WO2017176097A1 - Method for selecting, in selection period, subframe excluding subframe relating to subframe in which transmission has been performed during sensing period in wireless communication system, and terminal using same - Google Patents

Abstract

The present invention provides a vehicle-to-X (V2X) operation method performed by a V2X terminal in a wireless communication system, the method comprising: selecting, in a selection period, a subframe excluding a subframe relating to a subframe in which transmission has been performed during a sensing period; and performing a V2X communication on the basis of the selected subframe.

Description

A method for selecting a subframe in a selection section except a subframe related to a subframe in which a transmission is performed during a sensing period in a wireless communication system and a terminal using the method

The present invention relates to wireless communication, and more particularly, to a V2X transmission resource selection method performed by a terminal in a wireless communication system and a terminal using the method.

The International Telecommunication Union Radio communication sector (ITU-R) is working on the standardization of International Mobile Telecommunication (IMT) -Advanced, the next generation of mobile communication systems after the third generation. IMT-Advanced aims to support Internet Protocol (IP) -based multimedia services at data rates of 1 Gbps in stationary and slow motions and 100 Mbps in high speeds.

3rd Generation Partnership Project (3GPP) is a system standard that meets the requirements of IMT-Advanced. Long Term Evolution is based on Orthogonal Frequency Division Multiple Access (OFDMA) / Single Carrier-Frequency Division Multiple Access (SC-FDMA) transmission. LTE-Advanced (LTE-A) is being prepared. LTE-A is one of the potential candidates for IMT-Advanced.

Recently, interest in D2D (Device-to-Device) technology for direct communication between devices is increasing. In particular, D2D is drawing attention as a communication technology for a public safety network. Commercial communication networks are rapidly changing to LTE, but current public safety networks are mainly based on 2G technology in terms of cost and conflict with existing communication standards. This gap in technology and the need for improved services have led to efforts to improve public safety networks.

The above-described D2D communication can be extended and applied to signal transmission and reception between vehicles, and communication related to vehicle (VEHICLE) is specifically called V2X (VEHICLE-TO-EVERYTHING) communication. In V2X, the term 'X' may be referred to as PEDESTRIAN (COMMUNICATION BETWEEN A VEHICLE AND A DEVICE CARRIED BY AN INDIVIDUAL (e.g., HANDHELD TERMINAL CARRIED BY A PEDESTRIAN, CYCLIST, DRIVER OR PASSENGER) , VEHICLE (COMMUNICATION BETWEEN VEHICLES) (V2V), INFRASTRUCTURE / NETWORK (COMMUNICATION BETWEEN A VEHICLE AND A ROADSIDE UNIT (RSU) / NETWORK (e.g.) OR A STATIONARY UE)) (V2I / N). A device possessed by a pedestrian (or person) is named "P-UE", and a device installed in a vehicle VEHICLE (V2X communication) is named "V-UE". In the present invention, the term 'entity' may be interpreted as at least one of P-UE, V-UE, and RSU (/ NETWORK / INFRASTRUCTURE).

On the other hand, in the V2X communication, it may be a question of how and what resource to select when the P-UE tries to transmit the V2X signal. P-UE has a feature that is sensitive to battery consumption, unlike the terminal installed in the vehicle. In addition, in V2X communication, it may be important to transmit a signal periodically and not to interfere with other terminals. In view of these points, it is necessary to determine a transmission resource selection method of the P-UE.

The technical problem to be solved by the present invention is to provide a V2X transmission resource selection method performed by a terminal in a wireless communication system and a terminal using the same.

According to an embodiment of the present invention, in a V2X operation method performed by a vehicle-to-X (V2X) terminal in a wireless communication system, subframes other than subframes related to a subframe in which a transmission is performed during a sensing interval are selected. There is provided a method for selecting in a selection period and performing V2X communication based on the selected subframe.

In this case, the excluded subframe may be a subframe in the selection period.

In this case, when a subframe in which transmission is performed during the sensing period and a subframe corresponding to a specific period overlap with a subframe reserved according to a resource reservation period of the related subframe, the related subframe may be excluded.

In this case, a subframe in which transmission is performed during the sensing period is subframe k, k is a positive integer, and a subframe corresponding to the subframe k and a specific period is a subframe (k + 100 * i). i is a positive integer set by the base station, and when the subframe (k + 100 * i) and the subframe (y + P * j) overlap, subframe y is excluded from the selection, where y is positive May be an integer, P may be a resource reservation period, and j may be a positive integer.

In this case, the range of j may be determined by a positive integer value proportional to a counter value arbitrarily determined by the V2X terminal.

In this case, the counter value may be a value of 5 or more and 15 or less.

In this case, P may be 100 ms.

In this case, the sensing interval may be 1s, and the selection interval may be 100ms.

In this case, the sensing section may be a sensing window, and the selection section may be a selection window.

In this case, the sensing window may be terminal specific.

According to another embodiment of the present invention, a user equipment (UE) includes a Radio Frequency (RF) unit for transmitting and receiving a radio signal and a processor operating in conjunction with the RF unit, wherein the processor is configured to sense A terminal is provided that selects a subframe other than a subframe related to a subframe in which transmission is performed during a period, in a selection interval, and performs V2X communication based on the selected subframe.

According to the present invention, when the terminal performs the V2X communication, it is possible to efficiently reserve resources for the V2X communication. Accordingly, since the terminal according to the present invention can efficiently use the radio resources, the occupation of unnecessary radio resources is minimized, thereby maximizing the efficiency of radio communication.

1 illustrates a wireless communication system to which the present invention can be applied.

FIG. 2 is a block diagram illustrating a radio protocol architecture for a user plane.

3 is a block diagram illustrating a radio protocol structure for a control plane.

4 shows a reference structure for ProSe.

5 shows examples of arrangement of terminals and cell coverage for ProSe direct communication.

6 shows a user plane protocol stack for ProSe direct communication.

7 shows a PC 5 interface for D2D discovery.

8 is a flowchart illustrating a method of performing V2X communication based on a terminal specific sensing interval according to an embodiment of the present invention.

9 illustrates a schematic example of a terminal specific sensing window.

10 is a flowchart illustrating a method of configuring a selection window according to an embodiment of the present invention.

11 and 12 are schematic representations of [Proposed Rule # 1].

13 and 14 illustrate re-scheduled (/ selected) resource determination and (V2X MESSAGE) transmission immediately based on the rescheduled (/ selected) resource.

15 and 16 illustrate 'control (/ scheduling) information' and 'data (associated with the corresponding control (/ scheduling) information)' (in terms of 'SINGLE V2X UE') transmitted in the form of 'FDM' on the same SF. An example of the case is shown.

FIG. 17 shows an example of a case where the 'control (/ scheduling) information transmission pool' and the 'data transmission pool' are set (/ configured) in the 'FDM' form (from a system perspective).

18 is a flowchart illustrating a method of performing sensing when a number of subchannels used for V2X message transmission is plural, according to an embodiment of the present invention.

19 illustrates an example of ENERGY MEASUREMET (ie, sensing) performed with a subchannel size of data to be transmitted by a UE.

20 and 21 illustrate an example of a form of 'PARTIALLY OVERLAPPED REGION BASED SENSING' (or 'SLIDING WINDOW BASED SENSING').

FIG. 22 schematically illustrates an example in which the problem of “SFN (SYSTEM FRAME NUMBER) WRAP AROUND” occurs.

23 is a flowchart of a method for reserving a finite number of resources according to an embodiment of the present invention.

24 is a flowchart illustrating a method for reselecting a resource by a terminal according to an embodiment of the present invention.

25 is an example of a method of performing resource reservation in consideration of the above-mentioned proposal.

FIG. 26 is a flowchart of a method of excluding a subframe (in a selection window) related to a subframe in which a terminal does not perform sensing according to an embodiment of the present invention.

FIG. 27 illustrates an example of excluding a subframe (in a selection window) related to a subframe in which the terminal has not performed sensing.

28 to 30 show examples reflected in “RESOURCE EXCLUSION PROCEDURE (BASED ON PSSCH-RSRP MEASUREMENT)”.

Figure 31 shows an example of the case of increasing the (old) "DFN RANGE" value (for example, "10240" or "10176").

32 shows an example of transmitting updated system information.

33 shows an example of the hyper DFN.

34 is a flowchart of a method of performing V2X communication on an allocated V2X resource pool according to an embodiment of the present invention.

35 schematically illustrates an example in which an SLSS subframe is excluded from a V2X transmission.

FIG. 36 schematically illustrates an example in which DL and S (SPECIAL) subframes are excluded from a V2X transmission.

37 is a flowchart illustrating a method for performing reservation for a V2X transmission resource when resource reservation of a short period is set according to an embodiment of the present invention.

38 is a flowchart illustrating a method for performing sensing in a relatively short period when resource reservation of a short period is set according to an embodiment of the present invention.

39 is a block diagram illustrating a terminal in which an embodiment of the present invention is implemented.

1 illustrates a wireless communication system to which the present invention can be applied. This may also be called an Evolved-UMTS Terrestrial Radio Access Network (E-UTRAN), or Long Term Evolution (LTE) / LTE-A system.

The E-UTRAN includes a base station (BS) 20 that provides a control plane and a user plane to a user equipment (UE). The terminal 10 may be fixed or mobile and may be called by other terms such as a mobile station (MS), a user terminal (UT), a subscriber station (SS), a mobile terminal (MT), a wireless device (Wireless Device), and the like. . The base station 20 refers to a fixed station communicating with the terminal 10, and may be referred to by other terms such as an evolved-NodeB (eNB), a base transceiver system (BTS), an access point, and the like.

The base stations 20 may be connected to each other through an X2 interface. The base station 20 is connected to a Serving Gateway (S-GW) through an MME (Mobility Management Entity) and an S1-U through an Evolved Packet Core (EPC) 30, more specifically, an S1-MME through an S1 interface.

EPC 30 is composed of MME, S-GW and P-GW (Packet Data Network-Gateway). The MME has information about the access information of the terminal or the capability of the terminal, and this information is mainly used for mobility management of the terminal. S-GW is a gateway having an E-UTRAN as an endpoint, and P-GW is a gateway having a PDN as an endpoint.

Layers of the Radio Interface Protocol between the terminal and the network are based on the lower three layers of the Open System Interconnection (OSI) reference model, which is widely known in communication systems. L2 (second layer), L3 (third layer) can be divided into the physical layer belonging to the first layer of the information transfer service (Information Transfer Service) using a physical channel (Physical Channel) is provided, The RRC (Radio Resource Control) layer located in the third layer plays a role of controlling radio resources between the terminal and the network. To this end, the RRC layer exchanges an RRC message between the terminal and the base station.

FIG. 2 is a block diagram illustrating a radio protocol architecture for a user plane. 3 is a block diagram illustrating a radio protocol structure for a control plane. The user plane is a protocol stack for user data transmission, and the control plane is a protocol stack for control signal transmission.

2 and 3, a physical layer (PHY) layer provides an information transfer service to a higher layer using a physical channel. The physical layer is connected to a medium access control (MAC) layer, which is an upper layer, through a transport channel. Data is moved between the MAC layer and the physical layer through the transport channel. Transport channels are classified according to how and with what characteristics data is transmitted over the air interface.

Data moves between physical layers between physical layers, that is, between physical layers of a transmitter and a receiver. The physical channel may be modulated by an orthogonal frequency division multiplexing (OFDM) scheme and utilizes time and frequency as radio resources.

The functions of the MAC layer include mapping between logical channels and transport channels and multiplexing / demultiplexing into transport blocks provided as physical channels on transport channels of MAC service data units (SDUs) belonging to the logical channels. The MAC layer provides a service to a Radio Link Control (RLC) layer through a logical channel.

Functions of the RLC layer include concatenation, segmentation, and reassembly of RLC SDUs. In order to guarantee the various Quality of Service (QoS) required by the radio bearer (RB), the RLC layer has a transparent mode (TM), an unacknowledged mode (UM), and an acknowledged mode (Acknowledged Mode). Three modes of operation (AM). AM RLC provides error correction through an automatic repeat request (ARQ).

The RRC (Radio Resource Control) layer is defined only in the control plane. The RRC layer is responsible for the control of logical channels, transport channels, and physical channels in connection with configuration, re-configuration, and release of radio bearers. RB means a logical path provided by the first layer (PHY layer) and the second layer (MAC layer, RLC layer, PDCP layer) for data transmission between the terminal and the network.

Functions of the Packet Data Convergence Protocol (PDCP) layer in the user plane include delivery of user data, header compression, and ciphering. The functionality of the Packet Data Convergence Protocol (PDCP) layer in the control plane includes the transfer of control plane data and encryption / integrity protection.

The establishment of the RB means a process of defining characteristics of a radio protocol layer and a channel to provide a specific service, and setting each specific parameter and operation method. RB can be further divided into SRB (Signaling RB) and DRB (Data RB). The SRB is used as a path for transmitting RRC messages in the control plane, and the DRB is used as a path for transmitting user data in the user plane.

If an RRC connection is established between the RRC layer of the UE and the RRC layer of the E-UTRAN, the UE is in an RRC connected state, otherwise it is in an RRC idle state.

The downlink transmission channel for transmitting data from the network to the UE includes a BCH (Broadcast Channel) for transmitting system information and a downlink shared channel (SCH) for transmitting user traffic or control messages. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). Meanwhile, the uplink transport channel for transmitting data from the terminal to the network includes a random access channel (RACH) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or control messages.

It is located above the transport channel, and the logical channel mapped to the transport channel is a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and a multicast traffic (MTCH). Channel).

The physical channel is composed of several OFDM symbols in the time domain and several sub-carriers in the frequency domain. One sub-frame consists of a plurality of OFDM symbols in the time domain. The RB is a resource allocation unit and includes a plurality of OFDM symbols and a plurality of subcarriers. In addition, each subframe may use specific subcarriers of specific OFDM symbols (eg, the first OFDM symbol) of the corresponding subframe for the physical downlink control channel (PDCCH), that is, the L1 / L2 control channel. Transmission Time Interval (TTI) is a unit time of subframe transmission.

* 68 Now, the D2D operation will be described. In 3GPP LTE-A, a service related to D2D operation is called proximity based services (ProSe). Hereinafter, ProSe is an equivalent concept to D2D operation, and ProSe may be mixed with D2D operation. Now, ProSe is described.

ProSe has ProSe communication and ProSe direct discovery. ProSe direct communication refers to communication performed between two or more neighboring terminals. The terminals may perform communication using a user plane protocol. ProSe-enabled UE refers to a terminal that supports a procedure related to the requirements of ProSe. Unless otherwise stated, ProSe capable terminals include both public safety UEs and non-public safety UEs. The public safety terminal is a terminal that supports both a public safety-specific function and a ProSe process. A non-public safety terminal is a terminal that supports a ProSe process but does not support a function specific to public safety.

ProSe direct discovery is a process for ProSe capable terminals to discover other ProSe capable terminals that are adjacent to each other, using only the capabilities of the two ProSe capable terminals. EPC-level ProSe discovery refers to a process in which an EPC determines whether two ProSe capable terminals are in proximity and informs the two ProSe capable terminals of their proximity.

For convenience, ProSe direct communication may be referred to as D2D communication, and ProSe direct discovery may be referred to as D2D discovery.

4 shows a reference structure for ProSe.

Referring to FIG. 4, a reference structure for ProSe includes a plurality of terminals including an E-UTRAN, an EPC, a ProSe application program, a ProSe application server, and a ProSe function.

EPC represents the E-UTRAN core network structure. The EPC may include MME, S-GW, P-GW, policy and charging rules function (PCRF), home subscriber server (HSS), and the like.

ProSe application server is a user of ProSe ability to create application functions. The ProSe application server may communicate with an application program in the terminal. An application program in the terminal may use a ProSe capability for creating an application function.

The ProSe function may include at least one of the following, but is not necessarily limited thereto.

Interworking via a reference point towards the 3rd party applications

Authentication and configuration of the UE for discovery and direct communication

Enable the functionality of the EPC level ProSe discovery

ProSe related new subscriber data and handling of data storage, and also handling of ProSe identities

Security related functionality

Provide control towards the EPC for policy related functionality

Provide functionality for charging (via or outside of EPC, e.g., offline charging)

Hereinafter, a reference point and a reference interface in the reference structure for ProSe will be described.

PC1: This is a reference point between a ProSe application in a terminal and a ProSe application in a ProSe application server. This is used to define signaling requirements at the application level.

PC2: Reference point between ProSe application server and ProSe function. This is used to define the interaction between the ProSe application server and ProSe functionality. An application data update of the ProSe database of the ProSe function may be an example of the interaction.

PC3: Reference point between the terminal and the ProSe function. Used to define the interaction between the UE and the ProSe function. The setting for ProSe discovery and communication may be an example of the interaction.

PC4: Reference point between the EPC and ProSe functions. It is used to define the interaction between the EPC and ProSe functions. The interaction may exemplify when establishing a path for 1: 1 communication between terminals, or when authenticating a ProSe service for real time session management or mobility management.

PC5: Reference point for using the control / user plane for discovery and communication, relay, and 1: 1 communication between terminals.

PC6: Reference point for using features such as ProSe discovery among users belonging to different PLMNs.

SGi: can be used for application data and application level control information exchange.

<ProSe Direct Communication (D2D Communication): ProSe Direct Communication>.

ProSe direct communication is a communication mode that allows two public safety terminals to communicate directly through the PC 5 interface. This communication mode may be supported both in the case where the terminal receives service within the coverage of the E-UTRAN or in the case of leaving the coverage of the E-UTRAN.

5 shows examples of arrangement of terminals and cell coverage for ProSe direct communication.

Referring to FIG. 5 (a), UEs A and B may be located outside cell coverage. Referring to FIG. 5B, UE A may be located within cell coverage and UE B may be located outside cell coverage. Referring to FIG. 5C, UEs A and B may both be located within a single cell coverage. Referring to FIG. 5 (d), UE A may be located within the coverage of the first cell and UE B may be located within the coverage of the second cell.

ProSe direct communication may be performed between terminals in various locations as shown in FIG.

Meanwhile, the following IDs may be used for ProSe direct communication.

Source Layer-2 ID: This ID identifies the sender of the packet on the PC 5 interface.

Destination Layer-2 ID: This ID identifies the target of the packet on the PC 5 interface.

SA L1 ID: This ID is the ID in the scheduling assignment (SA) in the PC 5 interface.

6 shows a user plane protocol stack for ProSe direct communication.

Referring to FIG. 6, the PC 5 interface is composed of a PDCH, RLC, MAC, and PHY layers.

In ProSe direct communication, there may be no HARQ feedback. The MAC header may include a source layer-2 ID and a destination layer-2 ID.

<Radio Resource Allocation for ProSe Direct Communication>.

A ProSe capable terminal can use the following two modes for resource allocation for ProSe direct communication.

1.Mode 1

Mode 1 is a mode for scheduling resources for ProSe direct communication from a base station. In order to transmit data in mode 1, the UE must be in an RRC_CONNECTED state. The terminal requests the base station for transmission resources, and the base station schedules resources for scheduling allocation and data transmission. The terminal may transmit a scheduling request to the base station and may transmit a ProSe BSR (Buffer Status Report). Based on the ProSe BSR, the base station determines that the terminal has data for ProSe direct communication and needs resources for this transmission.

2. Mode 2

Mode 2 is a mode in which the terminal directly selects a resource. The terminal selects a resource for direct ProSe direct communication from a resource pool. The resource pool may be set or predetermined by the network.

On the other hand, when the terminal has a serving cell, that is, the terminal is in the RRC_CONNECTED state with the base station or located in a specific cell in the RRC_IDLE state, the terminal is considered to be within the coverage of the base station.

If the terminal is out of coverage, only mode 2 may be applied. If the terminal is in coverage, mode 1 or mode 2 may be used depending on the configuration of the base station.

If there is no other exceptional condition, the terminal may change the mode from mode 1 to mode 2 or from mode 2 to mode 1 only when the base station is configured.

<ProSe direct discovery (D2D discovery): ProSe direct discovery>

ProSe direct discovery refers to a procedure used by a ProSe capable terminal to discover other ProSe capable terminals, and may also be referred to as D2D direct discovery or D2D discovery. At this time, the E-UTRA radio signal through the PC 5 interface may be used. Information used for ProSe direct discovery is referred to as discovery information hereinafter.

7 shows a PC 5 interface for D2D discovery.

Referring to FIG. 7, the PC 5 interface includes a MAC layer, a PHY layer, and a higher layer, ProSe Protocol layer. The upper layer (ProSe Protocol) deals with the authorization of discovery information and monitoring, and the content of the discovery information is transparent to the access stratum (AS). )Do. The ProSe Protocol ensures that only valid discovery information is sent to the AS for the announcement.

The MAC layer receives discovery information from a higher layer (ProSe Protocol). The IP layer is not used for sending discovery information. The MAC layer determines the resources used to announce the discovery information received from the upper layer. The MAC layer creates a MAC protocol data unit (PDU) that carries discovery information and sends it to the physical layer. The MAC header is not added.

There are two types of resource allocation for discovery information announcements.

1. Type 1

In a manner in which resources for announcement of discovery information are allocated non-terminal-specific, the base station provides the UEs with a resource pool configuration for discovery information announcement. This configuration may be included in a system information block (SIB) and signaled in a broadcast manner. Alternatively, the configuration may be provided included in a terminal specific RRC message. Alternatively, the configuration may be broadcast signaling or terminal specific signaling of another layer besides the RRC message.

The terminal selects a resource from the indicated resource pool by itself and announces the discovery information using the selected resource. The terminal may announce the discovery information through a randomly selected resource during each discovery period.

2. Type 2

This is a method in which resources for announcement of discovery information are allocated to a terminal. The UE in the RRC_CONNECTED state may request a resource for discovery signal announcement from the base station through the RRC signal. The base station may allocate resources for discovery signal announcement with the RRC signal. The UE may be allocated a resource for monitoring the discovery signal within the configured resource pool.

For the UE in the RRC_IDLE state, the base station 1) may inform the SIB of the type 1 resource pool for discovery information announcement. ProSe direct UEs are allowed to use the Type 1 resource pool for discovery information announcement in the RRC_IDLE state. Alternatively, the base station may indicate that the base station supports ProSe direct discovery through 2) SIB, but may not provide a resource for discovery information announcement. In this case, the terminal must enter the RRC_CONNECTED state for the discovery information announcement.

For the terminal in the RRC_CONNECTED state, the base station may set whether the terminal uses a type 1 resource pool or type 2 resource for discovery information announcement through an RRC signal.

<V2X (VEHICLE-TO-X) communication>

As described above, in general, the D2D operation may have various advantages in that it transmits and receives signals between adjacent devices. For example, the D2D user equipment has a high data rate and low delay and can perform data communication. In addition, the D2D operation may distribute traffic that is driven to the base station, and may also serve to extend the coverage of the base station if the terminal performing the D2D operation serves as a relay. The above-mentioned extension of D2D communication, including the transmission and reception of signals between vehicles, is particularly referred to as V2X (VEHICLE-TO-X) communication.

Here, in one example, the term 'X' in V2X (VEHICLE-TO-X) is PEDESTRIAN (COMMUNICATION BETWEEN A VEHICLE AND A DEVICE CARRIED BY AN INDIVIDUAL (example) HANDHELD TERMINAL CARRIED BY A PEDESTRIAN, CYCLIST, DRIVER OR PASSENGER)) V2P), VEHICLE (COMMUNICATION BETWEEN VEHICLES) (V2V), INFRASTRUCTURE / NETWORK (COMMUNICATION BETWEEN A VEHICLE AND A ROADSIDE UNIT (RSU) / NETWORK (example) RSU IS A TRANSPORTATION INFRASTRUCTURE ENTITY TRANSITION AN eNB OR A STATIONARY UE)) (V2I / N). In addition, as an example, for convenience of explanation of the proposed scheme, a device (related to V2P communication) possessed by a pedestrian (or person) is called "P-UE", and a device (related to V2X communication) installed in VEHICLE is " V-UE ". Also, as an example, the term 'ENTITY' may be interpreted as P-UE and / or V-UE and / or RSU (/ NETWORK / INFRASTRUCTURE).

The V2X terminal may perform message (or channel) transmission on a predefined (or signaled) resource pool (RESOURCE POOL). In this case, the resource pool may mean a predefined resource (s) to perform the V2X operation (or to perform the V2X operation). In this case, the resource pool may be defined in terms of time-frequency, for example.

On the other hand, there may be various types of V2X transmission resource pool.

6 illustrates the type of V2X transmission resource pool.

Referring to FIG. 6A, the V2X transmission resource pool #A may be a resource pool in which only (partial) sensing is allowed. In the V2X transmission resource pool #A, the terminal should select the V2X transmission resource after performing (partial) sensing, and random selection may not be allowed. The V2X transmission resources selected by the (partial) sensing are held semi-statically at regular intervals as shown in FIG.

In order to perform V2X message transmission on the V2X transmission resource pool #A, the base station may be configured to perform (partly) a sensing operation (based on scheduling allocation decoding / energy measurement). This may be interpreted as 'random selection' of transmission resources not allowed on the V2X transmission resource pool #A, and '(partial) sensing' based transmission resource selection (only) is performed (/ allowed). Can be interpreted as The setting may be made by the base station.

Referring to FIG. 6B, the V2X transmission resource pool #B may be a resource pool in which only random selection is allowed. In the V2X transmission resource pool #B, the UE may randomly select the V2X transmission resource in the selection window without performing (partial) sensing. Here, as an example, in a resource pool in which only random selection is allowed, unlike a resource pool in which only (partial) sensing is allowed, the selected resource may be set (/ signaled) so as not to be reserved semi-statically.

The base station may be configured such that the terminal does not perform a sensing operation (based on scheduling allocation decoding / energy measurement) to perform a V2X message transmission operation on the V2X transmission resource pool #B. This may be interpreted as transmission resource 'random selection' (only) is performed (/ allowed) and / or '(partial) sensing' based transmission resource selection is not allowed on the V2X transmission resource pool #B.

Although not shown in FIG. 6, a resource pool capable of both (partial) sensing and random selection may also exist. The base station may inform that it is possible to select V2X resources in this resource pool by either of the partial sensing and the random selection (by terminal implementation).

7 illustrates a V2X transmission resource (re) selection (/ reservation) method according to a partial sensing operation.

Referring to FIG. 7, a terminal (P-UE, hereinafter identical) may be determined (/ triggered) of (re) selecting (/ reserving) a resource for V2X signal transmission (according to whether a predefined condition is satisfied). Can be. For example, assume that in subframe #m, the transmission resource (re) selection (/ reservation) has been determined or triggered. In this case, the UE may (re) select (reserve) a resource for V2X signal transmission in the subframe period from subframe # m + T1 to # m + T2. The subframe section from the subframes # m + T1 to # m + T2 is hereinafter referred to as a selection window. The selection window may consist of, for example, 100 consecutive subframes.

The UE may select at least Y subframes as candidate resources within the selection window. That is, the terminal may consider at least Y subframes as candidate resources in the selection window. The Y value may be a preset value or a value set by a network. However, how to select the Y subframes in the selection window may be a problem of the terminal implementation. That is, when the Y value is, for example, 50, the UE may select which 50 subframes from 100 subframes constituting the selection window. For example, the UE may select 50 subframes having an odd subframe number from the 100 subframes or select 50 subframes having an even subframe number. Alternatively, 50 subframes may be selected by an arbitrary rule.

Meanwhile, in order to (re) select (/ reserve) a specific subframe, for example, subframe #N (SF # N) from among the Y subframes as a V2X transmission subframe capable of transmitting a V2X signal, the UE It may be necessary to sense at least one subframe linked to or associated with subframe #N. The (whole) subframe period defined for sensing is called a sensing window, and may be composed of, for example, 1000 subframes. That is, the sensing window may consist of 1000 milliseconds (ms) or 1 second. For example, in the sensing window, the terminal may be a set of elements in the subframe # N-100 * k (where k is a range of [1, 10], and may be a value preset or set by a network). ) May sense subframes.

In FIG. 7, the k value is {1, 3, 5, 7, 10}. That is, the UE senses subframes # N-1000, # N-700, # N-500, # N-300, and # N-100 to determine whether subframe #N is being used by another V2X terminal (and / Alternatively, it is possible to estimate / determine whether there is a relatively high interference (or above a preset (/ signaled) threshold) on subframe #N) and select (finally) subframe #N accordingly. have. Since the walking terminal is more sensitive to battery consumption than the vehicle terminal, instead of sensing all subframes in the sensing window, only the partial subframes are sensed, that is, partial sensing.

For example, when performing V2V communication, an example of (A) transmission resource selection procedure (/ method) based on sensing operation and / or (B) V2V resource pool setting (/ signaling) procedure (/ method) will be described below. Can be.

