Terminal, communication system, and communication method

Abstract

A terminal is provided with: a control unit that selects, as a sidelink reference signal which can be used for measuring sidelink path loss, a defined or preset sidelink reference signal, and selects a defined or preset port or index for receiving the selected reference signal; and a reception unit that receives the reference signal selected by the control unit.

Description

[Technical field]

[0001] The present invention relates to a terminal and a communication method in a wireless communication system. [Background technology]

[0002] In LTE (Long Term Evolution) and successor systems to LTE (e.g., LTE-A (LTE Advanced) and NR (New Radio) (also known as 5G)), sidelink technology (also known as D2D (Device to Device)) is being considered, which enables terminals such as User Equipment (UE) to communicate directly with each other without going through a base station.

[0003] In addition, the realization of V2X (Vehicle to Everything) is being considered, and specifications are being developed. Here, V2X is a part of ITS (Intelligent Transport Systems), and as shown in Figure 1, it is a general term for V2V (Vehicle to Vehicle), which means a form of communication between automobiles, V2I (Vehicle to Infrastructure), which means a form of communication between automobiles and roadside units (RSU: Road-Side Units) installed on the side of the road, V2N (Vehicle to Nomadic device), which means a form of communication between automobiles and the driver's mobile device, and V2P (Vehicle to Pedestrian), which means a form of communication between automobiles and the mobile devices of pedestrians. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP TS 36.213 V15.2.0(2018-06) [Non-Patent Document 2] 3GPP TS 38.211 V15.6.0(2019-06) [Non-Patent Document 3] 3GPP TS 38.214 V15.5.0(2019-03) [Non-Patent Document 4] 3GPP TS 38.331 V15.5.1(2019-04) Summary of the Invention [Problem to be solved by the invention]

[0005] In the case of NR-Uu in Release 15, it is possible to use the SS / PBCH block (SSB) and CSI-RS as reference signals for measuring path loss.

[0006] In NR sidelink communications, when measuring sidelink pathloss, a method for specifying a reference signal for measuring the pathloss is required. [Means for solving the problem]

[0007] According to one aspect of the present invention, a mobile station includes a receiving unit that receives a sidelink demodulation reference signal from another terminal at a DMRS port, the sidelink demodulation reference signal being used for measuring a sidelink path loss, and a control unit that designates a DMRS port that receives the demodulation reference signal by using control information received from the other terminal; The receiver receives the sidelink demodulation reference signal via a sidelink data channel, and calculates a transmission power of the sidelink data channel for each transmission opportunity of the sidelink data channel. A terminal is provided. Effect of the Invention

[0008] According to an embodiment, a method for specifying a reference signal for performing sidelink path loss measurements is provided. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram for explaining V2X. [Figure 2A] FIG. 13 is a diagram for explaining a side link. [Figure 2B] FIG. 13 is a diagram for explaining a side link. [Diagram 3]FIG. 1 is a diagram for explaining a MAC PDU used in sidelink communication. [Figure 4] FIG. 13 is a diagram for explaining the format of an SL-SCH subheader. [Diagram 5] FIG. 1 is a diagram for explaining an example of a channel structure used in a side link in LTE-V2X. [Figure 6] 1 is a diagram illustrating an example of a configuration of a wireless communication system according to an embodiment; [Figure 7] FIG. 11 is a diagram for explaining a resource selection operation of a terminal. [Figure 8A] FIG. 1 is a diagram showing an overview of SL transmission mode 1 defined in NR V2X. [Figure 8B] FIG. 13 is a diagram showing an overview of SL transmission mode 2a. [Figure 8C] FIG. 13 is a diagram showing an overview of SL transmission mode 2c. [Figure 8D] FIG. 13 is a diagram showing an overview of SL transmission mode 2d. [Figure 9A] FIG. 1 illustrates an example of unicast PSCCH / PSSCH transmission. [Figure 9B] FIG. 13 is a diagram illustrating an example of groupcast PSCCH / PSSCH transmission. [Figure 9C] FIG. 1 illustrates an example of broadcast PSCCH / PSSCH transmission. [Figure 10] FIG. 1 is a diagram illustrating an example of a formula used for transmission power control in a side link of LTE. [Figure 11A] A figure showing an example of a provision for boosting the transmission power of a reference signal in NR-Uu. [Figure 11B] A figure showing an example of a provision for boosting the transmission power of a reference signal in NR-Uu. [Figure 11C] A figure showing an example of a provision for boosting the transmission power of a reference signal in NR-Uu. [Figure 12]FIG. 13 illustrates an example of a slot structure including PSCCH symbols with CSI-RS. [Figure 13] A figure showing an example of a case where open-loop transmission power control based on sidelink path loss is performed for NR sidelink groupcast communication. [Figure 14] A figure showing an example of applying open-loop transmission power control based on sidelink path loss when distance-based HARQ is applied. [Figure 15] FIG. 13 is a diagram illustrating an example of specifying that path loss is measured using a reference signal based on PUSCH-PathlossReferenceRS. [Figure 16] FIG. 13 is a diagram illustrating an example of a PUSCH-PathlossReferenceRS information element. [Figure 17] FIG. 11 is a diagram illustrating an example of the correspondence between a TCI state and a reference signal. [Figure 18] A diagram showing two example methods for a transmitting terminal to obtain L3-RSRP measurement results. [Figure 19] FIG. 2 is a diagram illustrating an example of a functional configuration of a base station according to an embodiment. [Figure 20] FIG. 2 is a diagram illustrating an example of a functional configuration of a terminal according to an embodiment. [Figure 21] FIG. 2 is a diagram illustrating an example of a hardware configuration of a base station and a terminal according to an embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention (the present embodiment) will be described with reference to the drawings. Note that the embodiment described below is merely an example, and the embodiment to which the present invention is applied is not limited to the following embodiment.

[0011] In the present embodiment, the direct communication method between terminals is assumed to be LTE or NR sidelink (SL (Sidelink)), but the direct communication method is not limited to this method. In addition, the name "sidelink" is an example, and the name "sidelink" may not be used, and UL (Uplink) may include the function of SL. SL may be distinguished from DL (Downlink) or UL by differences in frequency or time resources, and may be named otherwise.

[0012] In addition, UL and SL may be distinguished by differences in one or a combination of more than one of time resources, frequency resources, time-frequency resources, reference signals used to determine pathloss in transmission power control, and reference signals used for synchronization (PSS / SSS / PSSS / SSSS).

[0013] For example, in UL, a reference signal of antenna port X_ANT is used as a reference signal to be referenced for determining pathloss in transmission power control, and in SL (including UL used as SL), a reference signal of antenna port Y_ANT is used as a reference signal to be referenced for determining pathloss in transmission power control.

[0014] In addition, in this embodiment, a terminal (which may be called user equipment (UE)) is mainly assumed to be mounted on a vehicle, but the embodiment of the present invention is not limited to this form. For example, the terminal may be a terminal held by a person, a device mounted on a drone or an aircraft, a base station, an RSU, a relay station (relay node), a user equipment having scheduling capability, etc.

[0015] (Sidelink Overview) In this embodiment, since the sidelink is a basic technology, an overview of the sidelink will be described first as a basic example. The example of the technology described here is a technology specified in 3GPP Rel.14, etc. The technology may be used in NR, or a technology different from the technology may be used in NR. Here, the sidelink communication may be defined as direct communication between two or more adjacent user equipments without going through a network node while using E-UTRA technology. The sidelink may be defined as an interface between user equipments in the sidelink communication.

[0016] Sidelink is roughly divided into "discovery" and "communication." As for "discovery," as shown in FIG. 2A, a resource pool for discovery messages is configured for each discovery period, and a terminal (referred to as UE) transmits a discovery message (discovery signal) within the resource pool. More specifically, there are Type 1 and Type 2b. In Type 1, a terminal may autonomously select a transmission resource from a resource pool. In Type 2b, semi-static resources may be assigned by higher layer signaling (e.g., RRC signal) (PC5-RRC, which is sidelink RRC signaling, may be applied instead of higher layer signaling, and DCI and / or SCI may be applied).

[0017] Regarding "communication," as shown in FIG. 2B, a resource pool for SCI (Sidelink Control Information) / data transmission is periodically set for each SC (Sidelink Control) period. The transmitting terminal notifies the receiving side of the data transmission resource (PSSCH resource pool) and the like by SCI using resources selected from the control resource pool (PSCCH resource pool), and transmits data using the data transmission resource. More specifically, there are two modes for "communication." In mode 1, resources may be dynamically allocated by the (E)PDCCH ((Enhanced) Physical Downlink Control Channel) sent from the base station to the terminal. In mode 2, the terminal may autonomously select a transmission resource from the resource pool. The resource pool may be notified by SIB (MIB, higher layer signaling, PC5-RRC which is sidelink RRC signaling, etc. may be applied instead of SIB), or a predefined one may be used.

[0018] In addition to Mode 1 and Mode 2, Rel-14 also has Mode 3 and Mode 4. In Rel-14, it is possible to transmit SCI and data simultaneously (in one subframe) using resource blocks adjacent in the frequency direction. Note that SCI is sometimes referred to as SA (scheduling assignment).

[0019] The channel used for "discovery" may be referred to as PSDCH (Physical Sidelink Discovery Channel), the channel for transmitting control information such as SCI in "communication" may be referred to as PSCCH (Physical Sidelink Control Channel), and the channel for transmitting data may be referred to as PSSCH (Physical Sidelink Shared Channel). PSCCH and PSSCH may have a PUSCH-based structure and may be structured to insert a DMRS (Demodulation Reference Signal). In this specification, PSCCH may be referred to as a sidelink control channel, and PSSCH may be referred to as a sidelink shared channel. A signal transmitted via PSCCH may be referred to as a sidelink control signal, and a signal transmitted via PSSCH may be referred to as a sidelink data signal.

[0020] A Medium Access Control (MAC) Protocol Data Unit (PDU) used in a sidelink may be composed of at least a MAC header, a MAC Control element, a MAC Service Data Unit (SDU), and Padding, as shown in Fig. 3. The MAC PDU may include other information. The MAC header may be composed of one Sidelink Shared Channel (SL-SCH) subheader and one or more MAC PDU subheaders.

