Patent Description:
Sidelink (SL) communication is a communication scheme in which a direct link is established between User Equipments (UEs) and the UEs exchange voice and data directly with each other without intervention of an evolved Node B (eNB). SL communication is under consideration as a solution to the overhead of an eNB caused by rapidly increasing data traffic. Vehicle-to-everything (V2X) refers to a communication technology through which a vehicle exchanges information with another vehicle, a pedestrian, an object having an infrastructure (or infra) established therein, and so on. The V2X may be divided into <NUM> types, such as vehicle-to-vehicle (V2V), vehicle-to-infrastructure (V2I), vehicle-to-network (V2N), and vehicle-to-pedestrian (V2P). The V2X communication may be provided via a PC5 interface and/or Uu interface.

Document by <NPL>), and document by <NPL>), both discuss SL DRX with regards to sensing and resource selection.

Meanwhile, in sidelink communication, in the case of a UE used by a vulnerable road user (VRU) performing battery-based operation, since power saving through SL DRX is a very important technical factor for UE operation, discontinuous reception (DRX) operation for sidelink communication may be required. In this case, a transmitting UE (hereinafter referred to as a TX UE) performing a sidelink (SL) DRX operation in a mode <NUM> may need to select SL transmission resource(s) in an active time duration. For example, if the TX UE performing the SL DRX operation performs a sensing operation only in an active time related to SL DRX, the TX UE may not be able to select appropriate candidate resources based on the sensing operation. Thus, efficiency for SL communication with an RX UE may be degraded.

In accordance with the present invention, provided is a method for performing wireless communication by a first device. The method comprises: determining a selection window for selecting a sidelink (SL) resource within an active time related to SL discontinuous reception (DRX); determining a sensing window related to the selection window; performing sensing within the sensing window; selecting at least one candidate resource within the selection window based on the sensing; and extending the selection window, based on that a number of the at least one candidate resource is less than or equal to a first threshold. An interval of the extended selection window includes an inactive time related to the SL DRX. A first device and a non-transitory computer-readable storage medium are further provided.

During sidelink (SL) discontinuous reception (DRX) operation, the UE can select candidate resources within an interval extended to an inactive time duration as well as an active time duration. Through this, the UE can sufficiently secure candidate resources, and the UE can efficiently perform SL communication based on the secured candidate resources.

For example, the UE can additionally secure candidate resources within the interval extended to the inactive time duration related to the SL DRX. Through this, it is possible to avoid selecting a resource with a high possibility of collision with resources occupied by other UEs.

In the present disclosure, "A or B" may mean "only A", "only B" or "both A and B. " In other words, in the present disclosure, "A or B" may be interpreted as "A and/or B". For example, in the present disclosure, "A, B, or C" may mean "only A", "only B", "only C", or "any combination of A, B, C".

A slash (/) or comma used in the present disclosure may mean "and/or". For example, "A, B, C" may mean "A, B, or C".

In the present disclosure, "at least one of A and B" may mean "only A", "only B", or "both A and B". In addition, in the present disclosure, the expression "at least one of A or B" or "at least one of A and/or B" may be interpreted as "at least one of A and B".

In addition, in the present disclosure, "at least one of A, B, and C" may mean "only A", "only B", "only C", or "any combination of A, B, and C". In addition, "at least one of A, B, or C" or "at least one of A, B, and/or C" may mean "at least one of A, B, and C".

In addition, a parenthesis used in the present disclosure may mean "for example". Specifically, when indicated as "control information (PDCCH)", it may mean that "PDCCH" is proposed as an example of the "control information". In other words, the "control information" of the present disclosure is not limited to "PDCCH", and "PDCCH" may be proposed as an example of the "control information". In addition, when indicated as "control information (i.e., PDCCH)", it may also mean that "PDCCH" is proposed as an example of the "control information".

In the following description, 'when, if, or in case of' may be replaced with 'based on'.

A technical feature described individually in one figure in the present disclosure may be individually implemented, or may be simultaneously implemented.

In the present disclosure, a higher layer parameter may be a parameter which is configured, pre-configured or pre-defined for a UE. For example, a base station or a network may transmit the higher layer parameter to the UE. For example, the higher layer parameter may be transmitted through radio resource control (RRC) signaling or medium access control (MAC) signaling.

For terms and techniques not specifically described among terms and techniques used in the present disclosure, reference may be made to a wireless communication standard document published before the present disclosure is filed. For example, the documents in Table <NUM> below may be referred to.