(A) A transmission resource selection procedure (/ method) based on sensing operation

STEP 1: With regard to PSSCH resource (re) selection, when all PSCCH / PSSCH transmissions have the same priority, priority may be considered as a selectable resource.

STEP 2: Meanwhile, the terminal may exclude resources based on at least one of SA decoding and additional conditions.

The terminal selects a V2X transmission resource after excluding a specific resource based on scheduling assignment and additional conditions. In this case, when scheduling allocation and data associated with the same are transmitted in the same subframe, a method of excluding resources based on the DM-RS received power of the PSSCH may be supported. That is, it excludes resources indicated or reserved (reserved) by the decoded scheduling assignment and resources whose PSSCH RSRP (reference signal received power) received from data resources associated with the scheduling assignment is greater than or equal to a threshold. Specifically, the PSSCH RSRP may be defined as a linear average of power distributions of resource elements (REs) carrying DM-RSs associated with the PSSCH in the physical resource blocks (PRBs) indicated by the PSCCH. The PSSCH RSRP may be measured as a reference point for the antenna connection of the terminal. The scheduling assignment may include a 3-bit PPPP field.

The threshold may be given in the form of a function for priority information. For example, the information may be dependent on the priority information of the transport block and the priority information of the decoded scheduling assignment. The threshold may be given in units of [2 dBm] in the range of [−128 dBm] to [0 dBm]. A total of 64 thresholds can be preset.

The UE decodes the scheduling assignment in subframe # m + c within the sensing interval, and may assume that the same frequency resource is reserved (reserved) by the scheduling assignment in subframe # m + d + P * i. As described above, P may be a value fixed to 100. i may be selected in the range of [0, 1, ..., 10], which may be set or predetermined by a carrier specific network. i = 0 means no intention to reserve (reserve) frequency resources. i may be set by a 10-bit bitmap or a 4-bit field within the scheduling assignment.

In the period P * I, when the candidate semi-static resource X collides with the resource Y reserved by the scheduling allocation of another terminal and satisfies the exclusion condition, the terminal may exclude the candidate semi-static resource X. I is the value of i signaled by the scheduling assignment.

If the remaining resources after excluding the resources through the scheduling allocation decoding, sensing process, etc. is less than 20% of the total resources in the selection window, the terminal increases the threshold (for example, 3 dB), and then excludes the resources again This process may be performed until the remaining resources are greater than 20% of the total resources in the selection window. The total resources in the selection window mean resources that the terminal should consider as possible candidate resources.

Meanwhile, in the process of selecting a V2X transmission resource after excluding a specific resource, when the counter reaches a value of zero, the terminal may maintain the current resource with a probability p and reset the counter. That is, the resource may be reselected with probability 1-p.

The carrier-specific parameter p may be preset and may be set in the range of [0, 0.2, 0.4, 0.6, 0.8].

The UE measures the remaining PSSCH resources except for a specific resource and ranks based on the total received energy, and then selects a subset. The subset may be a collection of candidate resources with the lowest received energy. The size of the subset may be 20% of the total resources in the selection window.

The terminal may randomly select one resource from the subset.

When only one transport block is transmitted in one subframe, the UE may select contiguous M subchannels, and an average of energy measured in each subchannel may be an energy measurement value of each resource.

Meanwhile, when a TRANSMISSION BLOCK (TB) is transmitted in two subframes, the following resource selection may be supported.

First, one resource may be selected in which a mechanism defined for the case of TB transmitted in one subframe is used.

And, other resources may be randomly selected under the following conditions. The selected resource must not be the same subframe as the first resource and must not be a subframe excluded from the resource selection. In addition, the SCI should be able to indicate the time gap between two selected resources.

If no resource satisfies the selection condition of the second resource, the TB may be transmitted using only the first resource.

STEP 3: The UE may select a V2X transmission resource among the resources not excluded.

(B) V2V resource pool setup (/ signaling) procedure (/ method)

First, when a resource is set such that SA and data are always transmitted in the same subframe, the UE is not predicted that the mixed PSCCH is transmitted in different subframes.

If the UE is configured to always transmit SA and data in adjacent RBs of the same subframe, the subchannel having the lowest index among those selected for data transmission may be used for SA transmission.

If the UE is a pool configured to transmit SA and data in non-adjacent RBs of the same subframe, the number of SA candidate resources in the SA pool may be the same as the number of subchannels in the associated data pool. . The SA resource associated with the lowest index among those selected for data transmission may be used for SA transmission.

The terminal may make a resource selection / reselection determination at TTI m (> = n). Here, TTI m may mean the reception time of the corresponding TB.

With regard to resource reselection, the terminal should consider possible candidate resources in the [m + T1, m + T2] interval. Here, T1 may depend on the terminal implementation, and T1 <= [4]. In addition, T2 may also depend on the terminal implementation and may be 20 <= T2 <= 100. Here, the selected T2 must satisfy the latency requirement.

In addition, the sensing window may be changed as (m-a, m-b). Where a = b + 1000 and b = 1

In the case where the UE is always configured to transmit SA and data in adjacent RBs of the same subframe, the resource pool may consist of one or a plurality of subchannels in the frequency domain. Here, the subchannel may be configured as a group of adjacent RBs in the same subframe. In addition, the size of the subchannel in the resource pool may be set by the base station (e.g. eNB) or may have a preset value. Here, the candidate resource of the subchannel may mean {5, 6, 10, 15, 20, 25, 50, 75, 100}.

In the case where the UE is configured to transmit SA and data in non-contiguous RBs of the same subframe, the resource pool may consist of one or a plurality of subchannels in the frequency domain. In this case, the subchannel may be formed of a group of adjacent RBs in the same subframe. In addition, the size of the subchannel in the resource pool may be set by the base station (e.g. eNB) or may have a preset value. Here, the number of subchannels may be up to 20, and the minimum candidate size may not have a value less than four.

The UE may select an integer number of adjacent subchannels for transmission, and the UE may not decode more than [100] RBs in one subframe. In addition, the UE may not decode more than [10] PSSCHs in one subframe.

SA pools and associated data pools may overlap. In addition, SA pools and unassociated data pools may also overlap.

In the case where the UE is configured to transmit SA and data in adjacent RBs of the same subframe, the resource pool may be configured of N consecutive PRBs in the frequency domain. Here, N may be equal to (size of subchannels * number of subchannels).

The V2V pool may be defined such that the bitmap is repeatedly mapped for all subframes except the skipped SLSS subframe. Here, the length of the bitmap may mean 16, 20, or 100. Here, the bitmap may mean defining which subframes are allowed for V2V SA / data transmission and / or reception for the pool.

Meanwhile, when resource reselection is triggered, the terminal may reselect resources related to all transmissions corresponding to the TB. Here, the SA may schedule transmission corresponding to one TB. It is also possible to apply the PSSCH-RSRP measured at the TTI that occurred prior to reception of the successfully decoded associated SA. Here, the transmission number of TB may mean 1 or 2. In addition, each SA may indicate time / frequency resources of all data transmissions corresponding to the same TB.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated.

The proposed schemes below are (A) sensing when the V2X UE (S) (re) reserves (/ selects) its V2X MESSAGE transmission ( TX ) related resource (s) based on “SENSING operation”. A method of effectively defining the boundary of the time domain in which an operation is performed and / or (B) A method of efficiently supporting a retransmission ( RE-TX ) of a V2X MESSAGE (S) omitted (or interrupted) by performing a sensing operation. To present. Here, as an example, the wording of “sensing” in the present invention is an RSRP measurement (for example, on a PSSCH scheduled by a PSCCH that successfully decodes) an RSRP measurement (referred to as a predefined signal) (REFERENCE SIGNAL ( RS )) For example, an S-RSRP operation and / or an energy measurement (e.g., S-RSSI) operation for a (sub) channel may be interpreted as a predefined (/ signaled) channel (e.g., PSCCH ( PHYSICAL SIDELINK CONTROL CHANNEL)). Here, as an example, in the present invention, the wording "DURATION" (and / or "section") may be extended to "RANGE (/ WINDOW)" (and / or "range").

[Suggested Rule # 1] (per V2X UE (S)) The boundary (/ position) of the time domain (/ section) in which the sensing operation is performed indicates the form (/ characteristic) of “UE-SPECIFIC ((TIME) BOUNDARY)”. Can have Here, as an example, the boundary (/ location) of the time domain (/ section) in which a sensing operation (related to resource (re) reservation (/ selection)) of a specific V2X UE is performed is (V2X MESSAGE TX TIME) of the corresponding V2X UE. ( SF # K ) ”. When such a rule is applied, for example, the V2X UE is a resource interval from "SF # (KD) to SF # K (or SF # (K-1-D) to SF # (K-1)) (here, one example) “ D ” stands for 'SENSING DURATION', which is predefined (/ signaled) ”, at (resource) time points other than (resource) time point at which the (real) V2X MESSAGE TX operation is performed. After performing the sensing operation, the V2X MESSAGE TX related resource (s) will be (re) reserved (/ selected) in the future. Here, as another example, the V2X UE skips (/ suspends) its (V2X MESSAGE) (last) transmission on 'SF # K' (if necessary) (according to predefined rules) and uses it Sensing (/ measure) up to (or previously reserved) resource (SF # K), determining optimal rescheduling (/ selecting) resources and / or based on rescheduling (/ selecting) resources (V2X MESSAGE) transmission) can be performed immediately. Here, as another example, in the case of the V2X UE performed the sensing operation in the resource interval, "SF # (K + 1) to SF # (K + 1 + R) (or SF # K to SF # (K + Resource interval (based on sensing results) on a resource interval up to (R)) (where, for example, “ R ” stands for 'TX RESOURCE (RE) SELECTION DURATION'). You can perform a reservation (/ selection).

For the sake of understanding, the boundary of the time domain in which the sensing operation is performed (per V2X UE (S)) in the proposed rule # 1 is (shape / characteristic) of “UE-SPECIFIC (TIME) BOUNDARY”. This is described below.

8 is a flowchart illustrating a method of performing V2X communication based on a terminal specific sensing interval according to an embodiment of the present invention.

According to FIG. 8, the terminal may select a resource for performing V2X communication by performing sensing during a terminal specific sensing period (S810). Here, selecting a resource for V2X communication by performing a sensing during a specific period (that is, a terminal-specific sensing period (or a terminal-specific sensing window)) may include (A) a period in which the terminal performs sensing ( That is, the sensing window) is terminal specific, (B) the interval in which the terminal performs sensing is 1 second (that is, the interval corresponding to 1000 subframes, each subframe is 1MS interval). One second may be described based on the viewpoint that the maximum SPS PERIOD (or maximum resource reservation (possible) period) length corresponds to the length (ie [N-1000, N-1]).

(A) First, the following description will be given based on the fact that a section in which a terminal performs sensing (that is, a sensing window) is terminal specific.

As described above, the terminal may select a resource for performing V2X communication by sensing, where the sensing interval may have a different sensing interval (ie, a terminal-specific sensing interval) for each terminal. Here, having different sensing intervals for each terminal does not mean that the sensing time itself is different for each terminal, but may mean that the position of the sensing interval (that is, the sensing window) is different for each terminal.

That is, the boundary of the time domain in which the sensing operation is performed (for each V2X UE (S)) may have a form (/ characteristic) of “UE-SPECIFIC (TIME) BOUNDARY”. In other words, it means that the ENERGY MEASUREMENT WINDOW is UE-SPECIFIC (i.e., in the case of “[NA, NB]” energy sensing (/ measurement), N value is UE-SPECIFIC). It looks like this:

9 illustrates a schematic example of a terminal specific sensing window.

Referring to FIG. 9, each of the terminals 'UE 1' and 'UE 2' may have a sensing window at different times, and there may be a sensing window for each terminal at different times.

More specifically, when a request from a higher layer of the UE occurs in a specific subframe (hereinafter, subframe N), the UE determines a set of resources to be transmitted to the higher layer with respect to V2X message transmission (eg, PSSCH transmission). Can be.

Thereafter, the terminal monitors a specific sensing period (except subframes N-1000, N-999, N-998, ..., N-1) (except for subframes in which transmission by the terminal occurs). . Here, the UE monitors a specific sensing period (for example, subframes N-1000, N-999, ..., N-1) based on the subframe N determined by the upper layer of the UE itself. This means that a sensing window, which is a section in which a terminal performs monitoring, is determined by each terminal.

_Referring to the example of FIG. 9, in case of UE 1, it may be assumed that a request from an upper layer of UE 1 _occurs in _{N_UE1} . In this case, a sensing period (ie, a sensing window) in UE 1 may mean up to subframes N _{_UE1} -1000, N _{_UE1} -999, ..., N _{_UE1} -1, and the sensing window at this time is shown in FIG. Specific to UE 1 as shown in FIG. 9. Likewise, in case of UE 2, it may be assumed that a request from an upper layer of UE 2 has occurred in _{N_UE2} . In this case, a sensing period (ie, a sensing window) in UE 2 may mean up to subframes _{N_UE2} -1000, _{N_UE2} -999, ..., _{N_UE2} -1, and the sensing window at this time is shown in FIG. Specific to UE 2 as shown in FIG. 9.

Thereafter, the UE performs V2X communication based on the decoded PSCCH and the S-RSSI measured in the aforementioned subframes, that is, the subframes N-1000, N-999, N-998, ..., N-1. You can select the resources to run. Here, a specific example of selecting a resource for the terminal to perform V2X communication is as described above.

(B) The interval in which the UE performs sensing is 1 second (ie, 1000 subframe intervals), and the 1 second is the maximum SPS (SEMI-PERSISTENT SCHEDULING) PERIOD (or maximum resource reservation (possible) period) length (ie [N-1000, N-1]) will be described below.

In one example, a V2X UE is a group called 'SF # (N-A), SF # (N-A + 1),... , SF # (NB) (or SC PERIOD # (NA), SC PERIOD # (N-A + 1),…, SC PERIOD # (NB)) (A≥B (e.g., 'B' (Result may be a positive integer greater than '0' in consideration of processing time for selection)) and the sensing result obtained by monitoring the interval of ('SF # N' where resource rescheduling (/ selection) is triggered). (Or 'SC PERIOD # N') (for V2X MESSAGE TX) When used for resource (re) reservation (/ selection), “MONITORING WINDOW SIZE (ie '(AB)')” means resource (re) reservation It can also be set at the maximum of the time (/ selection) takes place (for example, interpreted as the interval of reserved resources (/ INTERVAL)). Here, in one example, the V2X UE is a 'SF # (N + C), SF # (N + C + 1), ... , SF # (N + D) (or SC PERIOD # (N + C), SC PERIOD # (N + C + 1),…, SC PERIOD # (N + D)) (D≥C (e.g., 'C' value may be a positive integer greater than '0' in consideration of the processing time related to PSCCH / PSSCH generation) and selects its own transmission resource. As a specific example, if a resource (re) reservation (/ selection) is made once every 500 milliseconds (MS), (considering '100MS', which is the length of the transmission resource (/ LATENCY REQUIREMENT)), the '( AB) 'is interpreted as' 400MS' (for example, '400MS' minus one pre-defined (/ signaled) 'SC PERIOD (100MS)' (/ LATENCY REQUIREMENT) minus' 500MS '. Also, for example, the '400MS' section may be interpreted as a section from 'SF # (N-500MS)' to 'SF # (N-100MS)'. In other words, 'SENSING DURATION' (or '(AB)') can be a function of a predefined (/ set) 'resource (re) reservation (/ selection) period' (or 'resource (re))' It can be interpreted as performing a 'SENSING operation' during a time derived from the 'reservation (/ selection) period'. In summary, for example, we will select (/ use) the same resource until 'rebooking' (/ selecting) the resource, so the sense of sensing the previous resource transfer ('rebooking (/ selecting)') However, it is not necessary to (sensing) until the time before the 'rebooking (/ selection)' occurs. Here, as an example, such a rule may be particularly useful when SA / DATA (POOL) is implemented in a 'TDM structure'.

In another example, the V2X UE (S) is linked to 'DATA (/ PSSCH) on' SF # (N + D) '(eg,' D ≧ C ') in' SF # (N + C) '. Assume a situation in which a transmission-related 'SA (/ PSCCH)' transmission is performed. Here, as an example, 'SF # N' refers to when the 'RESOURCE (RE) SELECTION' operation is performed (in accordance with a predefined rule (/ signaling)) and / or from 'SF # (NA)' to 'SF #'. (NB) '(e.g.,'A>B> 0 ') means' (SA (/ PSCCH) (' SF # (N + C) ') and / or DATA (/ PSSCH) (' SF # (N + D) ')) The sensing result referenced when performing RESOURCE (RE) SELECTION' may be assumed (/ interpreted) as an area in which (or sensing) is performed. Here, as an example, other 'TB' related 'POTENTIAL DATA (/ PSSCH)' on 'SF # (N + E)' (eg 'D <E') in 'SF # (N + D)' When performing a transfer, define (pre-signaling) the 'intent' as to whether to reuse the '(frequency) resource' (used for transmitting 'DATA (/ PSSCH)' on 'SF # (N + D)'). Channel (eg, 'SA (/ PSCCH)'('SF# (N + C)') (or 'DATA (/ PSSCH)')). Here, as an example, a ((addition)) '(EC)' value (or '(ED)' value or 'E The field in which the 'value) is transmitted may be (newly) defined. Here, as an example, the '(EC)' value ( E_ CGAP ) (or the '(ED)' value ( E_ DGAP )) (or the 'E' value ( E_GAP )) is' SA (/ PSCCH) '(' SF # (N + C) ') Scheduling from the interval (or' SA (/ PSCCH) '(' SF # (N + C) ') between the transmission point and the' NEXT TB 'related (POTENTIAL) DATA (/ PSSCH)' transmission point Interval between 'DATA (/ PSSCH)' transmission time and 'NEXT TB' related (POTENTIAL) DATA (/ PSSCH) 'transmission time) or' V2X MESSAGE GENERATION (/ TX) PERIODICITY '. Here, as an example, 'SENSING WINDOW SIZE' (eg, '(BA)') of the V2X UE may be determined (/ set) according to the below (some) rules. Here, as an example, the (maximum (/ minimum)) value related to 'E_CGAP' (or E_DGAP or E_GAP) is (from the network (or (serving) base station)) ('UE-COMMON' or 'UE-SPECIFIC') SINGLE VALUE 'or' MULTIPLE VALUE (S) '(/ signaled) or the V2X UE can be considered (/ assumed) to be the same as its (max (/ min))' MESSAGE GENERATION (/ TX) PERIODICITY '. have.

(Rule #A) 'SENSING WINDOW SIZE' means (A) 'E_CGAP' (or E_DGAP or E_GAP) related (maximum (/ min)) and / or (B) (maximum (/ min)) 'MESSAGE GENERATION (/ TX) PERIODICITY 'value. As another example, the 'SENSING WINDOW SIZE' is (A) 'E_CGAP' (or E_DGAP or E_GAP) related (maximum (/ minimum)) value and / or (B) (maximum (/ minimum)) 'MESSAGE GENERATION (/ Regardless of the value of TX) PERIODICITY ', it can be set to a predetermined value (/ signaled) in advance. Here, as an example, if such a rule is applied, the (preset (/ signaled)) (relative) setting is performed even when the V2X UE performs a (relatively) long 'V2X MESSAGE' transmission of 'MESSAGE GENERATION (/ TX) PERIODICITY'. You can also perform a sensing operation with a small value 'SENSING WINDOW SIZE' (for example, it can be interpreted as a kind of 'PARTIAL (/ LIMITED) REGION SENSING'). For example, in the rule #A, 'SENSING WINDOW SIZE' may be set to 'UE-COMMON' (or 'UE-SPECIFIC').

(Rule #B) 'SENSING WINDOW SIZE' may be considered (/ determined) as a '(V2X) SPS PERIODICITY' value that has been previously set (/ signaled). Here, as an example (when the corresponding rule is applied), if 'SPS CONFIGURATION (/ PROCESS)' having different 'SPS PERIODICITY' is set (/ signaled), 'SENSING by' SPS CONFIGURATION (/ PROCESS) ' WINDOW SIZE 'may be interpreted as something else. As another example, when a plurality of 'SPS CONFIGURATION (/ PROCESS / (operation) operation)' of different '(V2X) SPS PERIODICITY' is set (/ signaling / allowed), the maximum among the '(V2X) SPS PERIODICITY' (/ Minimum) '(COMMON) SENSING WINDOW SIZE' is determined (/ derived) and can be commonly applied to a plurality of 'SPS CONFIGURATION'. For example, in (rule #B), 'SENSING WINDOW SIZE' may be set to 'UE-SPECIFIC' (or 'UE-COMMON').

Here, the SPS period (PERIOD) may be determined as a resource reservation field in Sidelink Control Information (SCI) format 1, as shown in Table 1 below.

Resource Reservation Fields in SCI Format 1	Indicated value X	Condition
'0001', '0010', ..., '1010'	Decimal number corresponding to field	If the higher layer decides to keep resources for the transmission of the other transport block, and the value of X is 1 or more and 10 or less
'1011'	0.5	If the higher layer decides to keep resources for the transmission of the other transport block, and the value of X is 0.5
'1100'	0.2	If the higher layer decides to keep resources for the transmission of the other transport block, and the value of X is 0.2
'0000'	0	If the higher layer decides not to retain resources for the transmission of another transport block
'1101', '1110', '1111'	Reserved	-

Here, the receiving terminal (RX UE) may determine the resource reservation period of the last transmission terminal (TX UE) based on the values that can be signaled in the RESOURCE RESERVATION field on the SCI FORMAT shown in Table 1.

Here, the RX UE may determine the "resource reservation period candidate value" that the TX UE can set by multiplying the value of the resource reservation field by 100. For example, when the value of the resource reservation field is '0001', the resource reservation period value may be 100MS, and when the value of the resource reservation field is '0010', the resource reservation period value may be 200MS. Similarly, when the value of the resource reservation field is '1010', the resource reservation period value may be 1000MS.

In summary, the RX UE multiplies the value of the resource reservation field by 100 so that the “reservation period candidate value” that the TX UE can set is “20, 50, 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000MS ”, and accordingly, the maximum value of the SPS period PERIOD may have a value of 1000MS (ie, 1s).

As described above, the interval in which the terminal performs sensing (that is, the sensing window of the terminal) may have a maximum SPS (SEMI-PERSISTENT SCHEDULING) PERIOD (or maximum resource reservation (possible) period) length, and thus, the terminal The interval for performing this sensing (ie, the sensing window) may be 1000 MS (ie, 1s), which is the maximum value of the SPS period.

8 again, the terminal may perform V2X communication based on the selected resource (S820). As described above (or described later), the terminal may select a subframe within a selection window based on the sensing result performed during the terminal specific sensing interval, and the terminal determines transmission reservation resources based on the selected subframe. And V2X communication on the reserved resource. Specific examples of performing V2X communication based on the resource selected by the terminal are as described above (or described later), and thus, detailed descriptions thereof will be omitted.

On the other hand, in V2X communication, the end-to-end latency (LATENCY) must be considered. That is, when the terminal transmits the packet generated in the upper layer, not only the time for sending down the packet generated in the upper layer to the physical layer but also the time for the receiving terminal to receive the packet and then upload it to the upper layer of the receiving terminal. Should be. Accordingly, it is a matter of whether the terminal selects a resource for V2X message transmission, that is, how to configure the selection window (SELECTION WINDOW) to select the transmission resource. Hereinafter, a method of configuring the selection window will be described with reference to the drawings.

10 is a flowchart illustrating a method of configuring a selection window according to an embodiment of the present invention.

The UE may select a resource (or subframe, hereinafter, may be used to mix resources and subframes) for V2X communication within a range satisfying a latency request (LATENCY REQUIREMENT) (S1010). ). In this case, the terminal may select the resource by configuring a selection window within a range that satisfies the latency request, the V2X communication is performed in units of a plurality of subchannels, the size of the plurality of subchannels A resource for performing the V2X communication may be selected based on sensing performed in units of subchannels having a size corresponding to. The sensing area used when the sensing is performed may be an area having a size corresponding to the sizes of the plurality of subchannels. In addition, the terminal may perform sensing by using an energy measurement average value of the subchannels included in the plurality of subchannels.

In summary, the UE may select the resource by configuring a selection window within a range that satisfies the latency request, and when the V2X communication is performed in a plurality of subchannel units, a plurality of subchannel units Sensing may also be performed. Here, when the V2X communication is performed in units of a plurality of subchannels, a specific example of sensing in units of a plurality of subchannels will be described later.

Hereinafter, an example in which the terminal selects a transmission resource within a range that satisfies the latency request will be described.

The terminal may select a transmission resource (or subframe) (configuring SLECTION WINDOW) within a range that satisfies a latency request (LATENCY REQUIREMENT). Here, the UE has one set of contiguous subchannels (eg, L _subCH ) in a V2X resource pool (eg, PSSCH resource pool) included within a specific period (eg, [n + T ₁ , n + T ₂ ]). It can be assumed that it corresponds to the candidate subframe (resource) of. In this case, the selection of the information (eg, T ₁ and T ₂₎ for determining the specific section may depend on the terminal implementation. T ₁ may have a value of 4 or less, and T ₂ may have a value of 20 or more and 100 or less. In particular, the terminal selection of T ₂ should satisfy the latency requirement.

For example, 'SENSING DURATION (D)' and / or 'TX RESOURCE (RE) SELECTION DURATION (R)' are (implicitly) identical to 'V2X MESSAGE GENERATION PERIOD' (and / or '(SERVICE) LATENCY REQUIREMENT'). Assumptions (and / or 'V2X MESSAGE GENERATION PERIOD' (and / or '(SERVICE) LATENCY REQUIREMENT' and / or '(V2X MESSAGE (/ TB)) PPPP' (e.g. Specific values that are assumed (/ changed) differently according to V2X MESSAGE (/ TB) (if some) different 'PPPP' values are set (/ allowed)), and / or are predefined (/ signaled) (For example, the rule may be interpreted as 'TX RESOURCE (RE) SELECTION DURATION (R)' set to satisfy '(SERVICE) LATENCY REQUIREMENT'). Here, as an example, (in particular in the latter case) 'SENSING DURATION (D)' and 'TX RESOURCE (RE) SELECTION DURATION (R)' are (always) set to the same value or considered independent ( Or a different) value. As another example, the boundary of the time domain in which a sensing operation (related to resource (re) reservation (/ selection)) of a specific V2X UE is performed may be defined as “V2X MESSAGE GENERATION TIME” (of the corresponding V2X UE). As another example, when considering '(TX) PROCESSING TIME' (of a V2X UE), the above-described boundary criteria of a time domain in which a sensing operation is performed (regarding resource (re) reservation (/ selection)) (eg, For example, the point of time (V2X MESSAGE TX TIME, V2X MESSAGE GENERATION TIME) plus (or minus) a predetermined offset (/ signaled) in advance is based on the boundary of the time domain where the final 'sensing operation is performed. 'Can also be. In a specific example, the V2X UE is a resource interval from “SF # (KDS) to SF # (KS) (or SF # (K-1-DS) to SF # (K-1-S)) (here, for example , “D” and “ S ” respectively represent 'SENSING DURATION' (previous / signaled), '(TX) PROCESSING TIME' (of V2X UE) ”, and you are (real) V2X MESSAGE TX After the sensing operation is performed at the remaining (resource) time points other than the (resource) time point at which the operation is performed, (“SF # (K + 1) to SF # (K + 1 + R) (or SF # K to SF Resource intervals up to # (K + R)), where, for example, “R” stands for 'TX RESOURCE (RE) SELECTION DURATION', which is previously defined (/ signaled) ”in future V2X MESSAGE (Re) reserving (/ selecting) the TX-related resource (s).

Thereafter, the terminal may perform V2X communication based on the selected resource (S1020). Here, as described above, the selected resource may mean a resource determined on the basis of (SELECTION WINDOW) configured to satisfy a LATENCY REQUIREMENT (ie, a resource on a selection window that satisfies a latency request). In addition, as described above (or described later), the terminal may select a subframe within a selection window based on a sensing result performed during the terminal-specific sensing interval, and the terminal may select a transmission reservation resource based on the selected subframe. And V2X communication on the reserved resource. Specific examples of performing V2X communication based on the resource selected by the terminal are as described above (or described later), and thus, detailed descriptions thereof will be omitted.

11 and 12 are schematic representations of [Proposed Rule # 1].