[0021] As shown in FIG. 4, the SL-SCH subheader may be composed of a MAC PDU format version (V), source information (SRC), destination information (DST), a reserved bit (R), and the like. V is assigned to the beginning of the SL-SCH subheader and may indicate the MAC PDU format version used by the terminal. Information about the source may be set in the source information. An identifier about the ProSe UE ID may be set in the source information. Information about the destination may be set in the destination information. Information about the ProSe Layer-2 Group ID of the destination may be set in the destination information.

[0022] An example of a sidelink channel structure in LTE-V2X is shown in Figure 5. As shown in Figure 5, a PSCCH resource pool and a PSSCH resource pool used for "communication" may be allocated. Also, a PSDCH resource pool used for "discovery" is allocated with a longer period than the period of the "communication" channel. Note that NR-V2X does not need to include PSDCH.

[0023] Also, a PSSS (Primary Sidelink Synchronization signal) and an SSSS (Secondary Sidelink Synchronization signal) may be used as a synchronization signal for the sidelink. Also, a PSBCH (Physical Sidelink Broadcast Channel) may be used to transmit broadcast information such as a system band, a frame number, and resource configuration information of the sidelink for out-of-coverage operation. The PSSS / SSSS and PSBCH are transmitted in, for example, one subframe. The PSSS / SSSS may be referred to as SLSS.

[0024] Note that V2X assumed in this embodiment is a method related to "communication." However, in this embodiment, there may be no distinction between "communication" and "discovery." Also, the technology according to this embodiment may be applied to "discovery."

[0025] (System Configuration) Fig. 6 is a diagram showing a configuration example of a wireless communication system according to the present embodiment. As shown in Fig. 6, the wireless communication system according to the present embodiment includes a base station 10, a terminal 20A, and a terminal 20B. Note that, although there may be many terminals in practice, Fig. 6 shows terminal 20A and terminal 20B as examples.

[0026] In Fig. 6, the terminal 20A is intended to be the transmitting side, and the terminal 20B is intended to be the receiving side, but both the terminal 20A and the terminal 20B have both a transmitting function and a receiving function. Hereinafter, when there is no particular distinction between the terminals 20A, 20B, etc., they will be simply described as "terminal 20" or "terminal". Fig. 6 shows, as an example, a case where the terminals 20A and 20B are both within the coverage, but the operation in this embodiment can be applied to any of the cases where all the terminals 20 are within the coverage, where some of the terminals 20 are within the coverage and the other terminals 20 are outside the coverage, and where all the terminals 20 are outside the coverage.

[0027] In this embodiment, the terminal 20 is, for example, a device mounted on a vehicle such as an automobile, and has a cellular communication function as a user equipment (UE) in LTE or NR, and a side link function. Furthermore, the terminal 20 includes a function for acquiring report information (position, event information, etc.) such as a GPS device, a camera, various sensors, etc. The terminal 20 may also be a general mobile terminal (such as a smartphone). The terminal 20 may also be an RSU. The RSU may be a UE type RSU having a UE function, a BS type RSU (which may be called a gNB type UE) having a base station function, or a relay station.

[0028] It should be noted that the terminal 20 does not need to be a device in a single housing, and even if various sensors are distributed throughout a vehicle, for example, a device including the various sensors is the terminal 20. The terminal 20 may not include the various sensors, but may have a function for transmitting and receiving data to and from the various sensors.

[0029] Furthermore, the sidelink transmission process of terminal 20 is basically the same as the UL transmission process in LTE or NR. For example, terminal 20 scrambles and modulates codewords of transmission data to generate complex-valued symbols, maps the complex-valued symbols (transmission signals) to one or two layers, and performs precoding. Then, terminal 20 maps the precoded complex-valued symbols to resource elements to generate transmission signals (e.g., CP-OFDM, DFT-s-OFDM), and transmits them from each antenna port.

[0030] The base station 10 has a function of cellular communication as the base station 10 in LTE or NR, and a function for enabling communication of the terminal 20 in the present embodiment (e.g., resource pool setting, resource allocation, etc.). The base station 10 may be an RSU (gNB type RSU), a relay station, or a terminal having a scheduling function.

[0031] In the wireless communication system according to the present embodiment, the signal waveform used by the terminal 20 for SL or UL may be OFDMA, SC-FDMA, or other signal waveform. In the wireless communication system according to the present embodiment, as an example, a frame consisting of a plurality of subframes (e.g., 10 subframes) is formed in the time direction, and a plurality of subcarriers are formed in the frequency direction. One subframe is an example of one transmission time interval (TTI). However, the TTI is not necessarily a subframe. For example, the TTI may be a slot, a mini-slot, or other time domain unit. The number of slots per subframe may be determined according to the subcarrier interval. The number of symbols per slot may be 14 symbols. Furthermore, one symbol may include a cyclic prefix (CP) that is a guard period for reducing inter-symbol interference caused by multipath.

[0032] In this embodiment, the terminal 20 can take any of the following modes: mode 1 in which resources are dynamically allocated by an (E)PDCCH ((Enhanced) Physical Downlink Control Channel) sent from the base station 10 to the terminal, mode 2 in which the terminal autonomously selects transmission resources from a resource pool, a mode in which resources for SL signal transmission are allocated by the base station 10 (hereinafter referred to as mode 3), and a mode in which resources for SL signal transmission are autonomously selected (hereinafter referred to as mode 4). The mode is set, for example, by higher layer signaling from the base station 10 to the terminal 20 (for example, notification of a parameter such as scheduled or ue-Selected).

[0033] As shown in Fig. 7, a mode 4 terminal (shown as UE in Fig. 7) selects radio resources from a synchronized common time-frequency grid (or time and frequency domain). For example, terminal 20 performs sensing in the background, identifies resources with good sensing results and that are not reserved by other terminals as candidate resources, and selects a resource to be used for transmission from the candidate resources.

[0034] (Overview of NR V2X) In NR V2X, transmission modes similar to SL transmission mode 3 and SL transmission mode 4, which are specified in LTE V2X, are specified. Note that the transmission mode may be read as resource allocation mode, and the name is not limited to this.

[0035] Hereinafter, an overview of the transmission modes defined in V2X of NR will be described with reference to FIGS. 8A to 8D.

[0036] 8A is a diagram showing an overview of SL transmission mode 1 defined in NR V2X. SL transmission mode 1 defined in NR V2X corresponds to SL transmission mode 3 defined in LTE V2X. In SL transmission mode 1 defined in NR V2X, base station 10 schedules transmission resources and assigns the transmission resources to transmitting terminal 20A. Terminal 20A transmits a signal to receiving terminal 20B using the assigned transmission resources.

[0037] 8B, 8C, and 8D are diagrams showing an overview of SL transmission mode 2 defined in NR V2X. SL transmission mode 2 defined in NR V2X corresponds to SL transmission mode 4 defined in LTE V2X.

[0038] 8B is a diagram showing an overview of the SL transmission mode 2a. In the SL transmission mode 2a, for example, the transmitting terminal 20A autonomously selects a transmission resource and transmits a signal to the receiving terminal 20B using the selected transmission resource.

[0039] 8C is a diagram showing an overview of the SL transmission mode 2c. In the SL transmission mode 2c, for example, the base station 10 sets transmission resources of a fixed cycle / pattern in the terminal 20A in advance (for example, by a parameter of an upper layer), and the terminal 20A transmits a signal to the receiving terminal 20B by the transmission resources of the fixed cycle / pattern set in advance. Here, instead of the base station 10 setting transmission resources of a fixed cycle / pattern in the terminal 20A in advance, for example, the transmission resources of a fixed cycle / pattern may be set in the terminal 20A in advance according to the specifications.

[0040] 8D is a diagram showing an overview of SL transmission mode 2d. In SL transmission mode 2d, for example, terminal 20 performs the same operation as base station 10. Specifically, terminal 20 schedules transmission resources and allocates the transmission resources to transmitting terminal 20A. Terminal 20A may transmit to receiving terminal 20B using the allocated communication resources. In other words, terminal 20 may control transmissions of other terminals 20 (for example, terminal 20A and / or terminal 20B).

[0041] Furthermore, in NR, as shown in FIGS. 9A to 9C, three types of communication are currently being considered: unicast, groupcast, and broadcast.

[0042] 9A is a diagram showing an example of unicast Physical Sidelink Shared Channel (PSCCH) / Physical Sidelink Control Channel (PSSCH) transmission. Unicast refers to, for example, one-to-one transmission from a transmitting terminal 20A to a receiving terminal 20B.

[0043] 9B is a diagram showing an example of groupcast PSCCH / PSSCH transmission. Groupcast refers to, for example, transmission from terminal 20A on the transmitting side to terminals 20B and 20B′ which are a group of terminals 20 on the receiving side.

[0044] 9C is a diagram showing an example of broadcast PSCCH / PSSCH transmission. Broadcast refers to transmission to terminal 20B, terminal 20B', and terminal 20B'', which are all receiving terminals 20 within a predetermined range from transmitting terminal 20A, for example.

[0045] It is expected that the sidelink (SL) of New Radio (NR) will support transmission power control.

[0046] In 3GPP Release 16, it is assumed that open-loop transmitter power control (OLPC) will be supported. In the open-loop transmission power control, the terminal 20 measures the received power of a signal from a base station and determines the uplink transmission power. In the open-loop transmission power control of LTE sidelink communication, downlink (DL) propagation loss (path loss) is used. In NR sidelink communication, unicast and groupcast are introduced, and it is relatively easy to measure the sidelink path loss. Therefore, in the open-loop transmission power control of NR sidelink communication, it is assumed that the downlink path loss and / or the sidelink path loss will be used.

[0047] In NR sidelink unicast communication, the receiving terminal 20 transmits sidelink RSRP (SL-Reference Signal Received Power) to the transmitting terminal 20. In the case of open-loop transmission power control in NR sidelink unicast communication, the transmitting terminal 20 estimates (may measure, calculate, derive, etc.) the path loss. Before the receiving terminal 20 becomes able to use SL-RSRP, it is expected that future consideration will be given to how to perform pathloss estimation for open-loop transmission power control.

[0048] In closed-loop transmitter power control, the base station 10 measures the uplink reception power and specifies the transmission power of the terminal 20. However, in the sidelink of Release 16, it is not assumed that the closed-loop transmission power control is adopted, that is, that the transmission power control of the sidelink does not support the TPC (Transmission Power Control) command. However, in the sidelink of future NR, there is a possibility that the closed-loop transmission power control is adopted, and the present disclosure may be applied to the case where the closed-loop transmission power control is used.

