Time domain overlap management in direct communication link

Abstract

The present document relates to a communication method considering a time domain overlapping situation between signals transmitted through a direct communication link, and a user device therefor. To this end, the communication method comprises: receiving, by a second user equipment (UE), a physical control channel through a direct communication link and a physical shared channel corresponding to the physical control channel in a first time resource from a first UE performing communication through the direct communication link; and receiving a reference signal (RS) for beam management of the direct communication link. In this case, for the physical control channel / physical shared channel, a second time resource for retransmission is reserved on the basis of control information transmitted by the physical control channel, and the receiving of the RS includes receiving a standalone RS without data transmission through a third time resource. In the present invention, when the third time resource overlaps with the first time resource / the second time resource, a reception beam is determined on the basis of the priority between the standalone RS and the physical control channel / physical shared channel.

Description

Time domain overlap management in direct communication links

[0001] The following description relates to communication using a direct communication link between user equipment (UE), and more specifically, to a communication method and a user equipment for the same that take into account a situation in which overlap occurs in the time domain between signals transmitted via the direct communication link.

[0002] Wireless communication systems utilize various technologies, including LTE, LTE-Advanced, and WiFi, and 5G is included. The three main usage scenarios for 5G include (1) Enhanced Mobile Broadband (eMBB), (2) Massive Machine Type Communication (mMTC), and (3) Ultra-reliable and Low Latency Communications (URLLC). Some use cases may require optimization across multiple areas, while others may focus on just a single Key Performance Indicator (KPI). 5G supports these diverse use cases in a flexible and reliable manner.

[0003] Figure 1 shows the structure of a system for 5G communication.

[0004] Referring to FIG. 1, a Next Generation - Radio Access Network (NG-RAN) may include a base station (20) that provides user plane and control plane protocol termination to a UE (10). For example, the base station (20) may include a next generation Node B (gNB) and / or an evolved Node B (eNB). For example, the UE (10) may be fixed or mobile, and may be referred to by other terms such as a terminal, a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), a wireless device, etc. For example, the base station may be a fixed station that communicates with the UE (10), and may be referred to by other terms such as a base transceiver system (BTS), an access point, etc.

[0005] The example of Fig. 1 illustrates a case that includes only gNB. The base stations (20) can be connected to each other via Xn interfaces. The base stations (20) can be connected to a 5th generation core network (5G Core Network: 5GC) via an NG interface. More specifically, the base station (20) can be connected to an access and mobility management function (AMF) (30) via an NG-C interface, and can be connected to a user plane function (UPF) (30) via an NG-U interface.

[0006]

[0007] In the system for 5G communication as described above, a connection may be made between a UE (10) and a gNB via a Uu interface, and a connection may be made between UEs (10) via a PC5 interface, and a link via PC5 may be referred to as a side link. In the 5G communication system and its successor next-generation mobile communication, a communication method using a high frequency band (Frequency Range 2 or FR2) of 24 GHz or higher, unlike the existing communication frequency band (Frequency Range 1 or FR1), is being discussed.

[0008] In this type of FR2 communication method, it is required to form beams of signals and communicate them considering high path loss, and a method using RS (Reference Signal) is required for efficient beam management of the side link.

[0009] However, the RS transmitted for beam management in this way may overlap with the data channel / control channel of the side link in the time domain, and a method for efficiently managing this situation is required.

[0010] In order to solve the above-described problem, one aspect of the present invention proposes a method for performing communication by efficiently managing overlap occurring in the time domain between signals transmitted through a direct communication link between UEs, and a user device therefor.

[0011] The technology proposed below is assumed to be applicable not only to the current 5G system but also to 6G and subsequent mobile communication systems, and therefore, the term 'side link' used in 5G can be referred to as a 'direct communication link' between UEs, and the concept of 'direct communication link' is assumed to be used as a term to refer to a link adopted to correspond to the side link between 5G UEs in 6G and subsequent standards.

[0012] In addition, terms such as PSSCH (Physical Sidelink Shared Channel), PSCCH (Physical Sidelink Control Channel), and PSFCH corresponding to data channels used in 5G may be referred to as terms such as 'physical shared channel', 'physical control channel', and 'physical feedback channel' transmitted through the above-described direct communication link.

[0013] In one aspect of the present invention, when RS transmission time resources for beam management of a direct communication link between UEs overlap with one or more time resources of the above-described physical control channel or physical shared channel, a receiving operation according to priority between signals is intended to be specified.

[0014] At this time, the RS transmitted may correspond to the CSI (Channel Status Information) - RS transmitted in 5G, but there is no need to exclude other terms used in correspondence to the RS transmitted for beam management of the corresponding frequency band in 6G and subsequent standards.

[0015] The problems to be solved by the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned can be clearly understood by a person having ordinary skill in the technical field to which the present invention belongs from the description below.