11 and 12, as an example, it is assumed that the V2X MESSAGE is periodically generated (for example, '100MS') (for each V2X UE (S)). In addition, as an example, it is assumed that 'SENSING DURATION (/ TX RESOURCE (RE) SELECTION DURATION)' and 'REPETITION NUMBER related to V2X MESSAGE TX' are set to '100MS' and '1', respectively. As a further example, FIG. 11 shows the remaining (resource) time points except for (resource) time point at which the user performs a (actual) V2X MESSAGE TX operation on “resource section from SF # (K-100) to SF # K”. Reschedules its own V2X MESSAGE TX related resource (s) on “Resource section from SF # (K + 1) to SF # (K + 101)” based on the sensing result Shows the case of (/ selection). 12 shows the (resource) time points except for (resource) time point at which the user performs a (actual) V2X MESSAGE TX operation on the “resource section from SF # (K-1) to SF # (K-101)” FIG. Reschedules its own V2X MESSAGE TX related resource (s) on “Resource section from SF # (K + 1) to SF # (K + 101)” based on the sensing result Shows the case of (/ selection). For example, in FIG. 11 and FIG. 12, 'transmission of the (N + 1) th V2X MESSAGE' is performed through a reselection resource (eg, SF # (K + Z + 100)).

13 and 14 illustrate re-scheduled (/ selected) resource determination and (V2X MESSAGE) transmission immediately based on the rescheduled (/ selected) resource.

More specifically, FIG. 13 and FIG. 14 show that the V2X UE omits (V2X MESSAGE) transmission on 'SF # K' (according to a predefined rule) under the same situation as FIGS. 11 and 12, respectively. And then detect (/ measure) the resource (SF # K) that was used (or previously reserved (/ selected)) and determine the optimal rescheduled (/ selected) resource and rescheduled (/ selected) Shows the case of performing (V2X MESSAGE) transmission immediately based on the resource. Here, as an example, 'transmission of the (N + 1) th V2X MESSAGE' is performed through the reselection resource (for example, SF # (K + Z + 100)).

[Proposed rule # 2] V2X MESSAGE transmission (/ suspended) for sensing (/ measurement) of the used (or previously reserved (/ selected)) resource (in [Proposed rule # 1] above) For example, in the case of FIGS. 13 and 14, 'N-th V2X MESSAGE transmission' may be retransmitted according to the following (some) rule.

(Example # 2-1) 'Sensing (/ Measure) Result' and 'Rescheduled (/ Select)) Criteria (/ without consideration for retransmission of' Omitted / Suspended V2X MESSAGE ') After the resource reschedule (/ selection), and when retransmission of 'omitted (/ suspended) V2X MESSAGE' is performed through the rescheduled (/ selection) resource, '(SERVICE) LATENCY REQUIREMENT Can be satisfied, based on the rescheduled (/ selected) resource, the retransmission of the omitted (2) V2X MESSAGE 'can be defined (immediately). Here, as an example, on the other hand, if the '(SERVICE) LATENCY REQUIREMENT' cannot be satisfied when retransmission of the 'omitted (/ suspended) V2X MESSAGE' via the rescheduled (/ selected) resource is performed, It may be defined such that retransmission of 'omitted (/ suspended) V2X MESSAGE' is not performed based on (/ selected) resources. As a specific example, in the case of FIGS. 13 and 14, retransmission of the omitted (/ suspended) V2X MESSAGE (SF # K) is performed through the rescheduled (/ selected) resource (SF # (K + Z)). '(SERVICE) LATENCY REQUIREMENT (100MS)' can be satisfied when the V2X MESSAGE is immediately (via rescheduled (/ selected) resource (SF # (K + Z))). Retransmission of is performed.

(Example # 2-2) A V2X UE causes a resource rescheduling to take into account only 'candidate resources' whose retransmission of 'omitted (/ interrupted) V2X MESSAGE' can satisfy '(SERVICE) LATENCY REQUIREMENT'. / Optional). When such a rule is applied, for example, the V2X UE finally rescheduls (/ selects) an optimal resource that meets a predefined (rebooking (/ selection)) criterion (/ rule) among its 'candidate resources'. ) Here, as an example, not only the retransmission of the 'omitted (/ interrupted) V2X MESSAGE' through the last rescheduled (/ selected) resource, but also the transmission of 'a future (generated) V2X MESSAGE (S)' is performed. . The rule may, for example, guarantee a high probability of retransmission of 'omitted (/ interrupted) V2X MESSAGE'. In order to guarantee the above-described operation, for example, the area of 'TX RESOURCE (RE) SELECT DURATION (R)' may be reduced. This allows, for example, only nearby resources at the time of transmission (omitted) to be able to retransmit (omitted) V2X MESSAGE (S) while satisfying (SERVICE) LATENCY REQUIREMENT. This becomes selectable. In this case, as an example, the area of 'SENSING DURATION (D)' may be reduced accordingly.

(Example # 2-3) (Previous) Resource (/ POOL) for retransmission (only) of 'Omitted (/ interrupted) V2X MESSAGE' is set (/ signaled) independently (/ signaled), or V2X The UE may further select resources for retransmission of the 'omitted (/ interrupted) V2X MESSAGE' according to the below (some) rule (/ reference) previously defined (/ signaled). Here, as an example, the additionally selected corresponding resource (in the latter case) may be temporarily (or limitedly) used only for retransmission of (previously) 'omitted / stopped' V2X MESSAGE.

(Example # 2-3-1) Selecting additional (retransmission) resources, considering only the 'candidate resources' that retransmission of 'omitted (stopped) V2X MESSAGE' can satisfy '(SERVICE) LATENCY REQUIREMENT' Do it. As another example, resource rescheduling (/ selection) for transmission of future (occurring) V2X MESSAGE (S), rather than retransmission of 'omitted (/ interrupted) V2X MESSAGE', is predefined (/ signaling). It can be performed in the 'TX RESOURCE (RE) SELECTION DURATION'. Here, as an example, a resource that has been rescheduled (/ selected) for this purpose (even though it may satisfy '(SERVICE) LATENCY REQUIREMENT' when a retransmission of the 'omitted / stopped V2X MESSAGE' is performed) It can be excluded from candidate resources for retransmission of 'omitted (/ interrupted) V2X MESSAGE'. That is, for example, it is interpreted that a resource for transmission of a future (generated) V2X MESSAGE (S) has a (relatively) higher priority than a resource for retransmission of a 'omitted (/ suspended) V2X MESSAGE'. (Or, the transmission of future V2X MESSAGE (S) is interpreted as being performed through the (most) optimal resource that satisfies the predefined (rebooking (/ selection)) criteria (/ rules).) Can be.

[Proposed Rule # 3] (In [Suggested Rule # 1]) If one V2X MESSAGE is repeatedly transmitted 'Q' times, it is determined that the sensing operation is performed (regarding resource (re) reservation (/ selection)). BOUNDARY can be defined according to the below (some) criteria (/ rules). Here, as an example, the 'Q' value may be a positive integer greater than one. For convenience of explanation, hereinafter, it is assumed that (one) V2X MESSAGE is repeatedly transmitted twice (for example, SF # (N + K1), SF # (N + K1)). .

(Example # 3-1) (unless (one) V2X MESSAGE is transmitted (repeated) over multiple SF (S) and / or do independent resource allocation on each SF) first (or last) ' Repetitive transmission timing '(or' SF ') may be defined as a boundary of a time domain in which a sensing operation (related to resource (re) reservation (/ selection)) is performed. As a specific example, when the first 'repetitive transmission timing' (or 'SF') (eg, SF # (N + K1)) is designated as a boundary of a time domain in which a sensing operation is performed, the V2X UE may indicate “SF #. Resource interval from (N + K1-D) to SF # (N + K1) (or SF # (N + K1-1-D) to SF # (N + K1-1)) (here, for example, “ D ”means 'SENSING DURATION' which is defined in advance (/ signal)”, and the sensing operation is performed at the (resource) time points other than the (resource) time point at which the (real) V2X MESSAGE TX operation is performed. After executing, (re) reserving (/ selecting) V2X MESSAGE TX related resource (s) in the future. As another example, when the last 'repetitive transmission timing' (or 'SF') (eg, SF # (N + K2)) is designated as the boundary of the time domain in which the sensing operation is performed, the V2X UE may indicate “SF”. Resource interval from # (N + K2-D) to SF # (N + K2) (or SF # (N + K2-1-D) to SF # (N + K2-1)) ”, After performing the sensing operation at the remaining (resource) time points except for the (resource) time point at which the V2X MESSAGE TX operation is performed, the user may (re) reserve (/ select) the V2X MESSAGE TX related resource (s) in the future. do.

(Example # 3-2) For the purpose of sensing (/ measuring) resources that were used (or previously reserved (/ selected)), if some are omitted (/ suspended) during 'Q' repeated transmissions, the first ( Or lastly, the omitted transmission timing (or 'SF') may be defined as a boundary of a time domain in which a sensing operation (regarding resource (re) reservation (/ selection)) is performed.

Between (example # 3-3) a V2X MESSAGE a 'Q' iterations if the transmission, each transmission (or a different 'RV (REDUNDANCY VERSION)' transfer) (or initial (INITIAL) transmission and retransmission (RETRANSMISSION) The (some) parameters below may be defined (/ operated) differently (or independently). In another example, different MESSAGE 'sizes (/ types)' and / or 'transmission (/ occurrences)' and / or 'PRIORITY's (or pre-defined (/ signaling)' SECURITY information ') The following (some) parameters may be defined (or operated differently) independently (or differently) depending on whether or not is included and transmitted. As a specific example, a low (or high) priority MESSAGE-related 'SENSING DURATION value' is set long to reduce resource rebooking (/ selection) frequency, and a high (or low) priority MESSAGE-related 'SENSING DURATION' A short value can be set to make the resource rescheduling (/ selection) frequency high.

(Example # 3-3-1) 'SENSING DURATION value' (and / or 'probability value related to resource rescheduling (/ selection)' and / or 'backoff value related to resource rescheduling (/ selection)' and // Or 'MAXIMUM RESERVATION TIME' and / or 'MUTING (/ SILENCING / transmission skipping) probability (/ cycle / pattern / whether)')

As another example, the following (some) rules, 'resource (re-) reserving (/ selection) related) sensing operation' and / or 'resource rescheduling (/ selection)' can be defined to be performed.

[Suggested Rule # 4] “RANDOM MUTING (/ SILENCING / Skip / Stop)” (or “Predefined (/ signaled) probability-based MUTING (/ SILENCING / Skip / Stop))” Therefore, when a sensing operation is performed on a resource that was used (or previously reserved (/ selected)), the entire SF (S) used for (repeating) transmission of (one) V2X MESSAGE is MUTING (/ Rather than SILENCING (or rather omitting (/ stopping) 'Q' repetitive transmissions for (one) V2X MESSAGE entirely, according to predefined (/ signaling) rules (/ (hopping) pattern) You can MUTING (/ SILENCING) (or omit / stop) alternating (periodically) only some SFs (or repeated transmissions). Here, as an example, the corresponding (hopping) pattern may be '(SOURCE) UE ID' (and / or 'POOL (/ resource) cycle index (where V2X MESSAGE TX operation is performed)' and / or 'SA PERIOD index'). It may be randomized based on the input parameter (s) of. As another example, when performing “(RANDOM) MUTING (/ SILENCING / sending), the probability of '(RANDOM) MUTING (/ SILENCING / sending) / Pattern) 'may be defined differently (or independently). Here, as an example, such a rule is that the (RANDOM) MUTING (/ SILENCING / sending skipping) probability (/ cycle / pattern) 'between' RV 0 '(initial transmission) and another' RV '(retransmission). Set differently (or independently) (or '(RANDOM) MUTING (/ SILENCING / transmission skipping // stopping)' for each 'RV' (or cycle / pattern) 'differently (or independently)) It can be interpreted as As a specific example, 'RV 0' (initial transmission) may be set to be “(RANDOM) MUTING (/ SILENCING / transmitting / stopping)” with a smaller probability than other 'RV' (retransmission).

[Suggested Rule # 5] If (one) V2X MESSAGE is sent (repeated) through multiple SF (S) (or (one) V2X MESSAGE is sent 'Q' repeatedly), resource rescheduling (/ On select), instead of rescheduling (/ selecting) all SF (S) (or 'Q' repetitive transmission-related resources) at once, the predefined (/ signaling) rule (/ (hopping) pattern) Accordingly, it may be set to reschedule (/ select) only 'T' SFs (or repetitive transmission related resources) previously defined (/ signaled) at one time. Here, as an example, the value of 'T' may be set to '1'. Also, as an example, the (hopping) pattern may include '(SOURCE) UE ID' (and / or 'POOL (/ resource) cycle index (where V2X MESSAGE TX operation is performed)' and / or 'SA PERIOD index'). It may be randomized based on the input parameter (s) of. When the above rule is applied, for example, (all) resource rescheduling (/ selection) can mitigate the drastic change in the interference environment.

In another example, a channel (eg, PSCCH) in which (semi-static) (re) reservation (/ selection) of V2X MESSAGE TX related resource (s) is performed and a "sensing operation" is predefined (/ signaled). When implemented through decoding for (/ SA (SCHEDULING ASSIGNMENT))), the decoding operation of 'DATA (or PSSCH (PHYSICAL SIDELINK SHARED CHANNEL))' may be performed according to the following (some) rules.

[Proposed Rule # 6] If SA (/ PSCCH) decoding is successful in a specific period and resource reservation is set (SET (/ ON)), (A) If SA (/ PSCCH) is successfully received in the next period, It is sufficient to perform DATA (/ PSSCH) decoding according to the corresponding (received) SA (/ PSCCH), but (B) (receive) if the reception of SA (/ PSCCH) fails in the next cycle, Or reuse a number of previously defined (/ signaled) information (e.g., RA (RESOURCE ALLOCATION), MCS (MODULATION AND CODING SCHEME), RS SEQUENCE SETTING, etc.) of the most recently received SA (/ PSCCH) Can be set to attempt DATA (/ PSSCH) decoding.

[Proposed Rule # 7 - one (re) scheduling (/ optional) If you have a "maximum time" to keep the resources (for example, if there is a 'RESOURCE RESELECTION TIMER') or (PSCCH (/ SA) ( Or how to retain (re) reserved (/ selected) resources in the 'RESERVATION FIELD' (on PSSCH (/ DATA)), causing the receiving V2X UE (failed to receive SA (/ PSCCH)) to Attempts to decode DATA (/ PSSCH) based on the most recent successful reception (PSCCH (/ SA), and also avoids the resource location occupied (by another V2X UE) in 'RESOURCE (RE) ALLOCATION'. Can be set.

As another example, if there is a resource reserved (/ selected) by the V2X UE, and a better resource is found that satisfies a predefined (/ signaled) criterion (/ rule), You can also 'rebook' (/ select) a resource that you have reserved (/ selected). As a further example, instead of performing 'MUTING (/ SILENCING)' to sense (measure) the resource currently reserved by the V2X UE, another resource that has been previously set (/ signaled). Briefly moved to (/ POOL) (and / or performed a V2X MESSAGE transfer (on the moved resource (/ POOL) (which can be interpreted as 'V2X MESSAGE TX W / O RESERVATION')) You can also sense (and measure) your reserved resources and bring them back. Here, as an example, the 'time' of staying in another resource (/ POOL) may be set in advance (/ signaling). When such a rule is applied, it is possible to alleviate the omission (or interruption) of the transmission of the V2X MESSAGE by 'MUTING (/ SILENCING)' operation.

As another example, the 'boundary of time domain in which a sensing operation is performed' (relative to resource (re) reservation (/ selection)) of a specific V2X UE is selected based on a predefined (/ signal) rule. (Or REFERENCE SF) ”( SF #P ). Here, in one example, if such a rule is applied, the V2X UE is a resource interval from "SF # (P-Y1) to SF # (P + Y2) (here, for example, 'Y1 = FLOOR ((D-1)) / 2) ',' Y2 = CEILING ((D-Y1) / 2) '(or' Y1 = CEILING ((D-1) / 2) ',' Y2 = FLOOR ((D-Y1) / 2) ' )) (Or the resource section from SF # (PD) to SF # P or the resource section from SF # (P-1-D) to SF # (P-1)) ”, and then You will (re) reserve (/ select) your V2X MESSAGE TX-related resource (s) in the future. Here, “D” means 'SENSING DURATION' defined in advance (/ signal), and 'CEILING (X)' and 'FLOOR (X)' are 'functions that derive the minimum integer greater than or equal to X', respectively. , 'A function that derives the largest integer less than or equal to X'. Here, as an example, the "PIVOT SF (or REFERENCE SF)" is ('(SOURCE) UE ID' (and / or 'POOL (/ resource) period index (where the V2X MESSAGE TX operation is performed)' and / or ' Based on an input parameter (s) such as SA PERIOD index '). Further, as an example, the proposed rule may be based on the (previous) interval of the length (or pre-defined (/ signaled) length) when an initial (INITIAL) sensing operation is performed after (V2X UE) power on and / or at a previous point in time. (In Windows) only if V2X MESSAGE transmission is not performed (never).

In another example, the V2X UE (S) is linked to 'DATA (/ PSSCH) on' SF # (N + D) '(eg,' D ≧ C ') in' SF # (N + C) '. Assume a situation in which a transmission-related 'SA (/ PSCCH)' transmission is performed. Here, as an example, other 'TB' related 'POTENTIAL DATA (/ PSSCH)' on 'SF # (N + E)' (eg 'D <E') in 'SF # (N + D)' When performing a transfer, define (pre-signaling) the 'intent' as to whether to reuse the '(frequency) resource' (used for transmitting 'DATA (/ PSSCH)' on 'SF # (N + D)'). Channel (eg, 'SA (/ PSCCH)'('SF# (N + C)') (or 'DATA (/ PSSCH)')). Here, as an example, for convenience of explanation, reuse of the V2X UE # X (when performing other 'TB' related 'POTENTIAL DATA (/ PSSCH)' transmission on 'SF # (N + E)') Name '(frequency)' indicated as '/ signaled' as ' UN-BOOKING RESOURCE '. Here, as an example, when the V2X UE # Y performs a sensing operation based on 'ENERGY MEASUREMENT (and / or SA DECODING)', (currently (for example, 'SF # (N + D)') or a sensing interval Assume '(frequency) resources' indicated as 'UN-BOOKING RESOURCE' by V2X UE # X where high energy is measured (when own resource selection (/ reservation)) according to (some) rules below ( Can be processed. Because, for example, the corresponding '(frequency) resource' indicated by the V2X UE # X as 'UN-BOOKING RESOURCE' will be (for some time) in the future (including 'SF # (N + E)'). Although it is unlikely to be used, it is selected (/ reserved) by V2X UE # Y due to the high energy currently measured (eg within 'SF # (N + D)' or within the sensing interval). Because it will not be. Here, as an example, the following rules are named as 'UN-BOOKING RESOURCE' resources that the V2X UE (S) has reserved (/ selected) in a previous (resource (re) selecting (/ reserving) cycle) from a certain point in time. ) Channel (e.g. 'SA (/ PSCCH)' (or 'DATA (/ PSSCH)') that has been defined (/ signaled) in advance (to another V2X UE (S)) It can also be extended when notified. Here, as an example, the following rules are applied only when the V2X UE (S) performs a sensing operation based on 'ENERGY MEASUREMENT ONLY' or a sensing operation based on 'COMBINATION OF ENERGY MEASUREMENT AND SA DECODING'. For example, it may not be applied when performing a sensing operation based on 'SA DECODING ONLY'.

[Suggested Rule # 8] The energy measurement for '(frequency) resource' indicated by 'UN-BOOKING RESOURCE' is obtained by subtracting 'RSRP measurement' (from the energy value measured on that '(frequency) resource'). It is regarded as a value (or a value other than a preset offset value (/ signaled)), and 'RANKING' is performed for energy measured values for each resource. Here, as an example, the 'RSRP measurement' is a reference signal (eg, 'DM-' on a pre-set (/ signaled) channel (eg, 'PSBCH' (/ 'PSCCH' / 'PSSCH')). RS '). Here, as an example, when 'SA (/ PSCCH)' and 'DATA (/ PSSCH)' are 'FDM', '(frequency) resource' (or 'SA (/ PSCCH)' or 'DATA (/ PSSCH)' ) The final final 'RSRP (measurement) value' (in the actual measured 'RSRP value') is (differently depending on the separation distance (in frequency domain) between 'SA (/ PSCCH)' and 'DATA (/ PSSCH)'. The final derived (/ assumed) may be compensated for (or added to) the applied (preset (/ signaled)) 'MPR value').

[Suggested Rule # 9] 'Energy Measure Value' or 'RANKING Value' for '(Frequency) Resource' indicated by 'UN-BOOKING RESOURCE' shall be regarded as a pre-set (/ signaled) value. Can be. Here, as an example, the 'RANKING value' for the '(frequency) resource' indicated by 'UN-BOOKING RESOURCE' is the lowest probability (eg, the '(frequency) resource') is selected (/ reserved). (Or the highest probability (eg, the probability that the corresponding '(frequency) resource' is selected (/ reserved)) may be set (/ signaled). As another example, a rule may be defined such that a '(frequency) resource' indicated as 'UN-BOOKING RESOURCE' is always excluded (or (preferred) selected) at the time of resource selection (/ reservation).

On the other hand, the sensing operation of the V2X UE (S) may be performed as follows.

The following schemes suggest a (efficient) 'sensing method' for the V2X UE (S) to select 'resource resources related to V2X MESSAGE transmission ( TX )'. Here, as an example, when the 'sensing' operation is applied, different V2X UEs (at adjacent distances) select transmission resources at the same location, thereby alleviating the problem of mutual interference (when performing actual transmission). You can. Here, in one example, the wording of 'sensing' may be interpreted as (A) an energy (or power) measurement operation and / or (B) a predefined (/ signaled) channel (e.g., PSCCH (PHYSICAL SIDELINK CONTROL CHANNEL). It can be interpreted as a decoding operation for). Here, as an example, the 'energy (or power) measurement' is (A) ' RSI (RECEIVED SIGNAL STRENGTH INDICATOR) form (e.g. (the' DM-RS 'of the predefined (/ signaled) antenna port is transmitted) Average value of received powers measured in symbols) or (B) ' RSRP (REFERENCE SIGNAL RECEIVED POWER) (e.g. (of a predefined (/ signaled) antenna port)). 'The average value of the received powers measured in' RE (RESOURCE ELEMENT) 'where the' DM-RS 'is transmitted' and / or (C) 'RSSI' according to a pre-defined (/ signaled) rule (/ formula). And 'RSRP' in combination (for example, similar to ' RSRQ (REFERENCE SIGNAL RECEIVED QUALITY)').

For example, in order to alleviate the problem of (A) 'TOPOLOGY' of V2X UE (S) being changed and 'sensing' information inaccurate and / or (B) 'HALF DUPLEX' problem, the ('SINGLE V2X UE' perspective) In this case, it may be considered that 'control (/ scheduling) information' and 'data (associated with the corresponding control (/ scheduling) information)' are transmitted in the form of ' FDM (FREQUENCY DIVISION MULTIPLEXING)' on the same subframe ( SF ). have.

15 and 16 illustrate 'control (/ scheduling) information' and 'data (associated with the corresponding control (/ scheduling) information)' (in terms of 'SINGLE V2X UE') transmitted in the form of 'FDM' on the same SF. An example of the case is shown.

Here, as an example, FIG. 15 and FIG. 16 respectively indicate 'when data linked with control (/ scheduling) information is transmitted on a continuous resource RB (RESOURCE BLOCK))', 'When data linked with control (/ scheduling) information is transmitted. As another example, when considering 'LINK BUDGET' of 'control (/ scheduling) information' (in terms of 'SINGLE V2X UE'), 'control (/ scheduling) information' and '(corresponding control (/ scheduling) information) It may be considered that the 'interlocked data' is transmitted in the form of ' TDM (TIME DIVISION MULTIPLEXING)' on another SF.

FIG. 17 shows an example of a case where the 'control (/ scheduling) information transmission pool' and the 'data transmission pool' are set (/ configured) in the 'FDM' form (from a system perspective).

For example, to (A) satisfy (LATE) the 'LATENCY REQUIREMENT' of 'V2X SERVICE' and / or (B) distribute the 'control (scheduling) information' in the time domain, (from a system perspective). 'Control (scheduling) information transfer pool' and 'data transfer pool' can be set (/ configured) in the form of 'FDM'. 17 shows an example of such a case. Here, as an example, it is assumed that the 'data transmission pool' associated with a specific 'control (/ scheduling) information transmission pool' is 'TDM'.

Meanwhile, (basically) the terminal performs sensing in each (sub) channel unit, but the actual V2X message transmission may be performed in a plurality of subchannel units. If the UE has a plurality of subchannels actually used for V2X message transmission (that is, V2X message transmission is performed in units of a plurality of subchannels), it is a question of how to perform sensing. In the following description, a method of performing sensing when a plurality of subchannels are used for V2X message transmission will be described.

[Proposed Method] As an example, a rule may be defined to cause the V2X UE S to perform a sensing operation in 'resource size units' to be used for (they) 'V2X MESSAGE TX'. Here, as an example, when the corresponding rule is applied, the 'sensing resource unit size' of the V2X UE becomes equal to the 'resource size' (used by the corresponding V2X UE) for the 'V2X MESSAGE TX'. For example, when the terminal performs the energy measurement by the sensing operation, it may be a question of which resource unit / size to perform the energy measurement. At this time, in the proposed method, the unit / size of energy measurement can be a resource unit / size that the terminal uses for data transmission, for example, a subchannel size. For example, when the UE performs V2X message transmission in a specific subchannel size, energy measurement for the sensing operation may be performed in a resource unit of the specific subchannel size. Hereinafter, the proposed method will be described with reference to the drawings.

18 is a flowchart illustrating a method of performing sensing when a number of subchannels used for V2X message transmission is plural, according to an embodiment of the present invention.

According to FIG. 18, the UE selects a resource for V2X message transmission by sensing in units of subchannels having a size corresponding to the size of a subchannel used for V2X message transmission (S1810). In this case, the terminal may select the resource by configuring a selection window within a range that satisfies a latency request, and the V2X message transmission is performed in units of a plurality of subchannels, and sizes of the plurality of subchannels. A resource for performing the V2X communication may be selected based on sensing performed in units of subchannels having a size corresponding to. The sensing area used when the sensing is performed may be an area having a size corresponding to the sizes of the plurality of subchannels. In addition, the terminal may perform sensing by using an energy measurement average value of the subchannels included in the plurality of subchannels.

In summary, when the V2X communication is performed in units of a plurality of subchannels, the terminal may not only perform sensing in units of a plurality of subchannels, but also configure a selection window within a range that satisfies the latency request. The resource may be selected. Here, an example of selecting the resource by configuring a selection window within a range that satisfies the latency request is as described above.

Hereinafter, when V2X message transmission is performed in units of a plurality of subchannels, an example in which the terminal performs sensing in units of a plurality of subchannels will be described.

The terminal may perform sensing in units of subchannels having a size corresponding to the size of a subchannel used for V2X message transmission, and the terminal may select a resource for V2X message transmission based on the sensing result. In other words, the sensing (eg, ENERGY MEASUREMET) may be performed with a subchannel size of data to be transmitted by the terminal.

When sensing (eg, ENERGY MEASUREMET) is performed on the subchannel size of data to be transmitted by the UE, a linear average value of the subchannels may be used. More specifically, for the candidate single subframe resource R _{x, y} remaining in set S _A (which is a collection of all candidate single subframe resources), the sensing region (eg, the metric E _{x, y} ) is subchannels x + k It can be defined as the linear average of the S-RSSI measured at. Here, K = 0, ..., L _subCH -1 can be defined as, L _subCH may mean the number of sub-channels required when the actual packet is sent. For convenience of understanding, the present disclosure may be described as follows using the drawings.

19 illustrates an example of ENERGY MEASUREMET (ie, sensing) performed with a subchannel size of data to be transmitted by a UE. In FIG. 19, it is assumed that the subchannel size of the V2X message (eg, V2X data) that the terminal intends to transmit is 2 (that is, L _subCH = 2).

In the example of FIG. 19, ENERGY MEASUREMET may be performed in units of two subchannels corresponding to the subchannel size of data transmitted by the terminal. For example, the terminal may first determine a sensing value for the sensing region # 1 by using an average of energy sensing values in the sensing region # 1, that is, the subchannel # 1 and the subchannel # 2. In addition, the terminal may determine the sensing value for the sensing region # 2 by using the average of the energy sensing values in the sensing region # 2, that is, the subchannel # 2 and the subchannel # 3. Similarly, the terminal may determine the sensing value for the sensing region # 3 by using the average of the energy sensing values in the sensing region # 3, that is, the subchannel # 3 and the subchannel # 4.

In the example of FIG. 19, although it is assumed that two subchannel sizes of data to be transmitted by the terminal are two, the subchannel size of data to be transmitted by the terminal may have three or more values. Although not separately illustrated, if the subchannel size of the data to be transmitted by the UE is three, the UE determines a sensing value for the sensing area by using an average of energy sensing values in the subchannels # 1 to # 3. It may be.