[0049] For the open-loop transmission power control of the NR sidelink, it is assumed that it is possible to configure the terminal 20 to use only the path loss of the downlink (DL: between the terminal 20 on the transmitting side and the base station 10 (gNB)), to configure the terminal 20 to use only the path loss of the sidelink (SL: between the terminal 20 on the transmitting side and the terminal 20 on the receiving side), and to configure the terminal 20 to use the path loss of the downlink and the path loss of the sidelink. In the open-loop transmission power control of the NR sidelink, when the terminal 20 is configured to use the path loss of the downlink and the path loss of the sidelink, it is assumed that the minimum power value is adopted among the power value derived by the open-loop transmission power control based on the downlink pathloss and the power value derived by the open-loop transmission power control based on the path loss of the sidelink. In addition, it is assumed that the value of P0 and the value of α used for the open-loop transmission power are set separately for the path loss of the downlink and the path loss of the sidelink.

[0050] Fig. 10 is a diagram showing an example of a formula used for transmission power control in the sidelink of LTE. According to the formula shown in Fig. 10, transmission power is distributed between the Physical Sidelink Shared Channel (PSSCH) and the Physical Sidelink Control Channel (PSCCH). According to the formula shown in Fig. 10, the transmission power allocated to the PSCCH is greater than the transmission power allocated to the PSSCH.

[0051] (Assignment A) In NR sidelink communication, it is not specified at present how to control the transmission power of the sidelink Channel State Information Reference Signal (CSI-RS). In addition, in NR sidelink communication, it is not specified at present how to control the transmission power of the sidelink Phase Tracking Reference Signal (PTRS). For example, it is not specified at present whether to apply power-boosting to the sidelink CSI-RS and whether to apply power-boosting to the sidelink PTRS. In addition, hereinafter, CSI-RS may mean the sidelink CSI-RS (SL-CSI-RS). Similarly, PT-RS may mean the sidelink PT-RS (SL-PT-RS). In addition, the names of each are not limited to this, and SL-CSI-RS may be an RS used for sidelink CSI measurement, etc. Similarly, SL-PT-RS may be an RS used for sidelink phase compensation.

[0052] Figures 11A, 11B, and 11C are diagrams showing examples of provisions for boosting the transmission power of a reference signal in NR-Uu (an interface between a 5G terminal 20 and a 5G Radio Access Network (RAN)) relative to the transmission power allocated to a PDSCH or a PUSCH.

[0053] FIG. 11A is a diagram showing an example of boosting definition for PTRS in the uplink of NR-Uu. According to the example shown in FIG. 11, a phase-tracking reference signal (PT-RS) is transmitted only in resource blocks used for PUSCH. The PT-RS is expressed as

number

[0054] FIG. 11B is a diagram showing an example of a boost provision for a PTRS in the downlink of NR-Uu. Table 4.1.2 shown in the example of FIG. 11B shows the ratio of PT-RS Energy per Resource Element (EPRE) to the EPRE of the Physical Downlink Shared Channel (PDSCH) for each resource element and for each layer (ρ PTRS ) based on the amplitude scaling factor β PTRS In Table 4.1.2, when the parameter epre-Ratio of the higher layer is set to zero and the number of layers of the PDSCH is greater than 1, β PTRS The value of becomes greater than 1, and the transmission power of the PTRS is boosted (increased) relative to the transmission power allocated to the PDSCH.

[0055] Fig. 11C is a diagram showing an example of the provision of boost for CSI-RS of NR-Uu. In the example of Fig. 11C, it is specified that the EPRE of the downlink CSI-RS is derived from the downlink transmission power of the Synchronization Signal and Physical Broadcast Channel (SS / PBCH) block given by the parameter ss-PBCH-BlockPower and the power offset of the CSI-RS given by the parameter powerControlOffsetSS. In other words, the transmission power of the CSI-RS may be boosted relative to the transmission power of the SS / PBCH block.

[0056] (Proposal A) (Option A1) Terminal 20 may be able to set the transmission power value of the CSI-RS associated with the PSSCH to a value different from the transmission power value allocated to the PSSCH. Terminal 20 may also be able to set the transmission power value of the PT-RS associated with the PSSCH to a value different from the transmission power value allocated to the PSSCH.

[0057] (A1-1) The function for determining (which may be calculated, derived, etc.) the transmission power of the CSI-RS may be a function with the value of the transmission power allocated to the PSSCH as a variable. Similarly, the function for calculating the transmission power of the PT-RS may be a function with the value of the transmission power allocated to the PSSCH as a variable. For example, the transmission power of the CSI-RS may be capable of being calculated using a ratio to the value of the transmission power allocated to the PSSCH. Similarly, the transmission power of the PT-RS may be capable of being calculated using a ratio to the value of the transmission power allocated to the PSSCH.

[0058] FIG. 12 is a diagram showing an example of a slot configuration including a PSCCH symbol with CSI-RS. In this case, for example, the transmission power P CSIRS and the transmission power P of the PSSCH symbol with CSI-RS PSSCH,b may be defined as follows:

number

number

[0059] Here, α may be a value (e.g., a fixed value or a variable) defined in a specification, a parameter that is set (in advance), or a parameter that is specified. P PSSCH,aN may be the transmission power of the PSCCH and PSCCH symbols without CSI-RS, or may be the transmission power of each symbol of the PSCCH and / or PSSCH. CSIRS may be a value based on the amount of CSI-RS resources, for example, the number of CSI-RS resource elements (REs) included in a symbol in a physical resource block (PRB). PSSCH may be a value based on the amount of PSSCH resources, for example, the number of REs of the PSSCH included in a symbol in a PRB.

[0060] In the one-slot period shown in Fig. 12, the total transmission power allocated to each symbol may be maintained at a constant value. In this case, it is assumed that terminal 20 performs an operation such that, for a symbol in which CSI-RS and PSCCH are multiplexed in the frequency domain, the transmission power allocated to CSI-RS is boosted and the power allocated to resource elements of PSCCH other than the CSI-RS is reduced. In this way, by boosting the transmission power of CSI-RS and / or PT-RS, it is possible to improve the accuracy of measurement of channel state information.

[0061] In the above example, since power is allocated to the CSI-RS, the type of the CSI-RS may be a non-zero-power CSI-RS (NZP-CSI-RS).

[0062] The reason why the total transmission power allocated to each symbol in the one slot section shown in FIG. 12 is maintained at a constant value is that if the power is changed in the middle of the one slot section, it takes time for the RF device to change the power, which may cause a problem in the transmission characteristics of the RF device. In order to avoid such a problem, the transmission power between symbols in one slot is kept constant. For example, in FIG. 12, if the total transmission power allocated to one symbol in the part where PSCCH and PSSCH are multiplexed is P, the total transmission power allocated to one symbol in the part of the slot in FIG. 12 where CSI-RS and PSSCH are multiplexed is P. Since the total transmission power allocated to one symbol is constant, when multiple channels are multiplexed in the frequency domain, the total transmission power is allocated to the multiple channels. When it is desired to give priority to a specific channel among multiple channels multiplexed in the frequency domain, it is possible to apply a method of boosting the transmission power of the specific channel more than the transmission power of other channels.

[0063] The above-mentioned CSI-RS may be prohibited from overlapping with the PSCCH at least in the time domain. Similarly, the above-mentioned CSI-RS may be prohibited from overlapping with the DM-RS associated with the PSSCH at least in the time domain. This makes it possible to avoid complicating the formulas related to power control, that is, to simplify the configuration of the terminal.

[0064] Alternatively, the above-mentioned CSI-RS may be allowed to overlap with the PSCCH at least in the time domain. Similarly, the above-mentioned CSI-RS may be allowed to overlap with the DM-RS associated with the PSSCH at least in the time domain. In this case, in one symbol, the transmission power of the CSI-RS may be calculated by a ratio with the transmission power of at least one of the PSSCH, the PSCCH, the PSSCH and / or the DM-RS associated with the PSCCH. By changing the above formula to a formula to be described later, it is possible to boost a signal to be prioritized. In the above example, the CSI-RS may be replaced with the PT-RS.

[0065] As another example, when PSSCH, CSI-RS, and PT-RS are multiplexed in the frequency domain in one symbol, for example, the transmission power P CSIRS , the transmission power of PT-RS P PTRS , the transmission power P PSSCH,c may be defined as follows:

number

number

number

[0066] Here, α may be a value defined by the specification (e.g., a fixed value or a variable), may be a parameter that is set (in advance), or may be a specified parameter. β may be a parameter that is specified by the specification, may be a parameter that is set (in advance), or may be a specified parameter. P PSSCH,a P may be the transmission power of the PSSCH symbol without the PSCCH, CSI-RS and PT-RS, or may be the transmission power of each symbol of the PSCCH and / or PSSCH. PSSCH,cmay be the transmission power of the PSSCH symbol with CSI-RS and PT-RS. CSIRS may be a value based on the amount of CSI-RS resources, for example, the number of CSI-RS resource elements (REs) included in a symbol in a physical resource block (PRB). PTRS may be a value based on the amount of resources of the PT-RS, for example, the number of resource elements (RE) of the PT-RS included in a symbol in a physical resource block (PRB). PSSCH may be a value based on the amount of PSSCH resources, for example, the number of REs of the PSSCH included in a symbol in a PRB.

[0067] As another example, when PSCCH, PSSCH, and CSI-RS are multiplexed in the frequency domain in one symbol, for example, the transmission power P CSIRS , the transmission power of PSCCH P PSCCH , the transmission power P PSSCH,c may be defined as follows:

number

number

number

[0068] Here, α may be a parameter defined by the specifications, may be a parameter that is set (in advance), or may be a specified parameter. β may be a parameter defined by the specifications, may be a parameter that is set (in advance), or may be a specified parameter. P PSSCH,a P may be the transmission power of the PSSCH symbol without the PSCCH, CSI-RS and PT-RS, or may be the transmission power of each symbol of the PSCCH and / or PSSCH.PSSCH,c may be the transmission power of the PSSCH symbol with CSI-RS and PT-RS. CSIRS N may be a value based on the amount of CSI-RS resources, for example, the number of CSI-RS REs included in a symbol in a PRB. PSCCH N may be a value based on the amount of PSCCH resources, for example, the number of REs of the PSSCH included in the symbol in the PRB. PSSCH may be a value based on the amount of PSSCH resources, for example, the number of REs of the PSSCH included in a symbol in a PRB.