Layers of a radio interface protocol between the UE and the network can be classified into a first layer (layer <NUM>, L1), a second layer (layer <NUM>, L2), and a third layer (layer <NUM>, L3) based on the lower three layers of the open system interconnection (OSI) model that is well-known in the communication system. Among them, a physical (PHY) layer belonging to the first layer provides an information transfer service by using a physical channel, and a radio resource control (RRC) layer belonging to the third layer serves to control a radio resource between the UE and the network. For this, the RRC layer exchanges an RRC message between the UE and the BS.

<FIG> shows a radio protocol architecture, based on an embodiment of the present disclosure. Specifically, (a) of <FIG> shows a radio protocol stack of a user plane for Uu communication, and (b) of <FIG> shows a radio protocol stack of a control plane for Uu communication. (c) of <FIG> shows a radio protocol stack of a user plane for SL communication, and (d) of <FIG> shows a radio protocol stack of a control plane for SL communication.

A radio resource control (RRC) layer is defined only in the control plane. The RRC layer serves to control the logical channel, the transport channel, and the physical channel in association with configuration, reconfiguration and release of RBs. The RB is a logical path provided by the first layer (i.e., the physical layer or the PHY layer) and the second layer (i.e., a MAC layer, an RLC layer, a packet data convergence protocol (PDCP) layer, and a service data adaptation protocol (SDAP) layer) for data delivery between the UE and the network.

<FIG> shows a structure of a radio frame of an NR, based on an embodiment of the present disclosure.

Table <NUM> shown below represents an example of a number of symbols per slot (Nslotsymb), a number slots per frame (Nframe,uslot), and a number of slots per subframe (Nsubframe,uslot) based on an SCS configuration (u), in a case where a normal CP is used.

The BWP may be a set of consecutive physical resource blocks (PRBs) in a given numerology. The PRB may be selected from consecutive sub-sets of common resource blocks (CRBs) for the given numerology on a given carrier.

Meanwhile, the BWP may be defined for SL. The same SL BWP may be used in transmission and reception. For example, a transmitting UE may transmit a SL channel or a SL signal on a specific BWP, and a receiving UE may receive the SL channel or the SL signal on the specific BWP. In a licensed carrier, the SL BWP may be defined separately from a Uu BWP, and the SL BWP may have configuration signaling separate from the Uu BWP. For example, the UE may receive a configuration for the SL BWP from the BS/network. For example, the UE may receive a configuration for the Uu BWP from the BS/network. The SL BWP may be (pre-)configured in a carrier with respect to an out-of-coverage NR V2X UE and an RRC_IDLE UE. For the UE in the RRC_CONNECTED mode, at least one SL BWP may be activated in the carrier.

A sidelink synchronization signal (SLSS) may include a primary sidelink synchronization signal (PSSS) and a secondary sidelink synchronization signal (SSSS), as a SL-specific sequence. The PSSS may be referred to as a sidelink primary synchronization signal (S-PSS), and the SSSS may be referred to as a sidelink secondary synchronization signal (S-SSS). For example, length-<NUM>-sequences may be used for the S-PSS, and length-<NUM> gold sequences may be used for the S-SSS. For example, a UE may use the S-PSS for initial signal detection and for synchronization acquisition. For example, the UE may use the S-PSS and the S-SSS for acquisition of detailed synchronization and for detection of a synchronization signal ID.

A physical sidelink broadcast channel (PSBCH) may be a (broadcast) channel for transmitting default (system) information which must be first known by the UE before SL signal transmission/reception. For example, the default information may be information related to SLSS, a duplex mode (DM), a time division duplex (TDD) uplink/downlink (UL/DL) configuration, information related to a resource pool, a type of an application related to the SLSS, a subframe offset, broadcast information, or the like. For example, for evaluation of PSBCH performance, in NR V2X, a payload size of the PSBCH may be <NUM> bits including <NUM>-bit cyclic redundancy check (CRC).

<FIG> shows a procedure of performing V2X or SL communication by a UE based on a transmission mode, based on an embodiment of the present disclosure. In various embodiments of the present disclosure, the transmission mode may be called a mode or a resource allocation mode. Hereinafter, for convenience of explanation, in LTE, the transmission mode may be called an LTE transmission mode. In NR, the transmission mode may be called an NR resource allocation mode.

For example, (a) of <FIG> shows a UE operation related to an LTE transmission mode <NUM> or an LTE transmission mode <NUM>. Alternatively, for example, (a) of <FIG> shows a UE operation related to an NR resource allocation mode <NUM>. For example, the LTE transmission mode <NUM> may be applied to general SL communication, and the LTE transmission mode <NUM> may be applied to V2X communication.

