure 6

[0157] The memory 170 may include basic programs, application programs, and data for the operation of the terminal 53, such as setting information. Thus, the memory 170 may store instructions and / or data associated with the processor 150 and the transceiver 160. That is, the memory 170 may be a component, for example, including the functions of the storage 124 of Figure 6

[0158] The antenna 180 may be connected to the transceiver 160 and may transmit the signal provided by the transceiver 160 to another wireless communication device, such as a terminal or a base station, or may provide the signal received from another wireless communication device to the transceiver 160. That is, the antenna 180 may be a component, for example, including the functions of the antenna 90 of Figure 6

[0159] Because in the exemplary embodiments the terminal 53 or the terminal 55 or the base station 51 has the above characteristics and configurations, now an example of the process of enabling V2X communication by signaling between the terminal 53 or the terminal 55 and the base station 51 will be described in detail with reference to Figure 8

[0160] Figure 8 is a flowchart of the signaling process executed between the terminal 53 or the terminal 55 and the base station 51 according to an embodiment in Figure 2

[0161] For reference, with reference toFigure 2 and Figure 7 describe Figure 8 .

[0162] Referring Figure 8 , in order to enable effective PSFCH transceiver operations in V2X communication, signaling can be mutually sent between, for example, terminal 53 which can be a transmitting terminal and base station 51.

[0163] First, at operation S100, in order to enable effective PSFCH transceiver operations, terminal 53 can signal to base station 51 the maximum number of PSFCHs that can be received during one TTI. In an embodiment, the maximum number of PSFCHs that can be received during one TTI can be referred to as the highest PSFCH reception capacity F or the maximum PSFCH reception capacity F.

[0164] Specifically, processor 150 can control transceiver 160 to signal to base station 51 the maximum PSFCH reception capacity F.

[0165] Here, a TTI can include time slots, and the maximum PSFCH reception capacity F can include the number of PSFCHs received in at least one of multicast and unicast. That is, the maximum PSFCH reception capacity F can include the total number of PSFCHs received in each of multicast and unicast, or can include only the number of PSFCHs received in multicast or unicast. Thus, the maximum PSFCH reception capacity F can be any one of, for example, 10, 20, 30, 40, 50, 100, 200, 300, and 410.

[0166] At operation S150, when base station 51 receives a signal regarding the maximum PSFCH reception capacity F from terminal 53, base station 51 can set the sidelink communication of terminal 53 to satisfy the following inequality: F ≥ L × M × N.

[0167] As a reference, F can refer to the maximum number of PSFCHs that can be received during one time slot, and L can refer to the number of PSSCHs transmitted in multicast during each time slot. Additionally, M can refer to the number of receiving terminals that serve as transmitting terminals in the same group (e.g., a group of terminals for multicast), and N can refer to the PSFCH reception period.

[0168] That is, in order to enable effective PSFCH transceiver operations, base station 51 can determine values L, M, and N associated with terminal 53 considering the highest PSFCH reception capacity F. In addition, base station 51 can also consider the following method in the multicast mode to satisfy the above inequality.

[0169] 1) When the inequality F < L × M × N related to the receiving terminals included in the group is satisfied, the base station 51 may determine that among the receiving terminals included in the same group as the transmitting terminal, the "NACK-based HARQ" that receives only one common PSFCH from each receiving terminal corresponding to NACK is the HARQ scheme. In this case, the value of M may be 1.

[0170] 2) When the inequality F ≥ L × M × N related to the receiving terminals included in the group is satisfied, the base station 51 may determine the "ACK / NACK-based HARQ" in which the transmitting terminal receives the PSFCH from each of all the receiving terminals included in the same group as the transmitting terminal as the HARQ scheme.

[0171] 3) To satisfy the inequality F ≥ L × M × N, the base station 51 may determine the size of the area, which is the range of the area set by the base station 51 to enable multicast. For example, when the terminals included in the group have a high value of F, the base station 51 may set the area to a larger size; conversely, when the terminals included in the group have a low value of F, the base station 51 may set the area to a smaller size. As a reference, the number of terminals included in the group may be determined based on the size of the area.

[0172] 4) When determining the group leader configured to perform multicast among the terminals included in the group, the base station 51 may select a terminal having a value of F that satisfies the inequality F ≥ L × M × N as the group leader. When multiple terminals satisfy the above conditions, the base station 51 may select a terminal having the best channel state as the group leader.

