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WO2018190623A1 - Procédé et appareil de transmission d'un signal de liaison latérale dans un système de communication sans fil - Google Patents

Procédé et appareil de transmission d'un signal de liaison latérale dans un système de communication sans fil Download PDF

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Publication number
WO2018190623A1
WO2018190623A1 PCT/KR2018/004212 KR2018004212W WO2018190623A1 WO 2018190623 A1 WO2018190623 A1 WO 2018190623A1 KR 2018004212 W KR2018004212 W KR 2018004212W WO 2018190623 A1 WO2018190623 A1 WO 2018190623A1
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Prior art keywords
pscch
pssch
power
transmission
signal
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PCT/KR2018/004212
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English (en)
Korean (ko)
Inventor
채혁진
서한별
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엘지전자 주식회사
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Application filed by 엘지전자 주식회사 filed Critical 엘지전자 주식회사
Priority to EP18784062.4A priority Critical patent/EP3611856B1/fr
Priority to JP2020504085A priority patent/JP6902156B2/ja
Priority to US16/604,082 priority patent/US10959194B2/en
Priority to KR1020197033308A priority patent/KR20190137873A/ko
Priority to CN201880038132.XA priority patent/CN110720187B/zh
Publication of WO2018190623A1 publication Critical patent/WO2018190623A1/fr

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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L1/00Arrangements for detecting or preventing errors in the information received
    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04WWIRELESS COMMUNICATION NETWORKS
    • H04W52/00Power management, e.g. Transmission Power Control [TPC] or power classes
    • H04W52/04Transmission power control [TPC]
    • H04W52/30Transmission power control [TPC] using constraints in the total amount of available transmission power
    • H04W52/36Transmission power control [TPC] using constraints in the total amount of available transmission power with a discrete range or set of values, e.g. step size, ramping or offsets

Definitions

  • the following description relates to a wireless communication system, and more particularly, to a method and apparatus for determining transmission power and transmitting side link signals when using high MCS.
  • Wireless communication systems are widely deployed to provide various kinds of communication services such as voice and data.
  • a wireless communication system is a multiple access system capable of supporting communication with multiple users by sharing available system resources (bandwidth, transmission power, etc.).
  • multiple access systems include code division multiple access (CDMA) systems, frequency division multiple access (FDMA) systems, time division multiple access (TDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, and single carrier frequency (SC-FDMA).
  • CDMA code division multiple access
  • FDMA frequency division multiple access
  • TDMA time division multiple access
  • OFDMA orthogonal frequency division multiple access
  • SC-FDMA single carrier frequency division multiple access
  • MCD division multiple access
  • MCDMA multi-carrier frequency division multiple access
  • MC-FDMA multi-carrier frequency division multiple access
  • D2D communication is a method of establishing a direct link between user equipments (UEs), and directly communicating voice and data between evolved NodeBs (eNBs).
  • the D2D communication may include a scheme such as UE-to-UE communication, peer-to-peer communication, and the like.
  • the D2D communication scheme may be applied to machine-to-machine (M2M) communication, machine type communication (MTC), and the like.
  • M2M machine-to-machine
  • MTC machine type communication
  • D2D communication has been considered as a way to solve the burden on the base station due to the rapidly increasing data traffic.
  • the D2D communication unlike the conventional wireless communication system, since the data is exchanged between devices without passing through a base station, the network can be overloaded.
  • the D2D communication it is possible to expect the effect of reducing the procedure of the base station, the power consumption of the devices participating in the D2D, increase the data transmission speed, increase the capacity of the network, load balancing, cell coverage expansion.
  • V2X vehicle to everything
  • FDM frequency-division multiplexing
  • a method of transmitting a sidelink signal by a terminal in a wireless communication system comprising: determining transmission power of a physical sidelink control channel (PSCCH) and a physical sidelink shared channel (PSSCH); And transmitting a PSCCH and a PSSCH at the determined transmission power, wherein the PSCCH and the PSSCH are transmitted by frequency division multiplexing (FDM) in one subframe, and are subjected to a modulation and coding scheme (MCS) or a modulation order (Modulation).
  • FDM frequency division multiplexing
  • MCS modulation and coding scheme
  • Modulation Modulation
  • An embodiment of the present invention provides a terminal apparatus for transmitting a sidelink signal in a wireless communication system, comprising: a transmitting apparatus and a receiving apparatus; And a processor, wherein the processor determines transmission power of the PSCCH and the PSSCH, transmits the PSCCH and the PSSCH at the determined transmission power through the transmission apparatus, and the PSCCH and the PSSCH are FDM in one subframe.
  • the terminal apparatus does not apply a power offset value for increasing transmission power when determining PSCCH transmission power.
  • the preset value may be 64 QAM.
  • the PSCCH may have a resource block (RB) size.
  • RB resource block
  • At least a part of the available power may be allocated to increase the transmit power of the PSSCH because the power offset value is not applied when determining the PSCCH transmit power.
  • the magnitude of the power offset may be set according to whether the PSCCH and the PSSCH are continuously transmitted on a frequency axis.
  • the PSCCH and the PSSCH may be transmitted in different subframes.
  • an AGC interval equal to or greater than a preset value may be used.