[0069] Here, in the case of ZP-CSI-RS (Zero-Power CSI-RS), N CSIRS =0 may also be used.

[0070] (A1-2) Whether or not the terminal 20 boosts the transmission power of the CSI-RS and / or the PT-RS, and the amount of increase in the transmission power of the CSI-RS and / or the amount of increase in the transmission power of the PT-RS (e.g., the value of α and / or the value of β in the formula in A1-1) may be specified by a specification. For example, α=3, β=3. Whether or not the terminal 20 boosts the transmission power of the CSI-RS and / or the PT-RS, and the amount of increase in the transmission power of the CSI-RS and / or the amount of increase in the transmission power of the PT-RS (e.g., the value of α and / or the value of β in the formula in A1-1) may be set (in advance) by the network, for example, or may be set by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling on the sidelink. Furthermore, whether or not the terminal 20 boosts the transmission power of the CSI-RS and / or the PT-RS, and the amount of increase in the transmission power of the CSI-RS and / or the amount of increase in the transmission power of the PT-RS (e.g., the value of α and / or the value of β in the formula in A1-1) may be specified by, for example, Downlink Control Information (DCI) and / or Sidelink Control Information (SCI) for scheduling. For example, a dedicated field for transmission power control may be defined in the DCI / SCI. Also, another field indicating the existence / configuration of the CSI-RS may be defined. Also, whether or not the terminal 20 boosts the transmission power of the CSI-RS and / or the PT-RS, and the amount of increase in the transmission power of the CSI-RS and / or the amount of increase in the transmission power of the PT-RS (e.g., the value of α and / or the value of β in the formula in A1-1) may depend on, for example, the configuration of the CSI-RS and / or the configuration of the PT-RS, and may additionally or alternatively depend on the resources of the CSI-RS and / or the PT-RS. For example, when resources for CSI-RS and / or PT-RS are scarce, the transmission power of CSI-RS and / or PT-RS may be boosted, and when resources for CSI-RS and / or PT-RS are abundant, the transmission power of CSI-RS and / or PT-RS may be set to the same value as the transmission power allocated to the PSSCH.Also, an element indicating whether to boost transmission power may be included in the configuration of the CSI-RS and / or PT-RS. Note that this information may be determined based on higher layer parameters or the like, or may be determined based on a combination of higher layer parameters and DCI and / or SCI.

[0071] (A1-3) The function for calculating the transmission power of the CSI-RS may be a function that does not take into account the value of the transmission power allocated to the PSSCH, other than the maximum transmission power of the terminal 20. Similarly, the function for calculating the transmission power of the PT-RS may be a function that does not take into account the value of the transmission power allocated to the PSSCH, other than the maximum transmission power of the terminal 20. In this case, the transmission power of the CSI-RS is not calculated using a ratio to the value of the transmission power allocated to the PSSCH. Similarly, the transmission power of the PT-RS is not calculated using a ratio to the value of the transmission power allocated to the PSSCH. In this way, by applying Option A1, it is possible to improve the accuracy of acquiring channel state information by boosting the CSI-RS and / or the PT-RS, it is possible to improve the accuracy of the RSRP measurement, and / or it is possible to improve the accuracy of compensating for phase noise.

[0072] (Option A2) The terminal 20 may set the transmission power of the CSI-RS and / or PT-RS associated with the PSSCH to be always equal to the transmission power of the PSSCH. That is, the total transmission power P PSSCH may include the transmission power of the CSI-RS and / or the transmission power of the PT-RS, and may be equally distributed among the REs of the PSSCH data, the REs of the CSI-RS, and / or the REs of the PT-RS. This configuration makes it easier to implement the device, and also makes it possible to reduce changes in specifications.

[0073] The terminal 20 may calculate the transmission power for each transmission opportunity i, for each resource pool, for each subchannel, or for each cast type, such as unicast, groupcast, and broadcast. For example, the transmission power may be determined based on the length of the transmission period of the transmission opportunity i, the size of the resource pool, the subchannel, and the cast type. The transmission power may be determined based on the above formula, regardless of the length of the transmission period of the transmission opportunity i, the size of the resource pool, the subchannel, and the cast type. In the above-mentioned embodiment, the CSI-RS and / or the PT-RS may be replaced with the DM-RS. In the above-mentioned embodiment, the "transmission power" may be replaced with the "transmission power per RE".

[0074] (Assignment B) For NR sidelink groupcast communication, open-loop transmission power control may be performed based on the sidelink path loss.

[0075] FIG. 13 is a diagram showing an example of a case where open-loop transmission power control based on sidelink path loss is performed for NR sidelink groupcast communication. As shown in FIG. 13, by applying open-loop transmission power control based on sidelink, for example, it is possible to control transmission power so that the receiving terminal 20 farthest from the transmitting terminal 20, i.e., the receiving terminal 20 with the largest sidelink path loss value in the group, can receive a radio signal from the transmitting terminal 20. In addition, since the receiving terminal 20 with the largest sidelink path loss value in the group does not set transmission power to a value larger than the transmission power value necessary and sufficient for receiving a radio signal from the transmitting terminal 20, it is possible to reduce interference with other groups. However, as shown in FIG. 13, as the number of terminals 20 in the group increases, more measurement resources and more feedback resources are required accordingly.

[0076] (Proposal B) Conditions for selecting whether to apply open-loop transmission power control based on sidelink path loss to NR sidelink groupcast communication may be specified.

[0077] (Option B1) In NR sidelink groupcast communication, when the RSRPs of all receiving terminals 20 in a group are available to the transmitting terminal 20, the transmitting terminal 20 may apply open-loop transmission power control based on the sidelink pathloss. When the RSRP of at least one receiving terminal 20 among the receiving terminals 20 in a group is not available to the transmitting terminal 20, the transmitting terminal 20 may disable the open-loop transmission power control based on the sidelink pathloss. In this case, open-loop transmission power control based on the downlink pathloss may be applied.

[0078] In addition, the RSRP of the receiving terminal 20 may be made available by the transmitting terminal 20 receiving the RSRP fed back from the receiving terminal 20, or by the transmitting terminal 20 receiving the RS transmitted from the receiving terminal 20 and measuring the RSRP.

[0079] In this way, if the RSRP of at least one receiving terminal 20 is not available to the transmitting terminal 20, at least one receiving terminal 20 may not be able to receive the groupcast communication signal. In this case, open-loop transmission power control based on the sidelink path loss is not effective. According to the method of Option B1, it is possible to apply the open-loop transmission power control based on the sidelink path loss only when the open-loop transmission power control based on the sidelink path loss is effective.

[0080] (Option B2) In NR sidelink groupcast communication, when groupcast Acknowlegement (ACK) / Negative-Acknowledgement (NACK) feedback is enabled, the transmitting terminal 20 may apply open-loop transmission power control based on the sidelink pathloss. When groupcast ACK / NACK feedback is disabled, the transmitting terminal 20 may not apply open-loop transmission power control based on the sidelink pathloss.

[0081] Here, the groupcast Acknowlegement (ACK) / Negative-Acknowledgement (NACK) feedback may mean that the receiving terminal 20 transmits an ACK when the transport block is successfully decoded, and transmits a NACK when the transport block is unsuccessfully decoded. That is, the groupcast ACK / NACK feedback being enabled means that higher reliability is required for communication and / or the number of terminals 20 in the group is small. Therefore, when the groupcast ACK / NACK feedback is enabled, it is assumed that it is desirable to improve the reliability of communication by applying open-loop transmission power control based on the sidelink path loss. When the groupcast ACK / NACK feedback is disabled, it may not be necessary to apply open-loop transmission power control based on the sidelink path loss.

[0082] In addition, in option B2, "groupcast Acknowlegement (ACK) / Negative-Acknowledgement (NACK) feedback" may be replaced with "groupcast HARQ-ACK feedback." The groupcast HARQ-ACK feedback may include at least one of the following two methods. 1. If the decoding of the transport block is successful, the receiving terminal 20 transmits an ACK, and if the decoding of the transport block fails, the receiving terminal 20 transmits a NACK. 2. If the decoding of the transport block is successful, the receiving terminal 20 does not transmit an ACK or a NACK, and if the decoding of the transport block fails, the receiving terminal 20 transmits a NACK.

[0083] (Option B3) In NR sidelink groupcast communication, depending on the number of terminals 20 in the group, the transmitting terminal 20 device may determine whether to apply open-loop transmission power control based on the sidelink path loss. For example, when the number of terminals 20 in the group is smaller than a threshold X (or equal to or smaller than X), the transmitting terminal 20 device may apply open-loop transmission power control based on the sidelink path loss. When the number of terminals 20 in the group is equal to or larger than the threshold X (or larger than X), the transmitting terminal 20 device may not apply open-loop transmission power control based on the sidelink path loss. Here, the threshold X may be specified by a specification, may be set (in advance) by the network, may be set by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink, may be specified or determined based on the configuration of a resource pool, and / or may be specified based on a congestion level.

[0084] Thus, when the number of terminals 20 in a group is small, the measurement resources and feedback resources are small, and in this case, it is assumed that applying open-loop transmission power control based on the sidelink path loss is effective.

[0085] (Option B4) At the 3GPP meeting, a function (distance-based HARQ) that determines whether or not to perform Hybrid Automatic Repeat Request (HARQ) feedback depending on distance-related information (e.g., distance and / or RSRP) is being considered. A receiving terminal 20 that is close in distance to a transmitting terminal 20 performs HARQ feedback. It is assumed that a high reliability is not required for a receiving terminal 20 that is far from the transmitting terminal 20, so the receiving terminal 20 that is far from the transmitting terminal 20 does not need to perform HARQ feedback.

[0086] In NR sidelink groupcast communication, if the RSRP of the receiving terminal 20 performing HARQ feedback is available in the transmitting terminal 20, the transmitting terminal 20 device may apply open-loop transmission power control based on the sidelink path loss. If the RSRP of the receiving terminal 20 performing HARQ feedback is not available in the transmitting terminal 20, the transmitting terminal 20 device may not apply open-loop transmission power control based on the sidelink path loss.