[0016] In one aspect of the present invention for solving the above-described problem, in a communication method of a second UE performing communication with a first user equipment (UE) through a direct communication link in a mobile communication system, the method comprises: receiving a physical control channel from the first UE through the direct communication link in a first time resource; receiving a physical shared channel corresponding to the physical control channel through the direct communication link in the first time resource; And, a communication method is proposed, characterized in that it includes receiving an RS (Reference Signal) for beam management of the direct communication link, wherein, for at least one of the physical control channel and the physical shared channel, a second time resource for retransmission is reserved based on control information transmitted by the physical control channel, and receiving the RS includes receiving a standalone RS that does not accompany data transmission through a third time resource, and when the third time resource overlaps with the first time resource or the second time resource, a reception beam is determined based on a priority between the standalone RS and at least one of the physical control channel and the physical shared channel.

[0017] When the priority of the first type of signal among the standalone RS and at least one of the physical control channel or the physical shared channel is high, the second beam for receiving the second type of signal among the standalone RS and at least one of the physical control channel or the physical shared channel can be received assuming that it is quasi co-located (QCL) with the first beam for receiving the first type of signal.

[0018] At this time, the first beam and the second beam can be received assuming that they are QCL of the spatial reception parameter sharing type.

[0019] Meanwhile, in the first situation, the first type signal may correspond to the standalone RS, and the second type signal may correspond to one or more of the physical control channel or the physical shared channel.

[0020] On the other hand, in the second situation, the first type signal may correspond to at least one of the physical control channel or the physical shared channel, and the second type signal may correspond to the standalone RS.

[0021] Additionally, when the third time resource overlaps with the first time resource, the first type signal may correspond to the standalone RS, and the second type signal may correspond to at least one of the physical control channel or the physical shared channel.

[0022] In contrast, when the third time resource overlaps with the second time resource, the first type signal may correspond to at least one of the physical control channel or the physical shared channel, and the second type signal may correspond to the standalone RS.

[0023] In addition, if the third time resource overlaps with the second time resource and the second UE successfully decodes at least one of the physical control channel or the physical shared channel received in the first time resource, the first type signal may correspond to at least one of the physical control channel or the physical shared channel, and the second type signal may correspond to the standalone RS.

[0024] In addition, if the third time resource overlaps with the second time resource and the second UE fails to successfully decode at least one of the physical control channel or the physical shared channel received in the first time resource, the first type signal may correspond to at least one of the physical control channel or the physical shared channel, and the second type signal may correspond to the standalone RS.

[0025] Additionally, the standalone RS may have a higher priority than the physical control channel and a lower priority than the physical shared channel.

[0026] In addition, it may additionally include receiving control information indicating a priority between the physical shared channel and the standalone RS through the physical control channel.

[0027] The above physical control channel includes a PSCCH (Physical Sidelink Control Channel), the above physical shared channel includes a PSSCH (Physical Sidelink Shared Channel), and the above standalone RS may include a standalone CSI (Channel Status Information) - RS, but need not be limited to the names of such 5G systems.

[0028] Meanwhile, in another aspect of the present invention for solving the above-described problem, a second user equipment (UE) that performs communication with a first user equipment (UE) through a direct communication link in a mobile communication system comprises at least one processor; and at least one computer memory that can be operably connected to the at least one processor and stores instructions that, when executed, cause the at least one processor to perform operations, wherein the operations include: receiving a physical control channel through the direct communication link from the first UE in a first time resource; receiving a physical shared channel corresponding to the physical control channel through the direct communication link in the first time resource; And, a user device is proposed, characterized in that it includes receiving an RS (Reference Signal) for beam management of the direct communication link, wherein, for at least one of the physical control channel and the physical shared channel, a second time resource for retransmission is reserved based on control information transmitted by the physical control channel, and receiving the RS includes receiving a standalone RS that does not accompany data transmission through a third time resource, and when the third time resource overlaps with the first time resource or the second time resource, a reception beam is determined based on a priority between the standalone RS and at least one of the physical control channel and the physical shared channel.

[0029] According to the embodiments of the present invention as described above, it is possible to efficiently manage overlap occurring in the time domain between signals transmitted through a direct communication link between UEs.

[0030] Specifically, when the RS transmission time resource for beam management of a direct communication link between UEs overlaps with the time resource of one or more of the above-described physical control channels or physical shared channels, the reception beam according to the priority between signals can be specified, thereby maintaining the reception quality of a signal appropriate to the situation.

[0031] The effects that can be obtained from the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by a person having ordinary skill in the art to which the present invention belongs from the description below.

[0032] Figure 1 shows the structure of a system for 5G communication.

[0033] FIG. 2 is a diagram for explaining channels that can be used in sidelink communication according to embodiments of the present invention.

[0034] FIG. 3 is a diagram for explaining the concept of blind retransmission resource reservation assumed by embodiments of the present invention.

[0035] FIG. 4 is a diagram for explaining the RS transmission concept for beam management assumed in embodiments of the present invention.

[0036] FIG. 5 is a diagram for explaining a management method when SA-RS and PSCCH / PSSCH overlap in the time domain according to one embodiment of the present invention.

[0037] FIG. 6 is a diagram for explaining a concept of receiving according to priority when an SA-RS and a physical control channel and / or a physical shared channel overlap in the time domain according to one embodiment of the present invention.

[0038] FIG. 7 is a diagram for explaining a method for explaining the priority of a received signal according to a direct link communication situation according to one embodiment of the present invention.