[0173] In addition, at operation S200, in order to enable an effective PSFCH transceiver operation, the terminal 53 may signal to the base station 51 the maximum number of PSFCHs that can be transmitted during one TTI. In an embodiment, the maximum number of PSFCHs that can be transmitted during one TTI may be referred to as the highest PSFCH transmission capacity R or the maximum PSFCH transmission capacity R.

[0174] Specifically, the processor 150 may control the transceiver 160 to signal the maximum PSFCH transmission capacity R to the base station 51.

[0175] Here, the TTI may include time slots, and the maximum PSFCH transmission capacity R may include the number of PSFCHs transmitted in at least one of multicast and unicast. That is, the maximum PSFCH transmission capacity R may include the total number of PSFCHs transmitted in each of multicast and unicast, or may include only the number of PSFCHs transmitted in multicast or unicast. Therefore, the maximum PSFCH transmission capacity R may be any one of, for example, 1, 2, 3, 4, 5, 10, 20, 30, and 68.

[0176] As a reference, operation S200 may be performed before operation S100, or operations S100 and S200 may be performed simultaneously. In addition, the terminal 53 may perform only one of operations S100 and S200, and the base station 51 may perform only a specific operation S150 or operation S250, or only a part of operation S150 or operation S250 according to the operation performed by the terminal 53. However, for the sake of simplicity, the exemplary embodiment relates to an example in which operation S200 is performed after operation S100 and the terminal 53 performs both operations S100 and S200.

[0177] When the base station 51 receives signaling information about the maximum PSFCH transmission capacity R from the terminal 53, at operation S250, the base station 51 may set the sidelink communication of the terminal 53 to satisfy the following inequality: U + G ≥ R.

[0178] As a reference, U may refer to the number of PSSCHs received by unicast during one time slot, and G may refer to the number of PSSCHs received by multicast during one time slot. In addition, R may refer to the maximum number of PSFCHs that can be transmitted during one time slot.

[0179] That is, in order to enable efficient PSFCH transceiver operations, the base station 51 may determine the unicast and / or multicast to which the terminal 53 may belong by considering the maximum PSFCH transmission capacity R based on the inequality U + G ≥ R. In addition, in order to satisfy the above inequality, the base station 51 may prioritize unicast and multicast, and determine R receiving channels (for example, R receiving channels that can be received by unicast and multicast) as the receiving channels of the terminal 53 according to the order of higher priority.

[0180] As described above, due to the above process, at operation S300, the base station 51 may perform RRC signaling for the terminal 53 based on the signaling received from the terminal 53. Therefore, the base station 51 may perform a scheduling operation for the sidelink communication of the terminal 53 or perform a setting operation related to multicast, for example, selecting a group leader in the group and setting the size of the area for multicast.

[0181] As described above, signaling may be mutually transmitted between the terminal 53 and the base station 51 to enable effective PSFCH transceiver operations in V2X communication. Hereinafter, reference will be made to Figure 9 and Figure 10 to describe an example of a method for determining a PSFCH of a terminal in V2X communication according to an exemplary embodiment.

[0182] Figure 9 is a flowchart of a method for determining a PSFCH of a terminal according to an exemplary embodiment. Figure 10is according to an exemplary embodiment Figure 9 detailed flowchart of operations S1200 and S1300

[0183] For reference, with reference to Figure 2 and Figure 7 describe Figure 9 and Figure 10 .

[0184] Reference Figure 9 , first, at operation S1000, k PSFCHs can be selected from all PSFCHs received during one TTI (where k is an integer greater than 1), and the RSRP or SINR of the selected k PSFCHs can be measured.

[0185] Specifically, the processor 150 can select k PSFCHs from all PSFCHs based on a preset specific criterion or randomly. Moreover, the processor 150 can control the transceiver 160 to sequentially measure the RSRP or SINR of k PSFCHs among all PSFCHs received during one TTI (where k is an integer greater than 1).

[0186] For reference, after all k PSFCHs are selected, the processor 150 can control the transceiver 160 to sequentially measure the RSRP or SINR of the k PSFCHs. In an embodiment, whenever a PSFCH is selected, the processor 150 can control the transceiver 160 to immediately measure the RSRP or SINR of the selected PSFCH.