Referring back to FIG. 18, the terminal may transmit a V2X message based on the selected resource (S1820). As described above (or described later), the terminal may select a subframe within a selection window based on the sensing result performed during the terminal specific sensing interval, and the terminal determines transmission reservation resources based on the selected subframe. And V2X communication on the reserved resource. Specific examples of performing V2X communication based on the resource selected by the terminal are as described above (or described later), and thus, detailed descriptions thereof will be omitted.

20 and 21 illustrate an example of a form of 'PARTIALLY OVERLAPPED REGION BASED SENSING' (or 'SLIDING WINDOW BASED SENSING').

In one example, the sensing operation is in the form of (A) 'NON-OVERLAPPED REGION BASED SENSING' (see FIG. 20) and / or (B) 'PARTIALLY OVERLAPPED REGION BASED SENSING' (or 'SLIDING WINDOW BASED SENSING') (see FIG. 21). ) Can be implemented. Here, as an example, when the electronic rule '(A)' is applied, the regions where the sensing operation is performed (continuously) do not overlap each other (for example, '(sensing region # 1)', ' (Sensing area # 2) 'and' (sensing area # 3) 'do not overlap each other). When the latter rule ('(B)') is applied, for example, the 'rate' (or 'volume amount // size') in which the areas in which the sensing operation is performed (continuously) are preset (/ signaled) in advance. (For example, '(sensing area # 1) and (sensing area # 2)', '(sensing area # 2) and (sensing area # 3)', '(sensing area)' on FIG. 21). 'Area' (3) and 'sensing area # 4', '(sensing area # 4) and (sensing area # 5)' are defined in advance (/ signaling), respectively (or 'amount of resources (/ size)'). You can see that they overlap each other by '). In one example, the electronic rule '(A)' may lower the 'complexity of performing the sensing operation' of the V2X UE, as compared to the latter rule ('(B)'). In other words, as an example, the total number of sensing required for the same sized resource pool may be less than the former rule '(A)' compared to the latter rule ('(B)'). On the other hand, in one example, the latter rule ('(B)') is more than the former rule ('(A)') (although there may be more 'total number of sensings' required in the same sized resource pool). MESSAGE TX 'related' available resource candidate locations' can be relatively (or closely) searched (/ selected).

In another example, after causing the V2X UE (S) to perform a sensing operation (priority) with a preset (/ signaled) 'resource unit (/ size)' (eg, '1RB') , '(Weighted) mean' (or 'SUM') (or multiple sensing (/ measures) of multiple sensing (/ measurement) values corresponding to 'resource size (/ unit)' to be used for 'V2X MESSAGE TX' The maximum value (or minimum value or median value) may be regarded as a representative sensing value for each resource size (/ unit) (to be used for V2X MESSAGE TX).

In another example, a V2X UE (S) uses a plurality of resources of discontinuous location on a frequency (resource) region to transmit (V2X) channel / signal (e.g., MULTI- When performing CLUSTER TX (or 'DVRB TX'), the previously set (/ signaled) 'sensing resource unit unit (/ size)' (for example, 'K''RB' (or ' RBG (RESOURCE BLOCK GROUP) ') (' NON-OVERLAPPED REGION BASED SENSING 'or' PARTIALLY OVERLAPPED REGION BASED SENSING '(/' SLIDING WINDOW BASED SENSING ')) It is possible to select (finally) its own 'V2X MESSAGE TX' related resources (among the resources of the (energy) measurement that are smaller (or larger) than the preset (/ signaled) threshold).

In another example, when the V2X UE (S) transmits' (SINGLE) V2X TB (/ MESSAGE) ', repeated transmission of' K times' (for example, 'K' values are 'initial transmission' and ' Assume a situation in which the number of "retransmissions" is included (all). Here, as an example, for convenience of explanation, it is assumed that the value 'K' is '4'. Here, as an example, 'SA (/ PSCCH)' transmission is performed in 'SF # (N + C)', and coordinated ('4' times) 'DATA (/ PSSCH)' transmissions are respectively 'SF # (N' + D) ',' SF # (N + D + K1) ',' SF # (N + D + K2) ',' SF # (N + D + K3) '(for example,' C ≤ D ',' 0 <K1 <K2 <K3 '). Here, as an example, 'time (A)' K times' or (B) '(K-1)' times of repetitive transmission on 'SA (/ PSCCH)' ('SF # (N + C)') A field may be defined to indicate 'resource locations', and the following (some) rules may be applied. Here, for example, in the case of the latter ('(B)'), the corresponding field is' time resource location 'related to' the remaining ('(K-1)') except 'initial (/ first) transmission' And / or 'initial (/ first) transmission' is performed (always) on the same time resource (location) as 'SA (/ PSCCH)' ('SF # (N + C)'). And / or the 'time resource location' associated with the 'initial (/ first) transmission' is defined as the 'SA (/ PSCCH)' ('SF # (N + C)') transmission time and the 'initial' It can be interpreted that the signal is signaled to the (other) field indicating the interval between the (first) transmission's time points.

(Example #A) 'Time Resource Location' related to 'Initial (/ First) Transmission' means the 'SA (/ PSCCH)'('SF# (N + C)') transmission time and the 'Initial ( 'First) Transmit' signaled to (another) ' FIELD # F ' indicating the interval between ('SF # (N + D)') and 'transmissions (of' (K-1) ')' Related 'time resource locations' (e.g. 'SF # (N + D + K1)', 'SF # (N + D + K2)', 'SF # (N + D + K3)') The maximum interval ( MAX_GAP) between the 'first transmission'('SF# (N + D)') and the 'Kth transmission'('SF# (N + D + K3)') It can be signaled with (new) ' FIELD # S ' of the same size (/ size). Here, as an example, 'FIELD # S' may be implemented in the form of 'bitmap'. Here, as an example, the 'bitmap' related to 'FIELD # S' refers to the initial (/ first) (DATA (/ PSSCH)) transmission '(' SF # (N + D) ') as a reference point (/ starting point). Can be applied. Here, as an example, when the 'MAX_GAP' value is set (/ signaling) to '10', if 'FIELD # S' is signaled (set / set) to '0100100100', 'second transmission', 'third transmission', The 'fourth transfer' is performed on 'SF # (N + D + 2)', 'SF # (N + D + 5)' and 'SF # (N + D + 8)', respectively. In another example, repeated transmissions of 'K times' (eg, 'SF # (N + D)', 'SF # (N + D + K1)', 'SF # (N + D + K2)'',' SF # (N + D + K3) ') related' time resource locations' is the pre-set (/ signaled) 'SA (/ PSCCH)'('SF# (N + C)') transmission point and it may also be signaled to 'K-th transmission' ( 'SF # (N + D + K3)') 'FIELD # Q' ( new) of the maximum distance the same size as (MAX_ TVAL) (/ size) between the point in time. Here, as an example, 'FIELD # Q' may be implemented in the form of 'bitmap'. Here, as an example, the 'bitmap' related to 'FIELD # Q' may be applied as a reference (/ starting point) based on a time point of 'SA (/ PSCCH)'('SF# (N + C)'). Here, as an example, when the 'MAX_TVAL' value is set (/ signaled) to '10', if 'FIELD # Q' is signaled (/ set) to '1100100100', 'first transmission', 'second transmission', '3rd transmission' and '4th transmission' are 'SF # (N + C + 1)', 'SF # (N + C + 2)', 'SF # (N + C + 5)', 'SF # (N + C + 8) '. In this example, if 'FIELD # F' is defined on 'SA (/ PSCCH)'('SF# (N + C)'), the value of 'FIELD # F' may be set to '1'. As another example, V2X communication-related 'CONGESTION (/ LOAD / MEASUREMENT) CONTROL results' can be a' pattern (shape / form) that 'FIELD # S' (or 'FIELD # Q' (or 'FIELD # F')) can have. Number) '(or' (max (/ min)) value (/ length) ') and / or' (max (/ min)) number of bits that can be set to '1' (on bitmap) ', etc. There may be limitations. Here, as an example, the (limitation) information is determined by the V2X UE (S) by reporting the 'CONGESTION (/ LOAD / MEASUREMENT)' situation (according to a predefined rule (/ signaling)) or ( Based on the 'CONGESTION (/ LOAD / MEASUREMENT)' information reported or measured by the V2X UE (S), the (serving) base station may set (/ signal) the UE. Here, as an example, there is a limit on the '(max (/ min)) value (/ length)' that 'MAX_GAP' (or 'MAX_TVAL') may have as 'CONGESTION (/ LOAD / MEASUREMENT) CONTROL result' related to V2X communication. It can happen (as well).

(Example #B) Repetitive transmissions of 'K' (eg 'SF # (N + D)', 'SF # (N + D + K1)', 'SF # (N + D + K2) ',' SF # (N + D + K3) ') related' time resource locations' is defined as' K 'defined on' SA (/ PSCCH) '(' SF # (N + C) ') FIELD # F '(' (example # A) ') (e.g.,' (X th) FIELD # F 'means' SA (/ PSCCH)'('SF# (N + C)') and Signaled to an interval (on the time domain) between the X th transmission 'time points.

(Example #C) (under circumstances where the (some) rules above (eg, (example #A), (example #B)) apply) ('K times'(eg,' SF # (N + D) ',' SF # (N + D + K1) ',' SF # (N + D + K2) ',' SF # (N + D + K3) '))' DATA (/ PSSCH) ' If (SA) / SA (/ PSCCH) transmission is performed per transmission, the following (some) rules may apply. Here, as an example, the following (some) rules may be limitedly applied only when '(DATA / (PSSCH)) FREQUENCY HOPPING' is performed.

(Example # 1) 'SF PATTERN' information on 'SA (/ PSCCH)' ('SF # (N + C)') related to 'initial (/ first) transmission' ('SF # (N + D)') / Field) and / or 'frequency resource (location)' information (/ field) and / or some of the 'MCS' information (/ field) are related to 'transmission of the rest (of' (K-1) ') The same may be transmitted on (/ PSCCH) '. Here, as an example, for the purpose of this division, when one 'TB' is transmitted in several SF (S), the number of times to 'SA (/ PSCCH)' scheduling (DATA / (PSSCH)) transmission on each SF ((DATA / (PSSCH)) transmission) 'COUNTER information' (or 'DATA (/ PSCCH) transmission' for the SF corresponds to (/ field) or 'DATA (/ PSCCH) transmission' 'Relevant' RV 'information (/ field)) may be included. Here, as an example, 'at least (initial)' initial (/ first) transmission '(' SF # (N + D) ') on' SA (/ PSCCH) '(' SF # (N + C) ') 'First) transmit' related 'frequency resource (location)' information (/ field) and / or 'MCS' information (/ field) and / or (described above) 'FIELD # S' (or 'FIELD # Q') ( Or informs the interval between the 'SF PATTERN' information (/ field) and / or 'FIELD # F' (e.g., 'SA (/ PSCCH)' transmission time for 'X th transmission' and 'X th transmission' Can be interpreted as (expanded) as a field) and / or '(applicable) DATA (/ PSCCH) transmission' (/ field) (or '(applicable) DATA (/ PSCCH) transmission') Related 'RV' information (/ field)) (and / or '(DATA / (PSSCH)) FREQUENCY HOPPING' application information (/ field)) may be defined. Here, as an example, when the rule is applied, 'frequency resource (location)' related information ('remaining (of' (K-1) ')' is directly applied on the relevant 'SA (/ PSCCH)' (directly). ) Is not transmitted (/ signaled) and / or 'FIELD # F' values are equal to the interval between the 'SA (/ PSCCH)' transmission time and the 'initial (/ first) transmission' time point associated with the 'initial (/ first) transmission'. V2X UE (S) successfully receives (/ decodes) 'SA (/ PSCCH)' for 'send after' even if it fails to receive (/ decode) 'SA (/ PSCCH)' for 'previous transmission'. (A) '(DATA / (PSSCH)) FREQUENCY HOPPING pattern' information and / or 'SA (/ PSCCH)' related to 'post-transmit' B) 'frequency resource (location)' information related to 'initial (/ first) transmission' and / or (C) 'FIELD # S' (or 'FIELD # Q') information (or 'SF PATTERN' information) and / or The number of times "DATA (/ PSCCH) transmission" is Information (or 'RV' information related to 'DATA (/ PSCCH) transmission') can be combined to identify (or deduce) the data. Here, as an example, 'time resource (location) information' related to 'post transmission' may be identified (/ derived) through 'FIELD # F' on 'SA (/ PSCCH)' related to 'post transmission'. Here, as an example, when the proposed rule is applied (particularly, when '(DATA / (PSSCH)) FREQUENCY HOPPING' operation is applied) 'SA (/ PSCCH)' reception related to 'initial (/ first) transmission' (/ The V2X UE (S) that has successfully decoded may not attempt (partly) to decode (/ receive) the 'SA (/ PSCCH)' related to the 'transmission (of' (K-1) ')'. As another example, it may be interpreted as 'TIMING GAP' between a transmission time of 'FIELD # F' (for example, 'SA (/ PSCCH)') and a transmission time of 'associated data (PSSCH)' (in the proposal rule). Whether or not to reuse the '(frequency) resource' used for previous 'DATA (/ PSSCH)' transmissions (or at some point in the future, when performing other 'TB' related 'POTENTIAL DATA (/ PSSCH)' transmissions). A field indicating an intention may be set (/ signaled) independently (or (all) equally) for each 'SA (/ PSCCH)' transmission. Here, as an example, when the corresponding rule is applied, the V2X UE S may attempt to decode (/ receive) all of the 'SA (/ PSCCH)' related to transmission 'K'. As another example, in the above proposed rule, the V2X TX UE (in case of transmitting one 'TB' in several SF (S)), (in the middle) a preset (/ signaled) rule (e.g. (When 'SA (/ PSCCH)' (/ 'DATA (PSSCH)') of 'HIGHER PRIORITY' transmitted by another V2X UE (S) is detected) 'CURRENT RESOURCE ALLOCATION' is defined in advance (/ signaling) Depending on the 'REQUIREMENT' (for example, LATENCY, RELIABILITY, PRIORITY, FAIRNESS, QOS, etc.), the 'RESOURCE RESELECTION' operation may be performed. Thus, as an example, if the V2X RX UE performs scheduling different from 'previous SA (/ PSCCH)' to 'subordinate SA (/ PSSCH)' (related to 'TB'), Can be followed.

(Example # 2) (in (example # 1)) when sending 'SA (/ PSCCH)' related to 'X th transmission' (eg 'X> 1'), 'FIELD # S' (or 'FIELD #' Q ') may assume that the' Xth transmission 'is' initial (/ first) transmission' and set 'FIELD # S' (or 'FIELD # Q'). As another example, when 'frequency resource (location)' information (/ field) is defined on 'SA (/ PSCCH)' and '(DATA / (PSSCH)) FREQUENCY HOPPING' operation is performed, 'frequency resource ( Location) 'information (/ field) value itself may be set differently (in consideration of the' (DATA / (PSSCH)) FREQUENCY HOPPING pattern ') for each' SA (/ PSCCH) 'transmission. Because, for example, 'SA (/ PSCCH)' related to '(N + 1) th transmission' means '(DATA resource (location))' scheduled by 'SA (/ PSCCH)' related to 'Nth transmission'. This is because it is necessary to designate (/ signal) the changed 'frequency resource (location)' after applying / (PSSCH)) FREQUENCY HOPPING '.

As another example, the V2X UE (S), each time a condition that is set in advance (/ signaled) the (transmission) resources reserved (/ selected) resources (for a certain period (/ period)) is satisfied Can be reselected. Here, as an example, after having the V2X UE (S) to select a counter (COUNTER) value in the predefined (/ signaled) range (" C_RANGE "), the counter is '0' (or '0' When a small value '), it can be made to reselect the (transfer) resources reserved (/ selected) it (for a period (/ period)). Here, as an example, the counter may be (A) a (new) TB transfer (e.g., the wording of the 'TB transfer' is interpreted as 'the actual (successfully) performed TB transfer' only and / or ('sensing result' And / or pre-defined (/ signaling) per 'conflict with omitted TB transmissions' due to 'conflicts with relatively high-priority message transmissions (of other V2X UE (s)'). ) Or (B) a predefined (period) value (e.g. '100MS'), which is reduced (or increased) to a value (e.g. '1') It may be allowed to decrease (or increase) to a signaled value (eg, '1'). Here, as an example, the operation of (re) selecting a counter value (or 'RESET' the counter value) in a predefined (/ signaling) range is related to '(ALL) SEMI-PERSISTENTLY SELECTED RESOURCE (S)'. It may be defined as '(RESOURCE (S)) RESELECTION' triggered. Here, as an example, the 'C_RANGE' value may be set (/ assumed) differently (partly) according to the following (partial) parameter. Here, as an example, the 'C_RANGE' value (according to the range of (specific) parameters) may be predefined or signaled from the network.

( Example # 1) 'V2X UE VELOCITY'. Here, as an example, in the case of 'V2X UE VELOCITY' which is faster (relatively or earlier than a preset (/ signaled) threshold), a (relatively) long (or short) 'C_RANGE' value may be applied.

( Example # 2) '(TRANSMISSION) SYNCHRONIZATION REFERENCE TYPE' (e.g. 'eNB', 'GNSS', 'UE'). Here, as an example, '(TRANSMISSION) SYNCHRONIZATION REFERENCE TYPE' is GNSS (or eNB or UE), (relative to ('(TRANSMISSION) SYNCHRONIZATION REFERENCE TYPE' is eNB (or UE or GNSS)) (relatively) Long (or short) 'C_RANGE' values may apply.

( Example # 3) 'V2X MESSAGE TRANSMISSION (and / or GENERATION) PERIODICITY'. Here, for example, for a 'V2X MESSAGE TRANSMISSION (and / or GENERATION) PERIODICITY' which is long (relatively or above a pre-set (/ signaled) threshold), the (relatively) long (or short) 'C_RANGE' value This may apply.

( Example # 4) 'V2X MESSAGE (and / or SERVICE) TYPE' (e.g. 'EVENT-TRIGGERED MESSAGE', 'PERIODIC MESSAGE' (or '(relatively) small LATENCY REQUIREMENT (and / or (relatively)) High Reliability (/ QOS) REQUIREMENT and / or (relatively high priority) messages ',' (relatively) long LATENCY REQUIREMENT (and / or (relatively) low reliability (/ QOS) REQUIREMENT and / or (relative) Low priority) '), where, for example, for' EVENT-TRIGGERED MESSAGE ', a (relatively) long (or short)' C_RANGE 'value is applied (relative to' PERIODIC MESSAGE '). May be.

( Example # 5) 'V2X MESSAGE (and / or SERVICE) PRIORITY (and / or LATENCY REQUIREMENT and / or RELIABILITY REQUIREMENT and / or QOS REQUIREMENT). Here, for example, for (relatively) low 'V2X MESSAGE (and / or SERVICE) PRIORITY (and / or LATENCY REQUIREMENT and / or RELIABILITY REQUIREMENT and / or QOS REQUIREMENT)' (relative) long (or short) 'C_RANGE' value may apply.

As another example, the V2X TX UE (S) may be configured to perform (V2X MESSAGE) transmission resource (re) reservation (/ selection) operation according to the following (some or all) rules. Here, as an example, the (re) transmission resource (re) reservation (/ selection) operation may be performed randomly within a range (eg, "5 to 15") previously set (/ signaled) by the V2X TX UE (S). It can be triggered (at least) when the selected (transmit resource (re) reserved) counter value ( SEL _ CNTVAL ) reaches "0" (and / or "negative integer value"). Here, in one example, the (selected) counter value is the (real) TRANSPORT BLOCK ( TB ) (/ packet) transmission (and / or (regardless of the ((real)) TB (/ packet) transmission) (selected) counter value (/ Number of transmission resources (of resource reservation (interval) period “P”) (and / or number) derived from (and / or (selected) counter value (/ number) are considered reserved (/ selected). Each time the corresponding reserved (/ selected) transmission resource passes (and (or in the time domain)) and / or (transmitted or created (/ received) on the (LOW LAYER) buffer (and / or PDCP LAYER). ) TB (/ packet) is present (and / or not), it can be reduced by a preset (/ signaled) value (eg, "1"). Here, as an example, in the present invention, the term “(re) reservation (/ selection)” refers to (A) the probability value ( KEEP_P ) (eg, “V2X TX UE (S) pre-set (/ signaling)” If you decide not to retain (/ reuse) the previously selected (transfer) resource based on the aforementioned STEP 3 ”) (for example, a randomly chosen value between“ 0 ”and“ 1 ”may be less than or equal to KEEP_P). Reserving (/ selecting only) existing (transmitted) resources only (regardless of the corresponding probability value (KEEP_P)) based on the sensing results (reserved / selected) And / or (B) the V2X TX UE (S) has previously selected (transmitted based on the preset (/ signaled) probability value (KEEP_P) (or regardless of the corresponding probability value (KEEP_P)). Maintaining (/ reusing) resources (and / or (C) the same finite number of existing (or preconfigured (/ signaled) dogs) (E.g., interpret the SEL_CNTVAL value (and / or interpret it as a value derived from the SEL_CNTVAL value) greater than (or greater than or equal to))) (or a resource such as (old)) to reserve (again) Can be interpreted as (generally). Here, as an example, when the (normally) “(re) reservation (/ selection)” operation is performed, a new (randomly) selection of (transmission resource (re) reservation) counter value (or (transmission resource (re)) Reserve) To inherit (/ preserve / apply) the existing value (SEL_CNTVAL) (or the remaining value (or a preset (/ signaled) value)) without selecting a new (random)) counter value can do.

(Example # 1) As an example, when the V2X TX UE (S) performs transmission resource (re) reservation (/ selection), an infinite number of subframes (of resource reservation (interval) period "P") (/ resource) After (priority) is reserved (/ selected), it is possible to use the reserved (/ selected) resource until the transmission resource (re) reserved (/ selected) operation is triggered. However, as an example, when the corresponding rule is applied, a problem of “ SFN (SYSTEM FRAME NUMBER) WRAP AROUND” may occur.

Hereinafter, for convenience of understanding, an example in which the problem of “ SFN (SYSTEM FRAME NUMBER) WRAP AROUND” will be described through the drawings.

FIG. 22 schematically illustrates an example in which the problem of “SFN (SYSTEM FRAME NUMBER) WRAP AROUND” occurs.

According to FIG. 22, suppose that, for example, there is a V2X TX UE # X that intends to perform transmission resource (re) reservation (/ selection) at a resource reservation (interval) period of “100MS” at the time of SUBFRAME # 0. Here, as an example, assume that all 10240 subframes are set (/ signaled) to V2X resources (full). Here, as an example, in this case, V2X TX UE # X is SUBFRAME # 0, SUBFRAME # 100,... If SUBFRAME # 10200 and SUBFRAME # 10300 should be selected, SUBFRAME # 60 will be selected (due to the limitation of SFN). As a result, in one example, after the (all) subframe selection of the V2X TX UE # X is finished, a second transmission opportunity occurs before SUBFRAME # 100.

On the other hand, in order to solve the problem, when the V2X TX UE (S) performs transmission resource (re) reservation (/ selection), a finite number ( FINI_SFNUM ) (of resource reservation (interval) period "P") It is possible to reserve (/ select) the subframe (/ resource). Hereinafter, an example in which the terminal reserves a finite number of RESOURCEs (ie, 10 * SL_RESOURCE_RESELECTION_COUNTER) according to a predefined rule will be described with reference to the accompanying drawings.

23 is a flowchart of a method for reserving a finite number of resources according to an embodiment of the present invention.

According to FIG. 23, the terminal may make a reservation for a finite number of resources on which V2X communication is performed (S2310). The terminal may select a resource on the selection window and perform a reservation for resources that are repeated based on a specific period from the selected resource, wherein the reserved resource (s) may be a finite number. In this case, the finite number may be proportional to a value of a counter (eg, SL_RESOURCE_RESELECTION_COUNTE) that is arbitrarily selected (or determined) by the terminal, and the counter value may have a positive integer. In addition, the counter value may have a value of 5 or more, and the counter value may have a value of 15 or less. In addition, the finite number may have a value 10 times a counter value arbitrarily selected by the terminal. Hereinafter, an example in which the terminal reserves a finite number of resources will be described in detail.

The terminal may reserve a plurality of resources for which V2X communication is performed, and the plurality of reserved resources may have a finite number. When the terminal reserves a finite number of RESOURCEs, a predefined rule (e.g. 10 * SL_RESOURCE_RESELECTION_COUNTER) may be applied.

As a specific example of a predefined rule, the number of subframes in one set of time and frequency resources related to transmission opportunities of the _PSSCH may be given as a specific value (eg, C _resel ). At this time, C _resel may be defined as 10 * SL_RESOURCE_RESELECTION_COUNTER (when a specific counter (eg, SL_RESOURCE_RESELECTION_COUNTER) is set), otherwise C _resel may be set to 1 (ie, when SL_RESOURCE_RESELECTION_COUNTER is not set). . Herein, a random value of SL_RESOURCE_RESELECTION_COUNTER of 5 or more and 15 or less may be set.

For example, when SL_RESOURCE_RESELECTION_COUNTER is 5, a total of 50 subframes may be reserved for transmission of PSSCH. For example, when SL_RESOURCE_RESELECTION_COUNTER is 15, a total of 150 subframes may be reserved for transmission of PSSCH.

Here, as an example, (the corresponding) finite number is (A) the total number of subframes (/ resources) set (/ signaled) to V2X resources (full) ( TNUM _ V2XSF ) (where, for example, the TNUM_V2XSF value is Can be interpreted as a positive integer value less than or equal to 10240 (including "0") (or “FLOOR (TNUM_V2XSF / Resource Reservation (Interval) Period) (P))” (or “CEILING (TNUM_V2XSF / Resource Reservation ( Interval) (P)) ”or“ FLOOR (10240 / reservation interval (P)) ”or“ CEILING (10240 / reservation interval (P)) ”) (here, for example, FLOOR (X) and CEILING (X) represent a function that derives the largest integer value less than or equal to X, and a function that derives the smallest integer value greater than or equal to X, respectively) or (preset (/ signaled)) TNUM_V2XSF (Or less than or equal to 10240)) and / or (B) (from (serving) base station (or network)) a preset (/ signaling) It can be defined. Here, in one example, the (appropriate) finite number (and / or TNUM_V2XSF value) is interpreted as (and / or equal to) greater than (or greater than or equal to) the SEL_CNTVAL value (and / or the value derived from the SEL_CNTVAL value). One number (and / or TNUM_V2XSF value) may be interpreted as the maximum number of (possibly) reserved (/ selected) subframes (/ resources). Here, as an example, through the application of the rule, even if the (selected) counter value is a positive integer value state, all of the reserved (/ selected) subframes (/ resources) pass (on the time domain) Can be mitigated. Here, in one example, the V2X TX UE (S) defines a (appropriate) finite number (e.g., can be interpreted as (the kind of) the maximum number of subframes (/ resources) that can be reserved (/ selected)), If the SEL_CNTVAL value (and / or the value derived from the SEL_CNTVAL value) is less than (the corresponding) finite number, (exceptionally) SEL_CNTVAL (and / or the number derived from the SEL_CNTVAL value (/ number) and / or smaller) It is also possible to reserve (/ select) a subframe (/ resource) of a value (/ number).

The terminal may perform V2X communication on the reserved number of resources (S2320). As described above, the terminal performs V2X communication on the reserved resource.

Meanwhile, the terminal does not infinitely perform V2X transmission on the reserved resource. That is, the terminal may reselect the reserved transmission resource, and as described above, the (re) transmission resource (re) reservation (/ selection) operation is a range previously set (/ signaled) by the V2X TX UE (S). Triggering (at least) when a randomly selected (transmission resource (re) reservation) counter value ( SEL_CNTVAL ) within (eg, "5-15") becomes "0" (and / or "negative integer value") Can be.

In this case, when the reserved resource no longer remains, the V2X terminal may perform resource reselection in a selection window. In addition, when the V2X terminal has not continuously performed V2X transmission for 1 second, resource reselection may be performed in a selection window, and the V2X terminal may not continuously perform V2X transmission during a preset number of transmission opportunities. If not, the resource reselection in the selection window may be performed. In one example, (applicable) a finite number of (and / or TNUM_V2XSF) reserved (/ selected) subframes (/ resources) are (all in the time domain) passing (and / or preconfigured (/ signaling)). V2X TX when the (selected) counter value is not “0” (and / or “negative integer value”) despite the subframe index (e.g., 10240 (or TNUM_V2XSF)) has passed. Allow the UE (S) to perform a transmission resource (re) reservation (/ selection) operation, but select (randomly) a new (random) transmission value of the (transmission resource (re) reservation) counter (or (transmission resource (re) reservation)) It is possible to inherit (/ hold / apply) the existing value (SEL_CNTVAL) (or the rest of the value (or a preset (/ signaled) value)) without selecting a counter value (newly). There is also.