[0039] FIG. 8 is a diagram for explaining a method for explaining the priority of a received signal depending on whether a control channel / shared channel is initially transmitted or retransmitted according to one embodiment of the present invention.

[0040] FIG. 9 is a diagram for explaining a method of considering different priorities of a physical control channel / physical shared channel according to one embodiment of the present invention.

[0041] FIG. 10 is a diagram for explaining a method of dynamically indicating priority information through SCI according to one embodiment of the present invention.

[0042] FIG. 11 is a diagram for explaining a process of establishing a unicast link for performing direct communication between UEs according to one embodiment of the present invention.

[0043] Figure 12 illustrates a wireless device to which the present technology can be applied.

[0044] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in various different forms and is not limited to the embodiments described herein. In addition, in the drawings, parts irrelevant to the description have been omitted to clearly explain the present invention, and similar parts have been designated with similar reference numerals throughout the specification.

[0045] Throughout the specification, whenever a part is said to "include" a component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise stated.

[0046]

[0047] As described above, one aspect of the present invention proposes a method for performing communication by efficiently managing the time-domain overlap between signals transmitted via a direct communication link between UEs, and a user equipment for the same. The proposed technology is assumed to be applicable not only to the current 5G system, but also to 6G and subsequent next-generation mobile communication systems. However, for ease of understanding, the following description will assume the current 5G system to avoid confusion.

[0048] First, we will look at channels that can be used in sidelink communication according to embodiments of the present invention.

[0049] FIG. 2 is a diagram for explaining channels that can be used in sidelink communication according to embodiments of the present invention.

[0050] The embodiment of FIG. 2 can be combined with various embodiments of the present invention. In various embodiments of the present invention, the "transmission mode" may be referred to as a "mode" or a "resource allocation mode." Hereinafter, for convenience of explanation, the transmission mode in LTE may be referred to as the LTE transmission mode, and the transmission mode in NR may be referred to as the NR resource allocation mode.

[0051] Specifically, (a) of FIG. 2 represents UE operations related to LTE transmission mode 1, LTE transmission mode 3, or NR resource allocation mode 1. For example, LTE transmission mode 1 can be applied to general SL communication, and LTE transmission mode 3 can be applied to V2X communication.

[0052] Meanwhile, (b) of FIG. 2 shows UE operation related to LTE transmission mode 2 or LTE transmission mode 4 or NR resource allocation mode 2.

[0053] Referring to (a) of FIG. 2, in LTE transmission mode 1, LTE transmission mode 3, or NR resource allocation mode 1, the base station may schedule SL resources to be used by the UE for SL transmission (S8000). For example, the base station may transmit information related to SL resources and / or information related to UL resources to the first UE. The UL resources may include PUCCH resources and / or PUSCH resources. In addition, the UL resources may be resources for reporting SL HARQ feedback to the base station.

[0054] A first UE may receive information related to a dynamic grant (DG) resource and / or information related to a configured grant (CG) resource from a base station. The CG resource may include a CG type 1 resource or a CG type 2 resource. In this specification, a DG resource may be a resource that a base station configures / allocates to the first UE via downlink control information (DCI). In addition, in this specification, a CG resource may be a (periodic) resource that a base station configures / allocates to the first UE via DCI and / or an RRC message. For example, in the case of a CG type 1 resource, the base station may transmit an RRC message including information related to the CG resource to the first UE. In the case of a CG type 2 resource, the base station may transmit an RRC message including information related to the CG resource to the first UE, and the base station may transmit a DCI related to activation or release of the CG resource to the first UE.

[0055] In step S8010, the first UE may transmit a PSCCH (e.g., Sidelink Control Information (SCI) or 1st-stage SCI) to the second UE based on the resource scheduling. In step S8020, the first UE may transmit a PSSCH (e.g., 2nd-stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second UE. In step S8030, the first UE may receive a PSFCH (Physical Sidelink Feedback Channel) related to the PSCCH / PSSCH from the second UE. For example, HARQ feedback information (e.g., NACK information or ACK information) may be received from the second UE via the PSFCH. In step S8040, the first UE may transmit / report HARQ feedback information to the base station via a PUCCH or a PUSCH. For example, the HARQ feedback information reported to the base station may be information generated by the first UE based on the HARQ feedback information received from the second UE. In addition, the HARQ feedback information reported to the base station may be information generated by the first UE based on a rule set in advance. The DCI may be DCI for scheduling the SL. The format of the DCI may be DCI format 3_0 or DCI format 3_1.

[0056] [Table 1] shows an example of DCI for SL scheduling.