[0187] Here, k can be preset by the manufacturer or user of the terminal 53 based on at least one of the channel state of the terminal 53, the performance of the terminal 53, and the total number of PSFCHs. Moreover, for example, when the base station (e.g., Figure 8 the base station 51 in) sets the sidelink, the terminal 53 can be guided to set k to any one of the values within a specific range.

[0188] When sequentially measuring the RSRP or SINR of the selected k PSFCHs, at operation S1100, the k PSFCHs can be sorted in ascending order based on the measured RSRP or SINR.

[0189] Specifically, the processor 150 can sort the k PSFCHs in ascending order based on the RSRP or SINR of the k PSFCHs measured by the transceiver 160. When the ascending sorting of the k PSFCHs is completed, at operation S1200, it can be sequentially determined whether the k PSFCHs sorted in ascending order are HARQ ACK or HARQ NACK, and at operation S1300, it can be determined whether to retransmit the PSSCH based on the determination result.

[0190] Specifically, the processor 150 may control the transceiver 160 to sequentially determine whether the k PSFCHs sorted in ascending order are HARQ ACK or HARQ NACK. Moreover, the processor 150 may determine whether to retransmit the PSSCH based on the determination result.

[0191] For reference, the HARQ ACK / NACK determination operation may be performed by a channel decoder of the transceiver 160 (e.g., Figure 6 the channel decoder included in other components 130).

[0192] Figure 10 An example of operation S1200 and operation S1300 according to an embodiment is specifically shown.

[0193] Specifically, referring to Figure 10 , operation S1200 may start from operation S1210, which determines whether the m-th PSFCH (where 1 ≤ m (integer) ≤ k) among the sorted k PSFCHs is HARQ ACK or HARQ NACK.

[0194] Therefore, if it is determined at operation S1220 that the m-th PSFCH (where 1 ≤ m (integer) ≤ k) among the sorted k PSFCHs is HARQ ACK, it may be determined at operation S1320 whether m is less than k. Based on the determination result of operation S1320, the HARQ ACK / NACK determination operation may be performed on the (m + 1)-th PSFCH to the k-th PSFCH among the sorted k PSFCHs (return to operation S1210), or the HARQ ACK / NACK determination operation on the sorted k PSFCHs may end (proceed to operations S1330 to S1350).

[0195] For example, when m is less than k, for example, when there is at least one PSFCH among the sorted k PSFCHs for which the HARQ ACK / NACK determination operation has not been performed, the HARQ ACK / NACK determination operation may be sequentially performed on the (m + 1)-th PSFCH to the k-th PSFCH at operation S1210.

[0196] Otherwise, when m is equal to k, for example, when the HARQ ACK / NACK determination operation for the sorted k PSFCHs is completely performed, the HARQ ACK / NACK determination operation for the sorted k PSFCHs can end, and by proceeding to operation S1330 to operation S1350, it can be determined whether to continue the RSRP or SINR measurement operation for the next k PSFCHs according to whether there is at least one PSFCH among all PSFCHs for which the HARQ ACK / NACK determination operation has not been performed.

[0197] Specifically, at operation S1330, when there is at least one PSFCH among all PSFCHs for which the HARQ ACK / NACK determination operation has not been performed, the RSRP or SINR measurement operation for the next k PSFCHs can continue at operation S1340. In this case, the above operations S1100 to S1300 can be sequentially performed on the next k PSFCHs. Otherwise, at operation S1330, when there is no PSFCH among all PSFCHs for which the HARQ ACK / NACK determination operation has not been performed, at operation S1350, the HARQ ACK / NACK determination operation for all PSFCHs can end.

[0198] In addition, at operation S1220, when it is determined that the m-th (where 1 ≤ m (integer) ≤ k) PSFCH among the sorted k PSFCHs is a HARQ NACK, the HARQ ACK / NACK determination operation for the (m + 1)-th to k-th PSFCHs among the sorted k PSFCHs can be interrupted, and at operation S1310, it is determined to retransmit the PSSCH.

[0199] As a reference, if it is determined to retransmit the PSSCH, all PSSCHs can be retransmitted, such as all PSSCHs corresponding to all PSFCHs. In addition, the above operations S1210 to S1350 can be executed by the processor 150 and the transceiver 160.