For example, (b) of <FIG> shows a UE operation related to an LTE transmission mode <NUM> or an LTE transmission mode <NUM>. Alternatively, for example, (b) of <FIG> shows a UE operation related to an NR resource allocation mode <NUM>.

Referring to (a) of <FIG>, in the LTE transmission mode <NUM>, the LTE transmission mode <NUM>, or the NR resource allocation mode <NUM>, a base station may schedule SL resource(s) to be used by a UE for SL transmission. For example, in step S600, a base station may transmit information related to SL resource(s) and/or information related to UL resource(s) to a first UE. For example, the UL resource(s) may include PUCCH resource(s) and/or PUSCH resource(s). For example, the UL resource(s) may be resource(s) for reporting SL HARQ feedback to the base station.

For example, the first UE may receive information related to dynamic grant (DG) resource(s) and/or information related to configured grant (CG) resource(s) from the base station. For example, the CG resource(s) may include CG type <NUM> resource(s) or CG type <NUM> resource(s). In the present disclosure, the DG resource(s) may be resource(s) configured/allocated by the base station to the first UE through a downlink control information (DCI). In the present disclosure, the CG resource(s) may be (periodic) resource(s) configured/allocated by the base station to the first UE through a DCI and/or an RRC message. For example, in the case of the CG type <NUM> resource(s), the base station may transmit an RRC message including information related to CG resource(s) to the first UE. For example, in the case of the CG type <NUM> resource(s), the base station may transmit an RRC message including information related to CG resource(s) to the first UE, and the base station may transmit a DCI related to activation or release of the CG resource(s) to the first UE.

In step S610, the first UE may transmit a PSCCH (e.g., sidelink control information (SCI) or <NUM>st-stage SCI) to a second UE based on the resource scheduling. In step S620, the first UE may transmit a PSSCH (e.g., <NUM>nd-stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second UE. In step S630, the first UE may receive a PSFCH 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 through the PSFCH. In step S640, the first UE may transmit/report HARQ feedback information to the base station through the PUCCH or the 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. For example, the HARQ feedback information reported to the base station may be information generated by the first UE based on a pre-configured rule. For example, the DCI may be a DCI for SL scheduling. For example, a format of the DCI may be a DCI format 3_0 or a DCI format 3_1. Table <NUM> shows an example of a DCI for SL scheduling.

Referring to (b) of <FIG>, in the LTE transmission mode <NUM>, the LTE transmission mode <NUM>, or the NR resource allocation mode <NUM>, a UE may determine SL transmission resource(s) within SL resource(s) configured by a base station/network or pre-configured SL resource(s). For example, the configured SL resource(s) or the pre-configured SL resource(s) may be a resource pool. For example, the UE may autonomously select or schedule resource(s) for SL transmission. For example, the UE may perform SL communication by autonomously selecting resource(s) within the configured resource pool. For example, the UE may autonomously select resource(s) within a selection window by performing a sensing procedure and a resource (re)selection procedure. For example, the sensing may be performed in a unit of subchannel(s). For example, in step S610, a first UE which has selected resource(s) from a resource pool by itself may transmit a PSCCH (e.g., sidelink control information (SCI) or <NUM>st-stage SCI) to a second UE by using the resource(s). In step S620, the first UE may transmit a PSSCH (e.g., <NUM>nd-stage SCI, MAC PDU, data, etc.) related to the PSCCH to the second UE. In step S630, the first UE may receive a PSFCH related to the PSCCH/PSSCH from the second UE. Referring to (a) or (b) of <FIG>, for example, the first UE may transmit a SCI to the second UE through the PSCCH. Alternatively, for example, the first UE may transmit two consecutive SCIs (e.g., <NUM>-stage SCI) to the second UE through the PSCCH and/or the PSSCH. In this case, the second UE may decode two consecutive SCIs (e.g., <NUM>-stage SCI) to receive the PSSCH from the first UE. In the present disclosure, a SCI transmitted through a PSCCH may be referred to as a <NUM>st SCI, a first SCI, a <NUM>st-stage SCI or a <NUM>st-stage SCI format, and a SCI transmitted through a PSSCH may be referred to as a <NUM>nd SCI, a second SCI, a <NUM>nd-stage SCI or a <NUM>nd-stage SCI format. For example, the <NUM>st-stage SCI format may include a SCI format <NUM>-A, and the <NUM>nd-stage SCI format may include a SCI format <NUM>-A and/or a SCI format <NUM>-B. Table <NUM> shows an example of the <NUM>st-stage SCI format.

Table <NUM> shows an example of the <NUM>nd-stage SCI format.