[0057] Format 3_0- Resource pool index -roof (log2I) bits, whereIis the number of resource pools for transmission configured by the higher layer parametersl-TxPoolScheduling.- Time gap - 3 bits determined by higher layer parametersl-DCI-ToSL-Trans- HARQ process number - 4 bits- New data indicator - 1 bit- Lowest index of the subchannel allocation to the initial transmission -roof (log2(N SL subChannel)) bits- SCI format 1-A fields:- Frequency resource assignment.- Time resource assignment.- PSFCH-to-HARQ feedback timing indicator -roof (log2N ft_timing ) bits, where N ft_timingis the number of entries in the higher layer parametersl-PSFCH-ToPUCCH- PUCCH resource indicator - 3 bits.- Configuration index - 0 bit if the UE is not configured to monitor DCI format 3_0 with CRC scrambled by SL-CS-RNTI; otherwise 3 bits. If the UE is configured to monitor DCI format 3_0 with CRC scrambled by SL-CS-RNTI, this field is reserved for DCI format 3_0 with CRC scrambled by SL-RNTI.- Counter sidelink assignment index - 2 bits- 2 bits if the UE is configured withpdsch-HARQ-ACK-Codebook = dynamic- 2 bits if the UE is configured withpdsch-HARQ-ACK-Codebook = semi-static- Padding bits, if requiredFormat 3_1- Timing offset - 3 bits determined by higher layer parametersl-TimeOffsetEUTRA- Carrier indicator -3 bits.- Lowest index of the subchannel allocation to the initial transmission - roof (log2(N SLsubChannel) bits.- Frequency resource location of initial transmission and retransmission- Time gap between initial transmission and retransmission- SL index - 2 bits- SL SPS configuration index - 3 bits.- Activation / release indication - 1 bit.

[0058]

[0059] Referring to (b) of FIG. 2, in LTE transmission mode 2, LTE transmission mode 4, or NR resource allocation mode 2, the UE can determine SL transmission resources within SL resources configured by the base station / network or preset SL resources. The configured SL resources or preset SL resources may be a resource pool. For example, the UE can autonomously select or schedule resources for SL transmission. The UE can perform SL communication by selecting resources within the configured resource pool. For example, the UE can perform sensing and resource (re)selection procedures to select resources within a selection window. The sensing may be performed on a subchannel basis.

[0060] In step S8010, a first UE that has selected a resource within a resource pool can transmit a PSCCH (e.g., Sidelink Control Information (SCI) or 1st-stage SCI) to a second UE using the resource. In step S8020, the first UE can transmit a PSSCH (e.g., 2nd-stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second UE. In step S8030, the first UE can receive a PSFCH related to the PSCCH / PSSCH from the second UE.

[0061] Referring to (a) or (b) of FIG. 2, a first UE may transmit an SCI to a second UE on a PSCCH. Alternatively, the first UE may transmit two consecutive SCIs (e.g., 2-stage SCIs) to the second UE on the PSCCH and / or the PSSCH. In this case, the second UE may decode the two consecutive SCIs (e.g., 2-stage SCIs) to receive the PSSCH from the first UE. In this specification, an SCI transmitted on a PSCCH may be referred to as a 1st SCI, a 1st SCI, a 1st-stage SCI, or a 1st-stage SCI format, and an SCI transmitted on a PSSCH may be referred to as a 2nd SCI, a 2nd SCI, a 2nd-stage SCI, or a 2nd-stage SCI format. For example, a 1st-stage SCI format may include SCI format 1-A, and a 2nd-stage SCI format may include SCI format 2-A and / or SCI format 2-B.

[0062]

[0063] FIG. 3 is a diagram for explaining the concept of blind retransmission resource reservation assumed by embodiments of the present invention.

[0064] In 5G NR, resources for performing retransmission a certain number of times can be reserved and allocated in advance to increase the transmission success probability of PSCCH / PSSCH, which can be referred to as blind retransmission resource reservation.

[0065] Specifically, the format 1-A of the above-described SCI can support resource reservation for blind retransmission of the same data (e.g., TB (Transport Block)) up to three times by using the sl-MaxNumPerReserve parameter.

[0066] [Formula 1]

[0067] sl-MaxNumPerReserve (Nmax ) = {2, 3}

[0068] Specifically, looking at time domain resource allocation for PUCCH / PSSCH transmission, the TDRA (Time Domain Resource Assignment) field for resource allocation can be defined as follows.

[0069] TDRA fieldIndicates time RIV (TRIV) within max 32 slotsIf N=1, TRIV=0Initial slot (t0) is the slot where the SCI 1-A received.elseif N=2, TRIV=t1where 1≤t1≤31elseif N=3, TRIV=t1,t2where 1≤t1≤30, t1≤t2≤31Resource reservation (different TBs)Resource reservation period is indicated

[0070] Based on this, referring to FIG. 3, the time resource for the initial transmission of the PSCCH / PSSCH is determined and transmitted in a specific slot (m1) within the first period (T1), and the time resource for retransmission of the same data (e.g., TB) within the same period can be reserved in slots (m2) and (m3) for the PSCCH / PSSCH (S310a, S310b). In FIG. 3, the resource interval for retransmission is indicated as a window W. This resource allocation pattern can be repeated in a similar manner to the first period (T1) in the second period (T2) for subsequent data (e.g., TB) (S330). In FIG. 3, the time resources for initial transmission in the second cycle are allocated based on the time resources for initial transmission in the first cycle (S320a), and the resources for retransmission are also allocated correspondingly in the second cycle (S320b, 320c).

[0071] The cycle of resource allocation described above in 5G NR can be determined by the following parameters.

[0072] [Formula 2]

[0073] Resource reservation period - roof (log2N rev_period ) bits

[0074] Here, if the upper layer parameter sl-MultiReserveResource is configured, N rev_period Indicates the number of entries specified in the upper layer parameter sl-ResourceReservePeriodList, and can be specified as 0 bits in other cases.