A specific example of reselecting a transmission resource by the terminal will be described later.

Here, as an example, the term "transfer resource (re) reservation (/ selection) operation" is (A) V2X TX UE (S) is based on the existing (based on the pre-set (/ signaling) probability value (KEEP_P) If you decide not to retain (/ reuse) the selected (transmit) resource (or regardless of the corresponding probability value (KEEP_P)), then the (re) Reservation (/ selection) and / or (B) the V2X TX UE (S) is based on (or based on a pre-set (/ signaled) probability value (KEEP_P) (or regardless of the corresponding probability value (KEEP_P))) To maintain (/ reuse) the selected (transmit) resource (and / or (C) the same finite number as the existing (or pre-set (/ signaled) number) (e.g. SEL_CNTVAL Subframes (or resources (such as)) of a value (and / or a value derived from the SEL_CNTVAL value) that is greater than (or greater than or equal to) the value) It can be interpreted as to (re) scheduling (/ Select)).

(Example # 2) As an example, (when (Example # 1) is applied) V2X TX UE # X (e.g., resource reservation (interval) period "P_X") causes another V2X TX (identified by PSCCH decoding) Determining whether there is a collision (/ overlapping) between the transmission resource of UE #Y reserved (/ selected) resource reservation (interval) period "P_Y" and its own reserved (/ selected) candidate resource (for example, "STEP" 2 ”) assumes (on the candidate resource) that the (finite) number ( NUM_EXTX ) of transfers it assumes (/ remembers ) is performed (or assumes (resources) the resources it reserves / selects). When (assuming) a finite number of subframes (/ resources) of the reservation (interval) period “P_X” are performed, it may be determined according to whether a collision (/ overlap) occurs. Here, as an example (for the case where the rule is applied), V2X TX UE # Y (with (SUBFRAME # (N-10)) PSCCH decoding) is set to SUBFRAME # (N-10 with a resource reservation (interval) period of “1000MS”. ), When it is determined that the transmission resource on SUBFRAME # (N + 990) is reserved (/ selected), V2X TX UE # X (resource reservation (interval) cycle of “100MS”) causes SUBFRAME # N (current time point). When performing (re) reserving (/ selecting) a transmission resource in, the same as (V2X TX UE # Y) on UBFRAME # (N + 90) (in the pre-set (/ TX) SELECTION WINDOW ”) In order to determine whether a candidate resource of a frequency) position is selectable, “SUBFRAME # (N + 90), SUBFRAME # (N + 190), SUBFRAME # (N + 290), SUBFRAME # (N + 390), SUBFRAME # (N + 490), SUBFRAME # (N + 590), SUBFRAME # (N + 690), SUBFRAME # (N + 790), SUBFRAME # (N + 890) (, SUBFRAME # (N + 990)) ”(and / Or “SUBFRAME # (N + (990-100 * 9)), SUBFRAME # (N + (990-100 * 8)), SUBFRAME # (N + (990-100 * 7)), SUBFRAME # (N + (990-100 * 6)), SUBFRAME # (N + (990-100 * 5)), SUBFRAME # (N + (990-100 * 4)), SUBFRAME # (N + (990-100 * 3)), SUBFRAME # (N + (990-100 * 2)), SUBFRAME # (N + (990-100)) (, SUBFRAME # (N + 990)) ”) Monitoring can be performed. Here, as an example, this type of monitoring is the same (frequency) that V2X TX UE # X is reserved (/ selected) by V2X TX UE # Y (in a pre-set (/ RE) TX RESOURCE) SELECTION WINDOW). ) Whether the candidate resource ( SUBFRAME #Z (e.g. “Z = (N + 90))) of the location is selectable is (optionally) V2X TX UE # Y (based on“ P_Y ”) (additionally) reserved ( (Optional) can be interpreted as a resource (/ subframe) viewpoint (e.g. SUBFRAME #G (e.g. "G = (N + 990)")) (e.g. "UPPER BOUND" ) And SUBFRAME # (Z + P_X * K) (where, for example, ”0 ≤ K ≤ (“ (Z + P_X * M) ”value is less than or equal to the value of“ G ”(integer) M value) ”) (and / or SUBFRAME # Z and SUBFRAME # (G-P_X * R) (where, for example,“ 0 ≤ R ≤ (“(G-P_X * H)”) Condition that is greater than or equal to the minimum subframe index value in the preset (/ assumed) “(TX RESOURCE) SELECTION WINDOW” Group maximum (constant) H values), depending on whether you are "), the overlap occurs between), it can be seen to be determined (/ determination). Here, as an example, when the proposed rule (of (Example # 2)) is applied, the V2X TX UE (S) collides with the number of resources (for example, (Example # 1)) reserved (/ selected) (/ It can be interpreted that the number of resources (eg, (Example # 2)) that need to look into the future to determine the overlap may be different. Here, as another example (when the corresponding rule is applied), V2X TX UE # Y (with (SUBFRAME # (N-10)) PSCCH decoding) is set to SUBFRAME # (N with a resource reservation (interval) period of “1000MS”. -10) If it is found that the transmission resource on SUBFRAME # (N + 990) is reserved (/ selected), V2X TX UE # X (resource reservation (interval) cycle of “100MS”) causes SUBFRAME # N (currently When performing (re) reserving (/ selecting) a transmission resource at a time point), a candidate resource (of the same (frequency) position as V2X TX UE # Y) on SUBFRAME # (N + 90) is assumed to Finite) count (e.g., “9”) (e.g., the corresponding (finite) count is the reserved (/ selected) transmission resource of V2X TX UE # Y (e.g., SUBFRAME # (N + 990 )) Transmissions (e.g. SUBFRAME # (N + 90), SUBFRAME # (N + 190)) of transmissions (which can be set to a (maximum) (integer) value where the maximum value of the monitoring subframe index does not become larger than the time point) , SUBFRAME # (N + 290), SUBFRAME # (N + 390), SUBFRAME # (N + 490), SUBFRAME # (N + 590) , When (S + FRAME # (N + 690), SUBFRAME # (N + 790), SUBFRAME # (N + 890)) is performed, the reserved (/ selected) transmission resource of V2X TX UE # Y (e.g., SUBFRAME # Whether or not (N + 990)) collides with (or overlaps) may be determined. Here, as an example, since the collision does not collide (or overlap), it is possible to select (final). In one example, the NUM_EXTX value and the FINI_SFNUM value (see example # 1) may be set (/ signaled) independently (/ differently) (or identically). Here, as an example, the FINI_SFNUM value (/ signaling) (and / or) is set to a common value (or independent value) between V2X UEs (GROUP) (sharing the V2X resource pool) on the same carrier (/ frequency). The NUM_EXTX value is set to an independent value (e.g., set by the upper layer of the terminal) (or common value) between V2X UEs (GROUP) (sharing the V2X resource pool) on the same carrier (/ frequency) ( / Signaling)).

(Example # 3) As an example, if the (selected) counter value is decremented per (actual) TB (/ packet) transmission by a pre-set (/ signaled) value (eg, “1”), If there is no TB (/ packet) to send to V2X TX UE # M (for long time) (on (LOW LAYER) buffer (and / or PDCP LAYER)) (and / or no (real) TB (/ packet) transmission) , The decrement of the (selected) counter value will cease, and when the TB (/ packet) to be sent (after a long time) reappears (and / or when (actual) TB (/ packet) transfer is performed), (applicable) V2X TX UE # M assumes that it still has (previously) reserved (/ selected) resources (since the (selected) counter value is a positive integer) and uses the (incorrectly) resources incorrectly. .

The terminal may reselect the reserved transmission resource, and the (re) transmission resource (re) reservation (/ selection) operation may be performed by the V2X TX UE (S) in a preset range (/ signaling) (for example, “5”. ~ 15 ”) can be triggered (at least) when a randomly selected (transmission resource (re) reservation) counter value ( SEL _ CNTVAL ) reaches" 0 "(and / or" negative integer value "). Here, as an example, when the UE performs the actual transmission, the counter value may be decreased by '1', and when the counter value is 0, the UE may perform the resource rescheduling operation. In other words, in this case, the transmission resource re-reservation may occur (triggered) only when the terminal actually performs transmission (on a previously reserved resource).

As mentioned above, the value of the counter (which triggers resource re-reservation) is reduced only if the actual packet transmission by the terminal (on the pre-reserved resource) has to be performed, if (pre-reserved) If the counter value does not become “0” (and / or “negative integer value”) even though the number of resources has passed (on the time domain) (forever, resource rebooking has not been triggered). Deadlock problems can occur.

Accordingly, in order to solve the above-mentioned problem, a method of performing resource rescheduling (that is, resource reselection) may be described below with reference to the drawings (even if the value of the counter does not become 0).

24 is a flowchart illustrating a method for reselecting a resource by a terminal according to an embodiment of the present invention.

According to FIG. 24, the terminal determines whether a resource reselection condition is satisfied (S2410). There may be a plurality of resource reselection conditions. The terminal may perform resource reselection if at least one of the plurality of resource reselection conditions is satisfied. Here, for example, to solve the problem, a V2X TX UE # M (where the (selected) counter value is a positive integer value state) causes a threshold (time) value above a preset (/ signaled) value. If there is no TB (/ packet) to be sent to (on the (LOW LAYER) buffer (and / or PDCP LAYER)) (and / or if (real) TB (/ packet) transfer is not performed (continuously)) (and / Or (current) subframe index exceeds the value of 10240 (or TNUM_V2XSF) and / or (finite number of) subframes (/ resources) reserved (/ selected) by (all in time domain) When passed, perform the transmission resource (re) reservation (/ selection) operation, but select the (transmission resource (re) reservation) counter value newly (randomly) or select the (transmission resource (re) reservation) counter value. SEL_CNTVAL (or not (newly selected)) (or other values that are preset (/ signaled)) Value)) can be inherited (/ maintained / applied).

In summary, the resource reselection condition of the UE is (A) when there are no more resources for V2X transmission (for example, as described above, the subframe (/ resource) reserved by itself (/ resource) (Both) '(B) if the UE has not performed packet transmission for a continuous 1 second (e.g., as described above,' before the pre-set (/ signaled) threshold time value ( (Continued) TB (/ packet) transmission is not performed '), (C) when the UE skips a predetermined number of consecutive transmission opportunities (for example, as described above,' pre-set (/ May be present when TB (/ packet) transmission is not performed (continuously) above the signaled threshold). Hereinafter, specific examples of the aforementioned resource reselection condition will be described.

(A) If there are no more resources left for V2X transmissions,

The terminal may perform resource reselection when there are no more resources associated with the configured sidelink grant. That is, when the UE no longer has resources associated with the configured sidelink grant and there is a new MAC PDU to be transmitted to the UE, resource reselection may be triggered. (Ie, in the above-described case, the UE may perform resource reselection.)

In one example, (applicable) a finite number of (and / or TNUM_V2XSF) reserved (/ selected) subframes (/ resources) are (all in the time domain) passing (and / or preconfigured (/ signaling)). V2X TX when the (selected) counter value is not “0” (and / or “negative integer value”) despite the subframe index (e.g., 10240 (or TNUM_V2XSF)) has passed. Allow the UE (S) to perform a transmission resource (re) reservation (/ selection) operation, but select (randomly) a new (random) transmission value of the (transmission resource (re) reservation) counter (or (transmission resource (re) reservation)) It is possible to inherit (/ hold / apply) the existing value (SEL_CNTVAL) (or the rest of the value (or a preset (/ signaled) value)) without selecting a counter value (newly). There is also.

(B) the terminal does not perform a packet transmission for a continuous 1 second,

(Last) For 1 second, if transmission or retransmission is not performed (by the MAC entity) on the resource indicated by the established sidelink grant, the terminal may perform resource reselection. That is, when the terminal does not perform transmission or retransmission on a continuous transmission opportunity of 1 second, resource reselection may be triggered.

(C) when the terminal skips a predetermined number of consecutive transmission opportunities,

If a preset value is set for the UE and the number of unused transmission opportunities (on the resource indicated by the configured sidelink grant) is the same as the preset value, the UE may perform resource reselection. In other words, when a specific value is set in the terminal and the terminal continuously skips the transmission opportunity by the number of the specific value, the terminal may perform resource reselection.

That is, if a terminal skips a continuous transmission opportunity of N (where N is a positive integer), resource reselection may be triggered. Here, when the condition is used, N is set to the terminal, and N may have a value of [1, 2, 3, 4, 5, 6, 7, 8, 9].

For example, when skipping '5' consecutive transmission opportunities to the terminal, when the terminal is configured to perform the resource reselection, the terminal reselects the resources when the transmission does not perform for five consecutive transmission opportunities Can be performed.

Thereafter, when the resource reselection condition is satisfied, the terminal may perform reselection for a resource on which V2X communication is performed (S2420). In other words, when the resource reselection condition is satisfied, the terminal may reselect a resource on which V2X communication is performed, and then the terminal may perform V2X communication on the selected resource. For example, as described above, the terminal (A) if the resources for the V2X transmission no longer remains (for example, as described above, the 'subframe (/ resources) reserved by itself (/ resources) is ( All)), (B) if the UE has not performed packet transmission for a continuous 1 second (e.g., as described above, 'more than the preset (/ signaled) threshold time value (continuous) TB (/ packet) transmission is not performed '), or (C) the terminal skips a predetermined number of consecutive transmission opportunities (for example, as described above, When TB (/ packet) transmission is not performed (continuously) above the signaled threshold value '), V2X communication may be performed on the selected resource by reselecting a resource on which V2X communication is performed.

Thereafter, the terminal may perform the V2X communication based on the selected resource (S2430). Here, as described above, the selected resource may mean a resource determined on the basis of a SELECTION WINDOW configured to satisfy a LATENCY REQUIREMENT (that is, a resource on a selection window that satisfies a latency request). In addition, as described above (or described later), the terminal may select a subframe within a selection window based on a sensing result performed during the terminal-specific sensing interval, and the terminal may select a transmission reservation resource based on the selected subframe. And V2X communication on the reserved resource. Specific examples of performing V2X communication based on the resource selected by the terminal are as described above (or described later), and thus, detailed descriptions thereof will be omitted.

Here, as an example, the term "transfer resource (re) reservation (/ selection) operation" is (A) V2X TX UE (S) is based on the existing (based on the pre-set (/ signaling) probability value (KEEP_P) If you decide not to retain (/ reuse) the selected (transmit) resource (or regardless of the corresponding probability value (KEEP_P)), then the (re) Reservation (/ selection) and / or (B) the V2X TX UE (S) is based on (or based on a pre-set (/ signaled) probability value (KEEP_P) (or regardless of the corresponding probability value (KEEP_P))) To maintain (/ reuse) the selected (transmit) resource (and / or (C) the same finite number as the existing (or pre-set (/ signaled) number) (e.g. SEL_CNTVAL Subframes (or resources (such as)) of a value (and / or a value derived from the SEL_CNTVAL value) that is greater than (or greater than or equal to) the value) It can be interpreted as to (re) scheduling (/ Select)).

(Example # 4) In one example, a V2X TX UE # U may be configured to perform a (selected / reserved) subframe of (or select) a transmission resource (re) reservation and / or another V2X TX UE # Z. (Resource) at the location) Resource reservation (interval) A finite (/ infinite) number of (reserved (/ optional)) subframes (/ resource) of “P” exceed the (previous) 10240th subframe (eg For example, if the "Z" th subframe (where, for example, "Z" is a positive integer value greater than "10240"), then "MOD (Z, 10240) within the next (or later) 10240 subframes. (Here, for example, MOD (X, Y) represents a function that derives the remaining values when X is divided by Y.) ”at the interval of (re) resource reservation (interval) period“ P ”from the subframe (Subframes / resource) can be considered to be reserved.

(Example # 5) As an example, ((Example # 1) and / or (Example # 2) and / or (Example # 3) and / or (Example # 4)) (let V2X UE (S)) (Finite (/ infinite) number of subframes (/ resource)) The reservation (/ selection) itself is outside the SFN range (or TNUM_V2XSF range) (by SFN WRAP AROUND), but the V2X UE (S) Resource Reservation (Interval) Period (P), while keeping the odd (time) subframe (/ resources) excluded (SKIP) (and / or (finite (/ infinite)) ) Number of subframes (/ resources)) reservation (/ selection) can be operated by itself in the form of increasing the SFN range (or TNUM_V2XSF range).

(Example # 7) As an example, the following description shows a method for supporting an efficient (V2X message (/ TB)) transmission operation of a V2X TX UE (S). Hereinafter, the UE reserves 10 * C subframes at a resource reservation period P interval, where C may mean SL_RESOURCE_RESELECTION_COUNTER determined by MAC.

(A) As described above, there are two problems in which a UE reserves a 10 * C subframe at a resource reservation period P interval.

First, the UE reserves a finite number of subframes, but SL_RESOURCE_RESELECTION_COUNTER can be reduced only when the MAC PDU is transmitted. Therefore, when the upper layer stops packet generation for a specific time interval, and skips transmission in many reserved subframes, the UE no longer reserves the reserved resources and more resources for the transmission of newly arrived packets. It may not be left anymore.

In addition, if the time interval of the set of reserved subframes exceeds the DFN (D2D FRAME NUMBER) range (that is, 10 * C * P> T _max , T _max is 10240 or 10176), the subframe in the second DFN range The number may not be divided by 100 (ie, division by 100 may result in the remainder).

For example, as shown in FIG. 22, when the V2V subframe has an index range of 10240, the UE reserves a subframe for the index {0, 100, ..., 10200, 10300, ..., 14900}. In this case, since the subframe numbers from 10300 to 14900 correspond to a range beyond the DFN range, subframes for {0, 100, ..., 10200, 60, 160, ..., 3660} are actually reserved. Can be.

(B) In the following, to provide a method for solving the above two problems.

First, in order to solve the first problem, even though the resources reserved by the terminal no longer remain, when the SL_RESOURCE_RESELECTION_COUNTER is still greater than zero, the terminal may extend the resource reservation.

In order to solve the second problem, the number of reserved subframes can be set independently of the number of counters. In addition, the number of reserved subframes may be set smaller than the counter value. For example, the terminal may reserve a set of subframes up to the boundary of the current DFN range when resource reservation is triggered.

25 is an example of a method of performing resource reservation in consideration of the above-mentioned proposal.

According to FIG. 25, in consideration of the above two proposals, the UE may first determine a set of subframes ending before the DFN boundary and repeat resource reservation at the same resource reservation interval if more resources are needed. .

(C) The above proposal is summarized as follows.

Proposal 1: If the terminal no longer has a reserved resource, but the SL_RESOURCE_RESELECTION_COUNTER is still greater than zero, the terminal can extend the resource reservation.

Proposal 2: When resource reservation is triggered, the UE can reserve a set of subframes up to the boundary of the current DFN range.

An example of a transmission resource (re) reservation (/ selection) operation of the V2X TX UE (S) may be shown in Table 2 below.

TABLE 2

(Example # 6) In one example, a V2X TX UE (S) is configured to transmit (re) reserve (/ select) transmission resources according to Table 2 (e.g., "STEP 2/3" described above (or described later)). To perform the operation. Here, as an example, the value of “RESOURCE RESERVATION FIELD ( RR_FIELD )” in the SCI format is defined in advance (/ signaling) of the “RESOURCE RESERVATION INTERVAL ( RR_ INV )” value (/ signaled) from the (terminal) upper layer. It can be specified as the quotient (/ value) ( I_VALUE ) divided by the set value ( P_STEP ) (eg, “P_STEP = 100”). Here, as an example, the I_VALUE value may be set (/ signaled) in the range of (maximum) “1 ≦ I_VALUE ≦ 10”. Here, as an example, whether or not a particular I_VALUE value can be selected (/ allowed) is in the form of “CARRIER (/ POOL) -SPECIFIC NETWORK (PRE) CONFIGURATION” (predefined signaling (e.g. X on 10-BIT BITMAP). Bit may indicate whether the Xth I_VALUE value is selectable (/ allowed). Here, as an example, the selection restriction of a particular I_VALUE value ( I_ RESVAL ) may include (A) failing to set (/ signal) the RR_INV value of the (I_RESVAL * P_STEP ”value (by the terminal) and / or (B). ) Can be interpreted as requiring (/ signaling) another I_VALUE value (rather than I_RESVAL) that can represent the (closest) (terminal) value closest to (in fact) the desired RR_INV value.

Meanwhile, when transmission is performed while the UE performs sensing (in the sensing window), that is, the UE may not perform sensing (due to a half duplex problem) for a subframe in which V2X transmission is performed in the sensing window. have. In this case, when the UE transmits a V2X message on a subframe in which the UE cannot perform sensing and a subframe corresponding to specific periods, the UE transmits a V2X message based on the subframe in which the UE does not perform sensing. Will result.

Accordingly, in order to solve the problem of transmitting a V2X message based on a subframe in which the terminal has not performed sensing, excluding a subframe (in a selection window) related to a subframe in which the terminal has not sensed. The method is provided through the drawings.

FIG. 26 is a flowchart of a method of excluding a subframe (in a selection window) related to a subframe in which a terminal does not perform sensing according to an embodiment of the present invention.

According to FIG. 26, the terminal selects a subframe (in a selection window) except for a subframe (in a selection window) related to the subframe in which a transmission is performed during the sensing period (S2610). In other words, the terminal may select a plurality of subframes other than the subframes in the excluded selection window except for the subframes in the selection window related to the subframe in which the transmission is performed during the sensing period among the plurality of subframes in the selection window. You can select from subframes.

Here, when the UE selects a subframe in the selection window, the subframe according to the resource reservation period of the selected subframe is detected by the UE. It may mean a subframe that may not be performed and a subframe that overlaps with a subframe corresponding to specific periods. For convenience of explanation, the present contents will be described below with reference to the drawings.

FIG. 27 illustrates an example of excluding a subframe (in a selection window) related to a subframe in which the terminal has not performed sensing.

According to FIG. 27, for example, the first subframe may mean a subframe in which the terminal has not performed sensing. It may be assumed that the first subframe and the subframe corresponding to the specific period are the third subframes.

Here, when the second subframe in the selection window is selected, there are a plurality of subframes to be reserved according to a resource reservation period for the selected second subframe, and one (or plurality) of subframes to be reserved is When overlapping with the third subframe, the terminal may not select the second subframe in the selection window (that is, the selection may be excluded).

Returning to FIG. 26 and generalizing this, for example, in the subframe #k (within the sensing window) (the V2X message transmission is performed), the UE did not perform the sensing, and the subframe # (y + P * j) and the sub When frame # (k + 100 * i) overlaps, the terminal may exclude subframe #y within the selection window from resource reservation selection. Here, as described above, the subframe #k may correspond to a subframe in which the terminal does not perform sensing, and the subframe #y may mean a subframe within the selection window. In addition, P may mean a resource reservation period of the terminal, for example, P may have a value of 100ms. J may mean a value of 0, 1, 2, ..., C _{_ resel} -1, and C _{_ resel} is a value of a specific counter value (for example, 10 * SL_RESOURCE_RESELECTION_COUNTER) as described above. It may mean. Since the contents of the specific counter (that is, SL_RESOURCE_RESELECTION_COUNTER) are as described above, a detailed description thereof will be omitted. In addition, i can mean an element in the set that is limited by the carrier specific setting. That is, i denotes a value at which the base station can allow a reservation, and a value associated with a specific period (eg, when i is 2, a specific period (eg 1 hop) is 100 * i = 200ms). Can be. At this time, i may have a value of 2, 4, 6, 8, for example.

Here, in one example, in STEP 5 described in Table 2, V2X TX UE (S), if in STEP 2

Is not monitored by your own V2X message transfer behavior (and / or your own V2X message transfer behavior

If no other V2X TX UE (S) related PSCCH decoding and (interlinked) PSSCH DM-RS RSRP (and / or S-RSSI) measurement operations have been performed), R _{X in} R _{X, Y} belonging to S _{A , Y + RR_ INVTX * j} is

(And / or

If it overlaps with (some) resource (s) that may be selected (/ reserved) by another V2X TX UE (S) on Rx _{, Y} may be (additionally) excluded from the S _A set. Here, for example, the value of "J" is "0, 1,..." , (C _RESEL- 1) (see Table 2) ”. Here, in one example, “RR_INVTX” means its own (RESOURCE RESERVATION INTERVAL) value (set (/ signaled) from the upper layer), and “I_CANVAL” (before) “CARRIER (/ POOL) -SPECIFIC NETWORK ( It can be interpreted (limitedly) as value (s) belonging to the selectable (/ allowable) "I_VALUE SET" specified in the form PRE) CONFIGURATION ". Here, as an example, when the rule is applied, resources (for example, the V2X TX UE (S) is not monitored by its V2X message transmission operation in STEP 2 (eg,

Is generated) _{, and} when determining whether to exclude (addition) of R _{X, Y} from the set of S _A , the (real) selectable (/ permissible) (I / VALUE SET) (and / or It can be interpreted as considering only “RESOURCE RESERVATION INTERVAL”).

Thereafter, the terminal may perform V2X communication based on the selected subframe (S2620). Here, as described above, the selected subframe (or resource) means a resource determined on the basis of (SLECTION WINDOW) configured within a range that satisfies LATENCY REQUIREMENT (ie, a resource on a selection window that satisfies the latency request). can do. In addition, as described above (or described later), the terminal may select a subframe within a selection window based on a sensing result performed during the terminal-specific sensing interval, and the terminal may select a transmission reservation resource based on the selected subframe. And V2X communication on the reserved resource. As described above, the UE performing V2X communication on the selected subframe may mean that the UE performs V2X communication on the reserved subframe in association with the selected subframe. Specific examples of performing V2X communication based on the resource selected by the terminal are as described above (or described later), and thus, detailed descriptions thereof will be omitted.

Here, as another example, in STEP 5 described in Table 2, V2X TX UE (S), if in STEP 2

Is not monitored by your own V2X message transfer behavior (and / or your own V2X message transfer behavior

If no other V2X TX UE (S) related PSCCH decoding and (interlinked) PSSCH DM-RS RSRP (and / or S-RSSI) measurement operations have been performed), R _{X in} R _{X, Y} belonging to S _{A , Y + RR_ INVTX * J}

(And / or

If it overlaps with (some) resource (s) that may be selected (/ reserved) by another V2X TX UE (S) on Rx _{, Y} may be (additionally) excluded from the S _A set. Here, in one example, “I_CANVAL_X” is (pre-) the maximum value (s) belonging to the selectable (/ allowable) “I_VALUE SET” specified in the form “CARRIER (/ POOL) -SPECIFIC NETWORK (PRE) CONFIGURATION”. Or a minimum value or a specific value). Here, as another example, in STEP 5 described in Table 2, the V2X TX UE (S), if

If you are not monitored in STEP 2 with your own V2X message transfer behavior (and / or with your V2X message transfer behavior)

From other V2X TX UE (S) related PSCCH decoding and (interlocked) PSSCH DM-RS RSRP (and / or S-RSSI) did not perform a measurement operation side), R _{X, Y} to S _A set on the (further) You can exclude it. Here, as an example, "(N-1001) ≤ (Y-I_CANVAL * P_STEP) ≤ (N-2)" (where, for example, SUBFRAME # N time point (from upper layer) (transmission) resource (re) reservation (/ Can be interpreted as the time when performance is set (/ signaling)) (and / or "P_STEP = 100"). Here, as another example, in STEP 5 described in Table 2, the V2X TX UE (S), if

If you are not monitored in STEP 2 with your own V2X message transfer behavior (and / or with your V2X message transfer behavior)

From other V2X TX UE (S) related PSCCH decoding and (interlocked) PSSCH DM-RS RSRP (and / or S-RSSI) did not perform a measurement operation side), R _{X, Y} to S _A set on the (further) You can exclude it. Here, as an example, “(N-1001) ≤ (Y-I_CANVAL_Q * P_STEP * K) ≤ (N-2)" (where, for example, the SUBFRAME # N viewpoint is from (upper layer) (transmission) resource (re Can be interpreted as a point in time when scheduled (/ selected) execution is set (/ signaled) (and / or “P_STEP = 100”) and / or “K = NON-NEGATIVE INTEGER”. Here, in one example, “I_CANVAL_Q” is a value (s) belonging to the selectable (/ allowable) “I_VALUE SET” (specified in the form “CARRIER (/ POOL) -SPECIFIC NETWORK (PRE) CONFIGURATION”) (and / Or can be set (/ signaled) to the minimum (or maximum or specific value) of the value (s) belonging to the selectable (/ permissible) "I_VALUE SET". Here, as an example, when the (partial) rule is applied, when determining whether to exclude (addition) of R _{X, Y} from the S _A set, (A) J value is a predetermined value (/ signaling) previously set ( (Eg, “J = 1 (/ 0)”) (and / or “RR_INVTX * J” (or “P_STEP * J”) (on a particular carrier (/ pool)) (actual) selection (/ Allowable) A J value equal to the maximum possible (or minimum) “RESOURCE RESERVATION INTERVAL” (or a specific “RESOURCE RESERVATION INTERVAL” pre-set (/ signaled)) (or less than (or greater than or equal to) the derived J value. The same value (s))) and / or (B) the specific value (s) (e.g., "RR_INVTX = 1000MS") previously set (/ signaled) to the RR_INVTX value Or (on a specific carrier // pool) (actual) select (/ allow) the maximum possible (or minimum) “RESOURCE RESERVATION INTERVAL” (or the corresponding maximum (or minimum) “RESOURCE RESERVATION INT ERVAL ”may be assumed to be less than (or greater than) the same value (s)). Here, as an example, the proposed method is a message (/ packet) related priority value (and / or (corresponding) carrier (/ full) related CONGESTION LEVEL value) that the V2X TX UE (S) to transmit in advance (/ signaling It may be limited to apply only if it is smaller (or larger) than the threshold.