[0200] Specifically, according to the exemplary embodiment, in the method for determining the PSFCH of the terminal 53, after completing the measurement of the RSRP or SINR of the selected k PSFCHs (refer to operation S1000), instead of selecting a new k PSFCHs again from the remaining PSFCHs, subsequent processing operations, such as ACK / NACK determination operations, can be performed on the k PSFCHs selected in operation S1000 before selecting a new k PSFCHs. Therefore, compared with the case of immediately determining whether all PSFCHs are ACK or NACK, the complexity of the ACK / NACK determination operation can be reduced, and the processing time and memory required for the ACK / NACK determination operation can be reduced. Additionally, since the PSFCHs with low RSRP or SINR among the selected k PSFCHs are first determined as ACK or NACK, NACK can be determined quickly.

[0201] As described above, the method for determining the PSFCH of the terminal according to the exemplary embodiment can be performed. Hereinafter, with reference to Figure 11 and Figure 12 an example of the method for determining the PSFCH of the terminal according to another exemplary embodiment will be described.

[0202] Figure 11 is a flowchart of the method for determining the PSFCH of the terminal according to the exemplary embodiment. Figure 12 is Figure 11 a detailed flowchart of operation S2000 of

[0203] As a reference, with reference to Figure 2 and Figure 7 will be described Figure 11 and Figure 12 .

[0204] Referring to Figure 11 , first, at operation S2000, the RSRP or SINR of all PSFCHs received during one TTI can be measured, and k PSFCHs that meet a preset criterion can be selected from the PSFCHs whose RSRP or SINR has been measured. Here, k can be an integer greater than 1.

[0205] Specifically, the processor 150 can control the transceiver 160 to sequentially measure the RSRP or SINR of all PSFCHs received during one TTI. When the number of PSFCHs that meet the preset criterion among the PSFCHs whose RSRP or SINR has been measured reaches k, the selection operation (e.g., operation S2000) can end.

[0206] Figure 12 Specifically shows an example of operation S2000.

[0207] Specifically, referring to Figure 12 , operation S2000 may start from operation S2010 of measuring the RSRP or SINR of the nth PSFCH, where n is a positive integer less than the total number of PSFCHs.

[0208] Therefore, at operation S2010, when measuring the RSRP or SINR of the nth PSFCH (where n is a positive integer less than the total number of PSFCHs), it may be determined at operation S2020 whether the nth PSFCH meets a preset criterion.

[0209] If it is determined that the nth PSFCH meets the preset criterion, then at operation S2030, the cumulative count of the PSFCHs that meet the preset criterion may be incremented by 1. At operation S2040, when the incremented cumulative count (e.g., the number of PSFCHs that meet the preset criterion) equals k, the operation Figure 11 S2100 may be executed. When the incremented cumulative count (e.g., the number of PSFCHs that meet the preset criterion) is less than k, the operation S2010 of measuring the RSRP or SINR of the next PSFCH (e.g., the (n + 1)th PSFCH) may be executed.

[0210] Even when it is determined that the nth PSFCH does not meet the preset criterion, the operation S2010 of measuring the RSRP or SINR of the next PSFCH (e.g., the (n + 1)th PSFCH) may be executed.

[0211] As a reference, there may be various criteria, and the method of selecting k PSFCHs based on each criterion may be as follows.

[0212] 1) When k PSFCHs among all PSFCHs having an RSRP or SINR less than a preset reference value are accumulated, the selection operation may end. Specifically, a HARQ ACK / NACK determination operation may be performed on the PSFCHs having an RSRP or SINR less than the preset reference value, while a HARQ ACK / NACK determination operation may not be performed on the PSFCHs having an RSRP or SINR greater than or equal to the preset reference value. The results of the determination operations on some PSFCHs may be considered representative of the determination operations on all PSFCHs. According to this method, the data rate may be improved by taking advantage of the fact that when the channel state at the receiving terminal is better than a specific threshold, it is less likely that the PSFCH feedback is NACK.

[0213] 2) When k PSFCHs among all PSFCHs having an RSRP or SINR greater than a preset reference value are accumulated, the selection operation may end. Specifically, a HARQ ACK / NACK determination operation may be performed on PSFCHs having an RSRP or SINR greater than the preset reference value, while a HARQ ACK / NACK determination operation may not be performed on PSFCHs having an RSRP or SINR less than or equal to the preset reference value. The result of the determination operation on some PSFCHs may be considered to represent the determination operation on all PSFCHs. According to this method, the data rate can be increased by taking advantage of the fact that when the channel state of the receiving terminal is worse than a specific threshold, the PSFCH feedback is likely to be NACK.