[0075] FIG. 4 is a diagram for explaining the RS transmission concept for beam management assumed in embodiments of the present invention.

[0076] Beam management in the 5G sidelink can be performed via the Synchronization Signal Block (SSB) and / or CSI-RS. Specifically, SSB and CSI-RS can be utilized during initial beam pairing operations, while beam management can primarily be performed via CSI-RS after a unicast link is established.

[0077] Meanwhile, CSI-RS can be viewed as an RS transmitted along with PSCCH / PSSCH, and discussions on improving 5G include not only this CSI-RS but also the additional transmission of standalone CSI-RS that does not accompany PSCCH / PSSCH. In the following description, standalone CSI-RS will be referred to as SA-CSI-RS, or simply as SA-RS to emphasize the standalone form of the RS itself.

[0078] The specific transmission method for SA-RS has not yet been precisely defined in 5G. However, the following embodiments of the present invention assume that resources for SA-RS transmission are predefined and transmitted through a designated resource pool.

[0079] In addition, the SA-RS can be transmitted periodically as illustrated in Fig. 4, and the description will assume a form in which it can be transmitted through multiple beams in one transmission cycle. In some cases, the SA-RS can be transmitted through multiple beams within one slot. In this case, the frequency band in which the SA-RS is transmitted may be the same as or different from the frequency band in which the PSCCH / PSSCH is transmitted.

[0080] If UE 1 periodically transmits the SA-RS described above as a transmitting UE (Tx UE), UE 2 corresponding to a receiving UE (Rx UE) can measure the RSRP of the SA-RS and report beam performance to UE 1 through a MAC (Medium Access Control) CE (Control Element).

[0081]

[0082] FIG. 5 is a diagram for explaining a management method when SA-RS and PSCCH / PSSCH overlap in the time domain according to one embodiment of the present invention.

[0083] As described above, performing communication through a direct communication link between UEs may include UE 2 (Rx UE) receiving a physical control channel and / or a physical shared channel through the direct communication link from UE 1 (Tx UE) (520).

[0084] In one embodiment of the present invention, it is assumed that a second time resource (T2a, T2b) for retransmission is reserved (530) based on control information transmitted by the physical control channel for at least one of the physical control channel and / or the physical shared channel as described above in FIG. 3, thereby increasing the reception probability of the direct communication link.

[0085] In the following description, the time resource for initial transmission is referred to as the first time resource (T1) to distinguish it from the second time resource reserved for retransmission as described above.

[0086] In addition, the present embodiment includes receiving an RS for beam management of a direct communication link (510). Here, receiving an RS (510) includes receiving an SA-RS that does not involve data transmission as described above with respect to FIG. 4, and in the embodiment of FIG. 5, the time resource for receiving the SA-RS in this manner is referred to as a 'third time resource (T3)'.

[0087] SA-RS can be transmitted repeatedly (540) with a period as described above with respect to FIG. 4, and FIG. 5 illustrates an example in which the third time resource is set multiple times (T3a, T3b, T3c, T3d) accordingly.

[0088] In this situation, embodiments of the present invention propose a processing method in the case (550) where the third time resource (T3) overlaps with the first time resource (T1) and / or the second time resource (T2), and FIG. 5 illustrates a first situation where the third time resource (T3b) for SA-RS transmission overlaps with the second time resource (T2b) reserved for retransmission of a physical control channel and / or a physical shared channel, and a second situation where the third time resource (T3d) for SA-RS transmission overlaps with the first time resource (T1b) reserved for initial transmission of a physical control channel and / or a physical shared channel.

[0089] In one embodiment of the present invention, when SA-RS and physical control channel and / or physical shared channel time resources overlap, reception is proposed based on the priority of both signals, and the concept of 'reception based on priority' will be described in more detail below.

[0090] FIG. 6 is a diagram for explaining a concept of receiving according to priority when an SA-RS and a physical control channel and / or a physical shared channel overlap in the time domain according to one embodiment of the present invention.

[0091] As described above with respect to FIG. 5, in one embodiment of the present invention, a signal having a high priority among the SA-RS and the physical control channel and / or the physical shared channel is first determined (S610). For convenience of explanation below, the signal having a high priority is referred to as a 'first type signal', and the signal having a low priority among the two types of signals is referred to as a second type signal.

[0092] In this embodiment, the concept of receiving signals according to priority is proposed by assuming that a second beam for receiving a second type of signal with a lower priority is quasi-co-located (QCL) with a first beam for receiving a first type of signal.

[0093] 5G NR defines the following four types of QCL:

[0094] QCL TypeDescriptionQCL-TypeADoppler shift, Doppler spread, average delay, delay spreadQCL-TypeBDoppler shift, Doppler spreadQCL-TypeCAverage delay, Doppler shiftQCL-TypeDSpatial Rx parameter

[0095] In the present embodiment, the meaning of reception assuming that the second beam for receiving the second type signal with a low priority is QCL with the first beam for receiving the first type signal with a high priority is preferably assuming QCL of type D among the four QCL types of [Table 3], and it is also preferable to receive assuming QCL of a type in which spatial reception parameters are shared in the standard following 5G NR.