  • EVM error vector magnitude
  • 1 is a diagram illustrating a structure of a radio frame.
  • FIG. 2 is a diagram illustrating a resource grid in a downlink slot.
  • 3 is a diagram illustrating a structure of a downlink subframe.
  • FIG. 4 is a diagram illustrating a structure of an uplink subframe.
  • FIG. 5 is a configuration diagram of a wireless communication system having multiple antennas.
  • FIG. 6 shows a subframe in which the D2D synchronization signal is transmitted.
  • FIG. 7 is a diagram for explaining a relay of a D2D signal.
  • FIG. 8 shows an example of a D2D resource pool for D2D communication.
  • FIG. 13 is a diagram illustrating a configuration of a transmitting and receiving device.
  • each component or feature may be considered to be optional unless otherwise stated.
  • Each component or feature may be embodied in a form that is not combined with other components or features.
  • some components and / or features may be combined to form an embodiment of the present invention.
  • the order of the operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment.
  • the base station has a meaning as a terminal node of the network that directly communicates with the terminal.
  • the specific operation described as performed by the base station in this document may be performed by an upper node of the base station in some cases.
  • a 'base station (BS)' may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point (AP), and the like.
  • the repeater may be replaced by terms such as relay node (RN) and relay station (RS).
  • the term “terminal” may be replaced with terms such as a user equipment (UE), a mobile station (MS), a mobile subscriber station (MSS), a subscriber station (SS), and the like.
  • a base station may also be used as a meaning of a scheduling node or a cluster header. If the base station or the relay also transmits a signal transmitted by the terminal, it can be regarded as a kind of terminal.
  • the cell names described below are applied to transmission and reception points such as a base station (eNB), a sector, a remote radio head (RRH), a relay, and the like. It may be used as a generic term for identifying a component carrier.
  • eNB base station
  • RRH remote radio head
  • Embodiments of the present invention may be supported by standard documents disclosed in at least one of the wireless access systems IEEE 802 system, 3GPP system, 3GPP LTE and LTE-Advanced (LTE-A) system and 3GPP2 system. That is, steps or parts which are not described to clearly reveal the technical spirit of the present invention among the embodiments of the present invention may be supported by the above documents. In addition, all terms disclosed in the present document can be described by the above standard document.
  • CDMA code division multiple access
  • FDMA frequency division multiple access
  • TDMA time division multiple access
  • OFDMA orthogonal frequency division multiple access
  • SC-FDMA single carrier frequency division multiple access
  • CDMA may be implemented with a radio technology such as Universal Terrestrial Radio Access (UTRA) or CDMA2000.
  • TDMA may be implemented with wireless technologies such as Global System for Mobile communications (GSM) / General Packet Radio Service (GPRS) / Enhanced Data Rates for GSM Evolution (EDGE).
  • GSM Global System for Mobile communications
  • GPRS General Packet Radio Service
  • EDGE Enhanced Data Rates for GSM Evolution
  • OFDMA may be implemented in a wireless technology such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA).
  • UTRA is part of the Universal Mobile Telecommunications System (UMTS).
  • 3rd Generation Partnership Project (3GPP) long term evolution (LTE) is part of an Evolved UMTS (E-UMTS) using E-UTRA, and employs OFDMA in downlink and SC-FDMA in uplink.
  • LTE-A Advanced
  • WiMAX can be described by the IEEE 802.16e standard (WirelessMAN-OFDMA Reference System) and the advanced IEEE 802.16m standard (WirelessMAN-OFDMA Advanced system). For clarity, the following description focuses on 3GPP LTE and 3GPP LTE-A systems, but the technical spirit of the present invention is not limited thereto.
  • a structure of a radio frame will be described with reference to FIG. 1.
  • uplink / downlink data packet transmission is performed in units of subframes, and one subframe is defined as a predetermined time interval including a plurality of OFDM symbols.
  • the 3GPP LTE standard supports a type 1 radio frame structure applicable to frequency division duplex (FDD) and a type 2 radio frame structure applicable to time division duplex (TDD).
  • the downlink radio frame consists of 10 subframes, and one subframe consists of two slots in the time domain.
  • the time it takes for one subframe to be transmitted is called a transmission time interval (TTI).
  • TTI transmission time interval
  • one subframe may have a length of 1 ms and one slot may have a length of 0.5 ms.
  • One slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain.
  • RBs resource blocks
  • a resource block (RB) is a resource allocation unit and may include a plurality of consecutive subcarriers in one block.
  • the number of OFDM symbols included in one slot may vary depending on the configuration of a cyclic prefix (CP).
  • CP has an extended CP (normal CP) and a normal CP (normal CP).
  • normal CP normal CP
  • the number of OFDM symbols included in one slot may be seven.
  • the OFDM symbol is configured by an extended CP, since the length of one OFDM symbol is increased, the number of OFDM symbols included in one slot is smaller than that of the normal CP.
  • the number of OFDM symbols included in one slot may be six. If the channel state is unstable, such as when the terminal moves at a high speed, an extended CP may be used to further reduce intersymbol interference.
  • one subframe includes 14 OFDM symbols.
  • the first two or three OFDM symbols of each subframe may be allocated to a physical downlink control channel (PDCCH), and the remaining OFDM symbols may be allocated to a physical downlink shared channel (PDSCH).