[0214] 3) When k PSFCHs among all PSFCHs having an RSRP or SINR greater than a first reference value and less than a second reference value are accumulated, the selection operation may end. Here, the second reference value may be different from the first reference value. Specifically, a HARQ ACK / NACK determination operation may be performed only on PSFCHs having an RSRP or SINR greater than the first reference value and less than the second reference value. The result of the determination operation on some PSFCHs may be considered to represent the determination operation on all PSFCHs. According to this method, the data rate can be increased by using the above two methods.

[0215] Here, each of k and the reference value may be preset by the manufacturer or user of the terminal 53 based on at least one of the channel state of the terminal 53, the performance of the terminal 53, and the total number of PSFCHs. Moreover, for example, when the base station (e.g., Figure 8 the base station 51 in ) sets up the sidelink, the terminal 53 may be guided to set k to any one of values within a specific range.

[0216] Return reference Figure 11 , when k PSFCHs are selected at operation S2000, at operation S2100, the selected k PSFCHs may be sorted in ascending order based on the measured RSRP or SINR.

[0217] Specifically, the processor 150 may sort the k PSFCHs in ascending order based on the RSRP or SINR of each PSFCH measured by the transceiver 160.

[0218] When the sorting of the k PSFCHs in ascending order is completed, at operation S2200, it may be sequentially determined whether the k PSFCHs sorted in ascending order are HARQ ACK or HARQ NACK, and at operation S2300, it may be determined whether to retransmit the PSSCH based on the determination result.

[0219] As a reference, since operations S2100 to S2300 may correspond to operations S1100 to S1300 described above, their detailed descriptions are omitted. Figure 9 and Figure 10 described operations S1100 to S1300, their detailed descriptions are omitted.

[0220] As described above, according to the example embodiment, a method for determining the PSFCH of a terminal can be performed. Hereinafter, a wireless communication device implemented according to the embodiment will be described with reference to Figure 13 a description of a wireless communication device implemented according to the embodiment.

[0221] Figure 13 FIG. 201 is a block diagram of a wireless communication device 201 according to an embodiment.

[0222] As a reference, Figure 13 the wireless communication device 201 can be applied to a base station, such as Figure 2 the base station 51 in Figure 2 ; an eNB, a gNB, and an access point (AP), or a terminal, such as Figure 13 the terminal 53 or the terminal 55 in

[0223] Specifically, Figure 13 FIG. 201 implemented in the network environment 200 is shown.

[0224] The wireless communication device 201 may include a bus 210, a processor 220, a memory 230, an input / output (I / O) interface 250, a display module 260, and a communication interface 270. In another case, the wireless communication device 201 may omit at least one of the above components, or may further include at least one other component. However, for simplicity, the example embodiment relates to an example in which the wireless communication device 201 includes the above components.

[0225] The bus 210 may connect the processor 220, the memory 230, the I / O interface 250, the display module 260, and the communication interface 270 to each other. Therefore, signals, such as control messages and / or data, can be exchanged and transmitted between the processor 220, the memory 230, the I / O interface 250, the display module 260, and the communication interface 270 via the bus 210.

[0226] The processor 220 may include at least one of a central processing unit (CPU), an application processor (AP), and a communication processor (CP). Moreover, the processor 220 may perform operations or data processing operations related to the control and / or communication with other components of the wireless communication device 201. In an embodiment, the processor 220 may be a component including Figure 7 the functions of the processor 150.

[0227] The memory 230 may include volatile memory and / or non-volatile memory. In addition, the memory 230 may store commands or instructions or data associated with other components in the wireless communication device 201.

[0228] Additionally, the memory 230 may store software and / or a program 240. The program 240 may include, for example, a kernel 241, middleware 243, an application programming interface (API) 245, an application program 247 (also referred to as an “application”), and network access information 249.

[0229] For reference, at least some of the kernel 241, middleware 243, and API 245 may be referred to as an operating system (OS). Moreover, in an embodiment, the memory 230 may be a component including Figure 7 the functions of the memory 170.

[0230] For example, the I / O interface 250 may send commands or data received from a user or another external device to other components of the wireless communication device 201. In addition, the I / O interface 250 may output commands or data received from other components of the wireless communication device 201 to a user or another external device.

[0231] The display module 260 may include, for example, a liquid crystal display (LCD), a light-emitting diode (LED) display, an organic LED (OLED) display, a microelectromechanical systems (MEMS) display, or an electronic paper display.