[0096] In this way, for the second type signal with lower priority, reception performance may be degraded as it is forcibly received assuming the beam and QCL of the first type signal, but the overlapping problem in the time domain as described above can be reasonably resolved compared to the case where only one signal is received simply according to priority.

[0097]

[0098] Specifically, assuming a 5G situation, in one embodiment of the present invention, UE1 may transmit PSCCH / PSSCH by controlling them so that they do not overlap with the resource region of SA-CSI-RS in the time domain while knowing the resource region designated for SA-CSI-RS transmission.

[0099] However, considering the concept of blind retransmission resource reservation of PSCCH / PSSCH as described above with reference to FIG. 3, PSCCH / PSSCH and CSI-RS are likely to overlap in the time domain. If the beam for receiving PSCCH / PSSCH and the beam for receiving CSI-RS are different, it is desirable for the UE to focus on receiving one signal, and accordingly, one signal may be deleted by puncturing and a signal with a higher priority may be received. However, in a preferred embodiment of the present invention, it is proposed to receive the second type signal by assuming that the beam is QCLed with respect to the beam of the first type signal with a higher priority as described above.

[0100]

[0101] FIG. 7 is a diagram for explaining a method for explaining the priority of a received signal according to a direct link communication situation according to one embodiment of the present invention.

[0102] First, the priority between the SA-RS and the physical control channel / physical shared channel is determined (S710). In the first situation, a type 1 signal with a higher priority can be determined as the SA-RS, and a type 2 signal with a lower priority can be determined as the physical control channel / physical shared channel.

[0103] Accordingly, since the receiving UE assumes that the reception beam of the SA-RS is QCLed even when receiving a low-priority physical control channel / physical shared channel, the reception performance of the physical control channel / physical shared channel may deteriorate to a certain degree, but since priority is given to the reception of the SA-RS, beam management can be performed more accurately.

[0104] Therefore, in one embodiment of the present invention, it is preferable that the first situation be set as a situation in which thorough beam management performance is more emphasized than throughput.

[0105] In addition, the priority between SA-RS and physical control channel / physical shared channel is determined (S710), and in the second situation, a first type signal with a higher priority can be determined as the physical control channel / physical shared channel, and a second type signal with a lower priority can be determined as the SA-RS.

[0106] Accordingly, since the receiving UE assumes that the reception beam of the physical control channel / physical shared channel is QCL when receiving the SA-RS with a low priority (S730), the reception performance of the SA-RS may deteriorate to a certain degree, but since priority is given to the reception of the physical control channel / physical shared channel, the data transmission throughput can be increased.

[0107] Therefore, in one embodiment of the present invention, it is preferable that the second situation be set as a situation in which a high processing rate is more emphasized.

[0108] The first situation / second situation as described above can be set by the network according to the situation of the direct communication link and configured through an RRC message, or alternatively, the configuration can be set to be activated according to the situation of each UE according to the preset configuration information.

[0109]

[0110] FIG. 8 is a diagram for explaining a method for explaining the priority of a received signal depending on whether a control channel / shared channel is initially transmitted or retransmitted according to one embodiment of the present invention.

[0111] As described above with respect to FIG. 5, the third time resource for transmitting SA-RS may overlap with the first time resource for initial transmission of the physical control channel / physical shared channel (the second situation in FIG. 5) and may overlap with the second time resource for retransmission (the first situation in FIG. 5).

[0112] In one embodiment of the present invention proposed in Fig. 8, a method is proposed to set priorities differently by distinguishing between cases where there is overlap with initial transmission resources and cases where there is overlap with retransmission resources.

[0113] Specifically, in the embodiment proposed in FIG. 8, in a second situation where the third time resource for SA-RS transmission overlaps with the first time resource for initial transmission of a physical control channel / physical shared channel, it is proposed to process the SA-RS by giving it a higher priority (S820). Accordingly, the receiving UE can receive the SA-RS even when receiving a physical control channel / physical shared channel with a lower priority, assuming that it is QCL with the reception beam of the SA-RS (S820), and accordingly, when decoding of the physical control channel / physical shared channel fails, reception can be attempted through retransmission.

[0114] Meanwhile, in the embodiment proposed in FIG. 8, in the first situation where the third time resource for SA-RS transmission overlaps with the second time resource for retransmission of the physical control channel / physical shared channel, it is proposed to process the physical control channel / physical shared channel by giving it a higher priority (S830). That is, it can be considered that the improvement in reception performance of the physical control channel / physical shared channel that has already been retransmitted due to decoding failure in the initial transmission may be more sensitive to communication quality. Accordingly, the receiving UE can receive the SA-RS with the assumption that it is QCL with the reception beam of the physical control channel / physical shared channel even when receiving the SA-RS with a low priority (S830).

[0115] Meanwhile, in another embodiment of the present invention, even if the third time resource for SA-RS reception overlaps with the second time resource for retransmission reception of a physical control channel / physical shared channel, if the decoding of the already received physical control channel / physical shared channel is successful, the SA-RS may be received with a higher priority. As described above with reference to FIG. 3, the resource for retransmission of a physical control channel / physical shared channel is not a resource that is retransmitted when the actual receiving UE (UE2) fails to decode, but is a concept in which resources for retransmission are reserved in a blind manner regardless of the actual decoding. Therefore, when the time resource (the third time resource) for SA-RS transmission overlaps with the time resource (the second time resource) for retransmission of a physical control channel / physical shared channel, it is possible to set priorities between signals by considering whether the actual decoding of the corresponding physical control channel / physical shared channel is successful from the perspective of the receiving UE (UE2).