  • PDCCH physical downlink control channel
  • PDSCH physical downlink shared channel
  • Type 2 radio frames consist of two half frames, each of which has five subframes, a downlink pilot time slot (DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS).
  • DwPTS downlink pilot time slot
  • GP guard period
  • UpPTS uplink pilot time slot
  • One subframe consists of two slots.
  • DwPTS is used for initial cell search, synchronization or channel estimation at the terminal.
  • UpPTS is used for channel estimation at the base station and synchronization of uplink transmission of the terminal.
  • the guard period is a period for removing interference generated in the uplink due to the multipath delay of the downlink signal between the uplink and the downlink.
  • one subframe consists of two slots regardless of the radio frame type.
  • the structure of the radio frame is only an example, and the number of subframes included in the radio frame or the number of slots included in the subframe and the number of symbols included in the slot may be variously changed.
  • FIG. 2 is a diagram illustrating a resource grid in a downlink slot.
  • One downlink slot includes seven OFDM symbols in the time domain and one resource block (RB) is shown to include 12 subcarriers in the frequency domain, but the present invention is not limited thereto.
  • one slot includes 7 OFDM symbols in the case of a general cyclic prefix (CP), but one slot may include 6 OFDM symbols in the case of an extended-CP (CP).
  • Each element on the resource grid is called a resource element.
  • One resource block includes 12 ⁇ 7 resource elements.
  • the number N DL of resource blocks included in the downlink slot depends on the downlink transmission bandwidth.
  • the structure of the uplink slot may be the same as the structure of the downlink slot.
  • FIG. 3 is a diagram illustrating a structure of a downlink subframe.
  • Up to three OFDM symbols at the front of the first slot in one subframe correspond to a control region to which a control channel is allocated.
  • the remaining OFDM symbols correspond to data regions to which a Physical Downlink Shared Channel (PDSCH) is allocated.
  • Downlink control channels used in the 3GPP LTE / LTE-A system include, for example, a Physical Control Format Indicator Channel (PCFICH), a Physical Downlink Control Channel (PDCCH), Physical Hybrid Automatic Repeat Request Indicator Channel (PHICH).
  • PCFICH Physical Control Format Indicator Channel
  • PDCH Physical Downlink Control Channel
  • PHICH Physical Hybrid Automatic Repeat Request Indicator Channel
  • the PHICH includes a HARQ ACK / NACK signal as a response of uplink transmission.
  • Control information transmitted through the PDCCH is referred to as downlink control information (DCI).
  • the DCI includes uplink or downlink scheduling information or an uplink transmit power control command for a certain terminal group.
  • the PDCCH is a resource allocation and transmission format of the downlink shared channel (DL-SCH), resource allocation information of the uplink shared channel (UL-SCH), paging information of the paging channel (PCH), system information on the DL-SCH, on the PDSCH Resource allocation of upper layer control messages such as random access responses transmitted to the network, a set of transmit power control commands for individual terminals in an arbitrary terminal group, transmission power control information, and activation of voice over IP (VoIP) And the like.
  • a plurality of PDCCHs may be transmitted in the control region.
  • the terminal may monitor the plurality of PDCCHs.
  • the PDCCH is transmitted in an aggregation of one or more consecutive Control Channel Elements (CCEs).
  • CCEs Control Channel Elements
  • CCE is a logical allocation unit used to provide a PDCCH at a coding rate based on the state of a radio channel.
  • the CCE corresponds to a plurality of resource element groups.
  • the number of CCEs required for the PDCCH may vary depending on the size and coding rate of the DCI. For example, any one of 1, 2, 4, and 8 CCEs (corresponding to PDCCH formats 0, 1, 2, and 3, respectively) may be used for PDCCH transmission, and when the size of DCI is large and / or channel state If a low coding rate is required due to poor quality, a relatively large number of CCEs may be used for one PDCCH transmission.
  • the base station determines the PDCCH format in consideration of the size of the DCI transmitted to the terminal, the cell bandwidth, the number of downlink antenna ports, the PHICH resource amount, and adds a cyclic redundancy check (CRC) to the control information.
  • the CRC is masked with an identifier called a Radio Network Temporary Identifier (RNTI) according to the owner or purpose of the PDCCH.
  • RNTI Radio Network Temporary Identifier
  • the PDCCH is for a specific terminal, the cell-RNTI (C-RNTI) identifier of the terminal may be masked to the CRC.
  • a paging indicator identifier P-RNTI
  • SI-RNTI system information identifier and system information RNTI
  • RA-RNTI Random Access-RNTI
  • the uplink subframe may be divided into a control region and a data region in the frequency domain.
  • a physical uplink control channel (PUCCH) including uplink control information is allocated to the control region.
  • a physical uplink shared channel (PUSCH) including user data is allocated.
  • PUCCH physical uplink control channel
  • PUSCH physical uplink shared channel
  • one UE does not simultaneously transmit a PUCCH and a PUSCH.
  • PUCCH for one UE is allocated to an RB pair in a subframe. Resource blocks belonging to a resource block pair occupy different subcarriers for two slots. This is called a resource block pair allocated to the PUCCH is frequency-hopped at the slot boundary.
  • the transmitted packet is transmitted through a wireless channel
  • signal distortion may occur during the transmission process.