[0232] Additionally, the display module 260 may display various contents to a user, such as text, images, videos, icons, or symbols. The display module 260 may include a touch screen and may receive touches, gestures, proximity, or hovering input by using, for example, an electronic pen or a user's body part.

[0233] The communication interface 270 can establish communication between the wireless communication device 201 and an external device (e.g., electronic devices 202 and 204 or server 206). For example, the communication interface 270 can be connected to the network 262 via wireless communication or wired communication and can communicate with an external device (e.g., electronic device 204 or server 206). Additionally, the communication interface 270 can communicate with an external device (e.g., electronic device 202) via wireless communication 264. Moreover, the communication interface 270 can be a component that includes Figure 7 the functions of the transceiver 160.

[0234] As a reference, the wireless communication 264 can be a cellular communication protocol and can use at least one of, for example, NR, LTE, LTE-A, CDMA, WCDMA, Universal Mobile Telecommunications System (UMTS), Wireless Broadband (WiBro), and GSM. Additionally, the wired communication can include at least one of, for example, Universal Serial Bus (USB), High-Definition Multimedia Interface (HDMI), Recommended Standard 232 (RS-232), and Plain Old Telephone Service (POTS).

[0235] Moreover, the network 262 as a telecommunications network can include at least one of, for example, a computer network (e.g., Local Area Network (LAN) or Wide Area Network (WAN)), the Internet, and a telephone network.

[0236] Furthermore, each of the electronic devices 202 and 204 as external devices can be of the same type or different types from the wireless communication device 201. Also, the server 206 can include a group of at least one server.

[0237] As a reference, all or some of the operations performed by the wireless communication device 201 can be performed by other external devices, e.g., electronic devices 202 and 204 or server 206.

[0238] Additionally, when the wireless communication device 201 needs to perform a function or service automatically or upon request, the wireless communication device 201 can perform the function or service itself, or can request other external devices (e.g., electronic devices 202 and 204 or server 206) to perform part of the function or service. Also, other external devices (e.g., electronic devices 202 and 204 or server 206) can perform the requested function or service and can send the result to the wireless communication device 201. In this case, the wireless communication device 201 can perform the function or service based on the received result or by performing additional processing on the received result.

[0239] For the above mechanism, for example, cloud computing technology, distributed computing technology, or client-server computing technology can be applied to the wireless communication device 201.

[0240] According to the above embodiments, the excess of the PSFCH reception capability and the overload of the operation of determining whether the PSFCH is an ACK or a NACK can be solved by sending a signaling for the maximum PSFCH transceiver capability and using an effective ACK / NACK determination method for the PSFCH. Therefore, the performance and operation efficiency of the terminal can be improved.

[0241] Although the embodiments have been specifically shown and described, it should be understood that various changes in form and details can be made without departing from the spirit and scope of the appended claims.

Claims

1. A terminal configured to perform communication between a vehicle and the outside world, the terminal comprising: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to: control the transceiver to measure the reference signal reception power or signal-to-interference-plus-noise ratio of k physical sidelink feedback channels among a plurality of physical sidelink feedback channels received during a transmission time interval, where k is an integer greater than 1; sort the k physical sidelink feedback channels in ascending order based on the reference signal reception power or the signal-to-interference-plus-noise ratio; control the transceiver to perform such an order determination: whether the k physical sidelink feedback channels sorted in ascending order are hybrid automatic repeat request acknowledgments or hybrid automatic repeat request negative acknowledgments; and determine whether to retransmit a physical sidelink shared channel based on the order determination.

2. The terminal according to claim 1, wherein when the order determination indicates that the m-th physical sidelink feedback channel among the sorted k physical sidelink feedback channels is a hybrid automatic repeat request acknowledgment, the processor is further configured to: determine whether m is less than k; and control the transceiver to continue performing the order determination on the remaining physical sidelink feedback channels among the sorted k physical sidelink feedback channels, or control the transceiver to end the order determination on the sorted k physical sidelink feedback channels, where m is a positive integer less than or equal to k.

3. The terminal according to claim 2, wherein when m is less than k, the processor is further configured to control the transceiver to continue performing the order determination on the remaining physical sidelink feedback channels among the sorted k physical sidelink feedback channels.