[0116] FIG. 9 is a diagram for explaining a method of considering different priorities of a physical control channel / physical shared channel according to one embodiment of the present invention.

[0117] In this embodiment, it is proposed to define the priorities between signals as follows.

[0118] 1st priority: Physical control channel

[0119] 2nd Place: SA-RS

[0120] 3rd Place: Physical Sharing Channel

[0121] In general, control information has a greater impact on communication quality than data transmitted over a shared channel, and therefore, sequential priorities can be specified as described above.

[0122] As illustrated in FIG. 9, in 5G NR, it is assumed that a PSCCH (910) corresponding to a physical control channel and a PSSCH (920) corresponding to a physical shared channel are transmitted through a single slot (900) and received through the same beam. In addition, the PSCCH (910) may be transmitted subsequently to the initial symbol of the slot, and the PSSCH (920) may be transmitted subsequently after an interval (930) that takes into account the decoding time of the PSCCH (910).

[0123] According to the priority as described above in this structure, the CSI-RS (940) that overlaps in the time period in which the PSCCH (910) is transmitted can be received assuming that it is QCL with the reception beam of the PSCCH (910) due to being behind in priority. In contrast, the CSI-RS (950) that overlaps in the time period in which the PSSCH (920) is transmitted has a higher priority and can be received with priority over the PSSCH (920).

[0124] Meanwhile, in FIG. 9, it is assumed that the CSI-RS (960) is processed with a low priority when it overlaps with the interval (930) for decoding the PSCCH (910), but it is not necessary to be limited thereto, and the reception of the CSI-RS (960) may be given higher priority in the interval (930) in which there is no reception of the PSCCH (910) / PSSCH (920).

[0125] FIG. 10 is a diagram for explaining a method of dynamically indicating priority information through SCI according to one embodiment of the present invention.

[0126] In the embodiment of Fig. 10, basic priority information can also be set as follows.

[0127] 1st priority: Physical control channel

[0128] 2nd Place: SA-RS

[0129] 3rd Place: Physical Sharing Channel

[0130] However, in this embodiment, it is proposed that priority information regarding which signal among the subsequent PSSCH and CSI-RS is to be processed with priority be additionally transmitted through the SCI transmitted through the PSCCH (1030a, 1030b), and this may utilize L1-priority information transmitted through the SCI, but need not be limited thereto.

[0131] In FIG. 10, 1010 illustrates a case (1040a) in which it is instructed to give priority to processing CSI-RS through SCI, and 1020 illustrates a case (1040b) in which it is instructed to give priority to processing PSSCH through SCI.

[0132]

[0133] FIG. 11 is a diagram for explaining a process of establishing a unicast link for performing direct communication between UEs according to one embodiment of the present invention.

[0134] Specifically, 9000 of FIG. 11 illustrates a process in which UE1 and UE2 perform initial beam pairing before establishing a unicast link. Additionally, 9500 of FIG. 11 illustrates a process in which UE1 and UE2 perform initial beam pairing after establishing a unicast link.

[0135] In both procedures 9000 and 9500 of FIG. 11, UE 1, which is a Tx UE, and UE 2, which is an Rx UE, can determine a destination ID for transmitting / receiving a DCR (Direct Communication Request) message (S9010, S9020, S9510, S9520).

[0136] For the initial beam pairing performed prior to unicast link establishment, at 9000 in FIG. 13, UE 1 can repeat the process of sweeping multiple beams and transmitting within a single symbol a predetermined number of times (S9030). UE 2, which receives a signal in which multiple beams within a slot are swept in this way, can fix the reception beam within a single slot, change the reception beam on a slot-by-slot basis, determine the reception beam that best pairs with the transmission beam of UE 1, and feed back information about the Tx beam to UE 1 (S9040).

[0137] Through beam pairing like this, UE 1 can transmit a corresponding DCR message to UE 2 (S9050).

[0138] Meanwhile, for the initial beam pairing performed after the unicast link is established, beam pairing can be performed in the form of UE 1 transmitting one beam per symbol at 9500 of FIG. 11 (S9030a to S9030d). When beam management is performed through RS transmission on a symbol-by-symbol basis in this way, processing may be delayed compared to the method of transmitting multiple beams in one symbol as in 9000 of FIG. 11. However, after the unicast link is established, the beam sweeping target is narrowed through the beam configuration between UE 1 and UE 2, thereby reducing the delay.

[0139] Through beam sweeping like this, UE 2SMS can transmit a feedback signal for the Tx beam to UE 1 (S9540).

[0140] The time domain collision management scheme proposed in FIG. 5 and subsequent embodiments can generally be applied to resolve a collision situation between PSCCH / PSSCH transmission and CSI-RS resources after a unicast link is established, as in 9500 of FIG. 11.

[0141]

[0142] Figure 12 illustrates a wireless device to which the present technology can be applied.