  • the distortion In order to correctly receive the distorted signal at the receiving end, the distortion must be corrected in the received signal using the channel information.
  • a method of transmitting the signal known to both the transmitting side and the receiving side and finding the channel information with the distortion degree when the signal is received through the channel is mainly used.
  • the signal is called a pilot signal or a reference signal.
  • the reference signal may be divided into an uplink reference signal and a downlink reference signal.
  • an uplink reference signal as an uplink reference signal,
  • DM-RS Demodulation-Reference Signal
  • SRS sounding reference signal
  • DM-RS Demodulation-Reference Signal
  • CSI-RS Channel State Information Reference Signal
  • MBSFN Multimedia Broadcast Single Frequency Network
  • Reference signals can be classified into two types according to their purpose. There is a reference signal for obtaining channel information and a reference signal used for data demodulation. Since the former has a purpose for the UE to acquire channel information on the downlink, the UE should be transmitted over a wide band, and the UE should receive the reference signal even if the UE does not receive the downlink data in a specific subframe. It is also used in situations such as handover.
  • the latter is a reference signal transmitted together with a corresponding resource when the base station transmits a downlink, and the terminal can demodulate data by performing channel measurement by receiving the reference signal. This reference signal should be transmitted in the area where data is transmitted.
  • FIG. 5 is a configuration diagram of a wireless communication system having multiple antennas.
  • the transmission rate can be improved and the frequency efficiency can be significantly improved.
  • the transmission rate may theoretically increase as the rate of increase rate Ri multiplied by the maximum transmission rate Ro when using a single antenna.
  • a transmission rate four times higher than a single antenna system may be theoretically obtained. Since the theoretical capacity increase of multi-antenna systems was proved in the mid 90's, various techniques to actively lead to the actual data rate improvement have been actively studied. In addition, some technologies are already being reflected in various wireless communication standards such as 3G mobile communication and next generation WLAN.
  • the research trends related to multi-antennas to date include the study of information theory aspects related to the calculation of multi-antenna communication capacity in various channel environments and multi-access environments, the study of wireless channel measurement and model derivation of multi-antenna systems, improvement of transmission reliability, and improvement of transmission rate. Research is being actively conducted from various viewpoints, such as research on space-time signal processing technology.
  • the communication method in a multi-antenna system will be described in more detail using mathematical modeling. It is assumed that there are Nt transmit antennas and Nt receive antennas in the system.
  • the transmission signal when there are Nt transmit antennas, the maximum information that can be transmitted is NT.
  • the transmission information may be expressed as follows.
  • Each transmission information The transmit power may be different.
  • Each transmit power In this case, the transmission information whose transmission power is adjusted may be expressed as follows.
  • Weighting matrix Nt transmitted signals actually applied by applying Consider the case where is configured.
  • Weighting matrix Plays a role in properly distributing transmission information to each antenna according to a transmission channel situation.
  • Vector It can be expressed as follows.
  • Received signal is received signal of each antenna when there are Nr receiving antennas Can be expressed as a vector as
  • channels may be divided according to transmit / receive antenna indexes. From the transmit antenna j to the channel through the receive antenna i It is indicated by. Note that in the order of the index, the receiving antenna index is first, and the index of the transmitting antenna is later.
  • FIG. 5 (b) shows a channel from NR transmit antennas to receive antenna i .
  • the channels may be bundled and displayed in vector and matrix form.
  • a channel arriving from a total of NT transmit antennas to a receive antenna i may be represented as follows.
  • AWGN Additive White Gaussian Noise
  • the received signal may be expressed as follows through the above-described mathematical modeling.
  • the channel matrix indicating the channel state The number of rows and columns of is determined by the number of transmit and receive antennas.
  • Channel matrix The number of rows is equal to the number of receiving antennas NR, and the number of columns is equal to the number of transmitting antennas Nt. That is, the channel matrix The matrix is NR ⁇ Nt.
  • the rank of a matrix is defined as the minimum number of rows or columns that are independent of each other. Thus, the rank of the matrix cannot be greater than the number of rows or columns.
  • Channel matrix Rank of ( ) Is limited to
  • rank may be defined as the number of nonzero eigenvalues when the matrix is eigenvalue decomposition.
  • another definition of rank may be defined as the number of nonzero singular values when singular value decomposition is performed.
  • rank in the channel matrix The physical meaning of is the maximum number of different information that can be sent on a given channel.
  • 'rank' for MIMO transmission refers to the number of paths that can independently transmit signals at specific time points and specific frequency resources, and 'number of layers' denotes each path. It indicates the number of signal streams transmitted through the system. In general, since the transmitting end transmits the number of layers corresponding to the number of ranks used for signal transmission, unless otherwise specified, the rank has the same meaning as the number of layers.
  • some nodes may transmit a D2D signal (where the node may be referred to as an eNB, a UE, a synchronization reference node or a synchronization source), and transmit a D2D synchronization signal (D2DSS, D2D Synchronization Signal).
  • a method of transmitting and receiving signals in synchronization with the remaining terminals may be used.