Referring to (a) or (b) of <FIG>, in step S630, the first UE may receive the PSFCH. For example, the first UE and the second UE may determine a PSFCH resource, and the second UE may transmit HARQ feedback to the first UE using the PSFCH resource. Referring to (a) of <FIG>, in step S640, the first UE may transmit SL HARQ feedback to the base station through the PUCCH and/or the PUSCH.

<FIG> shows three cast types, based on an embodiment of the present disclosure. Specifically, (a) of <FIG> shows broadcast-type SL communication, (b) of <FIG> shows unicast type-SL communication, and (c) of <FIG> shows groupcast-type SL communication. In case of the unicast-type SL communication, a UE may perform one-to-one communication with respect to another UE. In case of the groupcast-type SL transmission, the UE may perform SL communication with respect to one or more UEs in a group to which the UE belongs. In various embodiments of the present disclosure, SL groupcast communication may be replaced with SL multicast communication, SL one-to-many communication, or the like.

Tables <NUM> to <NUM> show examples of DRX.

Referring to Table <NUM>, parameters related to SL DRX may be defined like parameters related to DRX.

Tables <NUM> to <NUM> show an example of an active time for a serving cell for a DRX group if a DRX cycle is configured.

Meanwhile, in sidelink communication, in the case of a UE used by a vulnerable road user (VRU) performing battery-based operation, since power saving through SL DRX is a very important technical factor for UE operation, DRX operation for sidelink communication may be required. In this case, a TX UE performing an SL DRX operation in the mode <NUM> may need to select SL transmission resource(s) in an active time duration.

Based on an embodiment of the present disclosure, a method for performing mode <NUM> sensing while performing an SL DRX operation and an apparatus supporting the same are proposed. In the present disclosure, a "specific threshold value" may refer to a value pre-defined or pre-configured or configured by a network/higher layer. In the present disclosure, a "specific offset (value)" may be configured through RRC signaling of a higher layer. For example, "specific offset (value)" may be signaled through a MAC CE. For example, "specific offset (value)" may refer to a value signaled or configured through DCI. Hereinafter, for example, a UE operating in SL DRX may be referred to as an SL DRX UE, and a UE not operating in SL DRX may be referred to as a non-DRX UE.

Based on an embodiment of the present disclosure, in case that a DRX UE performs SL transmission to a DRX UE and a non-DRX UE, the DRX UE may perform SL transmission not only in an active time duration but also in an inactive time duration. Or, for example, in case that a DRX UE performs SL transmission to a DRX UE and a non-DRX UE, the DRX UE may perform SL transmission using only an inactive time duration.

Based on an embodiment of the present disclosure, the UE may select a selection window based on a value that is not smaller of a PDB value and an on-duration value, in order to select SL transmission resource(s) in an on-duration or an active time duration. For example, the UE may select a selection window based on a value that is not larger of a PDB value and an on-duration value, in order to select SL transmission resource(s) in an on-duration or an active time duration.

Based on an embodiment of the present disclosure, the DRX UE may select candidate resource(s) related to SL transmission only in an active time duration. For example, if the number of candidate transmission resources is greater than or equal to a specific threshold, the DRX UE may randomly select resource(s) from among the candidate resources and use the resource(s) for SL transmission.

For example, if the number of candidate resources is less than or equal to a specific threshold, the DRX UE may increase the number of candidate resources by increasing an RSRP threshold related to determining candidate resources in units of a specific threshold dB.

Based on an embodiment of the present disclosure, and which is in accordance with the invention, in case that a resource selection window is initially set in an active time duration, as described above, if the number of candidate resources is less than or equal to a specific threshold, the UE expands the resource selection window to an inactive time duration. In this case, the UE may expand the selection window interval based on a ratio of the number of insufficient candidate resources to a specific threshold related to the number of candidate resources.

For example, if the number of candidate resources is insufficient, the UE may extend the selection window only if the RSRP threshold reaches a specific threshold. Or, for example, if the number of candidate resources is insufficient, the RSRP threshold may be fixed and only the selection window interval may be extended by a specific threshold length. For example, if the number of candidate resources is insufficient, the RSRP threshold may be fixed and the selection window interval may be extended by a specific length. Or, for example, if the number of candidate resources is insufficient, the UE may alternately apply the increase in the RSRP threshold and the extension of the selection window. For example, if the number of candidate resources is insufficient, the UE may increase an RSRP threshold by dB corresponding to a specific threshold, and if the number of candidate resources is insufficient even in the next iteration, the UE may extend a selection window by a length corresponding to a specific threshold. In addition, if the number of candidate resources is insufficient even in the next iteration, the UE may again increase an RSRP threshold by dB corresponding to the specific threshold, and the above method may be repeatedly applied.