[0143] Referring to FIG. 12, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals via various wireless access technologies (e.g., LTE, NR). Here, the first wireless device (100) and the second wireless device (200) can each correspond to the transmitting and receiving UE of FIG. 5.

[0144] A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0145] The second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may store software code including commands for performing some or all of the processes controlled by the processor (202) or for performing the descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this document. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE E-UTRA, 5G NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0146] Hereinafter, the hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed herein, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0147] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and executed by one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0148] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0149] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of this document, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of this document, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein, via one or more antennas (108, 208). In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0150]

[0151] The detailed description of the preferred embodiments of the present invention disclosed above has been provided to enable those skilled in the art to implement and practice the present invention. While the above description has been made with reference to preferred embodiments of the present invention, those skilled in the art will appreciate that various modifications and variations can be made to the present invention without departing from the scope of the present invention. For example, those skilled in the art can utilize the individual components described in the above-described embodiments in combination with each other.

[0152] Accordingly, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

[0153] The communication method through a direct communication link according to the embodiments of the present invention as described above and the user device therefor are suitable for use in a sidelink communication environment discussed in 3GPP, but can also be widely used in communication methods other than 3GPP to solve the overlapping problem in the time domain.

Claims

1. In a communication method of a second UE that performs communication through a direct communication link with a first user equipment (UE) in a mobile communication system, From the first UE, receiving a physical control channel through the direct communication link in the first time resource; Receive a physical shared channel corresponding to the above physical control channel through the direct communication link in the first time resource; and Including receiving an RS (Reference Signal) for beam management of the above direct communication link, For at least one of the above physical control channel or the above physical shared channel, a second time resource for retransmission is reserved based on control information transmitted by the above physical control channel, Receiving the above RS, Includes receiving a standalone RS without data transmission via a third time resource, In case the third time resource overlaps with the first time resource or the second time resource, the receiving beam is determined based on the priority of the standalone RS and at least one of the physical control channel or the physical shared channel. Communication method.

2. In paragraph 1, If the priority of the first type of signal among the standalone RS and one or more of the physical control channel or the physical shared channel is high, Assuming that the second beam for receiving a second type of signal among the standalone RS and at least one of the physical control channel or the physical shared channel is QCL (quasi co-located) with the first beam for receiving the first type of signal, Communication method.

3. In paragraph 2, The above first beam and the above second beam are received assuming that they are QCL of the spatial reception parameter sharing type. Communication method.

4. In paragraph 2, In the first situation, The first type signal corresponds to the standalone RS, and the second type signal corresponds to at least one of the physical control channel or the physical shared channel. Communication method.

5. In paragraph 2, In the second situation, The first type signal corresponds to at least one of the physical control channel or the physical shared channel, and the second type signal corresponds to the standalone RS. Communication method.

6. In paragraph 2, If the above third time resource overlaps with the above first time resource, The first type signal corresponds to the standalone RS, and the second type signal corresponds to at least one of the physical control channel or the physical shared channel. Communication method.

7. In paragraph 6, If the above third time resource overlaps with the above second time resource, The first type signal corresponds to at least one of the physical control channel or the physical shared channel, and the second type signal corresponds to the standalone RS. Communication method.

8. In paragraph 6, If the third time resource overlaps with the second time resource, and the second UE successfully decodes at least one of the physical control channel or the physical shared channel received in the first time resource, The first type signal corresponds to at least one of the physical control channel or the physical shared channel, and the second type signal corresponds to the standalone RS. Communication method.

9. In paragraph 6, If the third time resource overlaps with the second time resource, and the second UE fails to successfully decode at least one of the physical control channel or the physical shared channel received in the first time resource, The first type signal corresponds to at least one of the physical control channel or the physical shared channel, and the second type signal corresponds to the standalone RS. Communication method.

10. In paragraph 1, The above standalone RS has a higher priority than the physical control channel and a lower priority than the physical shared channel. Communication method.

11. In paragraph 1, Additionally comprising receiving control information indicating a priority between the physical shared channel and the standalone RS through the physical control channel. Communication method.

12. In paragraph 1, The above physical control channel includes a PSCCH (Physical Sidelink Control Channel), The above physical shared channel includes PSSCH (Physical Sidelink Shared Channel), The above standalone RS includes standalone CSI (Channel Status Information) - RS, Communication method.

13. In a mobile communication system, a second UE performs communication through a direct communication link with a first user equipment (UE). at least one processor; and At least one computer memory operably connected to said at least one processor and storing instructions that, when executed, cause said at least one processor to perform operations; The above actions are, From the first UE, receiving a physical control channel through the direct communication link in the first time resource; Receive a physical shared channel corresponding to the above physical control channel through the direct communication link in the first time resource; and Including receiving an RS (Reference Signal) for beam management of the above direct communication link, For at least one of the above physical control channel or the above physical shared channel, a second time resource for retransmission is reserved based on control information transmitted by the above physical control channel, Receiving the above RS, Includes receiving a standalone RS without data transmission via a third time resource, In case the third time resource overlaps with the first time resource or the second time resource, the receiving beam is determined based on the priority of the standalone RS and at least one of the physical control channel or the physical shared channel. User device.

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