  • the D2D synchronization signal may include a primary synchronization signal (Primary D2DSS or Primary Sidelink synchronization signal (PDSSDS)) and a secondary synchronization signal (Secondary D2DSS or Secondary Sidelink synchronization signal (SSSS)). It may be a Zadoff-chu sequence or a similar / modified / repeated structure to the PSS, etc. It is also possible to use other Zadoff Chu root indices (eg, 26, 37) unlike the DL PSS. May be a similar / modified / repeated structure to M-sequence or SSS, etc.
  • PDSSDS Primary Sidelink synchronization signal
  • SSSS Secondary Sidelink synchronization signal
  • PD2DSS Physical D2D synchronization channel
  • SRN becomes eNB
  • D2DSS becomes PSS / SSS
  • PD2DSS The / SD2DSS follows the UL subcarrier mapping scheme, and the subframe through which the D2D synchronization signal is transmitted is shown in Fig. 6.
  • the PD2DSCH Physical D2D synchronization channel
  • the PD2DSCH may be transmitted on the same subframe as the D2DSS or on a subsequent subframe DMRS may be used for demodulation of the PD2DSCH.
  • the SRN may be a node transmitting a D2DSS and a Physical D2D Synchronization Channel (PD2DSCH).
  • the D2DSS may be in the form of a specific sequence
  • the PD2DSCH may be in the form of a sequence representing specific information or a code word after a predetermined channel coding.
  • the SRN may be an eNB or a specific D2D terminal.
  • the UE may be an SRN.
  • the D2DSS may be relayed for D2D communication with an out of coverage terminal.
  • the D2DSS can be relayed over multiple hops.
  • relaying a synchronization signal is a concept including not only directly relaying a synchronization signal of a base station, but also transmitting a D2D synchronization signal of a separate format in accordance with the timing of receiving the synchronization signal. As such, since the D2D synchronization signal is relayed, the in-coverage terminal and the out-of-coverage terminal can directly perform communication.
  • a UE refers to a network equipment such as a base station that transmits and receives a signal according to a terminal or a D2D communication scheme.
  • the terminal may select a resource unit corresponding to a specific resource in a resource pool representing a set of resources and transmit a D2D signal using the corresponding resource unit.
  • the receiving terminal UE2 may be configured with a resource pool in which UE1 can transmit a signal, and detect a signal of UE1 in the corresponding pool.
  • the resource pool may be notified by the base station when UE1 is in the connection range of the base station.
  • a resource pool is composed of a plurality of resource units, each terminal may select one or a plurality of resource units and use them for transmitting their D2D signals.
  • the resource unit may be as illustrated in FIG. 8 (b). Referring to FIG. 8 (b), it can be seen that total frequency resources are divided into NFs and total time resources are divided into NTs so that a total of NF * NT resource units are defined.
  • the resource pool may be repeated every NT subframe. In particular, one resource unit may appear periodically and repeatedly as shown.
  • a resource pool may mean a set of resource units that can be used for transmission by a terminal that wants to transmit a D2D signal.
  • Resource pools can be divided into several types. First, they may be classified according to contents of D2D signals transmitted from each resource pool. For example, the contents of the D2D signal may be divided, and a separate resource pool may be configured for each. As the content of the D2D signal, there may be a scheduling assignment or a physical sidelink control chanel (PSCCH), a D2D data channel, and a discovery channel.
  • the SA includes information such as the location of resources used for transmission of the D2D data channel which is transmitted by the transmitting terminal and other information such as MCS (modulation and coding scheme), MIMO transmission method, and timing advance (TA) necessary for demodulation of the data channel. It may be a signal.
  • MCS modulation and coding scheme
  • MIMO transmission method MIMO transmission method
  • TA timing advance
  • This signal may be transmitted multiplexed with D2D data on the same resource unit.
  • the SA resource pool may mean a pool of resources in which an SA is multiplexed with D2D data and transmitted. Another name may be referred to as a D2D control channel or a physical sidelink control channel (PSCCH).
  • the D2D data channel (or physical sidelink shared channel (PSSCH)) may be a pool of resources used by a transmitting terminal to transmit user data. If the SA is multiplexed and transmitted together with the D2D data on the same resource unit, only the D2D data channel having the form except for the SA information may be transmitted in the resource pool for the D2D data channel.
  • the REs used to transmit SA information on individual resource units in the SA resource pool can still be used to transmit D2D data in the D2D data channel resource pool.
  • the discovery channel may be a resource pool for a message that allows a transmitting terminal to transmit information such as its ID so that the neighboring terminal can discover itself.
  • the transmission timing determination method of the D2D signal for example, is it transmitted at the time of reception of a synchronization reference signal or is transmitted by applying a constant TA there
  • a resource allocation method for example, For example, whether an eNB assigns transmission resources of an individual signal to an individual transmitting UE or whether an individual transmitting UE selects an individual signaling resource on its own in a pool, and a signal format (for example, each D2D signal occupies one subframe).
  • the number of symbols, the number of subframes used for transmission of one D2D signal), the signal strength from the eNB, and the transmission power strength of the D2D UE may be further divided into different resource pools.
  • Mode 1 a transmission resource region is set in advance, or the eNB designates a transmission resource region, and the UE directly selects a transmission resource in a method of directly instructing the eNB to transmit resources of the D2D transmitting UE in D2D communication.