Based on an embodiment of the present disclosure, if the number of candidate resources is insufficient in the first iteration, the UE may extend a resource selection window by a length corresponding to a specific threshold, and if the number of candidate resources is insufficient in the subsequent iteration, the UE may increase an RSRP threshold by dB corresponding to a specific threshold. For example, if the number of candidate resources is insufficient in the first iteration, the UE may increase an RSRP threshold by dB corresponding to a specific threshold, and if the number of candidate resources is insufficient in the subsequent iteration, the UE may extend a resource selection window by a length corresponding to a specific threshold.

Based on an embodiment of the present disclosure, if the candidate resources are insufficient, the UE may increase an RSRP threshold or extend a resource selection window, by using a value larger than a specific threshold related to the increase in the RSRP threshold or a length corresponding to a specific threshold related to the extension of the resource selection window by a predetermined value, in order to reduce the power consumption required in the process of securing additional candidate resources. For example, the predetermined value may be pre-defined, or pre-configured of configured by a network or a higher layer.

Based on an embodiment of the present disclosure, the number of times of increasing the RSRP threshold or the number of times of extending the length of the resource selection window may be less than or equal to a specific threshold. In this case, if the RSRP threshold or the length of the resource selection window reaches a specific threshold, the DRX UE may perform random selection. For example, if the number of times of increasing the RSRP threshold or the number of times of extending the length of the resource selection window reaches a specific threshold, the UE may randomly select resource(s) from candidate resources secured up to the corresponding iteration time without increasing the RSRP threshold or extending the length of the resource selection window.

Based on an embodiment of the present disclosure, if a sensing window for selecting mode <NUM> resources by the DRX UE is configured only within an on-duration or an active time, the UE may perform random selection within the relatively earlier part of the on-duration or the active time without a separate sensing operation, and the UE may perform resource selection, based on the sensing in the relatively earlier part of the on-duration or the active time, within the relatively later part.

For example, a ratio between the length of the earlier part and the length of the later part of the on-duration may be set to a specific threshold value. For example, a ratio between the length of the earlier part and the length of the later part of the on-duration may be set to a specific value. For example, the length ratio may be configured differently according to a priority, a reliability, a latency, etc. related to SL transmission. For example, in the case of SL transmission requiring high priority or high reliability, or in the case of SL transmission requiring small PDB or low latency, the length ratio of the earlier part in which random selection is performed may be increased, and the number of retransmissions may be increased. In addition, in the case of SL transmission allowing low priority or low reliability, or in the case of SL transmission allowing large PDB or high latency, the length ratio of the later part in which sensing-based selection is performed may be increased.

Based on various embodiments of the present disclosure, in case that a DRX UE transmits to a DRX UE or a non-DRX UE in SL DRX operation, a power saving gain can be obtained by efficiently configuring the resource selection window in the active time duration and the inactive time duration.

<FIG> shows a procedure in which a transmitting UE selects an SL resource and performs SL communication with a receiving UE, based on an embodiment of the present disclosure, and which is in accordance with the invention.

Referring to <FIG>, in step S810, the transmitting UE determines a selection window for selecting an SL resource within an active time related to sidelink (SL) discontinuous reception (DRX). In step S820, the transmitting UE determines a sensing window related to the selection window. In step S830, the transmitting UE performs sensing within the sensing window and selects at least one candidate resource within the selection window based on the sensing.

In step S840, based on that the number of the at least one candidate resource is less than or equal to a first threshold, the transmitting UE extends the selection window and selects an SL resource within the extended selection window. In step S850, the transmitting UE may perform SL communication with the receiving UE based on the selected SL resource.

For example, based on that the number of the at least one candidate resource is less than or equal to a second threshold, a reference signal received power (RSRP) threshold related to the selection window may be increased.

For example, the RSRP threshold may be increased by a pre-configured number of times.

For example, the selection window may be determined based on a smaller value among a packet delay budget (PDB) related to the SL resource and an on-duration related to the SL DRX.

For example, the interval of the selection window may be extended based on the difference between the first threshold and the number of the at least one candidate resource.

Alternatively, for example, the selection window may be extended by a configured length.

For example, the selection window may be extended by a pre-configured number of times.

For example, the selection window may be determined based on a packet delay budget (PDB) related to the SL resource and an on-duration related to the SL DRX.

For example, the SL resource may be randomly selected based on that the increased RSRP threshold is equal to a third threshold.