(Example # 8) As an example, (V2X UE (S)) effectively reflects resources (/ subframes) that are not monitored (/ sensed) by its own transmission operation in "RESOURCE EXCLUSION PROCEDURE (BASED ON PSSCH-RSRP MEASUREMENT)". Here's how.

When a single transmission of TB is performed by other terminals in subframe #k, it may be difficult to obtain accurate information of the PSSCH-RSRP on the skipped subframe #k. Accordingly, when the subframe # (y + P * j) overlaps the subframe # (k + 100 * i), it may be considered that the terminal #A excludes the subframe #k existing within the selection window of the terminal. have. In this case, as described above, P may mean a resource reservation interval of the terminal, j may mean 0, 1, ..., 10 * SL_RESOURCE_RESELECTION_COUNTER-1. I may also mean (possible) elements in the set which are limited by carrier specific network (pre) configuration.

(Here, as an example, the value of "100" on "SUBFRAME # (K + 100 * I)" is the V2X of "SHORTER RESOURCE RESERVATION PERIOD (/ INTERVAL)" on a (specific) resource pool that has been preset (/ signaled). UE (S) (and / or V2X UE (S) performing a (relatively) short period V2X message (/ traffic) transmission) ( SHORTP _ UE (S) ) and “(RELATIVELY) LONGER RESOURCE RESERVATION PERIOD (/ V2X UE (S) (and / or V2X UE (S) which performs (relatively) long period V2X message (/ Traffic) ) coexists when LONGP_UE (S) coexists) (A) When SHORTP_UE (S) performs a sensing operation and / or (B) LONGP_UE (S) performs a sensing operation (for SHORTP_UE (S)), it is set to a different value (preset (/ signaled)). Can be specified.)

With the above approach, terminal #A may exclude all resources (in the terminal's selection window) that overlap with the transmission of another terminal that may be scheduled from the skipped subframe #k. Hereinafter, this will be described with reference to the drawings.

28 to 30 show examples reflected in “RESOURCE EXCLUSION PROCEDURE (BASED ON PSSCH-RSRP MEASUREMENT)”.

According to FIGS. 28 to 30, the set of i may be limited as {2, 4}, and P and SL_RESOURCE_RESELECTION_COUNTER may be set to 200 ms and 5, respectively.

In the case of FIG. 28, “subframe # (k + 100 * 2) (ie, i = 2) and subfram # (y + 200 * 0) (ie, j = 0)”, “subframe # (k + 100 * 4) ) (ie, i = 4) and subfram # (y + 200 * 1) (ie, j = 1) ”, subframe #k (within the selection window) may be excluded from the selection.

In the case of FIG. 29, due to “subframe # (k + 100 * 4) (ie, i = 4) and subfram # (y + 200 * 0) (ie, j = 0)”, the sub (within the selection window) Frame #k may be excluded from the selection.

However, in the case of FIG. 30, since there is no subframe in the selection window in which overlap occurs as described above, the subtraction in the selection may not include the subframe in the selection window.

In conclusion, the following proposal is provided.

Proposal: To handle skipped subframe #k (due to its own transmission) in the resource exclusion procedure, the following solution may be proposed. UE #a may need to exclude subframe #y within its selection window if subframe # (y + P * j) may overlap with subframe # (k + 100 * i). Here, P may refer to the resource reservation interval of the terminal, j is 0, 1, ..., (10 * SL_RESOURCE_RESELECTION_COUNTER-1), i is all (use) of the set limited by the carrier-specific network (pre) configuration Element).

As another example, if a bitmap of a predetermined (/ signaled) length (eg, “16”, “20”, “100”) is repeatedly applied for V2X resource pool setup, Subframes configured for SLSS transmission (/ signaled) are excluded from the (candidate) subframes that can be set (/ signaled) to the V2X resource pool, and the corresponding bitmap (applied) is “TRUNCATED” in the “DFN RANGE END”. Problems may arise. Here, for example, to solve the problem, increase the (existing) "DFN RANGE" value (e.g. "10240" or "10176") (e.g. HYPER-SFN (/ HYPER-DFN) Can be interpreted in such a way). Here, in one example, the (increased) “(max) DFN RANGE” value is “10240 (/ 10176) * H_VAL” (or “10240 (/ 10176) * H_MAXVAL”) (and / or “MAX DFN RANGE * H_VAL” (Or “MAX DFN RANGE * H_MAXVAL”). Here, for example, (A) H_VAL value (/ index) (/) (B) Setable (/ usable) H_VAL (index) range and / or (C) Maximum value of H_VAL (/ maxindex) ( H_ MAXVAL) (and / or minimum value (Min / index) (H_ MINVAL)), such as a network (or serving cell) is defined in advance (the upper (/ physical) layer) signaling (and / or (SYNCH. SOURCE) terminal Via the (newly defined) field (or predefined D2D channel / signal) on the PSBCH (“CARRIER (/ POOL / CELL) -SPECIFIC (PRE) CONFIGURATION” type and / or “V2X POOL (PRE) CONFIGURATION”). As part of, you can set (/ signaling) in advance.

Figure 31 shows an example of the case of increasing the (old) "DFN RANGE" value (for example, "10240" or "10176"). Here, as an example, it is assumed that the H_VAL (and / or H_MAXVAL) value (for example, "H" in Figure 31) is set to "5". Here, in one example, the (incremented) “(max) DFN RANGE” value can be divided (and / or remaining) by the bitmap length (specified / signaled) relative to the V2X resource pool configuration (and / or (V2X resource)). On (whole) subframes set to full (/ signaled) (on (specific carrier // full)) (actual) selectable (/ allowable) (maximum (or minimum) or preset (/ signaled) ) H_VAL value (and / or H_MAXVAL) (and / or V2X resource pool configuration) to enable (correct) "WRAP AROUND" in cycles that are multiples of "RESOURCE RESERVATION INTERVAL" (eg "100MS"). (Signaling) related bitmap values) can be (limited) set (/ signaling). Here, as an example, when the rule is applied, the V2X UE (S) advances the H_VAL value whenever the (existing) “(max) DFN RANGE” value (eg, “1024 (/ 10240)”) passes. Increment by the value set (/ signaled) to (for example, “1”), but from (V2X) subframe of relatively small index within (V2X) subframe (set) based on the same H_VAL value Message) transmission (and / or V2X communication). As another example, in a sensing operation, “SUBFRAME INDEX” uses “LOGICAL INDEX” in a (V2X) resource pool. Here, as an example, when another signal (preset) and the (V2X) resource pool are “TDM”, the physical time interval may be relatively large. Here, as an example, in this case, the V2X TX UE (S) may be made to use the "RESOURCE RESERVATION INTERVAL" value as a smaller value.

On the other hand, if the rules described above are applied (e.g., as previously described), the (old) "DFN RANGE" value (e.g., "10240" or "10176") is increased (e.g., some sort of HYPER-SFN (/ HYPER-DFN) method), V2X communication can be performed as follows.

(A) (e.g., when the bitmap for a V2V subframe does not repeat an integer number of times within the DFN period [RAN1, RAN2]), V2V may be multiplexed with other signals / channels.

(B) Currently, Tmax, which means the DFN range for V2V, that is, the number of subframes that can be allocated to V2V, may be 10240 or 10176 depending on the SLSS resource configuration.

On the other hand, the length of the bitmap representing the V2V subframe for the resource pool may be 16, 20, or 100. Accordingly, as described above (eg, in case of FIG. 22), a case may occur in which the DFN range is not divided by the bitmap length unit.

A fundamental solution to this problem may be to change the DFN range (ie, Tmax) so that it is always divided by the bitmap length. This may mean increasing the DFN range to be a multiple of the bitmap length. Thus, the concept of "hyper SFN (H-SFN)" may be introduced to increase the SFN range.

Here, when the H-SFN is provided in the SystemInformationBlockType1-BR, the modification period boundary for the BL UE and the UE in the CE may be defined by an SFN value of (H-SFN * 1024 + SFN) mod m = 0. Here, with respect to NB-IoT, H-SFN can always be provided and the modification period boundary can be defined by an SFN value with (H-SFN * 1024 + SFN) mod m = 0. The modification period may be set by the system information.

An eDRX acquisition cycle may be defined to enable notification of system information update for an RRC_IDLE terminal that uses an eDRX cycle longer than or equal to the modification cycle. The boundary of the eDRX acquisition period may be determined by an H-SFN value of H-SFN mod 256 = 0. In particular, in the case of NB-IoT, the boundary of the eDRX acquisition period may be determined by an H-SFN value of H-SFN mod 1024 = 0.

32 shows an example of transmitting updated system information.

According to FIG. 32, if the network changes (some) system information, the network may first notify the terminals about this change. In the next modification cycle, the network can send updated system information. Upon receiving the change notification, the terminal can immediately acquire new system information from the start of the next modification cycle using a DRX cycle less than or equal to the modification cycle.

The transmitted system information, that is, SystemInformationBlockType1 may be defined as shown in Table 3 below.

TABLE 3

Here, 'hyperSFN' indicates a hyper SFN that increases by one when the SFN is wrapped, and with respect to 'eDRX-Allowed', the presence of this field indicates whether idle mode extended DRX is allowed in the cell. If there is no eDRX permission, the terminal should stop using extended DRX in idle mode.

Using a similar principle, you can define a "hyper DFN" to increase the range of DFNs. The V2V subframe index in the logical domain (ie, excluding the SLSS subframe) may be given by (H-DFN * Tmax + DFN).

Hmax, the maximum value of H-DFN, can be configured such that the total number of potential V2V subframes Hmax * Tmax in the hyper DFN range is divided by the configured bitmap length.

33 shows an example of the hyper DFN.

In this example, Hmax may be set to five. (I.e. H-DFN # 5 is reset to H-DFN # 0). In order to support such a hyper DFN, the current H-DFN index needs to be synchronized between the eNB and the terminals as well as the terminals sharing the same resource pool. This may be signaled as part of the resource pool configuration between the eNB and the UE and may also be signaled via the PSBCH. If GNSS is a synchronization reference, the H-DFN index can be derived from the current UTC value.

(C) In conclusion,

Hyper DFN may be proposed as follows to handle the discontinuity of subframe bitmap iteration.

Proposal 1: Hyper DFN can be defined to increase DFN range by Hmax time. The V2V subframe index of the logical domain may be provided by H-DFN incrementing (H-DFN * Tmax + DFN) after a Tmax subframe with H-DFN = 0, 1, ..., Hmax-1. .

Proposal 2: Hmax can be set as the value obtained by dividing Hmax * Tmax by the length of the V2V subframe bitmap of the resource pool.

Proposal 3: The current H-DFN may be signaled as part of the resource pool configuration from the eNB. And may also be signaled via PSBCH.

As another example, in the above example the H _max value may be fixed (on the spec) to a predefined value (without the need for additional signaling). Here, as an example, the H _max value may be fixed to "25" (or "multiple of 25"). Table 4, Table 5, and Table 6 are the analysis data for the above.

TABLE 4

TABLE 5

TABLE 6

As another example, (A) a preset bitmap of (specific) length (/ signaled) is repeatedly applied to specify a V2X resource pool and / or (B) ((terminal) set from a higher layer (/ signaling) When (periodical) transmission resource (s) based on “RESOURCE RESERVATION INTERVAL” are reserved (/ selected), (some) V2X resources and / or (V2X TX UE (S) (Some) (periodic) transmission resources reserved (/ selected) by the DL (time (/ frequency)) resources (e.g., “DL SF” and / or “(TDD) SPECIAL SF) (And / or “DWPTS”)).

Meanwhile, when the UE performs V2X message transmission on a specific carrier, the UE may not perform V2X message transmission using all subframes on the carrier. Accordingly, an example of a method of transmitting a V2X message in consideration of a subframe in which the terminal does not perform a V2X message transmission will be described with reference to the accompanying drawings.

34 is a flowchart of a method of performing V2X communication on an allocated V2X resource pool according to an embodiment of the present invention.

According to FIG. 34, the UE may allocate a V2X resource pool to remaining subframes other than a specific subframe (S3410). In this case, the specific subframe may mean (A) SLSS subframe, (B) TDD shared carrier, DL and S (SPECIAL) subframe, or (C) reserved subframes. Hereinafter, a more specific example of determining a subframe excluded from V2X transmission will be described.

(A) about SLSS subframe,

First, the UE may allocate a V2X resource pool for the remaining subframes other than the SLSS subframe.

Specifically, the SLSS subframe may be excluded from the mapping according to the (repeated) V2V full bitmap (ie, a bitmap (or information) indicating a subframe to which the V2X pool may be allocated), wherein the bitmap The length may mean 16, 20, or 100. The bitmap may define which subframe is a subframe that allows V2V SA and / or data transmission and / or reception. An example in which the SLSS subframe is excluded from the V2X transmission will be described below with reference to the accompanying drawings.

35 schematically illustrates an example in which an SLSS subframe is excluded from a V2X transmission.

In FIG. 35, it is assumed that subframe numbers may have 0, 1, ..., 10239 (that is, 10240 subframes in total), and the V2X bitmap is repeated in units of 10 subframes. It is assumed that the V2X bitmap is [0110101101].

When the UE allocates the V2X logical index, the UE may allocate the V2X logical index to subframes other than the SLSS subframe. For example, when it is assumed that subframe indexes # 3 and # 163 correspond to SLSS subframes (assuming that the SLSS subframes are repeated in units of 160 subframes), the V2X UE is assigned to subframe indexes # 3 and # 163, etc. V2X logical indexes may be allocated to the remaining subframes (that is, the remaining subframes except the SLSS subframe) (S3510). Here, the UE may assume that the V2X resource is allocated according to the V2X bitmap for the subframe allocated by the V2X logical index.

In this case, the V2X logical index derived through the foregoing may not correspond to an integer multiple of the V2X bitmap. For example, when the SLSS subframes are allocated in units of 160 subframes, 64 SLSS subframes may exist in the 10240 subframes as described above, and accordingly, the V2X logical indexes are 10176 corresponding to 10240-64. May be assigned to a subframe.

As such, when a V2X logical index may be allocated to 10176 subframes and 10 V2X bitmap periods are assumed, the logical index and the V2X bitmap period are not divided. That is, when a V2X bitmap having a period of 10 is allocated to 10176 subframes, bits may not be allocated to six subframes.

Accordingly, the UE may exclude the aforementioned number of unassigned subframes from the V2X logical index allocation (S3520). In this case, the unassigned subframes may be evenly distributed (EVENLY DISTRIBUTED).

(B) about DL and S (SPECIAL) subframes,

For TDD (shared) carriers, DL and / or S (SPECIAL) subframes may be excluded from the mapping according to the (repeated) V2V full bitmap. An example in which DL and / or S (SPECIAL) subframes are excluded from V2X transmission will be described below with reference to the accompanying drawings.

FIG. 36 schematically illustrates an example in which DL and S (SPECIAL) subframes are excluded from a V2X transmission.

In FIG. 36, it is assumed that subframe numbers may have 0, 1, ..., 10239 (that is, 10240 subframes in total), and the V2X bitmap is repeated in units of 10 subframes. It is assumed that the V2X bitmap is [0110101101].

When the UE allocates a V2X logical index, the UE may allocate a V2X logical index for subframes other than DL and / or S (SPECIAL) subframes (and / or SLSS subframes). For example, assuming that subframe index # 7 (etc.) corresponds to DL and S (SPECIAL) subframes, the V2X UE may allocate a V2X logical index to the remaining subframes except subframe index # 7 (etc.). It may be (S3610). Here, the UE may allocate V2X resources according to the V2X bitmap for the subframe allocated by the V2X logical index.

Thereafter, the UE may additionally exclude as many subframes as the number not allocated to the V2X logical index allocation (S3520). In this case, the unassigned subframes may be evenly distributed (EVENLY DISTRIBUTED).

(C) for a reserved subframe,

The resource pool is composed of several reserved subframes such that the bitmap is repeated with integers within a specific range (eg, D2D Frame Number (DFN) range). For example, here, the V2X (eg, V2V) logical subframe index may not be assigned to the reserved subframe. In addition, the position of the reserved subframe may be displayed in an implicit manner.

In summary, here, for example, the reason why the problem occurs is the V2X SYNCH (preset (signaled)) bitmap associated with the V2X resource pool configuration. SIGNAL applies without distinction to DL / UL (time / frequency) resources related to WAN communication, except for transmission-related (time (/ frequency)) resources (e.g. V2X SYNCH. SUBFRAME (S)). (And / or because of the DFN WRAP AROUND problem). Here, in one example, to solve the problem, a V2X TX UE (S) (A) (part) V2X resources (specified by the bitmap) on the DL (time (/ frequency)) resources related to WAN communication is Make assumptions that are invalid (in terms of “LOGICAL INDEXING” (in terms of V2X pools)) and / or (B) reserve (by V2X TX UE (S)) on DL (time (/ frequency)) resources related to WAN communication. (/ Selected) (some) (periodic) transmission resources omit the (V2X message (/ TB)) transmission operation (and / or omit the (V2X message (/ TB)) transmission operation and the next (closest) ) Can (re) perform (V2X message (/ TB)) transfer operations on valid (/ available) V2X resources. Here, in one example, in the former case, the "LOGICAL INDEXING" (relative to the V2X pool) includes the invalid resource (eg, DL (time (/ frequency)) resource) (eg, "LOGICAL INDEX"). When the transmission timing of a specific period is determined based on this, it can be interpreted that the actual transmission period can be alleviated (or excluded) due to the problem of (extending) becoming larger than the intended (target) period. In another example, when a predetermined (/ signaled) length bitmap is repeatedly applied, a DL (time (/ frequency)) resource (eg, “DL SF” and / or “WAN communication related resource”) is applied. (TDD) SPECIAL SF ”(and / or“ DWPTS ”) (extra) Exclusion (e.g., that (extra) Excluded resource does not (/ applies)“ LOGICAL INDEXING ”(relative to V2X pool) It may be interpreted that the UL (time (/ frequency)) resources related to WAN communication) may be applied. Here, as an example, the rule may be limitedly applied only under an “IN-COVERAGE” environment (and / or TDD system).

Returning to FIG. 34, the terminal may perform V2X communication on the allocated V2X resource pool (S2420). A specific example of the UE performing V2X communication is as described above.

Here, in one example, the rule may be that a (partial) V2X resource (specified by a bitmap) and / or a (partial) (periodic) transmission resource (reserved / selected) by the V2X TX UE (S) is WAN. Not only is it located on a communication-related DL (time (/ frequency)) resource but also is not suitable for performing (pre-set (/ signaled)) V2X communication (eg, “UL SF” (and / or “UPPTS). Resources other than (time (/ frequency)) resources) (and / or (specific) V2X channel (/ signaling) transmission (/ receiving) resources set to a higher priority than (priority related to V2X messages to be sent)) Extensions can also be applied if

In another example, a V2X UE (S) (in base station coverage) may be configured to pre-define a "offset value for GNSS-based DFN # 0" signaled / set in advance (from a (serving) base station). A channel (eg, PSBCH) may be used to transmit to another V2X UE (S) (out of base station coverage).

As another example, selectable (/ allowable) I_VALUE values and / or “RESOURCE RESERVATION INTERVAL” values on the V2X resource pool (and / or (V2X) carrier) are (“CARRIER (/ POOL)-). SPECIFIC NETWORK (PRE) CONFIGURATION ”), allows the V2X TX UE (S) to: (A) the minimum value of I_VALUE (or I_ MINVAL ) (or on the corresponding V2X resource pool (and / or (V2X) carrier) Maximum value) (or a preset (/ signaled) (specific) I_VALUE value) which can be derived (/ calculated) (e.g. “I_MINVAL * P_STEP”) and / or (B) “RESOURCE RESERVATION INTERVAL ”sensing operation (eg, STEP 5 in Table 2) (and / or based on a minimum (or maximum) period value (or a pre-set (/ signaled) (RESOURCE RESERVATION INTERVAL) value). Energy measurement operation (e.g., STEP 8 of Table 2). Here, as an example, a specific V2X resource pool is set only for P-UE (S) which performs V2X message transmission in a relatively long period (for example, “500MS”) (relative to V-UE (S)). If allowed) and the rule is applied, the P-UE (S) will perform a sensing operation (and / or energy measurement operation) based on the (applicable) period (eg, "500MS").

On the other hand, as described above, the terminal, for example, in a relatively long resource reservation period (for example, 100ms or more resource reservation period) (named as "L_PER") to select a random value in the interval of 5 or more and 15 or less, You can reserve resources by multiplying by 10. However, applying the resource reservation method described above in the case of a relatively short resource reservation period (for example, 20 ms and 50 ms (less than 100 ms) (named “S_PER”) may apply to L_PER coexisting on the same resource pool. The terminal may not be suitable for sensing the S_PER terminal.

Therefore, in order to support (relatively) short period V2X message (/ traffic) transmission, (relatively) “SHORTER RESOURCE RESERVATION PERIOD (/ INTERVAL)” (for example, “20MS”) is introduced. The (some) parameters below can be compared with the case of sending (relatively) V2X messages (/ traffic) in long (relatively) long periods (or previously set (/ signaled) periodic values) (eg “100MS”). Can be set (/ signaled) differently (or independently). Here, in one example, the following (some) parameters are V2X UE (S) (and / or (relatively) of “SHORTER RESOURCE RESERVATION PERIOD (/ INTERVAL)” on (pre-set / signaled) resource pools. V2X UE (S) ( SHORTP _ UE (S) ) which performs short period V2X message (/ traffic) transmission and V2X UE (S) of “(RELATIVELY) LONGER RESOURCE RESERVATION PERIOD (/ INTERVAL)” (and / Or (relatively) V2X UE (S) ( LONGP_UE (S) ) performing long period V2X message (/ traffic) transmission coexists) (A) When SHORTP_UE (S) performs sensing operation and Or (B) LONGP_UE (S) may be interpreted as being applied when performing a sensing operation (for SHORTP_UE (S)). Hereinafter, the method will be described with reference to the drawings.

37 is a flowchart of a method for performing reservation for V2X transmission resources when resource reservation of a relatively short period (eg, 20 ms, 50 ms (less than 100 ms)) is set according to an embodiment of the present invention. .

According to FIG. 37, when a resource reservation of a relatively short period is set, the terminal may perform reservation for a relatively large number of V2X transmission resources (S3710). Here, to reserve a relatively large number of V2X transmission resources, as described above, the terminal does not reserve the resources by multiplying the selected value by multiplying the random value in the interval of 5 or more and 15 or less, 10, This means that a random value is drawn at intervals of 5 * K (where K is a positive integer of 2 or more) and 15 * K or less, and the resource is reserved by multiplying the selected value by 10.

That is, in the case of a relatively short resource reservation period (for example, 20 ms and 50 ms), the above-described counter value (value of 5 or more and 15 or less) is multiplied by, for example, 5 or 2, and then additionally multiplied by 10 to reserve resources. can do.

For example, when the resource reservation period is '20ms', the terminal selects a random value in the interval [5 * 5,15 * 5] (that is, 5 * 2 or more and 15 * 5 or less), and multiplies by an additional 10 You can reserve as many resources. According to the present example, the terminal may reserve more than 250 resources and not more than 750 resources.

As another example, when the resource reservation period is '50ms', the terminal may extract a random value in the interval [5 * 2, 15 * 2], and reserves additional resources multiplied by 10. According to the present example, the terminal may reserve 100 or more resources and 300 or less resources.

(Example # 1) A finite number of subframes (of a resource reservation (interval) period) assumed (/ used) when performing transmission resource (re) reservation (/ selection) and / or C _resel values in Table 2 (e.g. For example, “[10 * SL_RESOURCE_RESELECTION_COUNTER]”)). Here, for example, in case of transmitting (relatively) short period V2X message (/ traffic), the finite number of subframes (and / or C _resel value) (of resource reservation (interval) period) is set relatively small. (/ Signaling) (e.g., has the effect of preventing excessive resource reservation (/ selection) (within a short time period)).

Thereafter, the terminal may perform V2X communication on the reserved V2X transmission resource (S3720). A detailed example of the UE performing V2X communication on the reserved V2X transmission resource is as described above.

38 is a flowchart illustrating a method for performing sensing in a relatively short period when resource reservation of a short period is set according to an embodiment of the present invention.

According to FIG. 38, when a resource reservation of a short period is set, the UE may determine a resource for performing V2X communication by sensing in a relatively short period in the sensing period (S3810). That is, as described above, when the terminal has a resource reservation of a short period is set (for example, resource reservation is set in intervals shorter than 100ms), the sensing (that is, S-RSSI measurement) interval is used for transmission of the terminal The resource reservation interval may be set. In other words, when the terminal is configured for a short period of resource reservation, the terminal may perform the sensing according to the short period used for the resource reservation. This will be described in more detail below.

(Example # 2) V2X message priority (e.g. can be set / signaled to a relatively low (or high) priority) and / or the “PSSCH-RSRP MEASUREMENT” threshold in Table 2 STEP 5 ( And / or “0.2 * M _total ” related coefficient (/ ratio) values in Table 2 STEP 6 (/ 8) (e.g. (in total (candidate) resources) after performing STEP 5 in Table 2 (within the S _A set). The ratio of deriving (/ determining) the minimum number of (candidate) resources that must remain and / or the ratio of deriving (/ determining) the (minimum) (candidate) resource counts that must be in the S _B set after performing STEP 8 in Table 2. May be interpreted as a value (/ signaled) to a different (or independent) value and / or the minimum that must remain in the S _A set (during the entire (candidate) resource) after STEP 5 of Table 2 is performed. (Candidate) “PSSCH-RSRP MEASUREMENT” increase value applied when the number of resources is not met (eg , “3DB”) and / or the periodic value used for the sensing operation (eg STEP 5 in Table 2) and / or the periodic value used for the energy measurement operation (eg STEP 8 in Table 2) For example, in STEP 8 of Table 2, the “100MS” value can be changed (to a relatively short (or long) value))).

(Example # 3) I_VALUE (range) value and / or P_STEP value selectable (/ allowed) on the V2X resource pool (and / or (V2X) carrier).

(Example # 4) Transmission power related (OPEN-LOOP) parameters (/ values) (eg “P _O “, “ALPHA”, etc.) and / or V2X resource pools (/ carriers).

As another example, the V2X UE (S) may perform (transmission) resource (re) selection as follows.

The V2X terminal may select a transmission resource in the following manner.

It is assumed that the terminal selects resources by itself. Under the above mode, when the resource selection / reselection for V2X message transmission is triggered, the terminal performs sensing and selects / reselects a resource based on the sensing. The terminal may transmit a scheduling assignment (SA) indicating the selected / reselected resource.

For example, resource selection / reselection may be triggered to the UE in subframe # (also referred to as TTI, hereinafter same) #n. Then, the terminal performs sensing between the subframe #na and the subframe #nb (a> b> 0, where a and b are integers), and selects a resource for V2X message transmission based on the result. Can be reselected.

The a and b may be values that are set in common to the V2X terminals, or may be values that are set independently for each V2X terminals.

Alternatively, when the above-described a and b values are common to V2X terminals, they may be in a relationship such as 'a = 1000 + b'. That is, if the UE is triggered to select a resource for V2X message transmission by itself, the UE may perform a sensing operation for one second (1000 ms = 1000 subframes = 1000 TTIs).

The UE may consider all of the decoded SA transmissions in the period from subframe # n-a to subframe # n-b. The decoded SA may be related to data transmission in a period from subframe # n-a to subframe # n-b, and the decoded SA may be considered to be transmitted before subframe # n-a.

The UE that fails to perform the sensing operation in subframe #m (for example, due to need to transmit a signal in subframe #m) selects subframes # (m + 100 * k) in resource selection / reselection. Can be excluded. Meanwhile, the UE may skip without performing a sensing operation in subframes used to transmit a signal.