  • Mode 2 In the case of D2D discovery, when the eNB directly indicates a resource, a type 2 when a UE directly selects a transmission resource in a preset resource region or a resource region indicated by the eNB is called Type 1.
  • the mode 1 terminal may transmit an SA (or a D2D control signal, Sidelink Control Information (SCI)) through a resource configured from the base station.
  • SA or a D2D control signal, Sidelink Control Information (SCI)
  • SCI Sidelink Control Information
  • the mode 2 terminal is configured with a resource to be used for D2D transmission from the base station.
  • the SA may be transmitted by selecting a time frequency resource from the configured resource.
  • the first SA period may be started in a subframe away from a specific system frame by a predetermined offset SAOffsetIndicator indicated by higher layer signaling.
  • Each SA period may include a SA resource pool and a subframe pool for D2D data transmission.
  • the SA resource pool may include the last subframe of the subframes indicated by which the SA is transmitted in the subframe bitmap (saSubframeBitmap) from the first subframe of the SA period.
  • a subframe used for actual data transmission may be determined by applying a time-resource pattern for transmission or a time-resource pattern (TRP).
  • the T-RPT may be repeatedly applied, and the last applied T-RPT is the number of remaining subframes. As long as it is truncated, it can be applied.
  • the transmitting terminal transmits at the position where the T-RPT bitmap is 1 in the indicated T-RPT, and one MAC PDU transmits four times.
  • a periodic message type CAM (Cooperative Awareness Message) message, an event triggered message type DENM message, or the like may be transmitted.
  • the CAM may include basic vehicle information such as dynamic state information of the vehicle such as direction and speed, vehicle static data such as dimensions, exterior lighting state, and route details.
  • the size of the CAM message may be 50-300 bytes.
  • the CAM message is broadcast and the latency must be less than 100ms.
  • the DENM may be a message generated in a sudden situation such as a vehicle breakdown or accident.
  • the size of the DENM can be less than 3000 bytes, and any vehicle within the transmission range can receive the message.
  • the DENM may have a higher priority than the CAM, and in this case, having a high priority may mean transmitting a higher priority when a simultaneous transmission occurs from one UE perspective, or priority among a plurality of messages. May attempt to send a higher message in time priority. In many UEs, a higher priority message may be less interference than a lower priority message, thereby reducing the probability of reception error. In the case of a security overhead, CAM can have a larger message size than otherwise.
  • NR next-generation radio access technology
  • a self-contained structure may include all of a DL control channel, DL or UL data, and UL control channel in one frame unit.
  • DL data scheduling information and UL data scheduling information may be transmitted in the DL control channel
  • ACK / NACK information, CSI information (modulation and coding scheme information, MIMO transmission related information, etc.) for the DL data may be transmitted in the UL control channel.
  • CSI information modulation and coding scheme information, MIMO transmission related information, etc.
  • scheduling request, etc. may be transmitted.
  • some of the DL control / DL data / UL data / UL control in one frame may not be configured.
  • the order of channels constituting one frame may vary. (For example, DL control / DL data / UL control / UL data or UL control / UL data / DL control / DL data, etc.)
  • a terminal may determine the transmission power of the PSCCH and PSSCH, and may transmit the PSCCH and PSSCH at the determined transmission power.
  • the PSCCH and the PSSCH are transmitted by being FDM in one subframe, and the MCS or the modulation order is greater than or equal to a preset value, a power offset value for increasing transmission power may not be applied when determining the PSCCH transmission power.
  • the terminal sets differently whether or not the power power offset of the control signal is applied according to the MCS or the modulation order.
  • a power offset value for reducing transmission power is applied when determining the PSCCH transmission power (minus PSCCH power offset).
  • a power offset value for increasing transmit power of less than or equal to a preset value may be applied. That is, the terminal sets the power power offset value differently between the control signal and the data signal according to the MCS or the modulation order.
  • At least a part of the available power may be allocated to increase the transmit power of the PSSCH because the power offset value is not applied when determining the PSCCH transmit power. That is, when the PSCCH and the PSSCH are transmitted by FDM and a high MCS / modulation order is used, the transmission power of the PSSCH rather than the PSCCH is boosted.
  • the preset value may be 64 QAM.
  • the power offset of the control signal (power or power spectrum density (PS) value additionally allocated to the control signal based on the data signal) is 1 dB or It can be set below that (eg 0dB). This is to set the power offset differently to the control signal in order to effectively receive the data signal above the specific MCS (to reduce the distortion).
  • the terminal uses 64QAM (or more than a certain modulation order) may not apply the power offset of the control signal (for example, PSCCH).
  • PSCCH control signal
  • This method is to reduce the distortion of the data signal when receiving a high MCS like the above-described method.
  • the SNR required for successful decoding of the data signal and the control signal is significantly different, it may be meaningless to apply a power offset to the control signal. (In certain SNR, the control signal continues to decode, and the data may continue to fail decoding.) Therefore, to improve the decoding performance of the data, a specific MCS is used to increase the SNR of the data rather than allocating additional power to the control signal.
  • power offset may not be applied to PSCCH or deboosting (minus PSCCH power offset).