For example, the selection window may include a first part and a second part. For example, the first part may precede the second part in time. For example, the SL resource may be randomly selected from among candidate resources related to the first part of the selection window, based on that the selection window in included in an active time. For example, based on sensing for the first part of the selection window, the SL resource may be selected from among candidate resources related to the second part of the selection window. For example, a ratio of the first part and the second part may be different based on at least one of a latency, a reliability or a priority related to the SL resource.

For example, based on that the number of the at least one candidate resource is less than or equal to a second threshold, the transmitting UE may increase a reference signal received power (RSRP) threshold related to the selection window. Thereafter, the transmitting UE may extend the selection window based on that the number of the at least one candidate resource is less than or equal to a first threshold. For example, the increase in the RSRP threshold related to the selection window and the extension of the selection window may be performed alternately.

<FIG> shows an example in which a selection window is extended to include an inactive time related to SL DRX, based on an embodiment of the present disclosure and which is in accordance with the invention.

Referring to <FIG>, if a selection window is configured within an active time duration and the number of candidate resources is equal to or less than a first threshold, the UE extends a resource selection window to an inactive time duration. In this case, for example, the UE may extend the selection window interval based on the difference between the number of candidate resources and the first threshold. Or, for example, the UE may extend the selection window by a pre-configured length. Or, for example, the UE may increase an RSRP threshold related to the selection window based on that the number of candidate resources is less than or equal to a second threshold. Thereafter, if the number of candidate resources is less than or equal to a first threshold, the UE may extend the selection window to an inactive time duration. Or, for example, the UE may extend the selection window to an inactive time duration based on that the number of candidate resources is less than or equal to a first threshold. Thereafter, if the number of candidate resources is less than or equal to a second threshold, the UE may increase an RSRP threshold related to the selection window.

Also, for example, if the selection window is configured within the active time duration, the UE may perform random selection within the earlier part (e.g., the first part) of the selection window without a separate sensing operation, the UE may perform resource selection, based on the sensing in the earlier part, within the later part (e.g., the second part) of the selection window. For example, a ratio between the length of the first part and the length of the second part may be set to a specific value. For example, a ratio between the length of the first part and the length of the second part may be configured differently based on at least one of a latency, a reliability, or a priority related to SL transmission. For example, in the case of SL transmission requiring high priority or high reliability, or in the case of SL transmission requiring small PDB or low latency, the ratio of the first part in which random selection is performed may be increased. For example, in the case of SL transmission allowing low priority or low reliability, or in the case of SL transmission allowing large PDB or high latency, the ratio of the second part in which sensing-based selection is performed may be increased.

<FIG> shows a method of extending a selection window by a first device, based on an embodiment of the present disclosure, and which is in accordance with the invention.

Referring to <FIG>, in step S <NUM>, the first device <NUM> determines a selection window for selecting an SL resource within an active time related to SL DRX. In step S <NUM>, the first device <NUM> determines a sensing window related to the selection window. In step S1030, the first device <NUM> performs sensing within a sensing window. In step S1040, the first device <NUM> selects at least one candidate resource within the selection window based on sensing. In step S <NUM>, the first device <NUM> extends the selection window based on that the number of at least one candidate resource is less than or equal to a first threshold. The interval of the extended selection window includes an inactive time related to SL DRX.

For example, the selection window may include a first part and a second part. For example, the first part may precede the second part in time. For example, the SL resource may be randomly selected from among candidate resources related to the first part of the selection window, based on that the selection window is included in an active time. For example, based on sensing for the first part of the selection window, the SL resource may be selected from among candidate resources related to the second part of the selection window. For example, the ratio between the first part and the second part may be different based on at least one of a latency, a reliability, or a priority related to the SL resource.

For example, based on that the number of the at least one candidate resource is less than or equal to a second threshold, the first device <NUM> may increase a reference signal received power (RSRP) threshold related to the selection window. Thereafter, based on that the number of the at least one candidate resource is less than or equal to a first threshold, the first device <NUM> may extend the selection window. For example, the increase in the RSRP threshold related to the selection window and the extension of the selection window may be performed alternately.

The above-described embodiment can be applied to various devices described below. For example, the processor <NUM> of the first device <NUM> may determine a selection window for selecting an SL resource within an active time related to SL DRX. In addition, for example, the processor <NUM> of the first device <NUM> may determine a sensing window related to the selection window. In addition, for example, the processor <NUM> of the first device <NUM> may perform sensing within the sensing window. In addition, for example, the processor <NUM> of the first device <NUM> may select at least one candidate resource within the selection window based on sensing. In addition, for example, the processor <NUM> of the first device <NUM> may extend the selection window based on that the number of at least one candidate resource is less than or equal to a first threshold. For example, the interval of the extended selection window may include an inactive time related to SL DRX.