4. The terminal according to claim 2, wherein when m is equal to k, the processor is further configured to control the transceiver to end the order determination, and determine whether to continue measuring the reference signal reception power or signal-to-interference-plus-noise ratio of additional physical sidelink feedback channels based on whether there is at least one physical sidelink feedback channel among the plurality of physical sidelink feedback channels on which the order determination has not been performed.

5. The terminal according to claim 4, wherein when there is at least one physical sidelink feedback channel among the plurality of physical sidelink feedback channels on which the order determination has not been performed, the processor is further configured to control the transceiver to continue measuring the reference signal reception power or signal-to-interference-plus-noise ratio of the additional physical sidelink feedback channels, and when the order determination is performed on all physical sidelink feedback channels among the plurality of physical sidelink feedback channels, the processor is further configured to control the transceiver to end the order determination.

6. The terminal according to claim 1, wherein when it is determined that the m-th physical sidelink feedback channel among the sorted k physical sidelink feedback channels is a hybrid automatic repeat request negative acknowledgment, the processor is further configured to: Control the transceiver to interrupt the determination of the order of the remaining physical sidelink feedback channels among the sorted k physical sidelink feedback channels; and Retransmit the physical sidelink shared channel, where m is a positive integer less than or equal to k.

7. The terminal according to claim 1, wherein, k is set based on at least one of the channel state of the terminal, the performance of the terminal, and the total number of the plurality of physical sidelink feedback channels.

8. A terminal configured to perform communication between a vehicle and the outside world, the terminal comprising: a transceiver configured to transmit and receive one or more wireless signals; and a processor configured to: Control the transceiver to measure the reference signal received power or signal-to-interference-plus-noise ratio of a plurality of physical sidelink feedback channels received during one transmission time interval; Select k physical sidelink feedback channels that meet a preset criterion from the plurality of physical sidelink feedback channels, where k is an integer greater than 1; Sort the selected k physical sidelink feedback channels in ascending order based on the reference signal received power or the signal-to-interference-plus-noise ratio; Control the transceiver to perform such an order determination: whether the k physical sidelink feedback channels sorted in ascending order are hybrid automatic repeat request acknowledgments or hybrid automatic repeat request negative acknowledgments; and Based on the order determination, determine whether to retransmit the physical sidelink shared channel.

9. The terminal according to claim 8, wherein, When the reference signal received power or signal-to-interference-plus-noise ratio is less than a preset reference value, the preset criterion is met.

10. The terminal according to claim 8, wherein, When the reference signal received power or signal-to-interference-plus-noise ratio is greater than a preset reference value, the preset criterion is met.

11. The terminal according to claim 8, wherein, When the reference signal received power or signal-to-interference-plus-noise ratio is greater than a first reference value and less than a second reference value, the preset criterion is met, where the second reference value is different from the first reference value.

12. The terminal according to claim 8, wherein, When it is determined that the m-th physical sidelink feedback channel among the sorted k physical sidelink feedback channels is a hybrid automatic repeat request acknowledgment, the processor is further configured to: Determine whether m is less than k; and Control the transceiver to continue the order determination for the remaining physical sidelink feedback channels among the sorted k physical sidelink feedback channels, or control the transceiver to end the order determination, where m is a positive integer less than or equal to k.

13. The terminal according to claim 12, wherein, When m is less than k, the processor is further configured to control the transceiver to continue the order determination for the remaining physical sidelink feedback channels.

14. The terminal according to claim 12, wherein, When m is equal to k, the processor is further configured to control the transceiver to end the order determination, and determine whether to continue selecting additional physical sidelink feedback channels based on whether there is at least one physical sidelink feedback channel among the multiple physical sidelink feedback channels for which the order determination has not been performed.

15. The terminal according to claim 14, wherein, when there is at least one physical sidelink feedback channel among the multiple physical sidelink feedback channels for which the order determination has not been performed, the processor is further configured to select the additional physical sidelink feedback channel, and when the order determination is performed on all the physical sidelink feedback channels among the multiple physical sidelink feedback channels, the processor is further configured to control the transceiver to end the order determination.

16. The terminal according to claim 8, wherein, when it is determined that the m-th physical sidelink feedback channel among the sorted k physical sidelink feedback channels is a hybrid automatic repeat request negative acknowledgment, the processor is further configured to: control the transceiver to interrupt the order determination of the remaining physical sidelink feedback channels among the sorted k physical sidelink feedback channels; and retransmit the physical sidelink shared channel, where m is a positive integer less than or equal to k.

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