  • BLER block error rate
  • the environment used for the simulation is EVA 180 channel model, Frequency offset 1200Hz, Single transmission (single Tx), PSSCH RB size: 3, PSCCH RB size: 2 (note: fixed in 3GPP TS36.211), MCS level: MCS21 / 22/23 (note: MCSs corresponding to 64QAM), TBS (Transport block size) scaling factor: 0.7 (note: symbols considering DMRS, AGC, and Tx / Rx switching added to sidelink mode 3/4 in the current TBS table. Taking into account the TBS table multiplied by 0.7).
  • giving a 0 dB power offset satisfies BLER 0.1 in the case of a specific SNR (AA) in the MCS21, as compared with giving a 3 dB power offset to the PSCCH. That is, giving a 0 dB power offset to the PSCCH is more effective for PSSCH decoding than giving a 3 dB power offset to the PSCCH.
  • as much power as possible can be allocated to the data to balance the SNR of the control signal and the data signal.
  • power boosting of the PSCCH may not be applied over a specific MCS / modulation.
  • a method of applying power deboosting or power boosting to the PSSCH rather than a specific MCS / modulation order is proposed.
  • a power offset (boosting or deboosting) value used for each MCS or modulation may be predetermined or signaled to the terminal by a network.
  • the PSCCH and the PSSCH may be transmitted in different subframes. That is, the terminal sets the subframe offset between the control signal and the data signal differently according to the MCS or the modulation order. If the terminal uses 64QAM (or a predetermined modulation order), the subframe offset of the control signal and the data signal is set to be greater than 0 so that the control signal and the data signal are always TDM. In this case, the subframe offset may be previously determined by the network or may be a value signaled by the transmitting terminal to the neighboring terminal through a control signal. In this way, signal distortion caused by simultaneous transmission of a control signal and a data signal in a specific MCS or a specific modulation order can be avoided. In addition, excessive MPR application can be avoided, thereby reducing the coverage reduction of the data signal.
  • existing terminals may not decode and sense data resources by considering a reserved bit as a control signal that is not properly decoded when a reserved bit is set to a value other than a predetermined value (for example, all zero).
  • the reserved bit can be interpreted only by the terminals of the new release, and the terminals perform decoding and sensing (PSSCH RSRP measurement) of the data signal at the subframe offset indicated by the reserved bit.
  • a separate control signal resource region and / or a data signal resource region may be set (by a network configured in this physical layer or higher layer signal or in advance) for a terminal using a specific MCS or a specific modulation order or more.
  • a separate PSCCH resource region may be configured for a terminal using 64 QAM (or a predetermined modulation order).
  • an AGC interval equal to or greater than a preset value may be used. Specifically, a longer AGC period may be needed to decode above a specific MCS or above a specific modulation order.
  • the following methods can be considered.
  • N symbols at the beginning of a subframe may be mapped to comb type. (If data is not mapped to the odd-numbered RE, the unmapped RE may be puncturing or rate matching.)
  • N may be a predetermined value or may be set differently according to MCS. This is to perform a more accurate and faster AGC in the receiver by transmitting a symbol of a repeating form, and to use the remaining symbol interval for data decoding when performing the AGC in more than one symbol interval.
  • the above descriptions are not limited only to direct communication between terminals, and may be used in uplink or downlink, where a base station or a relay node may use the proposed method.
  • examples of the proposed scheme described above may also be regarded as a kind of proposed schemes as they may be included as one of the implementation methods of the present invention.
  • the above-described proposed schemes may be independently implemented, some proposed schemes may be implemented in a combination (or merge) form.
  • Information on whether the proposed methods are applied is informed by the base station through a predefined signal (for example, a physical layer signal or a higher layer signal) to the terminal or received by the transmitting terminal. Rules may be defined to signal to the terminal or to request that the receiving terminal requests the transmitting terminal.
  • whether the PSCCH power boosting may be signaled by the network to the UE as this physical layer or higher layer signal.
  • Such signaling may be configured separately for each resource region or may be applied to all terminals participating in direct communication between terminals. If 64QAM is used, whether the PSCCH power offset is applied may be signaled or preconfigured by the network as a higher layer signal to the UE.
  • FIG. 13 is a diagram showing the configuration of a transmission point apparatus and a terminal apparatus according to an embodiment of the present invention.
  • the transmission point apparatus 10 may include a receiver 11, a transmitter 12, a processor 13, a memory 14, and a plurality of antennas 15. .
  • the plurality of antennas 15 refers to a transmission point apparatus that supports MIMO transmission and reception.
  • the reception device 11 may receive various signals, data, and information on the uplink from the terminal.
  • the transmitter 12 may transmit various signals, data, and information on downlink to the terminal.
  • the processor 13 may control the overall operation of the transmission point apparatus 10.
  • the processor 13 of the transmission point apparatus 10 may process matters necessary in the above-described embodiments.
  • the processor 13 of the transmission point apparatus 10 performs a function of processing the information received by the transmission point apparatus 10, information to be transmitted to the outside, and the memory 14 stores the calculated information and the like. It may be stored for a predetermined time and may be replaced by a component such as a buffer (not shown).
  • the terminal device 20 may include a receiver 21, a transmitter 22, a processor 23, a memory 24, and a plurality of antennas 25. have.
  • the plurality of antennas 25 refers to a terminal device that supports MIMO transmission and reception.
  • the receiving device 21 may receive various signals, data, and information on downlink from the base station.