[0087] FIG. 14 is a diagram showing an example of applying open-loop transmission power control based on a sidelink path loss when distance-based HARQ is applied. It is assumed that high reliability of communication is required for the receiving terminal 20 for which HARQ feedback is enabled. Therefore, it is possible to improve the reliability of communication by acquiring the RSRP of the receiving terminal 20 for which HARQ feedback is enabled and then applying open-loop transmission power control based on a sidelink path loss. The RSRP of the receiving terminal 20 may be made available by the transmitting terminal 20 receiving the RSRP fed back from the receiving terminal 20, or by the transmitting terminal 20 receiving the RS transmitted from the receiving terminal 20 and measuring the RSRP. For example, in the above-mentioned distance-based HARQ, when the distance between the transmitting terminal 20 and the receiving terminal 20 is less than (or equal to or less than) a threshold Y, the receiving terminal 20 may enable the HARQ feedback. Here, the threshold Y may be specified by a specification, may be set (in advance) by the network, may be set by a PC5-RRC message sent by another terminal 20, which is RRC signaling in the sidelink, may be specified based on a resource pool setting, and / or may be specified based on a congestion level.

[0088] In this way, according to the Option B4 technique, by applying open-loop transmission power control based on sidelink path loss only to a receiving terminal 20 for which high reliability in communication is required, it is possible to improve the reliability of communication with the receiving terminal 20.

[0089] (Option B5) In NR sidelink groupcast communication, when the RSRPs of all receiving terminals 20 that satisfy the range requirement are usable in the transmitting terminal 20, the transmitting terminal 20 may apply open-loop transmission power control based on the sidelink pathloss. In other cases, the transmitting terminal 20 does not need to apply open-loop transmission power control based on the sidelink pathloss. Note that the RSRP of the receiving terminal 20 may be made usable by the transmitting terminal 20 receiving the RSRP fed back from the receiving terminal 20, or may be made usable by the transmitting terminal 20 receiving the RS transmitted from the receiving terminal 20 and measuring the RSRP.

[0090] In this way, according to the Option B5 technique, by applying open-loop transmission power control based on sidelink path loss only to terminal 20 that is expected to receive groupcast transmissions, it is possible to improve the reliability of communications with that terminal 20.

[0091] (Option B6) At least two of the above-mentioned options B1 to B5 may be combined. For example, when the conditions of options B1 and B2 are met, the transmitting terminal 20 device may apply open-loop transmission power control based on the sidelink path loss. In other cases, the transmitting terminal 20 device may not apply open-loop transmission power control based on the sidelink path loss. Alternatively, for example, when the conditions of option B1 or option B2 are met, the transmitting terminal 20 device may apply open-loop transmission power control based on the sidelink path loss. In other cases, the transmitting terminal 20 device may not apply open-loop transmission power control based on the sidelink path loss.

[0092] By applying any of the above-mentioned options B1 to B6, it becomes possible to perform open-loop transmission power control based on the sidelink path loss in order to improve the reliability of communications. In this case, the transmission power control is applied, but in the case where it is considered that such an approach is not effective, the transmission power control is not applied.

[0093] In Proposal B, RSRP may be replaced with at least one of path loss, RSRQ, and CSI, or may be information related to communication quality between transmitting terminal 20 and receiving terminal 20, but is not limited to this. Furthermore, being able to use RSRP in transmitting terminal 20 may mean that transmitting terminal 20 has received and / or acquired the RSRP and / or any signal for obtaining the RSRP.

[0094] (Assignment C) In NR sidelink communication, when measuring sidelink pathloss, it may be specified which signal is to be used as the reference signal for measuring the pathloss.

[0095] In the case of NR-Uu in Release 15, it is possible to use SS / PBCH block (SSB) and CSI-RS as reference signals for measuring path loss. It is possible to set the ID of SSB or CSI-RS for three information elements, PUCCH-PathlossReferenceRS, PUSCH-PathlossReferenceRS, and pathlossreferenceRS in SRS-ResourceSet, and to receive the reference signal to measure path loss. FIG. 15 is a diagram showing an example of specifying that path loss is measured using a reference signal based on a parameter PUSCH-PathlossReferenceRS of a higher layer. FIG. 16 is a diagram showing an example of a PUSCH-PathlossReferenceRS information element. As shown in FIG. 16, an information element called referenceSignal is included in the PUSCH-PathlossReferenceRS information element, and it is possible to set ssb-Index or csi-RS-Index.

[0096] In NR sidelink communication, a terminal 20 may exist that does not transmit a sidelink SSB. Therefore, in NR sidelink communication, it is not assumed that a sidelink SSB is applied as a reference signal for measuring a sidelink path loss. In addition, in NR sidelink communication, it is not assumed that a terminal 20 transmits a CSI-RS in a standalone manner. In other words, transmission of only the CSI-RS is not permitted, and the CSI-RS is transmitted simultaneously with transmission data, etc.

[0097] (Proposal C) (Option C1) In NR sidelink communications, only the sidelink DM-RS may be available as a reference signal for measuring sidelink pathloss.

[0098] Here, the index or port of the sidelink DM-RS available for measuring the sidelink pathloss may be defined by a specification, may be configured (in advance) as a higher layer parameter or the like, may be configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling on the sidelink, and / or may be specified by the network and / or the other terminal 20. Alternatively, it may be possible to use all DM-RS ports used for sidelink communication for measuring the sidelink pathloss.

[0099] (Option C2) In NR sidelink communication, only the sidelink CSI-RS may be available as a reference signal for measuring sidelink pathloss.

[0100] Here, the sidelink CSI-RS index or port available for performing sidelink pathloss measurement may be defined by a specification, may be configured (pre-configured) by the network, may be configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling on the sidelink, and / or may be designated by the network. Alternatively, it may be possible to use all CSI-RS ports used for sidelink communication for sidelink pathloss measurement.

[0101] (Option C3) In NR sidelink communication, the sidelink DM-RS may be used as a reference signal for measuring sidelink path loss, and additionally the sidelink CSI-RS may be available, where the use of the sidelink CSI-RS may depend on the implementation of the terminal 20.

[0102] Here, the index or port of the sidelink DM-RS available for measuring the sidelink pathloss may be specified by a specification, may be configured (pre-configured) by the network, may be configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling on the sidelink, and / or may be designated by the network. Alternatively, it may be possible to use all DM-RS ports used for sidelink communication for measuring the sidelink pathloss.

[0103] (Option C4) In NR sidelink communication, it is possible to use the sidelink CSI-RS as a reference signal for measuring sidelink pathloss, and additionally, the sidelink DM-RS may be available. Here, the use of the sidelink DM-RS may depend on the implementation of the terminal 20.

[0104] Here, the sidelink CSI-RS index or port available for performing sidelink pathloss measurement may be defined by a specification, may be configured (pre-configured) by the network, may be configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling on the sidelink, and / or may be designated by the network. Alternatively, it may be possible to use all CSI-RS ports used for sidelink communication for sidelink pathloss measurement.

[0105] (Pathloss reference signal (Pathloss reference RS) setting) The sidelink SSB and / or the sidelink CSI-RS and / or the sidelink DM-RS associated with the PSSCH may be defined by a specification as a pathloss reference signal (pathloss reference RS) of the PSCCH / PSSCH / PSFCH transmitted from the transmitting terminal 20 and / or as a pathloss reference signal (pathloss reference RS) of the PSCCH / PSSCH / PSFCH transmitted from the receiving terminal 20, may be configured (in advance) by the network, or may be configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink.

[0106] It is assumed that the path loss reference signal is not specified by the specification, is not (pre-)configured by the network, and is not configured by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink. In this case, the path loss reference signal may be any of the following options Ci to Cv.

[0107] (Option Ci) The DM-RS and / or CSI-RS used for broadcast transmission, or the DM-RS and / or CSI-RS used for sidelink transmission before a PC5-RRC connection is established may be used as the path loss reference signal.

[0108] (Option Cii) All received DM-RS and / or CSI-RS may be used as the path loss reference signal. As a modification of option Cii, for example, the DM-RS and / or CSI-RS transmitted from a specific terminal 20 may be used as the path loss reference signal.

[0109] (Option Ciii) For a sidelink channel, when the TCI state is set (in advance) by the network, when it is set by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink, or when it is specified, the QCL type-A RS and / or QCL type-B RS and / or QCL type-C RS and / or QCL type-D RS associated with the TCI state may be used as a path loss reference signal. Fig. 17 is a diagram showing an example of correspondence between the TCI state and the reference signal.

[0110] (Option Civ) The sidelink path loss based open loop transmission power control may be disabled and / or the downlink open loop transmission power control may be enabled.

[0111] (Option Cv) The path loss reference signal may be the DM-RS and / or CSI-RS specified for L1-RSRP measurements and / or L3-RSRP measurements, the DM-RS and / or CSI-RS configured (in advance) for L1-RSRP measurements and / or L3-RSRP measurements, or the DM-RS and / or CSI-RS configured by a PC5-RRC message for L1-RSRP measurements and / or L3-RSRP measurements.

[0112] (power normalization) When transmitting CSI-RS from multiple antenna ports, for example, when transmitting CSI-RS from two antenna ports, it is assumed that the transmission power of each CSI-RS will be halved. In this case, if RSRP is derived by simply averaging the power, when CSI-RS is transmitted from two antenna ports, the value of each RSRP may be halved. In other words, it may not be possible to accurately calculate the path loss. Therefore, it is assumed that it will be necessary to normalize the power according to the setting of the number of antenna ports, etc.

[0113] (Option Ca) The terminal 20 may measure the RSRP only when the RS is transmitted from a single RS port or when the RS is transmitted from a single CDM group.

[0114] (Option Cb) Provided that the following power normalization is performed, the terminal 20 may measure the RSRP regardless of the number of RS ports. - The calculation of RSRP takes into account the number of RS ports and / or the transmit power from each port. - Case 1: When the number of RS ports is multiple and the total transmit power is the same as that of a single RS port, the instantaneous RSRP P1 may be calculated by summing the RSRP, P2, P3, ... from each RS port. Alternatively, the instantaneous PSPR P1 may be calculated by multiplying the RSRP, P2, from one RS port by the number of RS ports. - Case 2: When there are multiple RS ports, the total transmit power is different from the transmit power in the case of a single RS port, and the difference is ZdB, the instantaneous PSPR P1 may be calculated by subtracting ZdB from the sum of the RSRP, P2, P3, ... from each RS port. Alternatively, the instantaneous PSPR P1 may be calculated by multiplying the RSRP, P2 from one RS port by the number of RS ports and then subtracting ZdB from the result.