After performing the sensing, the terminal selects a time / frequency resource for the PSSCH, that is, the sidelink data channel.

The UE may transmit a scheduling assignment (SA) in subframe # n + c. C is an integer greater than or equal to 0, and may be a fixed value or a variable. The UE may not require scheduling allocation transmission (ie, PSCCH transmission) in subframes whose c value is less than c _min . The c _min may be a fixed value or a value set by a network.

The scheduling assignment SA transmitted in subframe # n + c may indicate associated data transmitted in subframe # n + d. d may be an integer greater than or equal to c (d ≧ c). c and d may both be values of 100 or less.

Meanwhile, if any one of the following conditions is satisfied, reselection of V2X resources may be triggered.

(A) The counter satisfies the expiration condition.

The counter is decremented every transmission block transmission, and may be reset if reselection is triggered for all semi-statically selected resources. The value to be reset can be chosen randomly with equal probability between a certain range, for example between 5 and 15.

(B) The transport block does not match the current resource allocation even when the maximum allowed modulation and coding scheme (MCS) is used.

(C) The case is indicated by a higher layer.

Meanwhile, when all PSCCH / PSSCH transmissions have the same priority, selection / reselection of PSSCH resources may be selected through the following process.

(A) STEP 1:

Once all resources are considered selectable,

(B) STEP 2:

Scheduling allocation decoding and excluding certain resources based on additional conditions. In this case, the terminal may select one of the following two options.

The first option is to exclude those resources indicated or reserved (reserved) by the decoded scheduling assignment and resources whose DM-RS power is received above the threshold in data resources associated with the scheduling assignment.

The second option is to exclude those resources indicated or reserved by the decoded scheduling assignment and those whose energy measured at the data resources associated with the scheduling assignment is above a threshold.

(C) STEP 3:

The terminal may select a V2X transmission resource among the resources that are not excluded.

For example, the UE may select and subset the PSSCH resources after the remaining PSSCH resources are measured and ranked based on the total received energy. The terminal compares the energy in the currently selected resources with the energy in the subset, and if the energy in the currently selected resources is greater than a threshold relative to the energy in the subset, may select one of the subsets. . The terminal may randomly select one resource from the subset.

Or, the UE can select and subset after measuring and ranking the remaining PSSCH resources based on the total received energy. The terminal may randomly select one resource from the subset.

Or, the UE can select and subset after measuring and ranking the remaining PSSCH resources based on the total received energy. The terminal may select a resource that minimizes fragmentation of frequency resources in the subset.

For example, when the (transmission) resource (re) selection operation is performed according to Table 2, the following (some) rules may be additionally applied.

[Suggested Rule # 10] As an example, depending on the 'LATENCY (/ QOS) REQUIREMENT' (and / or 'PRIORITY' and / or 'SERVICE TYPE') of the packet (to be sent or generated), the '(D (/ C ) -M) '((max (/ min))) range (for example, can be interpreted as' TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW)') (for example, the value 'M' The point at which a packet (to be sent or generated) (/ message) arrives on (or receives) a (LOW LAYER) buffer (and / or 'PDCP LAYER') (or when a packet (/ message) is generated). Also, (where) 'D (/ C)' wording is (exceptionally) (initially) after the resource (re) selection (/ reservation) action is triggered (e.g. SUBFRAME # N) ) The data (PSSCH) (which may be interpreted as the transmission time / control information (PSCCH)) may be set (/ signaled) differently. As another example, the value 'C' and / or 'D' ((maximum (/ min))) range (for example, can be interpreted as 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW)') Should be determined to satisfy (or consider) the 'LATENCY (/ QOS) REQUIREMENT', which may differ depending on the 'SERVICE TYPE' (and / or 'PRIORITY LEVEL'). Here, as an example, 'UPPER LIMIT (/ LOWER BOUND)' of 'C' and / or 'D' values (for example, can be interpreted as 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW)') It may not be fixed. Here, as an example, the 'UPPER LIMIT (/ LOWER BOUND)' may be set (/ signaled) differently according to 'PRIORITY LEVEL' (and / or 'SERVICE TYPE' and / or 'LATENCY (/ QOS) REQUIREMENT'). Can be. Here, for example, if the currently selected 'D' value (or 'SUBFRAME # D') satisfies the 'LATENCY (/ QOS) REQUIREMENT' of a newly arrived (/ generated) packet (/ message). If present, the (transmit) resource (re) selection operation may be triggered. Here, as an example, the maximum (and / or minimum) or range (eg 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW))' of the value 'D' (and / or 'C') is interpreted. Possible) is the time (or packet (/ message)) at which a packet (/ message) arrives (or receives) (or transmitted) on a 'LOW LAYER) buffer' (and / or 'PDCP LAYER'). Point in time ('M') and / or (where the predefined (/ signaling) condition is met) (point at which the (transfer) resource (re) selection action is triggered ('N') and / or 'LATENCY REQUIREMENT' ( 'L') (e.g. '100MS') and / or 'part of PPPP' (e.g.) different (partly) by 'PPPP' (e.g. different 'LATENCY REQUIREMENT' packets Can be determined in consideration of the setting (if allowed). Here, as a specific example, the maximum value (and / or minimum value) of the value 'D' (and / or 'C') is determined as '(L-ABS (MN))' or 'MIN (L, (L'). ABS (MN))) '(where, for example,' MIN (X, Y) 'and' ABS (Z) 'are functions that derive the minimum value among' X 'and' Y ', respectively, the absolute value of' Z ' Value, or 'D' (and / or 'C') ranges from '(L-ABS (MN)) <D (/ C) <100 (/' LATENCY REQUIREMENT ')' (or '(L-ABS (MN)) ≤ D (/ C) ≤ 100 (/' LATENCY REQUIREMENT ')'). Here, as an example, the maximum (and / or minimum) value of the 'D' (and / or 'C') value is calculated (/ determined), taking into account the retransmission of a particular (one) 'TB (/ packet / message)'. ), You may need to subtract the predefined 'MARGIN (/ OFFSET)' value (' MAG_VAL ') from the 'L' value. Here, for example, when the rule is applied, the maximum value (and / or minimum value) of the value 'D' (and / or 'C') is' ((L-MAG_VAL)-ABS (MN)) 'or' MIN ((L-MAG_VAL), ((L-MAG_VAL)-ABS (MN))) '. Here, as an example, the 'MAG_VAL' value may have 'DEPENDENCY' (for example, the 'MAG_VAL' value increases as the number of retransmissions increases). Here, as an example, the rule may be triggered by a '(transmit) resource (re) selection operation' triggered (as a pre-defined (/ signaled) condition is met)) and the '(LOW LAYER) buffer' (and / or It may be limitedly applied only when there is a packet (/ message) (or transmitted / generated) on PDCP LAYER (or when a packet (/ message) is generated). Here, as another example, '(transfer) resource (re) select operation' was triggered (as the predefined (/ signaled) condition is met)) '(LOW LAYER) buffer' (and / or ' PDCP LAYER ') (when there is no packet (/ message) to be sent or generated) (or no packet (/ message) generated),' (N = M) '(e.g. ( Transmit) A packet (/ message) (to be sent or created) is received on the '(LOW LAYER) buffer' (and / or 'PDCP LAYER') at the time ('N') when the resource (re) selection operation is triggered. Can be interpreted as assuming (/ referring) to the point of time ('M'), or (transfer) resource (re) selection operation is performed by '(LOW LAYER) buffer' (and / or Postpone until a packet (to be sent or generated) on (PDCP LAYER) is actually arriving (/ received) (or actually a packet (/ message) is generated), or ('N' time point) Including (or po (Previously) assume that a packet (/ sent) (to be sent or generated) has arrived (/ received) on the '(LOW LAYER) buffer' (and / or 'PDCP LAYER') ( Or, it may be assumed that a packet (/ message) is generated) and perform a (transmission) resource (re) selection operation. As another example, the maximum value of the 'D' (and / or 'C') value (described above) (eg, '(L-ABS (MN))', '100 (/' LATENCY REQUIREMENT ')' Subsequent resources, including (or not including) time points corresponding to), are assumed to be unavailable and excluded (from (re) selectable candidate resources (on 'STEP 3 (/ 2)')). You can do that. As a further example, the 'C' (and / or 'D') value (e.g., the 'C' time point is the (first) control (/ after the (transmit) resource (re) selection action is triggered ('N'). Scheduling) The minimum value ( C_MIN ) (for example, 'minimum value') of the information (PSCCH) which can be interpreted as the time point at which transmission is performed is determined in consideration of the 'PROCESSING TIME' of the terminal (for example, '4MS'). Between previous resources (or 'N' and '(C + C_MIN)'), including (or not) the time point corresponding to the point in time (eg '(C + C_MIN)') Resources (where, for example, resources that may be included (or may not be included) at the time of 'N' and '(C + C_MIN)') are assumed to be unavailable (/ regarded) (( May be excluded (in re-selectable candidate resources) on 'STEP 2 (/ 3)'. As another example, according to the (some) proposal rule described in the present invention (for example, [suggest rule # 1], [suggest rule # 10], etc.), 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW) ) '((Maximum value (/ minimum value)) range) may be set (/ changed) differently in consideration of' PRIORITY LEVEL '(and / or' SERVICE TYPE 'and / or' LATENCY (/ QOS) REQUIREMENT '). In this case, depending on whether a predefined condition is satisfied, the following (partial) parameters related to the sensing operation (and / or (transmission) resource (re) selection (/ reservation) operation (and / or V2X message transmission)) are different. It can also be specified. Here, as an example, the (applicable) condition is (A) when transmitting a V2X message of 'LATENCY REQUIREMENT' shorter (or longer) than a preset (/ signaled) threshold (and / or pre-set (/ signaling). In case of sending a V2X message of 'PPPP' higher (or lower) than the threshold, and / or (B) in the 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW)' (And / or) if there are fewer (or more) (selectable) (candidate) resources (e.g. subframes) than (signaled) thresholds (and / or 'TX RESOURCE (RE) SELECTION DURATION ( / RANGE / WINDOW) 'may be defined as the minimum value (/ maximum value) is smaller (or larger) than a preset (/ signaled) threshold.

(Example # 10-1) PPPP value (/ range) (for V2X message) For example, for a V2X message with 'LATENCY REQUIREMENT' short (or longer) than (pre-set (/ signaled) threshold) In this case, the transmission may be protected by selecting a relatively high (or low) PPPP value (/ range), where, for example, a transmission based on a high (or low) PPPP value (/ range) may be performed by another terminal. This means that when determining whether the resource being used for this transmission is selectable (or IDLE / BUSY), it is determined by the relatively low (or high) PSSCH-RSRP threshold.) (And / or the PPPP value (/ V2X of 'LATENCY REQUIREMENT' long (or shorter) than the PSSCH-RSRP threshold (e.g., the same PPPP value (/ range)) associated with the range) (e.g., than the preset (/ signaled) threshold) For messages, by setting (/ signaling) a relatively low (or high) PSSCH-RSRP threshold, Protects the transmission of V2X messages with 'LATENCY REQUIREMENT' short (or longer) than the (/ signaled) threshold.) And / or the interval (/ period) and / or the candidate (transmit) resource. Selectable ((max / min)) section (/ range) (/ SELECTTION WINDOW) and / or (re) selected (or reserved) range to select a random value (or draw) (And / or coefficients multiplied by the corresponding random value (to derive the C_RESEL value [1/2/3])) and / or the candidate (transmit) resource exclusion based on the resource reservation period and / or the PSSCH-RSRP threshold. After operation, if the candidate (transmit) resource rate (/ count) that should remain at a minimum (and / or the corresponding candidate (transmit) resource rate (/ count)) is less than the preset (/ signaled) threshold, then ( The offset value added to the PSSCH-RSRP threshold) and / or the S-RSSI After a candidate (transmit) resource exclusion operation of a candidate (transmit) resource ratio (/ count) that should remain at a minimum (for example, shorter (or longer) than the preset (/ signaled) threshold) REQUIREMENT's V2X message (and / or transmits a V2X message of 'PPPP' higher (or lower) than the (pre-set (/ signaled) threshold) and / or 'TX RESOURCE (RE) SELECTION DURATION (/ RANGE / WINDOW) ', where there are fewer (or more) (selectable) (candidate) resources than (/ remaining) preset thresholds (/ signaled) and / or' TX RESOURCE ( RE) SELECTTION DURATION (/ RANGE / WINDOW) 's minimum (/ maximum) value is smaller (or larger) than the preset (/ signaled) threshold, (A) PSSCH-RSRP threshold based candidate ( (Transmit) resource ratio (/ count) and / or (B) that should remain at a minimum after the transmit) resource exclusion operation If the remaining candidate (transmit) resource ratio (/ count) is less than the preset (/ signaled) threshold, an offset value added to the (related) PSSCH-RSRP threshold and / or (C) the S-RSSI based After a candidate (transmit) resource exclusion operation, the ratio of candidate (transmit) resources (/ count) that should be kept to a minimum may be specified relatively high (eg, collision probability increase mitigation effect) and / or CBR thresholds used in (sub) channel BUSY (/ IDLE) determination and / or allowed (/ limited) RADIO-LAYER PARAMETER SET (e.g. maximum transmit power, retransmission count per TB) (/ Range), MCS value (/ range), maximum limit of OCCUPANCY RATIO (CR_LIMIT), etc.) [1/2/3])

[Proposed Rule # 11] As an example, '(TIMER) EXPIRATION CONDITION' relating to (transmission) resource (re) selection may be defined when the following (some) conditions are met (simultaneously). Here, in one example, the V2X UE (s) causes (actually) (assuming (transmit) resource (re) selection operation has been triggered) only when (sometimes) the following (some) conditions are satisfied (simultaneously): Transmit) resource (re) selection operation.

(Example # 11-1) When the counter value (decremented by a preset value (for example '1') for every TB transmission) is changed to '0' (and / or 'negative value')

(Example # 11-2) If there is a packet (/ message) (sent or created (/ received)) on '(LOW LAYER) Buffer' (and / or 'PDCP LAYER') (and / or packet ( / Messages)

[Suggested Rule # 12] As an example, the counter value (which is decremented by a preset value (e.g., '1') for every TB transmission) is changed to 'EXPIRATION CONDITION' (eg, the counter value is '0' ( And / or changed to 'negative value') (and / or '(transmitted) resource (re) select action' was triggered (as a pre-defined (/ signaled) condition is met)). If there are no packets (/ messages) to be sent or created (/ messages) on the (LOW LAYER) buffer (and / or 'PDCP LAYER') (or if no packets (/ messages) were created) ), Assuming that the V2X UE (s) reaches (/ generates) the (most recent) packet (/ message) to 'INTERVAL (/ PERIODICITY)' observed previously (/ recent), ( (Transfer) If the resource (re) selected and then (after) actually encounters a problem (for example, does not satisfy 'LATENCY (/ QOS) REQUIREMENT' with the (re) selected (transfer) resource), It may be possible to additionally perform a raw (re) selection operation.

In one example, according to the following method (in addition to the rules described in Table 2), the V2X UE (S) may be allowed to perform (transmit) resource (re) reservation.

d may be a value less than or equal to d _max . d _max may be determined depending on the priority (priority) such as the terminal / data / service type.

The UE may inform whether to reuse frequency resources for signals transmitted in subframe # n + d for potential transmission of other transport blocks in subframe # n + e. Here, e is an integer and has a relationship of d <e. The terminal may explicitly or implicitly inform the reuse. The e value may be one value or a plurality of values. In addition, after subframe # n + e, it may be informed that frequency resources for signals transmitted in subframe # n + d are not used.

The receiving terminal receiving the V2X signal decodes the scheduling assignment (SA) transmitted by the transmitting terminal transmitting the V2X signal. In this case, it may be assumed that the same frequency resource is reserved in subframe # n + d + P * j (j = i, 2 * i, ..., J * i) by the scheduling assignment. P may be 100. The J value may be explicitly signaled by the scheduling assignment or may be a fixed value (eg, 1). The i value may be explicitly signaled by the scheduling assignment, or may be a preset value or a fixed value. Alternatively, the i value may be an integer between 0 and 10.

[Proposed Rule # 13] As an example, by causing the V2X TX UE (s) to signal a “I” value (see I described above) through an SA (field), the V2X RX UE (s) is connected to a V2X TX UE ( S) knows at what point in the future (in addition) to (additionally) reserve (/ use) the same frequency resource specified (/ scheduled) via SA (for example, a V2X TX UE sets the “I” value to “2”). When signaled with V2X RX UE (S), the same frequency assigned (/ scheduled) via SA (applicable) on “TTI # (N + D)”, “TTI # (N + D + 2 * P)” The resource is assumed to be reserved). Here, as an example, hereinafter, for convenience of explanation, the value “I” is set in advance (/ signaled) “[0, 1,... , 10] ”is assumed to be selected (4 bits) and / or the value of“ J ”(see J above) is fixed to“ 1 ”. Here, as an example, the V2X MESSAGE generation period is changed according to a predefined parameter (for example, speed / (going) direction change amount, etc.), so that the V2X TX UE (S) generates a (own) V2X MESSAGE generation period. If it is difficult to predict accurately, it may not be efficient to reserve (future) resources according to the above method. Here, as an example, as a way to solve the problem, the V2X RX UE (S), if a particular V2X TX UE (S) signaled the "I" value (on the SA field) to "2"" The same frequency resource ( HARD_RSC ) assigned (/ scheduled) via SA (on the corresponding T) in TTI # (N + D) ”,“ TTI # (N + D + 2 * P) ”is called“ EXPLICIT ”(or HARD). Suppose it is reserved, but based on the remaining “I” value (not signaled via SA (field)) (eg “TTI # (N + D + 1 * P)”, “TTI # (N + D) + 3 * P) ”,“ TTI # (N + D + 4 * P) ”,“ TTI # (N + D + 5 * P) ”,“ TTI # (N + D + 6 * P) ”,“ TTI # (N + D + 7 * P) ”,“ TTI # (N + D + 8 * P) ”,“ TTI # (N + D + 9 * P) ”,“ TTI # (N + D + 10 * P) ”) on the same frequency resource ( SOFT_RSC ) (designated (/ scheduled) via SA) can be assumed to be reserved for“ POTENTIAL (or SOFT). ”Here, for example, the rule (And / or SOFT_RSC reservations) are pre-set (/ signaled) features Only applicable to RESOURCE ALLOCATION MODE (e.g., RANDOM RESOURCE SELECTION of MODE 1 and / or P-UE (not applicable to RESOURCE SELECTION based on / PARTIAL SENSING)). If this is applied, the V2X TX UE (S) may select a candidate according to the “DM-RS POWER / ENERGY MEASUREMENT” value for HARD_RSC and SOFT_RSC of another V2X TX UE (S) (determined based on SA decoding). In determining whether a resource is a resource or a resource to be excluded (Step 2 in Table 2), a different preset (DM-RS POWER / ENERGY MEASUREMENT) threshold may be applied. HARD_RSC related threshold ( HARD_ TH ) is set lower than (or higher than) SOFT_RSC ( SOFT_ TH ) (/ signaling) (e.g., HARD_RSC can be interpreted to be protected with a higher priority than SOFT_RSC). Can be). Here, as an example, SOFT_RSC relevant threshold is set to form an offset value (HARD_ THOFF) about the HARD_RSC (/ signaling) (and / or HARD_TH relevant threshold is set to the offset value (SOFT_ THOFF) form about a SOFT_RSC ( / Signaling)). Here, as an example, (A) when the HARD_THOFF value is set (/ signaled), another V2X TX UE (S) sets the HARD_RSC and SOFT_RSC (of the corresponding V2X TX UE (S)) to the same priority as “DM”. -RS POWER / ENERGY MEASUREMENT ”value to determine exclusion (Step 2 of Table 2) (or (applicable) V2X TX UE (S) is to determine the ((applicable) SA on the point of time based on all“ I ”values). And (B) if the HARD_THOFF value is set (/ signaled) to “infinity (or relatively large)”, another V2X TX UE (S ) Determines SOFT_RSC (of the corresponding V2X TX UE (S)) as a selectable candidate resource (or a very high probability) at all times (Step 2 of Table 2). Here, as an example, (A) V2X MESSAGE PRIORITY (and / or V2X MESSAGE PRIORITY to be transmitted by the other V2X TX UE (S) identified based on SA decoding) and / or (B) (measured) “CONGESTION LEVEL Different thresholds (e.g., HARD_TH, SOFT_TH) (or offset values (e.g., HARD_THOFF (or SOFT_THOFF))) are set differently (/ signaling) (and / or (C) based on SA decoding. According to the V2X MESSAGE PRIORITY (and / or the V2X MESSAGE PRIORITY you wish to transmit) and / or (D) the (measured) “CONGESTION LEVEL” of the other V2X TX UE (S) identified by the For example, HARD_TH, SOFT_TH) (or an offset value (eg, HARD_THOFF (or SOFT_THOFF))) may be adjusted. Here, as an example, the V2X TX UE (S) is set in advance to the (DM-RS POWER / ENERGY MEASUREMENT) value associated with the HARD_RSC and SOFT_RSC of the other V2X TX UE (S determined based on the SA decoding) (/ signaling The different offset values may be applied to determine whether the candidate resource is a selectable resource or a resource to be excluded (Step 2 of Table 2). Here, as an example, the HARD_RSC related offset value (eg, assumed to be “negative value”) is set larger (or smaller) than that of SOFT_RSC (/ signaling) (eg, HARD_RSC is relatively higher than SOFT_RSC). May be interpreted as being protected by priority). Here, as an example, only an offset value for the “DM-RS POWER / ENERGY MEASUREMENT” value related to SOFT_RSC (or HARD_RS) may be set (/ signaled). Here, as an example, (A) V2X MESSAGE PRIORITY (and / or V2X MESSAGE PRIORITY to be transmitted by the other V2X TX UE (S) identified based on SA decoding) and / or (B) (measured) “CONGESTION LEVEL V2X MESSAGE PRIORITY (and / or V2X MESSAGE PRIORITY of other V2X TX UE (S) identified based on (/ signaling) (and / or (C) SA decoding) ) And / or (D) the (measured) offset value may be adjusted depending on the (measured) “CONGESTION LEVEL”. Here, as an example, when the V2X TX UE (S) selects (reserves) SA TX related resources, it is linked with data transmission (s) on HARD_RSC and SOFT_RSC of another V2X TX UE (S) (determined based on SA decoding). For the SA transmission resource (s), it is a (SA) candidate resource that is selectable by applying different “DM-RS POWER / ENERGY MEASUREMENT” thresholds (or offset values) that have been (preferably) pre-set (/ signaled). You may want to determine if it is a resource to be excluded. Here, as an example, (A) the "TIME GAP" (range) value between the SA transmission time and the interworking data transmission time is different depending on which resource type (eg, HARD_RSC, SOFT_RSC) the data is transmitted. Configuration (/ signaling) and / or (B) different (or independent) (transmit) power values (/ (transmission) power control parameters) (and / or (maximum permissible) MCS values) associated with data transmitted over different resource types. It can also be set (/ signaling). In one example, the V2X message transmission period (eg, “1000MS”) of the PEDESTRIAN UE ( P- UE ) is that of the VEHICLE UE ( V- UE ) (when considering the relatively slow travel speed and / or the need for battery saving). It can be set (/ signaled) relatively long compared to (eg, “100MS”). Here, for example, when the P-UE transmits a V2X message, the “I” value on the SA field points to a specific value (or “RESERVED STATE”) that has been previously set (/ signaled), so that another V2X RX UE ( S) allows (A) (applicable) SA (and / or interlocked data) transmissions to be interpreted as being performed by the P-UE and / or (B) (scheduled) SA-based (scheduled) resources It can be interpreted as being reserved at a predetermined (/ signaled) (relatively long) period (relative to V-UE).

[Suggested Rule # 14] As an example, V2X TX UE (S) allows (A) if multiple (SIDELINK ( SL )) SPS PROCESS (/ CONFIGURATION) are simultaneously associated with different service types and / or V2X MESSAGE PRIORITY. If you were operating (or activating), when selecting a specific (SL) SPS PROCESS (/ CONFIGURATION) related transport resource, another (SL) SPS PROCESS (/ CONFIGURATION) related resource selected previously (or already) May be interpreted as a (selectable) candidate resource (STEP 2 in Table 2) and / or (B) a pre-set (/ signaled) synchronization signal (PRIMARY SIDELINK SYNCHRONIZATION SIGNAL ( PSSS )). / SECONDARY SIDELINK SYNCHRONIZATION SIGNAL ( SSSS )) (and / or PHYSICAL SIDELINK BROADCAST CHANNEL ( PSBCH )) Transmit (time (/ frequency)) resources (e.g., "subframes") are excluded from the (selectable) candidate resources. Can be defined (Step 2 of Table 2) .

[Suggested Rule # 15] As an example, when a V2X (TB) transmission operation is omitted at a specific time point according to a preset (/ signaled) “(DROPPING) PRIORITY” (for example, “WAN UL TX ( S) ”(and / or“ Synchronous Signal Transmission (Resource) ”) and V2X (MESSAGE) TX (S) overlap (some or all) in the time (/ frequency) domain, resource reselection counters (Table 2 ) Value can be defined to decrement (and / or define to trigger a resource reselection action). For example, define a V2X TX UE (S) to trigger a resource reselection operation when its “SYNCHRONIZATION SOURCE” changes (and / or change the “SYNCHRONIZATION SOURCE” related time (/ frequency) synchronization value and the existing “ SYNCHRONIZATION SOURCE ”can be defined to trigger the resource reselection operation only if the difference between the (time (/ frequency) synchronization) values is greater than the preset (/ signaled) (maximum allowed) threshold. For example, if V2X TX UE (S) changes its "SYNCHRONIZATION SOURCE", (A) (if the remaining "LATENCY" value is less than the preset (/ signaled) threshold) transmission resources Define for random selection (/ reservation) (e.g., randomly selected resources should only be used for transmission of a preset (/ signaling) number of "TRANSPORT BLOCK ( TB )", and then sensing-based selection (/ reservation) And / or (B) select a transmission resource (/ reserve) after performing a sensing operation during a pre-set (/ signaled) time period. It can be defined to. Here, as an example, a V2X TX UE (S) may cause a plurality of (other) “SYNCHRONIZATION SOURCE” related communications (including the current “SYNCHRONIZATION SOURCE”) (based on a preset (/ signaled) value). If the SYNCHRONIZATION SOURCE is changed to one of them, the sensing result value (related to the changed SYNCHRONIZATION SOURCE) may be used to select (/ reserve) a transmission resource.

[Proposed Rule # 16] In one example, a V2X UE (S) may be configured to (A) pre-set (/ signal) the same (or (time (/ frequency))) synchronization difference with the same (or (time (/ frequency))) synchronization. Define to report how many carriers are capable of simultaneous receive (/ transmit) less than the threshold and / or (time (/ frequency)) synchronization differences with different (or (time (frequency))) synchronization It can be defined to report (independently) how many carriers are capable of simultaneous reception (/ transmission) for how many carriers greater than the set (/ signaled) threshold. Here, as an example, the (serving) base station that has received such (capability) information sets the appropriate number of carriers for V2X communication (receive / transmit) in consideration of the capability of the V2X UE (S). / Signaling). In one example, for MODE 1 V2X communication, the (serving) base station may determine different MCS (range) values according to the absolute speed of the V2X UE (S) and / or “SYNCHRONIZATION SOURCE TYPE (eg, GNSS, ENB)” and The relevant information may be signaled (to the V2X UE (S)) so that the V2X TX operation of the number of RESOURCE BLOCKs (RBs) and / or the number of (HARQ) retransmissions is performed. In one example, the (serving) base station may adjust the “location based pool size” based on the speed (/ location) information reported from the V2X UE (S) (in its coverage). Here, as an example, the (serving) base station sets (/ signals) the “location based pool size” information for each speed (range) to the V2X UE S (in its own coverage), and the V2X UE S It is possible to apply (/ use) "location based pool size" information corresponding to its speed to perform V2X communication.

[Suggested Rule # 17] As an example, ((A) HARQ COMBINING operation for receiving different REDUNDANCY VERSION ( RV ) (data) reception and / or (B) (time) resource location information signaling related to data (re) transmission set to cause the PSCCH payload size (increase) in consideration of a), V2X TX UE (S) is required, the data (re) transmission-related time resources to advance for a specific (single) TB associated plurality (NUM _ RETX) ( / Signaled ) can be selected within the interval ( LIM _ TIMEWIN ). Here, as an example, when the corresponding rule is applied, let the V2X TX UE (S) operate the sensing-based resource (re) selection (eg, STEP 2/3 in Table 2) according to the following (some) method. Can be done. Here, in one example, the LIM_TIMEWIN value is (A) V2X MESSAGE PRIORITY which V2X TX UE (S) wants to transmit and / or (B) (measured) CONGESTION LEVEL and / or (C) V2X MESSAGE (/ SERVICE) related TARGET LATENCY (/ RELIABILITY) It can be adjusted (or set differently) depending on the REQUIREMENT etc.