  • the transmitter 22 may transmit various signals, data, and information on the uplink to the base station.
  • the processor 23 may control operations of the entire terminal device 20.
  • the processor 23 of the terminal device 20 may process matters necessary in the above-described embodiments. Specifically, the processor determines the transmission power of the PSCCH and PSSCH, and transmits the PSCCH and PSSCH at the determined transmission power through the transmission device, the PSCCH and the PSSCH is FDM transmitted in one subframe, When the MCS or the modulation order is greater than or equal to a preset value, the power offset value for increasing the transmission power may not be applied when determining the PSCCH transmission power.
  • the processor 23 of the terminal device 20 performs a function of processing the information received by the terminal device 20, information to be transmitted to the outside, etc., and the memory 24 stores the calculated information and the like for a predetermined time. And may be replaced by a component such as a buffer (not shown).
  • the description of the transmission point apparatus 10 may be equally applicable to a relay apparatus as a downlink transmission entity or an uplink reception entity, and the description of the terminal device 20 is a downlink. The same may be applied to a relay apparatus as a receiving subject or an uplink transmitting subject.
  • Embodiments of the present invention described above may be implemented through various means.
  • embodiments of the present invention may be implemented by hardware, firmware, software, or a combination thereof.
  • a method according to embodiments of the present invention may include one or more Application Specific Integrated Circuits (ASICs), Digital Signal Processors (DSPs), Digital Signal Processing Devices (DSPDs), and Programmable Logic Devices (PLDs). It may be implemented by field programmable gate arrays (FPGAs), processors, controllers, microcontrollers, microprocessors, and the like.
  • ASICs Application Specific Integrated Circuits
  • DSPs Digital Signal Processors
  • DSPDs Digital Signal Processing Devices
  • PLDs Programmable Logic Devices
  • FPGAs field programmable gate arrays
  • processors controllers, microcontrollers, microprocessors, and the like.
  • the method according to the embodiments of the present invention may be implemented in the form of an apparatus, procedure, or function for performing the above-described functions or operations.
  • the software code may be stored in a memory unit and driven by a processor.
  • the memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.
  • Embodiments of the present invention as described above may be applied to various mobile communication systems.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

Un mode de réalisation de la présente invention concerne un procédé de transmission d'un signal de liaison latérale par un terminal dans un système de communication sans fil, et le procédé comprend : une étape de détermination d'une puissance de transmission d'un canal de commande de liaison latérale physique (PSCCH) et d'un canal partagé de liaison latérale physique (PSSCH) ; et une étape de transmission du PSCCH et du PSSCH avec la puissance de transmission déterminée, le PSCCH et le PSSCH étant multiplexés par répartition en fréquence (FDM) dans une sous-trame et transmis, et lorsqu'un schéma de modulation et de codage (MCS) ou un ordre de modulation est supérieur ou égal à une valeur prédéfinie, la valeur de décalage de puissance pour augmenter la puissance de transmission n'est pas appliquée lors de la détermination de la puissance de transmission de PSCCH.
PCT/KR2018/004212 2017-04-10 2018-04-10 Procédé et appareil de transmission d'un signal de liaison latérale dans un système de communication sans fil WO2018190623A1 (fr)

Priority Applications (5)

Application Number Priority Date Filing Date Title
EP18784062.4A EP3611856B1 (fr) 2017-04-10 2018-04-10 Procédé et appareil de transmission d'un signal de liaison latérale dans un système de communication sans fil
JP2020504085A JP6902156B2 (ja) 2017-04-10 2018-04-10 無線通信システムにおいてサイドリンク信号を送信する方法及び装置
US16/604,082 US10959194B2 (en) 2017-04-10 2018-04-10 Method and apparatus for transmitting sidelink signal in wireless communication system
KR1020197033308A KR20190137873A (ko) 2017-04-10 2018-04-10 무선 통신 시스템에서 사이드링크 신호를 전송하는 방법 및 장치
CN201880038132.XA CN110720187B (zh) 2017-04-10 2018-04-10 在无线通信系统中发送副链路信号的方法和设备

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US201762483882P 2017-04-10 2017-04-10
US62/483,882 2017-04-10
US201762502609P 2017-05-06 2017-05-06
US62/502,609 2017-05-06
KR20180039450 2018-04-05
KR10-2018-0039450 2018-04-05

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CN113196856A (zh) * 2018-12-27 2021-07-30 株式会社Ntt都科摩 通信装置及通信方法
CN113678517A (zh) * 2019-04-08 2021-11-19 苹果公司 用于pscch覆盖增强的nr v2x侧链路结构
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CN113796142A (zh) * 2019-05-02 2021-12-14 三星电子株式会社 在无线通信系统中发送和接收旁路控制信息的方法和装置
EP4014581A4 (fr) * 2019-08-16 2023-09-27 Telefonaktiebolaget Lm Ericsson (Publ) Commande de puissance pour canal de commande de liaison latérale
CN114450910A (zh) * 2019-09-27 2022-05-06 Lg 电子株式会社 无线通信系统中sci传输相关的ue的操作方法
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CN114616897A (zh) * 2019-11-01 2022-06-10 高通股份有限公司 动态物理侧链路控制信道增益

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