Based on an embodiment of the present disclosure, a first device adapted to perform wireless communication may be provided. For example, the first device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: determine a selection window for selecting a sidelink (SL) resource within an active time related to SL discontinuous reception (DRX); determine a sensing window related to the selection window; perform sensing within the sensing window; select at least one candidate resource within the selection window based on the sensing; and extend the selection window, based on that a number of the at least one candidate resource is less than or equal to a first threshold. For example, an interval of the extended selection window may include an inactive time related to the SL DRX.

Based on an embodiment of the present disclosure, an apparatus adapted to control a first user equipment (UE) may be provided. For example, the apparatus may comprise: one or more processors; and one or more memories operably connected to the one or more processors and storing instructions. For example, the one or more processors may execute the instructions to: determine a selection window for selecting a sidelink (SL) resource within an active time related to SL discontinuous reception (DRX); determine a sensing window related to the selection window; perform sensing within the sensing window; select at least one candidate resource within the selection window based on the sensing; and extend the selection window, based on that a number of the at least one candidate resource is less than or equal to a first threshold. For example, an interval of the extended selection window may include an inactive time related to the SL DRX.

Based on an embodiment of the present disclosure, a non-transitory computer-readable storage medium storing instructions may be provided. For example, the instructions, when executed, may cause a first device to: determine a selection window for selecting a sidelink (SL) resource within an active time related to SL discontinuous reception (DRX); determine a sensing window related to the selection window; perform sensing within the sensing window; select at least one candidate resource within the selection window based on the sensing; and extend the selection window, based on that a number of the at least one candidate resource is less than or equal to a first threshold. For example, an interval of the extended selection window may include an inactive time related to the SL DRX.

<FIG> shows a method for a second device to perform SL communication with a first device based on an SL resource, based on an embodiment of the present disclosure.

Referring to <FIG>, in step S1110, the second device <NUM> may perform SL communication with the first device <NUM> based on a sidelink (SL) resource. For example, a selection window for selecting the SL resource may be determined within an active time related to SL discontinuous reception (DRX). For example, a sensing window related to the selection window may be determined. For example, sensing may be performed within the sensing window. For example, at least one candidate resource may be selected within the selection window based on the sensing. For example, the selection window may be extended based on that the number of the at least one candidate resource is less than or equal to a first threshold. For example, the interval of the extended selection window may include an inactive time related to the SL DRX.

For example, based on that the number of the at least one candidate resource is less than or equal to a second threshold, the second device <NUM> may increase a reference signal received power (RSRP) threshold related to the selection window. Thereafter, based on that the number of the at least one candidate resource is less than or equal to a first threshold, the second device <NUM> may extend the selection window. For example, the increase in the RSRP threshold related to the selection window and the extension of the selection window may be performed alternately.

The above-described embodiment can be applied to various devices described below. For example, the processor <NUM> of the second device <NUM> may control the transceiver <NUM> to perform SL communication with the first device <NUM> based on a sidelink (SL) resource.

Based on an embodiment of the present disclosure, a second device adapted to perform wireless communication may be provided. For example, the second device may comprise: one or more memories storing instructions; one or more transceivers; and one or more processors connected to the one or more memories and the one or more transceivers. For example, the one or more processors may execute the instructions to: perform SL communication with a first device based on a sidelink (SL) resource. For example, a selection window for selecting the SL resource may be determined within an active time related to SL discontinuous reception (DRX). For example, a sensing window related to the selection window may be determined. For example, sensing may be performed within the sensing window. For example, at least one candidate resource may be selected within the selection window based on the sensing. For example, the selection window may be extended based on that a number of the at least one candidate resource is less than or equal to a first threshold. For example, an interval of the extended selection window may include an inactive time related to the SL DRX.

Various embodiments of the present disclosure may be combined with each other.

<FIG> shows a communication system <NUM>, based on an embodiment of the present disclosure.