[0115] Alternatively, when the number of RS ports for measuring the RSRP is multiple, the total transmission power may be specified (or determined or set) to be always equal to the transmission power from a single RS port.

[0116] (Option Cc) The terminal 20 may measure the RSRP only when the reference signal and the PSSCH data are frequency division multiplexed, or only when the reference signal and the PSSCH data are not frequency division multiplexed.

[0117] (Optional CD) Terminal 20 may measure RSRP regardless of whether the reference signal and the PSSCH data are frequency division multiplexed. When the reference signal and the PSSCH data are frequency division multiplexed, terminal 20 may correct RSRP based on the case where the reference signal is not frequency division multiplexed with the PSSCH data. Alternatively, when the reference signal is not frequency division multiplexed with the PSSCH data, terminal 20 may correct RSRP based on the case where the reference signal is frequency division multiplexed with the PSSCH data.

[0118] In addition, whether or not to frequency-divide the reference signal and the PSSCH data may be specified by a specification, may be set (in advance) by the network, may be set by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink, or may be specified by the DCI and / or SCI.

[0119] Furthermore, in the above-mentioned method of Proposal C, the data of the PSSCH may mean a transport block transmitted on the PSSCH, may mean CSI, or may mean other information transmitted on the PSSCH.

[0120] According to the method of Proposal C described above, it becomes possible for the transmitting terminal 20 to recognize how the receiving terminal 20 is performing the RSRP measurement / calculation, and therefore the transmitting terminal 20 is able to appropriately calculate the path loss.

[0121] In addition, the pathloss reference signal (Pathloss reference RS) may be an L1-RSRP and / or L3-RSRP measurement, a reference signal for measuring L1-RSRP and / or L3-RSRP, a reference signal for measuring pathloss, or a reference signal for open-loop transmission power control.

[0122] (Assignment D) FIG. 18 is a diagram showing examples of two methods for the transmitting terminal 20 to acquire the L3-RSRP measurement result. The transmitting terminal 20 may acquire the L3-RSRP measurement result by transmitting an RS accompanied by PSCCH data (e.g., transport block and / or CSI) to the receiving terminal 20 and acquiring RSRP feedback from the receiving terminal 20. Alternatively, the transmitting terminal 20 may receive an RS accompanied by PSCCH data (e.g., transport block and / or CSI) transmitted from the receiving terminal 20 and calculate the L3-RSRP based on the received RS. In this way, the transmitting terminal 20 can perform open-loop transmission power control based on the L3-RSRP measurement result fed back from the receiving terminal 20, and can also perform open-loop transmission power control based on the L3-RSRP calculated by the transmitting terminal 20. In this way, the transmitting terminal 20 may specify the use of the fed-back L3-RSRP and the L3-RSRP calculated by the transmitting terminal 20 itself. In addition, hereafter, the fed back L3-RSRP may be replaced with an L3-RSRP based on the fed back power information (for example, L1-RSRP).

[0123] (Proposal D) (Option D1) The transmitting terminal 20 may use both the L3-RSRP fed back from the receiving terminal 20 and the L3-RSRP calculated by the transmitting terminal 20 itself. For example, either the L3-RSRP fed back from the receiving terminal 20 or the L3-RSRP calculated by the transmitting terminal 20 itself may be used preferentially.

[0124] For example, when giving priority to the L3-RSRP fed back from the receiving terminal 20, if the transmitting terminal 20 has acquired the L3-RSRP fed back from the receiving terminal 20 and the L3-RSRP calculated by the transmitting terminal 20 itself, the transmitting terminal 20 may use the L3-RSRP fed back from the receiving terminal 20. Also, when giving priority to the L3-RSRP fed back from the receiving terminal 20, if the transmitting terminal 20 has not acquired the L3-RSRP fed back from the receiving terminal 20, the transmitting terminal 20 may use the L3-RSRP calculated by the transmitting terminal 20 itself.

[0125] Alternatively, for example, the transmitting terminal 20 may average the L3-RSRP fed back from the receiving terminal 20 and the L3-RSRP calculated by the transmitting terminal 20 itself. When averaging, weighting may be performed as appropriate. How to use the L3-RSRP fed back from the receiving terminal 20 and the L3-RSRP calculated by the transmitting terminal 20 itself may depend on the implementation of the terminal 20.

[0126] (Option D2) The transmitting terminal 20 may use only the L3-RSRP fed back from the receiving terminal 20. In this case, it may not be assumed that the transmitting terminal 20 uses the L3-RSRP calculated by the transmitting terminal 20 itself for the transmission power control of the transmitting terminal 20 itself.

[0127] (Option D3) The transmitting terminal 20 may use only the L3-RSRP calculated by the transmitting terminal 20 itself. In this case, it may be assumed that the L3-RSRP fed back from the receiving terminal 20 is reported for purposes other than open-loop transmission power control.

[0128] (Option D4) In the specification, at least two of the above-mentioned options 1 to 3 are specified, and any one of the options may be set (in advance) by the network, may be set by a PC5-RRC message transmitted by another terminal 20, which is RRC signaling in the sidelink, or may be specified by the network.

[0129] As in the method of Proposal D, by specifying in the transmitting terminal 20 whether to use the fed-back L3-RSRP or the L3-RSRP calculated by the transmitting terminal 20 itself, the operation of the terminal 20 when performing open-loop transmission power control is clarified.

[0130] (Device configuration) Next, an example of the functional configuration of the base station 10 and the terminal 20 that execute the processing operations described above will be described.

[0131] <Base station 10> Fig. 19 is a diagram showing an example of the functional configuration of the base station 10. As shown in Fig. 19, the base station 10 has a transmitting unit 101, a receiving unit 102, and a control unit 103. The functional configuration shown in Fig. 19 is merely an example. As long as the operation according to the present embodiment can be executed, the functional divisions and the names of the functional units may be any. Note that the transmitting unit 101 may be called a transmitter, and the receiving unit 102 may be called a receiver.

[0132] The transmitter 101 has a function of generating a signal to be transmitted to the terminal 20 and wirelessly transmitting the signal. The receiver 102 has a function of receiving various signals transmitted from the terminal 20 and acquiring, for example, information of a higher layer from the received signal. The receiver 102 also has a function of measuring the received signal and acquiring a quality value.

[0133] The control unit 103 controls the base station 10. Note that the functions of the control unit 103 related to transmission may be included in the transmitting unit 101, and the functions of the control unit 103 related to reception may be included in the receiving unit .

[0134] For example, the control unit 103 of the base station 10 may create parameters to configure the terminal 20 to use only the path loss in the downlink (DL: between the transmitting terminal 20 and the base station 10 (gNB)), only the path loss in the sidelink (SL: between the transmitting terminal 20 and the receiving terminal 20), or both the path loss in the downlink and the path loss in the sidelink for open-loop transmission power control of the NR sidelink, and the transmitting unit 101 may transmit a signal including the command to the terminal 20.

[0135] Also, for example, the control unit 103 of the base station 10 may determine that the terminal 20 should boost the transmission power of the CSI-RS and / or the PT-RS, and set the amount of increase in the transmission power of the CSI-RS and / or the amount of increase in the transmission power of the PT-RS (e.g., the value of α and / or the value of β), and the transmitting unit 101 may transmit a signal including the amount of increase (the value of α and / or the value of β) to the terminal 20.

[0136] Also, for example, the control unit 103 of the base station 10 may set a threshold X for the number of terminals 20 in a group to determine whether or not to apply open-loop transmission power control based on sidelink path loss in NR sidelink groupcast communication, and the transmission unit 101 may transmit a signal including the threshold X to the terminal 20.

[0137] Also, for example, the control unit 103 of the base station 10 may set a port or index of the sidelink DM-RS or CSI-RS that can be used to measure the sidelink pathloss, and the transmission unit 101 may transmit a signal including the port or index to the terminal 20.

[0138] Furthermore, for example, the control unit 103 of the base station 10 may set a sidelink SSB and / or a sidelink CSI-RS and / or a sidelink DM-RS associated with the PSSCH as a pathloss reference signal (pathloss reference RS) of the PSCCH / PSSCH / PSFCH transmitted from the transmitting terminal 20 and / or as a pathloss reference signal (pathloss reference RS) of the PSCCH / PSSCH / PSFCH transmitted from the receiving terminal 20, and the transmitting unit 101 may transmit a signal including the setting information to the terminal 20.

[0139] <Terminal 20> FIG. 20 is a diagram showing an example of a functional configuration of the terminal 20. As shown in FIG. 20, the terminal 20 has a transmitting unit 201, a receiving unit 202, and a control unit 203. The functional configuration shown in FIG. 20 is merely an example. As long as the operation according to this embodiment can be executed, the functional division and the name of the functional unit may be any. Note that the transmitting unit 201 may be called a transmitter, and the receiving unit 202 may be called a receiver. Furthermore, the terminal 20 may be a transmitting terminal 20A or a receiving terminal 20B. Furthermore, the terminal 20 may be a scheduling terminal 20.

[0140] The transmitter 201 creates a transmission signal from transmission data and transmits the transmission signal wirelessly. The receiver 202 wirelessly receives various signals and acquires a higher layer signal from the received physical layer signal. The receiver 202 also includes a function of measuring the received signal and acquiring a quality value.

[0141] The control unit 203 controls the terminal 20. Note that the functions of the control unit 203 related to transmission may be included in the transmitting unit 201, and the functions of the control unit 203 related to reception may be included in the receiving unit 202.

[0142] For example, control unit 203 of terminal 20 may be capable of setting the transmission power value of the CSI-RS associated with the PSSCH to a value different from the transmission power value allocated to the PSCCH. Also, control unit 203 of terminal 20 may be capable of setting the transmission power value of the PT-RS associated with the PSSCH to a value different from the transmission power value allocated to the PSSCH.

[0143] For example, the receiver 202 of the terminal 20 may receive information instructing to boost the transmission power of CSI-RS and / or PT-RS, and information indicating the amount of increase in the transmission power of CSI-RS and / or the amount of increase in the transmission power of PT-RS (e.g., the value of α and / or the value of β), and the control unit 203 may boost the transmission power of CSI-RS and / or PT-RS based on the amount of increase (the value of α and / or the value of β) received by the receiver 202.

[0144] Also, for example, control unit 203 of terminal 20 may set the transmission power of the CSI-RS and / or PT-RS associated with the PSSCH so that it is always the same as the transmission power of the PSSCH.