(Example # 17-1) As an example, (Table 2) NUM_RETX (relative to a specific TB) of (non-excluded) resources ( NOEX _RSC ) derived as a result of performing STEP 2 (eg, OPTION 2-1). If no (re) transmission time resources related to data (re) transmission can be selected (all) in LIM_TIMEWIN (or if the number of candidates that can be selected in LIM_TIMEWIN is smaller than a preset (/ signaled) threshold), (A) (specific) TB-related) (NUM) RETX data (re) transmissions are defined to omit (all) and / or (B) only (maximum) time resources selectable within LIM_TIMEWIN (specific TB-related) data (re) Interval value ( FLIM _ TIMEWIN ) that is defined to perform (partially) and / or (C) (used / applied) in this case (eg, FLIM_TIMEWIN ) (eg, “FLIM_TIMEWIN” > LIM_TIMEWIN ”) before NUM_RETX data (re) PSSCH DM-RS RSRP is defined to select relevant time resources (eg omit if there are no selectable candidates in FLIM_TIMEWIN) and / or (D) (Table 2) STEP 2 (regarding resource exclusion) The number of candidates that can be selected in the LIM_TIMEWIN (or LIM_TIMEWIN) is set in advance until the THRESHOLD value can be selected (all) within the NUM_RETX data (re) transmission-related (re) transmission of the (specific TB). Up to a greater than / signaled threshold value), by an offset value previously set (/ signaled). For example, (in accordance with the above rules) (Table 2) after STEP 2 is performed) (Table 2) PSSCH DM-RS RSRP value of the lower (or higher) X% on STEP 3 is measured (specific TB related) When selecting NUM_RETX data (re) transmission related time resources according to a predefined rule (e.g. random selection method), if the selected (some) time resources are not present in LIM_TIMEWIN (or FLIM_TIMEWIN) Or (B) defined to perform reselection (until that condition is met) and / or (B) defined to omit (all) NUM_RETX data (re) transfers (all). C) Can be defined to perform (partly) data (re) transmission (particularly TB-specific) using only time resources located within the LIM_TIMEWIN (or FLIM_TIMEWIN).

[Suggested Rule # 18] As an example, the CYCLIC SHIFT ( CS ) (and / or OCC) value for PSCCH DM-RS may be a predefined (/ signaled) (specific) value (eg, “CS INDEX = 0”). , “OCC = [+1 +1]”). Here, as an example, when the corresponding rule is applied, when (partly) PSCCH transmission resources overlap between different V2X TX UEs (S), a problem arises in that PSCCH-related reception performance cannot be guaranteed. Here, as an example, in order to alleviate the problem, the V2X TX UE (S) may be configured to define a predefined rule (eg, in a pre-set (/ signaled) CS SET (and / or OCC SET). It is possible to select a (one) CS (and / or OCC) value according to the random selection method). Here, as an example, the CS (INDEX) SET may be set (/ signaling) to " CS INDEX 0, 3, 6, 9". Here, in one example, the V2X RX UE (S) is (all) CS (and / or OCC) in the corresponding CS SET (and / or OCC SET) (because it does not know exactly which value the V2X TX UE (S) chose). It performs a blind detection ( BD ) operation for. Here, as an example, the CS (and / or OCC) value that the V2X TX UE (S) selects in the CS SET (and / or OCC SET) is (A) (V2V) subframe (/ slot) index and / Or (B) a V2X TX UE ID (or (TARGET) V2X RX UE ID) and / or (C) an ID (x bit) transmitted on the PSCCH as an input parameter (/ seed value) Is defined to be randomized (or hopped) by the (and / or the CS SET (and / or OCC SET) (configuration) of the V2X TX UE (S) is (D) (V2V) subframe (/ slot) index and / Or (E) a V2X TX UE ID (or (TARGET) V2X RX UE ID) and / or (F) an ID (x bit) transmitted on the PSCCH as an input parameter (/ seed value) ) Can be defined to be randomized (or changed). Here, as an example, the CS SET (and / or OCC SET) (configuration) is set differently according to the V2X MESSAGE PRIORITY (to be transmitted by the V2X TX UE (S)) and / or the (measured) CONGESTION LEVEL, etc. Can be Here, as an example, in order to reduce the complexity associated with (PSCCH DM-RS) CS (and / or OCC) BD operation of the V2X RX UE (S) (when the above rule is applied), one sub (from (serving) base station) The maximum number of BDs to be performed (by the V2X RX UE (S)) within a frame may be set (/ signaled). Here, as an example, the V2X UE (S) may allow the BD number information that it can perform to the maximum in one subframe through the predefined signaling (to the (serving) base station) through the predefined signaling. . Here, in one example, the PSCCH SCRAMBLING SEQUENCE GENERATOR (all) CS (and / or OCC) in the CS SET (and / or OCC SET) (pre-set (/ signaled)) that the V2X TX UE (S) selects. It can be initialized according to a value (and / or a pre-set (/ signaled) C_INIT value (eg “510”)). Here, as an example, a CS field (eg, “3 bits”) may be defined on the PSCCH (when applicable rule is applied), and the corresponding CS field value is previously set by the V2X TX UE (S) (/ Predefined with an input parameter (and / or SELCS_VAL value) by the selected (one) CS value ( SELCS _VAL ) according to a predefined rule (e.g. random selection method) within the signaled CS SET PSSCH DM-RS CS (in conjunction with PSCCH) according to the corresponding (specified) CS field value, by means of derived (/ calculated) values based on randomized (randomized / hopping) functions The value can be set (/ determined). Here, as an example, if the rule is applied, if the interference on the PSCCH DM-RS (CS) has been mitigated (/ randomized), the interference on the (interlocked) PSSCH DM-RS (CS) (same) is also mitigated (/ Randomized). Here, as an example, here, as an example, the PSSCH DM-RS CS value (in conjunction with the PSCCH) (when the rule is applied) does not further define a CS field (eg, “3 bits”) on the PSCCH. (One) PSCCH DM-RS CS value (SELCS_VAL) selected according to a predefined rule (e.g. random selection method) within a CS SET that V2X TX UE (S) is pre-set (/ signaled) ) And / or (same) by a derivation (/ calculation) value based on a predefined (randomized (/ hopping)) function having an SELCS_VAL value as an input parameter. Here, in one example, the PSSCH SCRAMBLING SEQUENCE GENERATOR sets the CS field value (on the PSCCH) and / or the V2X TX UE ID (or (TARGET) V2X RX UE ID (or X bit ID)) and / or ( V2V) can be initialized according to the subframe (/ slot) index).

For example, when performing V2V communication, PSCCH and / or (interlocked) PSSCH related (A) (DM-RS) SEQUENCE GENERATION RULE and / or (B) (DM-RS) CS (/ OCC) INDEX SELECTION (/ DETERMINATION ) RULE and / or (C) GROUP / SEQUENCE HOPPING RULE can be defined as shown in Table 7 and Table 8. As an example, the following (some) proposed schemes (DM-RS) SEQUENCE (/ CS (/ OCC) INDEX) (and / or interference) when PSCCH and / or PSSCH transmission resources (some or all) overlap between different terminals We present methods that allow the randomization operation to be performed efficiently.

Hereinafter, through Table 7 and Table 8, when performing V2V communication, the PSCCH and / or (linked) PSSCH related (A) (DM-RS) SEQUENCE GENERATION RULE and / or (B) (DM-RS) CS (/ An example of OCC) INDEX SELECTION (/ DETERMINATION) RULE and / or (C) GROUP / SEQUENCE HOPPING RULE will be described. In this case, only the normal CP may be supported in the V2V WI, and the destination ID may not be transmitted through the SA. In addition, 16 CRC bits from the SA may be used to generate the PSSCH DMRS sequence and the data scrambling sequence.

TABLE 7

here,

Can be.

TABLE 8

here,

N _x may mean X bits in the SA used to generate the PSSCH DMRS sequence.

[Suggested Rule # 19] As an example, a bit (field) used for (linked) PSSCH DM-RS CS index (/ value) determination (eg, 16-bit CRC (C ₀ , C ₁ ,... C ₁₅ ), 2 bits that are preset (/ signaled) (or randomly selected) among (3) bit values of “C ₁₂ , C ₁₃ , C ₁₄ ” are selected from the selected PSCCH CS index (/ value) (eg , “2 bits”) can be used for SCRAMBLING. Here, as an example, when such a rule is applied, (A) the (final) 16-bit CRC of the PSCCH is “C ₀ , C ₁ ,... , Keep (/ apply) a C ₁₅ ”value (for example, only the CRC (and / or / or bit (field)) used to determine the (linked) PSSCH DM-RS CS index (/ value) And / or (B) (partly) the 16-bit CRC changed (partly) by the (appropriate) SCRAMBLING operation to be the (final) CRC of the PSCCH. In one example, the LSB (for example, the PSSCH DM-RS OCC index (/ value) may be changed if the corresponding rule is applied) among the 16-bit CRCs (C ₀ , C ₁ ,..., C ₁₅ ) of the PSCCH ( Or MSB) 2 bits (and / or 2 bits of a preset (/ signaled) (or randomly selected) specific position) to be SCRAMBLING to the selected PSCCH CS index (/ value) (eg, “2 bits”). can do. Here, in one example, if such a rule is applied, (A) the (some) modified 16-bit CRC with (partly) the SCRAMBLING operation will be the (final) CRC of the PSCCH and / or (B) the (final) of the PSCCH. The 16-bit CRC indicates “C ₀ , C ₁ ,... , Keep (/ apply) a C ₁₅ ”value (for example, only the CRC (and / or / or bit (field)) used to determine the (linked) PSSCH DM-RS CS index (/ value) It can be considered as changed by the SCRAMBLING operation. In one example, 16 bits (different) for SCRAMBLING use are pre-set (/ signaled) for each PSCCH CS index (/ value) (for example, “2 bits”), and the terminal causes (A) the selected PSCCH CS index. SCRAMBLING 16 bit (S ₀ , S ₁ ,…, S ₁₅ ) for SCRAMBLING linked with (/ value) and (generated) 16 bit CRC (C ₀ , C ₁ ,…, C ₁₅ ) of PSCCH , (Applicable) SCRAMBLING result value (W ₀ , W ₁ ,…, W ₁₅ ) to be the final 16-bit CRC of PSCCH and / or (B) the (final) 16-bit CRC of PSCCH is “C ₀ , C ₁ ,.. , C ₁₅ ”, but only 16-bit CRC (and / or bit (field)) used to determine (linked) PSSCH DM-RS CS index (/ value)“ W ₀ , W ₁ ,… , W ₁₅ "value (and / or (3) bit value of" W ₁₂ , W ₁₃ , W ₁₄ "among“ W ₀ , W ₁ ,…, W ₁₅ ”).

For example, (A) SCI FOMRAT configuration field (s) used in MODE 2 V2V SCHEDULING ( MODE2 _ SCH ) operation and / or (B) DCI FORMAT configuration field used in MODE 1 DYNAMIC V2V SCHEDULING ( MODE1_DYN ) operation. (S) may be defined as Here, as an example, FRA_INRETX field (in analogy LVRB form of a conventional LTE system) RESOURCE INDICATION VALUE (RIV) value (PSSCH transmission-related) (A) start subchannel index (/ location) information (SUB_START) and / or It may be defined in the form of informing the subchannel length (/ number) information ( SUB_LENGTH ) continuously allocated (/ positioned) (on a frequency domain). Here, as an example, when two PSSCH transmissions are set (/ signaled) for a specific (one) TB transmission, (A) SUB_START value is the start index (/ location) information of the subchannel in which the second PSSCH transmission is performed. ( SECDATA _ SUBST ) and / or (B) SUB_LENGTH may be interpreted as subchannel length (/ number) information ( SFDATA _ SUBLN ) used for first and second PSSCH transmissions. Here, as an example, the start index (/ location) information ( FIRDATA _ SUBST ) of the subchannel on which the first PSSCH transmission is performed is defined in advance by the receiving terminal (rather than being directly signaled through the FRA_INRETX field). (One-to-one) between “((blind) detected) (first) PSCCH resource index (/ location) information” and “start index (/ location) information of the subchannel on which the (linked) (first) PSSCH transmission is performed” ) Mapping (/ linkage) relationships allow you to implicitly identify them.

The following describes an example of the SCI FOMRAT configuration field (s) used in the MODE2_SCH operation and / or (B) the DCI FORMAT configuration field (s) used in the MODE1_DYN operation.

SCI has 1) PRIORITY: 3 bits, 2) Resource reservation: 4 bits, 3) MCS: 5 bits, 4) CRC: 16 bits 5) Retransmission index (RETX_INDEX): 1 bit, 6) Time gap between transmission initiation and retransmission (TGAP_INIRETX): 4 bits, 7) Frequency resource location (FRA_INRETX) of transmission start and retransmission: 8 bits, 8) Reserved bit (RSV_BIT): 7 bits may be set.

DCI is: 1) CIF: 3 bits, 2) lowest index of subchannel allocated to start of transmission (PSCCH_RA): 5 bits, 3) time gap between start of transmission and retransmission (as SA content): 4 bits, 4) start of transmission And frequency resource location (FRA_INRETX) of retransmission: 8 bits.

[Proposed Method # 20] As an example, when one PSSCH transmission is configured (signaled) for a specific (one) TB transmission, some information of the FRA_INRETX field (described above) (for example, “SECDATA_SUBST-related information”). ”) Becomes unnecessary. Is (that) In one example, the information required for this case (only) a sub-channel length (/ number) information (FDATA _ SUBLN) used for the first transmission PSSCH. Here, as an example, the (corresponding) unnecessary information related STATE (or value) and / or bits may be defined according to the below (some or all) rules.

(Example # 20-1) As an example, (A) assuming that up to 20 subchannels (on one subframe) can be set (/ signaled) to the (V2V) resource pool, to indicate FDATA_SUBLN information The number of bits required is the “5” bit (ie, “CEILING (LOG ₂ (20)) = 5” (where, for example, CEILING (X) is a function that derives the minimum information value greater than or equal to X)). And / or (B) assuming that K subchannels (on one subframe) have been set (/ signaled) to the (V2V) resource pool, the number of bits needed to indicate FDATA_SUBLN information is “CEILING (LOG _2). (K)) ”. Here, for example, for a specific (one) TB transmission, if two PSSCH transmissions are configured (/ signaled), the (necessary) FRA_INRETX field size is set to the “Q” bit (eg, “Q = 8”). assuming a, "(Q - 5)" ( and / or _{"(Q - CEILING (LOG 2} (K)))") is the remaining number of bits is not necessary analysis information related bits (/ treated).

(Example # 20-2) As an example, when two PSSCH transmissions are configured (/ signaled) for a particular (one) TB transmission, (actually) assuming that the (necessary) FRA_INRETX field size is "Q" bit, Multiple (part or all) SECDATA_SUBST values (preset (/ signaled)) that can be specified together with a specific (single) FDATA_SUBLN (or SFDATA_SUBLN) value (required) are interpreted as a STATE (or value) for unnecessary information. Can be considered).

(Example # 20-3) As an example, for a specific (one) TB transmission, when one PSSCH transmission is configured (/ signaled), the V2X RX UE (S) may transmit (via corresponding) V2X TX through the TGAP_INIRETX field. Since the UE can determine whether to perform one or two PSSCH transmissions (for a specific (one) TB), the RETX_INDEX related STATE (or value) can be interpreted (/ regarded) as unnecessary information. As another example, for a particular (single) TB transmission, when one PSSCH transmission is set up (/ signaled), a RETX_INDEX related value (or STATE) is a pre-set (/ signaled) (specific) value (or STATE). Here, as an example, a corresponding (specific) value (or STATE) (relating to RETX_INDEX) may be used for the purpose of “VIRTUAL CRC”.

(Example # 20-4) As an example, some bits that are preset (/ signaled) among RSV_BIT field related bits (eg, “7 bits”) are interpreted as unnecessary information related bits (or values). Can be.

For example, according to the following (partial) rule, by randomizing the unnecessary information related STATE (or value) and / or bits (described above), the PSSCH generated when (some or all) the PSSCH transmission resources of different terminals overlap (some or all). DM-RS) SEQUENCE (/ CS (/ OCC) INDEX) Mitigates COLLISION problems (e.g., through the operation) the PSCCH CRC is randomized, which (finally) results in PSSCH (DM-RS) SEQUENCE ( / CS (/ OCC) INDEX, etc.), where, for example, the above-described unnecessary information related STATE (or value) and / or bit generation (for example, specific (one) TB transmission is performed. For this purpose, one PSSCH transmission is established (/ signaled) is only one example, and the (some or all) proposed method of the present invention (STATE (or value) related to unnecessary information and / or bits generated) In various cases (for example, MODE1_DYN DCI FORMAT and / or MODE2_SCH SCI FORM For AT), the (additional) margin caused by the FRA_INRETX size being changed (depending on the total number of subchannels (K) that make up the V2V resource pool (in one subframe) (pre-set / signaled). Bit (for example, “(8-CEILING (LOG ₂ (K (K + 1) / 2)) (FRA_INRETX size)) ”and / or“ “(8-CEILING (LOG ₂₎ (K (K + 1) / 2)) (FRA_INRETX size)-CEILING (LOG2 (K)) (PSCCH_RA size))))) and / or pre-defined (/ signaled) (target) payload size ( For example, the (target) payload size for MODE1_DYN DCI FORMAT and MODE2_SCH SCI FORMAT are each (previous) DCI FORMAT 0 payload size (see above), 48 bits (see above). In this case, the (additional) bits generated by changing the size of FRA_INRETX may be considered as unnecessary information related bits). Here, as an example, the 16-bit CRC (C ₀ , C ₁ ,…, C ₁₅ ) of the PSCCH is randomized (/ ₁₅ ) through a corresponding randomization operation of the unnecessary information related STATE (or value) and / or bits. Change) and finally the PSSCH DM-RS CS (/ SEQUENCE / OCC) (index) is also randomized (/ change) (see Table 7 and / or Table 8). Here, as an example, (A) (described above) (example # 20-3) and / or (B) (example # 20-4) and / or (C) the FRA_INRETX size is (preset (/ signaled)). Applying the below (some) rules to the (additional) marginal bits resulting from the change (in accordance with the number (K) of total subchannels constituting the V2V resource pool (in one subframe) constitutes the V2V resource pool) If the total number of subchannels to be specified is less than or equal to a preset (/ signaling) value (for example, “1”) (for example, the FRA_INRETX field size becomes smaller (for example, “0”). PSSCH DMRS (/ PSCCH CRC) randomization may be limited to (which may be interpreted as a situation in which it is difficult to derive additionally).

(Rule # 20-1) As an example, a transmitting terminal may be configured to generate a random information related STATE (or value) and / or a randomly selected value (and / or ((serving)) from a base station (or network) (described above). ) Can be set as a preset (/ signaled value). Here, as an example, the unnecessary information related STATE (or value) and / or bit by bit (for example, (example # 20-1), (example # 20-2), (example # 20-3)) , (Example # 20-4) may be defined (/ signaled) differently under the condition that these rules apply to. Here, as an example, if the number of subchannels (/ signaled) set to resource pool (for V2X communication) is “1” (or / or for one (1) TB transmission, one PSSCH transmission is configured). (In / signaled), the size of FRA_INRETX (actually used) will be “0”, so STATE (or value) for unnecessary information of (Example # 20-3) (for example, STATE (or value) for RETX_INDEX) ) And / or allow the rule to be applied to bits, and in other cases (eg, for V2X communication), the number of subchannels (/ signaled) into the resource pool is not "1" (and / or If greater than “1” (and / or for one (1) TB transmission, one PSSCH transmission is set up (/ signaled)), then (Example # 20-2) (for example (actually Multiple (part or all) (preset (/ signaled)) that can be specified with a specific (one) FDATA_SUBLN value required The rule may be applied to the STATE (or value) and / or bits related to unnecessary information of the SECDATA_SUBST value (or STATE). Here, for example, in an environment in which one PSSCH transmission is performed (for a specific (one) TB transmission) (for V2X communication) regardless of the number of subchannels set (/ signaled) to a resource pool (example) # 20-3) Ensure that the above rules apply to unnecessary information related STATE (or value) and / or bits (e.g. RETX_INDEX related STATE (or value)) and set to resource pool (for V2X communication) (Eg # 20-2) (e.g., actually required) with a specific (one) FDATA_SUBLN value only if the number of sub-channels / signals is not "1" (and / or greater than "1"). This rule can be applied to STATE (or value) and / or bits of unnecessary information related to a plurality of (some or all) SECDATA_SUBST values (or STATEs) that can be specified together (preset / signaled). There is also.

(Rule # 20-2) In one example, a transmitting terminal may be configured to transmit (A) the unnecessary information related STATE (or value) and / or bits (A) to transmit (or (target) receive) a terminal identifier and / or (B). Specified by a derived (/ calculated) value based on a predefined (randomized / hopped) function with the selected PSCCH CS index (/ value) (e.g., "2 bits") as an input parameter ( Or (C) transmit (or (target) receive) a terminal identifier and / or (D) select a value derived by a selected PSCCH CS index (/ value) (eg, “2 bits”) or the like. . Here, as an example, if the unnecessary information related bits (described above) are defined in the form (example # 20-1), if "(Q-5)" (and / or "(Q-CEILING (LOG ₂ (K)) )) ") (for example," is greater than Q = 8 "," K = 20 "), the bit value (PC_ SELCSBIT) (e. g., indicating a PSCCH CS index (/ values) these" two-bit ") (A) PC_SELCSBIT bit (/ value) (or bit (/ value) derived from the PC_SELCSBIT bit) in the bit "(Q-5)" (and / or "(Q-CEILING (LOG ₂ (K)))"). The (bit) position that should be specified in) is set (/ signaled) in advance and / or (B) “(Q-5-PC_SELCSBIT)” (and / or “(Q-CEILING (LOG ₂ (K)))- PC_SELCSBIT) ”), so that the remaining bits (eg,“ 1 ”bits) can be set to ZERO PADDING (or to a preset value (/ signaled)).

For example, for a particular (single) TB transmission, when one PSSCH transmission is configured (/ signaled), it may be (exceptionally) to reduce (exceptionally) the FRA_INRETX field size (described above). (Q-5) ”,“ (Q-CEILING (LOG ₂ (K))) ”).

For example, a PSCCH CRC used to determine a parameter such as a PSSCH-related (DM-RS) SEQUENCE (/ CS (/ OCC) INDEX, etc. transmitted at a specific time point may be transmitted in the form of (FDM) in which (PSCCH and (linked) Case) may be defined as a PSCCH CRC transmitted at the same time point as the PSSCH (and / or a PSCCH CRC transmitted together for (requiredly) for PSSCH transmission).

It is obvious that examples of the proposed scheme described above may also be regarded as a kind of proposed schemes as they may be included as one of the implementation methods of the present invention. In addition, although the above-described proposal schemes may be independently implemented, some proposal schemes may be implemented in combination (or merge). For example, the present invention has been described a proposal method based on the 3GPP LTE system for convenience of description, the scope of the system to which the proposed method is applied can be extended to other systems in addition to the 3GPP LTE system. As an example, the proposed schemes of the present invention can be extended and applied for D2D communication. Here, as an example, D2D communication means that the UE communicates directly with another UE using a wireless channel, where, for example, the UE means a terminal of a user, but network equipment such as a base station is used for communication between UEs. Therefore, when transmitting / receiving a signal, it can also be regarded as a kind of UE. Also, as an example, the proposed schemes of the present invention may be limitedly applied only to the MODE 2 V2X operation (and / or the MODE 1 V2X operation). In addition, as an example, the proposed schemes of the present invention ('(trans) resource (re) selection operation' is triggered (as the predefined (/ signaled) condition is satisfied)) '(LOW LAYER) buffer' ( And / or if a packet (/ message) (to be transmitted or generated) is present on (or 'PDCP LAYER') (or a packet (/ message) is generated) (or '(LOW LAYER) buffer' (and / Alternatively, the present invention may be limited to the case where the packet (to be transmitted or generated) (/ message) does not exist (or the packet (/ message) is not generated) on the 'PDCP LAYER'). Also, as an example, the proposed schemes of the present invention may be limitedly applied only when the PSCCH and the (used) PSSCH are not located (or located) in the adjacent RB (S) on the same subframe. In addition, as an example, the proposed schemes of the present invention not only V2V MODE 1 (/ MODE 2) DYNAMIC SCHEDULING operation but also V2V MODE 1 (/ MODE 2) SEMI-PERSISTENT SCHEDULING ( SPS ) operation (and / or V2X MODE 1 (/ MODE). 2) DYNAMIC SCHEDULING operation and / or V2X MODE 1 (/ MODE 2) SPS operation) can be extended. Also, as an example, in the present invention, "transmission resource selection" wording may be interpreted as (extended) "transmission resource (re) reservation".

39 is a block diagram illustrating a terminal in which an embodiment of the present invention is implemented.

Referring to FIG. 39, the terminal 1100 includes a processor 1110, a memory 1120, and an RF unit 1130.

According to an embodiment of the present disclosure, the processor 1110 may execute a function / operation / method described by the present invention. For example, the processor 1110 may perform a sensing during a terminal-specific sensing period, select a resource for V2X communication, and perform V2X communication based on the selected resource.

For example, the processor 1110 may select a resource for performing V2X communication within a range satisfying a latency request and perform V2X communication based on the selected resource.

For example, the processor 1110 selects a resource for performing the V2X message transmission by sensing in a subchannel unit having a size corresponding to the size of the subchannel used for V2X message transmission, and based on the selected resource. The V2X message transmission may be performed.

For example, the processor 1110 may make a reservation for a finite number of resources on which V2X communication is performed and perform the V2X communication on the reserved finite number of resources.

For example, the processor 1110 determines whether a resource reselection condition is satisfied, and if the resource reselection condition is satisfied, performs a reselection for a resource on which vehicle-to-X communication is performed. And perform the V2X communication based on the selected resource.

For example, the processor 1110 may select a subframe other than the subframe related to the subframe in which the transmission is performed during the sensing period in the selection period and perform V2X communication based on the selected subframe.

For example, the processor 1110 may allocate a V2X resource pool to the remaining subframes except for a specific subframe and perform V2X communication on the allocated V2X resource pool.

The RF unit 1130 is connected to the processor 1110 to transmit and receive a radio signal.

The processor may include application-specific integrated circuits (ASICs), other chipsets, logic circuits, and / or data processing devices. The memory may include read-only memory (ROM), random access memory (RAM), flash memory, memory card, storage medium and / or other storage device. The RF unit may include a baseband circuit for processing a radio signal. When the embodiment is implemented in software, the above-described technique may be implemented as a module (process, function, etc.) for performing the above-described function. The module may be stored in memory and executed by a processor. The memory may be internal or external to the processor and may be coupled to the processor by various well known means.

Claims (11)

1. In the V2X operation method performed by a vehicle-to-X (V2X) terminal in a wireless communication system,

   Selecting a subframe in the selection period except for the subframe related to the subframe in which the transmission was performed during the sensing period; And

   Performing V2X communication based on the selected subframe.
2. The method of claim 1,

   The subframe excluded is a subframe in the selection period.
3. The method of claim 1,

   If the subframe in which the transmission is performed during the sensing period and a subframe corresponding to a specific period overlap with the subframe reserved according to the resource reservation period of the related subframe, the related subframe is excluded. .
4. The method of claim 3,

   The subframe in which transmission is performed during the sensing period is subframe k, where k is a positive integer,

   The subframe k and the subframe corresponding to the specific period are subframes (k + 100 * i), where i is a positive integer set by the base station,

   When the subframe (k + 100 * i) and the subframe (y + P * j) overlap, the subframe y is excluded from the selection, where y is a positive integer and P is a resource reservation period, j Is a positive integer.
5. The method of claim 4, wherein

   The range of j is determined by a positive integer value proportional to the counter value arbitrarily determined by the V2X terminal.
6. The method of claim 5,

   And the counter value is a value between 5 and 15, inclusive.
7. The method of claim 4, wherein

   Wherein P is 100 ms.
8. The method of claim 1,

   The sensing interval is 1s and the selection interval is 100ms.
9. The method of claim 1,

   The sensing section is a sensing window, characterized in that the selection section is a selection window.
10. The method of claim 9,

    The sensing window is characterized in that the terminal specific.
11. UE (User equipment; UE),

    RF (Radio Frequency) unit for transmitting and receiving a radio signal; And

    A processor operating in conjunction with the RF unit; Including, but the processor,

    Selecting a subframe in the selection interval except for the subframe related to the subframe in which the transmission was performed during the sensing interval, and

    And perform V2X communication based on the selected subframe.

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