Referring to <FIG>, a communication system <NUM> to which various embodiments of the present disclosure are applied includes wireless devices, Base Stations (BSs), and a network. Herein, the wireless devices represent devices performing communication using Radio Access Technology (RAT) (e.g., <NUM> New RAT (NR)) or Long-Term Evolution (LTE)) and may be referred to as communication/radio/<NUM> devices. The wireless devices may include, without being limited to, a robot 100a, vehicles 100b-<NUM> and 100b-<NUM>, an eXtended Reality (XR) device 100c, a hand-held device 100d, a home appliance 100e, an Internet of Things (IoT) device 100f, and an Artificial Intelligence (AI) device/server <NUM>. For example, the vehicles may include a vehicle having a wireless communication function, an autonomous vehicle, and a vehicle capable of performing communication between vehicles. Herein, the vehicles may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). The XR device may include an Augmented Reality (AR)/Virtual Reality (VR)/Mixed Reality (MR) device and may be implemented in the form of a Head-Mounted Device (HMD), a Head-Up Display (HUD) mounted in a vehicle, a television, a smartphone, a computer, a wearable device, a home appliance device, a digital signage, a vehicle, a robot, etc. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), and a computer (e.g., a notebook). For example, the BSs and the network may be implemented as wireless devices and a specific wireless device 200a may operate as a BS/network node with respect to other wireless devices.

Here, wireless communication technology implemented in wireless devices 100a to 100f of the present disclosure may include Narrowband Internet of Things for low-power communication in addition to LTE, NR, and <NUM>. In this case, for example, NB-IoT technology may be an example of Low Power Wide Area Network (LPWAN) technology and may be implemented as standards such as LTE Cat NB1, and/or LTE Cat NB2, and is not limited to the name described above. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may perform communication based on LTE-M technology. In this case, as an example, the LTE-M technology may be an example of the LPWAN and may be called by various names including enhanced Machine Type Communication (eMTC), and the like. For example, the LTE-M technology may be implemented as at least any one of various standards such as <NUM>) LTE CAT <NUM>, <NUM>) LTE Cat M1, <NUM>) LTE Cat M2, <NUM>) LTE non-Bandwidth Limited (non-BL), <NUM>) LTE-MTC, <NUM>) LTE Machine Type Communication, and/or <NUM>) LTE M, and is not limited to the name described above. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100a to 100f of the present disclosure may include at least one of Bluetooth, Low Power Wide Area Network (LPWAN), and ZigBee considering the low-power communication, and is not limited to the name described above. As an example, the ZigBee technology may generate personal area networks (PAN) related to small/low-power digital communication based on various standards including IEEE <NUM>. <NUM>, and the like, and may be called by various names.

Wireless communication/connections 150a, 150b, or 150c may be established between the wireless devices 100a to 100f/BS <NUM>, or BS <NUM>/BS <NUM>. Herein, the wireless communication/connections may be established through various RATs (e.g., <NUM> NR) such as uplink/downlink communication 150a, sidelink communication 150b (or, D2D communication), or inter BS communication (e.g. relay, Integrated Access Backhaul (IAB)). The wireless devices and the BSs/the wireless devices may transmit/receive radio signals to/from each other through the wireless communication/connections 150a and 150b. For example, the wireless communication/connections 150a and 150b may transmit/receive signals through various physical channels. To this end, at least a part of various configuration information configuring processes, various signal processing processes (e.g., channel encoding/decoding, modulation/demodulation, and resource mapping/demapping), and resource allocating processes, for transmitting/receiving radio signals, may be performed based on the various proposals of the present disclosure.

<FIG> shows wireless devices, based on an embodiment of the present disclosure.

<FIG> shows a signal process circuit for a transmission signal, based on an embodiment of the present disclosure.

<FIG> shows another example of a wireless device, based on an embodiment of the present disclosure.

<FIG> shows a hand-held device, based on an embodiment of the present disclosure. The hand-held device may include a smartphone, a smartpad, a wearable device (e.g., a smartwatch or a smartglasses), or a portable computer (e.g., a notebook). The hand-held device may be referred to as a mobile station (MS), a user terminal (UT), a Mobile Subscriber Station (MSS), a Subscriber Station (SS), an Advanced Mobile Station (AMS), or a Wireless Terminal (WT).

<FIG> shows a vehicle or an autonomous vehicle, based on an embodiment of the present disclosure. The vehicle or autonomous vehicle may be implemented by a mobile robot, a car, a train, a manned/unmanned Aerial Vehicle (AV), a ship, etc. The embodiment of <FIG> may be combined with various embodiments of the present disclosure.

Claim 1:
A method for performing wireless communication by a first device, the method comprising:
determining a selection window for selecting a sidelink, SL, resource within an active time related to SL discontinuous reception, DRX;
determining a sensing window related to the selection window;
performing sensing within the sensing window;
selecting at least one candidate resource within the selection window based on the sensing; characterised by
extending the selection window, based on that a number of the at least one candidate resource is less than or equal to a first threshold,
wherein an interval of the extended selection window includes an inactive time related to the SL DRX.