[0145] Also, for example, the control unit 203 of the terminal 20 may perform open-loop transmission power control based on the sidelink path loss for NR sidelink groupcast communication. Also, for example, the control unit 203 of the terminal 20 may apply open-loop transmission power control based on the sidelink path loss in NR sidelink groupcast communication when the RSRPs of all the receiving terminals 20 in the group are available. Also, for example, the control unit 203 of the terminal 20 may disable the open-loop transmission power control based on the sidelink path loss when the RSRP of at least one receiving terminal 20 among the receiving terminals 20 in the group is unavailable.

[0146] Also, for example, in NR sidelink groupcast communication, when groupcast ACK / NACK feedback is enabled, the control unit 203 of the terminal 20 may apply open-loop transmission power control based on the sidelink pathloss. Also, for example, when groupcast ACK / NACK readback is disabled, the control unit 203 of the terminal 20 may not apply open-loop transmission power control based on the sidelink pathloss.

[0147] Also, for example, in NR sidelink groupcast communication, when the number of terminals 20 in a group is smaller than a threshold value X or is equal to or smaller than the threshold value X, the control unit 203 of the terminal 20 may apply open-loop transmission power control based on the sidelink path loss.

[0148] Furthermore, for example, when distance-based HARQ is applied, if the RSRP of the receiving terminal 20 that must perform HARQ feedback is available, the control unit 203 of the terminal 20 may apply open-loop transmission power control based on the sidelink path loss.

[0149] Also, for example, the control unit 203 of the terminal 20 may select to use at least one of the sidelink DM-RS and the sidelink CSI-RS as a reference signal for measuring sidelink path loss in NR sidelink communication.

[0150] Also, for example, the control unit 203 of the transmitting terminal 20 may select at least one of the L3-RSRP fed back from the receiving terminal 20 and the L3-RSRP calculated by the transmitting terminal 20 itself, and perform open-loop transmission power control.

[0151] <Hardware configuration> The block diagrams (FIGS. 19 and 20) used in the description of the above-mentioned embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. Furthermore, the method of realizing each functional block is not particularly limited. That is, each functional block may be realized by using one device that is physically or logically combined, or may be realized by using two or more devices that are physically or logically separated and directly or indirectly connected (for example, by using wires, wirelessly, etc.). The functional blocks may be realized by combining the one device or the multiple devices with software. Functions include, but are not limited to, judgment, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, selection, establishment, comparison, assumption, expectation, consideration, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocation, mapping, assignment, etc. For example, a functional block (component) that performs the function of transmission is called a transmitting unit or a transmitter. In either case, as described above, there is no particular limitation on the method of realization.

[0152] Also, for example, the terminal 20 and the base station 10 in one embodiment of the present invention may both function as a computer that performs processing according to this embodiment. Fig. 21 is a diagram showing an example of a hardware configuration of the terminal 20 and the base station 10 according to this embodiment. The terminal 20 and the base station 10 described above may each be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

[0153] In the following description, the term "apparatus" can be interpreted as a circuit, a device, a unit, etc. The hardware configuration of the terminal 20 and the base station 10 may be configured to include one or more of the devices indicated by 1001 to 1006 shown in the figure, or may be configured to exclude some of the devices.

[0154] Each function in the terminal 20 and the base station 10 is realized by loading a specific software (program) onto hardware such as a processor 1001 and a memory 1002, causing the processor 1001 to perform calculations, control communications by a communication device 1004, and control at least one of reading and writing of data in the memory 1002 and the storage 1003.

[0155] The processor 1001 controls the entire computer by running, for example, an operating system. The processor 1001 may be configured with a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, a register, and the like.

[0156] Moreover, the processor 1001 reads out a program (program code), a software module, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to the read out programs. As the program, a program that causes a computer to execute at least a part of the operations described in the above-mentioned embodiment is used. For example, the control unit 203 of the terminal 20 may be realized by a control program stored in the memory 1002 and running on the processor 1001, and other functional blocks may be similarly realized. Although the above-mentioned various processes have been described as being executed by one processor 1001, they may be executed simultaneously or sequentially by two or more processors 1001. The processor 1001 may be implemented by one or more chips. The program may be transmitted from a network via a telecommunication line.

[0157] The memory 1002 is a computer-readable recording medium, and may be configured by at least one of, for example, a Read Only Memory (ROM), an Erasable Programmable ROM (EPROM), an Electrically Erasable Programmable ROM (EEPROM), a Random Access Memory (RAM), etc. The memory 1002 may be called a register, a cache, a main memory (primary storage device), etc. The memory 1002 can store a program (program code), software modules, etc. that are executable to implement a wireless communication method according to an embodiment of the present disclosure.

[0158] Storage 1003 is a computer-readable recording medium, and may be composed of at least one of, for example, an optical disk such as a CD-ROM (Compact Disc ROM), a hard disk drive, a flexible disk, a magneto-optical disk (e.g., a compact disk, a digital versatile disk, a Blu-ray (registered trademark) disk), a smart card, a flash memory (e.g., a card, a stick, a key drive), a floppy (registered trademark) disk, a magnetic strip, and the like. Storage 1003 may be referred to as an auxiliary storage device. The above-mentioned storage medium may be, for example, a database, a server, or other suitable medium including at least one of memory 1002 and storage 1003.

[0159] The communication device 1004 is hardware (transmission / reception device) for performing communication between computers via at least one of a wired network and a wireless network, and is also referred to as, for example, a network device, a network controller, a network card, a communication module, etc. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., in order to realize, for example, at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD).

[0160] The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, an LED lamp, etc.) that performs output to the outside. The input device 1005 and the output device 1006 may be integrated into one device (e.g., a touch panel).

[0161] In addition, each device such as the processor 1001 and the memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

[0162] Furthermore, each of the terminal 20 and the base station 10 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), a field programmable gate array (FPGA), etc., and some or all of the functional blocks may be realized by the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

[0163] (Summary of the embodiment) This specification discloses at least the following terminal and communication method.

[0164] A terminal comprising: a control unit that selects a defined or pre-configured sidelink reference signal as a sidelink reference signal usable for measuring a sidelink pathloss, and selects a defined or pre-configured port or index for receiving the selected reference signal; and a receiving unit that receives the reference signal selected by the control unit.

[0165] According to the above configuration, when measuring sidelink path loss in NR sidelink communication, it is possible to select a specified or pre-configured reference signal as a reference signal for measuring the path loss.

[0166] The sidelink reference signal that can be used to measure the sidelink path loss may be at least one of a sidelink demodulation reference signal, a sidelink channel state information estimation reference signal, and a sidelink Synchronization Signal and Physical Broadcast Channel (SS / PBCH) block.

[0167] According to the above configuration, when measuring sidelink path loss in NR sidelink communication, it is possible to select a reference signal specified by a base station or another terminal from among a sidelink demodulation reference signal, a sidelink channel state information estimation reference signal, and a sidelink SSB as a reference signal for measuring the path loss.

[0168] The controller may select, as a sidelink reference signal usable for measuring the sidelink pathloss, any one of the sidelink demodulation reference signal and the sidelink channel state information estimation reference signal, and may select all ports or indexes of the selected sidelink reference signal for measuring the sidelink pathloss.

[0169] According to the above configuration, when measuring sidelink pathloss in NR sidelink communication, it is possible to select sidelink DM-RS or CSI-RS as a reference signal for measuring the pathloss.

[0170] The receiving unit measures the received power by receiving a reference signal selected by the control unit by applying the specified or pre-configured port or index, and the control unit may decide to perform open-loop transmission power control using the received power or to transmit the received power to another terminal.

[0171] According to the above configuration, when the terminal is a transmitting terminal, it is possible to perform open-loop transmission power control using the L3-RSRP calculated by itself, and when the terminal is a receiving terminal, it is possible to feed back the measured L3-RSRP to the transmitting terminal.

[0172] A communication method by a terminal, comprising the steps of: selecting a prescribed or pre-configured sidelink reference signal as a sidelink reference signal usable for measuring a sidelink pathloss, selecting a prescribed or pre-configured port or index for receiving the selected reference signal, and receiving the selected reference signal. According to the above configuration, when measuring a sidelink pathloss in NR sidelink communication, it is possible to select a prescribed or pre-configured reference signal as a reference signal for measuring the pathloss.

[0173] (Supplementary embodiment) Although the embodiment of the present invention has been described above, the disclosed invention is not limited to such an embodiment, and those skilled in the art will understand various modifications, modifications, alternatives, replacements, and the like. Although the description has been given using specific numerical examples to facilitate understanding of the invention, unless otherwise specified, those numerical values ​​are merely examples and any appropriate values ​​may be used. The division of items in the above description is not essential to the present invention, and matters described in two or more items may be used in combination as necessary, and matters described in one item may be applied to matters described in another item (as long as there is no contradiction). The boundaries of functional units or processing units in the functional block diagram do not necessarily correspond to the boundaries of physical parts. The operations of multiple functional units may be physically performed by one part, or the operations of one functional unit may be physically performed by multiple parts. The order of the processing procedures described in the embodiment may be changed as long as there is no contradiction. For convenience of the processing description, the terminal 20 and the base station 10 have been described using functional block diagrams, but such devices may be realized by hardware, software, or a combination thereof. The software operated by the processor of the terminal 20 in accordance with an embodiment of the present invention and the software operated by the processor of the base station 10 in accordance with an embodiment of the present invention may each be stored in random access memory (RAM), flash memory, read only memory (ROM), EPROM, EEPROM, registers, hard disk (HDD), removable disk, CD-ROM, database, server or any other suitable storage medium.

[0174] The notification of information is not limited to the aspects / embodiments described in the present disclosure, and may be performed using other methods. For example, the notification of information may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB))), other signals, or a combination thereof. In addition, the RRC signaling may be called an RRC message, and may be, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, or the like.

[0175] Each aspect / embodiment described in the present disclosure may be applied to at least one of systems using LTE (Long Term Evolution), LTE-A (LTE-Advanced), SUPER 3G, IMT-Advanced, 4G (4th generation mobile communication system), 5G (5th generation mobile communication system), FRA (Future Radio Access), NR (new Radio), W-CDMA (registered trademark), GSM (registered trademark), CDMA2000, UMB (Ultra Mobile Broadband), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, UWB (Ultra-WideBand), Bluetooth (registered trademark), and other suitable systems, and next-generation systems extended based on these. In addition, a combination of multiple systems (e.g., a combination of at least one of LTE and LTE-A and 5G, etc.) may be applied.

[0176] The order of the steps, sequences, flow charts, etc. of each aspect / embodiment described in this disclosure may be changed unless inconsistent. For example, the methods described in this disclosure present elements of various steps using an example order, and are not limited to the particular order presented.

[0177] In the present disclosure, a specific operation performed by the base station 10 may be performed by its upper node in some cases. In a network consisting of one or more network nodes having the base station 10, it is clear that various operations performed for communication with a terminal may be performed by at least one of the base station 10 and other network nodes other than the base station 10 (e.g., MME or S-GW, etc., but are not limited to these). Although the above example illustrates a case in which there is one other network node other than the base station 10, a combination of multiple other network nodes (e.g., MME and S-GW) may also be used.

[0178] The input and output information may be stored in a specific location (e.g., memory) or may be managed using a management table. The input and output information may be overwritten, updated, or added to. The output information may be deleted. The input information may be transmitted to another device.

[0179] The determination may be based on a value represented by a single bit (0 or 1), a Boolean value (true or false), or a numerical comparison (e.g., comparison with a predetermined value).

[0180] Each aspect / embodiment described in this disclosure may be used alone, in combination, or switched according to execution. In addition, notification of specific information (e.g., notification that "X is the case") is not limited to being done explicitly, but may be done implicitly (e.g., not notifying the specific information).

[0181] Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

[0182] Additionally, software, instructions, information, etc. may be transmitted or received over a transmission medium. For example, if the software is transmitted from a website, server, or other remote source using wired and / or wireless technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and / or wireless technologies (such as infrared, microwave, etc.), then these wired and / or wireless technologies are included within the definition of transmission media.

[0183] The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

[0184] In addition, the terms described in this disclosure and the terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, at least one of a channel and a symbol may be a signal (signaling). Also, a signal may be a message.

[0185] The terms "system" and "network" used in this disclosure are used interchangeably. Furthermore, information, parameters, etc. described in this disclosure may be expressed using absolute values, may be expressed using relative values ​​from a predetermined value, or may be expressed using other corresponding information. For example, a radio resource may be indicated by an index.

[0186] The names used for the above-mentioned parameters are not limiting in any way. Moreover, the formulas using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (e.g., PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not limiting in any way.

[0187] In this disclosure, terms such as "base station (BS)", "radio base station", "fixed station", "NodeB", "eNodeB (eNB)", "gNodeB (gNB)", "access point", "transmission point", "reception point", "transmission / reception point", "cell", "sector", "cell group", "carrier", "component carrier", etc. may be used interchangeably. A base station may also be referred to by terms such as a macro cell, a small cell, a femto cell, a pico cell, etc.

[0188] A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire coverage area of ​​the base station can be divided into multiple smaller areas, and each smaller area can also be provided with communication services by a base station subsystem (e.g., a small indoor base station (RRH: Remote Radio Head). The term "cell" or "sector" refers to a part or the entire coverage area of ​​a base station and / or a base station subsystem that provides communication services in this coverage.

[0189] In this disclosure, the terms "Mobile Station (MS)", "user terminal", "User Equipment (UE)", "terminal", etc. may be used interchangeably.

[0190] A mobile station may also be referred to by those skilled in the art as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

[0191] At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a terminal, etc. At least one of the base station and the mobile station may be a device mounted on a moving body, the moving body itself, etc. The moving body may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving body (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). At least one of the base station and the mobile station may include a device that does not necessarily move during communication operation. For example, at least one of the base station and the mobile station may be an IoT (Internet of Things) device such as a sensor.

[0192] Furthermore, the base station in the present disclosure may be read as a user terminal. For example, each aspect / embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between a plurality of user terminals (which may be called, for example, D2D (Device-to-Device) or V2X (Vehicle-to-Everything)). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "side"). For example, an uplink channel, a downlink channel, etc. may be read as a side channel.

[0193] Similarly, the user terminal in the present disclosure may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the user terminal 20 described above.

[0194] The terms "connected," "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "access." As used in this disclosure, two elements may be considered to be "connected" or "coupled" to each other using at least one of one or more wires, cables, and printed electrical connections, as well as electromagnetic energy having wavelengths in the radio frequency range, microwave range, and optical (both visible and invisible) range, as some non-limiting and non-exhaustive examples.

[0195] The reference signal may be abbreviated as RS (Reference Signal) and may be called a pilot depending on the applicable standard.

[0196] As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

[0197] When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Further, when used in this disclosure, the term "or" is not intended to be an exclusive or.

[0198] A radio frame may consist of one or more frames in the time domain. Each of the one or more frames in the time domain may be referred to as a subframe. A subframe may further be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

[0199] Numerology may be a communication parameter that applies to the transmission and / or reception of a signal or channel, such as SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame structure, a particular filtering operation performed by the transceiver in the frequency domain, a particular windowing operation performed by the transceiver in the time domain, etc.

[0200] A slot may be composed of one or more symbols (such as an Orthogonal Frequency Division Multiplexing (OFDM) symbol, a Single Carrier Frequency Division Multiple Access (SC-FDMA) symbol, etc.) in the time domain. A slot may be a time unit based on numerology.

[0201] A slot may include multiple minislots. Each minislot may be composed of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may be composed of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (or PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (or PUSCH) mapping type B.

[0202] A radio frame, a subframe, a slot, a minislot, and a symbol each represent a time unit for transmitting a signal. The radio frame, the subframe, the slot, the minislot, and the symbol may each be referred to by a different name.

[0203] For example, one subframe may be called a transmission time interval (TTI), multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. That is, at least one of the subframe and the TTI may be a subframe (1 ms) in the existing LTE, a period shorter than 1 ms (for example, 1-13 symbols), or a period longer than 1 ms. Note that the unit expressing the TTI may be called a slot, a minislot, or the like, instead of a subframe.

[0204] Here, TTI refers to, for example, the minimum time unit for scheduling in wireless communication. For example, in an LTE system, a base station performs scheduling to allocate radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) to each user terminal in TTI units. Note that the definition of TTI is not limited to this.

[0205] The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) in which a transport block, a code block, a code word, etc. are actually mapped may be shorter than the TTI.

[0206] In addition, when one slot or one minislot is called TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit of scheduling. Also, the number of slots (minislots) constituting the minimum time unit of scheduling may be controlled.

[0207] A TTI having a time length of 1 ms may be called a normal TTI (TTI in LTE Rel. 8-12), a normal TTI, a long TTI, a normal subframe, a normal subframe, a long subframe, a slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, a short TTI, a partial or fractional TTI, a shortened subframe, a short subframe, a minislot, a subslot, a slot, etc.

[0208] In addition, a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length exceeding 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

[0209] A resource block (RB) is a resource allocation unit in the time domain and the frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of the numerology, for example, 12. The number of subcarriers included in an RB may be determined based on the numerology.

[0210] In addition, the time domain of the RB may include one or more symbols and may be one slot, one minislot, one subframe, or one TTI in length. Each of one TTI, one subframe, etc. may be composed of one or more resource blocks.

[0211] Note that one or more RBs may be called a physical resource block (PRB), a sub-carrier group (SCG), a resource element group (REG), a PRB pair, an RB pair, or the like.

[0212] Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource region of one subcarrier and one symbol.

[0213] A Bandwidth Part (BWP), which may also be referred to as a fractional bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a numerology on a carrier, where the common RBs may be identified by the index of the RBs relative to a common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

[0214] The BWP may include a BWP for UL (UL BWP) and a BWP for DL ​​(DL BWP). One or more BWPs may be configured for a UE within one carrier.

[0215] At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal / channel outside the active BWP. Note that the terms "cell", "carrier", etc. in this disclosure may be replaced with "BWP".

[0216] The above-mentioned structures of radio frames, subframes, slots, minislots, symbols, etc. are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, the number of symbols in a TTI, the symbol length, the cyclic prefix (CP) length, etc. may be changed in various ways.

[0217] In this disclosure, where articles have been added due to translation, such as, for example, a, an, and the in English, the disclosure may include that the nouns following these articles are in the plural form.

[0218] In the present disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "coupled" may also be interpreted in the same way as "different."

[0219] Although the present invention has been described in detail above, it is clear to those skilled in the art that the present invention is not limited to the embodiments described in this specification. The present invention can be implemented in modified and altered forms without departing from the spirit and scope of the present invention as defined by the claims. Therefore, the description in this specification is intended to be illustrative and does not have any limiting meaning on the present invention. [Explanation of symbols]

[0220] 10 base station 20 Terminals 101 Transmitter 102 Receiving unit 103 Control section 201 Transmitter 202 Receiving unit 203 Control Unit 1001 Processor 1002 Memory 1003 Storage 1004 Communication equipment 1005 Input Device 1006 Output device

Claims

1. a receiver that receives a sidelink demodulation reference signal from another terminal via a DMRS port, the sidelink demodulation reference signal being used for measuring a sidelink path loss; a control unit that designates a DMRS port for receiving the demodulation reference signal by using control information received from the other terminal; Equipped with The receiver receives the sidelink demodulation reference signal via a sidelink data channel, and calculates a transmission power of the sidelink data channel for each transmission opportunity of the sidelink data channel. Terminal.

2. a transmitter configured to transmit a sidelink demodulation reference signal used for measuring a sidelink path loss to a second terminal via a DMRS port; a control unit that specifies a DMRS port for receiving the demodulation reference signal in control information to be transmitted to the second terminal; A first terminal comprising: a receiver configured to receive the sidelink demodulation reference signal from a first terminal via the DMRS port; a control unit that designates the DMRS port that receives the demodulation reference signal by using the control information received from the first terminal; Equipped with The receiver receives the sidelink demodulation reference signal via a sidelink data channel, and calculates a transmission power of the sidelink data channel for each transmission opportunity of the sidelink data channel. A second terminal; and A communication system comprising:

3. receiving a sidelink demodulation reference signal from another terminal at a DMRS port, the sidelink demodulation reference signal being used for measuring a sidelink path loss; specifying a DMRS port for receiving the demodulation reference signal by using control information received from the other terminal; Equipped with The receiving step includes receiving the sidelink demodulation reference signal via a sidelink data channel, and calculating a transmission power of the sidelink data channel for each transmission opportunity of the sidelink data channel. The communication method of the device.

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