KR20200130222A - Method and apparatus for transmitting and receiving channel state information reference signal in full dimension mimo wireless communication system - Google Patents

Abstract

The present invention relates to a method and apparatus for transmitting or receiving a channel state information reference signal (CSI-RS) in a wireless communication system supporting full dimension multi-input multi-output (FD-MIMO). According to an aspect of the present invention, a method of transmitting a CSI-RS by a base station in a wireless communication system may comprise the steps of: transmitting, to a terminal, information indicating the number of CSI-RS antenna ports M (M>=2), and resource allocation information for each group of a CSI-RS resource consisting of aggregation of K (K>=2) groups; mapping a CSI-RS corresponding to the M CSI-RS antenna ports on the CSI-RS resource; and transmitting the mapped CSI-RS to the terminal.

Description

Method and device for transmitting/receiving channel status information reference signal in a full-dimensional multi-input multiple-output wireless communication system

The present invention relates to a wireless communication system, and more specifically, a method, apparatus, software, or a recording medium in which the software is stored for transmitting or receiving a channel state information reference signal in a wireless communication system supporting full-dimensional multiple input multiple output. For.

Multi-Input Multi-Output (MIMO) technology is a technology that improves the transmission and reception efficiency of data by using multiple transmission antennas and multiple reception antennas by breaking away from the use of one transmission antenna and one reception antenna. . When a single antenna is used, the receiving end receives data through a single antenna path, but when multiple antennas are used, the receiving end receives data through multiple paths. Accordingly, it is possible to improve the data transmission speed and the amount of transmission, and to increase the coverage.

In order to increase the multiplexing gain of the MIMO operation, channel status information (CSI) is fed back from the MIMO receiving end and used at the MIMO transmitting end. This may be referred to as a closed-loop (CL)-MIMO operation. The receiving end may determine CSI by performing channel measurement using a predetermined reference signal (RS) from the transmitting end. The CSI may include a rank indicator (RI), a precoding matrix index (PMI), and channel quality information (CQI).

In the case of transmitting and receiving data using multiple antennas, the correct signal can be received only by knowing the channel condition between each transmitting antenna and receiving antenna. Therefore, a separate reference signal must exist for each antenna port. In the 3GPP LTE/LTE-A system, various reference signals are defined. For example, in a system according to 3GPP LTE releases-8 and 9, a CRS (Cell-Specific RS) transmitted every subframe over a broadband, a UE-specific reference signal (UE-Specific RS) used for data demodulation, etc. Has been defined. In addition, in the system after 3GPP LTE-A Release-10, as new reference signals to support up to 8 antenna ports in downlink, CSI-RS, data or EPDCCH (Enhanced Physical Downlink Control Channel) demodulation for channel measurement is performed. For DM-RS (DeModulation-RS) and the like were further defined.

In such an existing MIMO wireless communication system, only one-dimensional antenna array (eg, ULA (Uniform Linear Array) or cross-polar (Cross-Pole or X-Pol)) was supported. Formed by such a one-dimensional antenna array The direction of the beam is specified only in the azimuth angle direction (e.g., horizontal domain), and cannot be specified in the elevation angle direction (e.g., vertical domain), so only 2-dimensional beamforming. Could be supported.

Recently, a wireless communication system supporting a two-dimensional antenna array has been developed for the purpose of improving system performance. Such a wireless communication system may also be referred to as a Full Dimension MIMO (FD-MIMO) wireless communication system. The two-dimensional antenna array may support more than eight antenna ports in downlink. The direction of the beam formed by the two-dimensional antenna array can be specified in an azimuth direction and an elevation direction, thereby enabling 3-dimensional beamforming. However, the CSI-RS supporting the antenna configuration considering FD-MIMO has not yet been defined.

Accordingly, there is a need for a specific scheme for a CSI-RS design supporting an antenna configuration in consideration of FD-MIMO (eg, supporting more than 8 antenna ports).

The present invention provides a method and apparatus for resource allocation and antenna port configuration of CSI-RS supporting new antenna configuration considering FD-MIMO.

The present invention provides a method and an apparatus for signaling configuration information for a CSI-RS supporting a new antenna configuration considering FD-MIMO to a terminal.

The present invention provides a method and apparatus for channel estimation and CSI feedback in a terminal based on CSI-RS supporting a new antenna configuration considering FD-MIMO.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems that are not mentioned will be clearly understood by those of ordinary skill in the technical field to which the present invention belongs from the following description. I will be able to.

According to an aspect of the present invention, a method of transmitting a channel state information-reference signal (CSI-RS) by a base station in a wireless communication system may be provided. The method includes information indicating the number of CSI-RS antenna ports M (M≥2), and resources for each group of CSI-RS resources consisting of aggregation of K (K≥2) groups Transmitting allocation information to the terminal; Mapping CSI-RSs corresponding to the M CSI-RS antenna ports on the CSI-RS resource; And transmitting the mapped CSI-RS to the terminal.

According to another aspect of the present invention, a method of transmitting channel state information (CSI) by a terminal in a wireless communication system may be provided. The method includes: channel state information-information indicating the number of antenna ports M (M≥2) of the reference signal (CSI-RS), and CSI- consisting of aggregation of K (K≥2) groups. Receiving resource allocation information for each group of RS resources from a base station; Receiving a CSI-RS corresponding to the M CSI-RS antenna ports mapped on the CSI-RS resource from the base station; And transmitting the CSI generated based on the CSI-RS to the base station.

According to another aspect of the present invention, a base station apparatus for transmitting a channel state information-reference signal (CSI-RS) in a wireless communication system may be provided. The base station apparatus includes a processor; And a transceiver. The processor is a resource for each group of CSI-RS resources consisting of information indicating the number of CSI-RS antenna ports M (M≥2) and aggregation of K (K≥2) groups CSI-RS-related configuration information determining unit for generating allocation information; And a CSI-RS resource mapping unit for mapping CSI-RSs corresponding to the M CSI-RS antenna ports on the CSI-RS resource, wherein the processor uses the transceiver to obtain the mapped CSI-RS. It can be set to transmit to the terminal.

According to another aspect of the present invention, a terminal device for transmitting channel state information (CSI) in a wireless communication system may be provided. The terminal device includes a processor; And a transceiver. The processor includes information indicating the number of antenna ports M (M≥2) of the channel state information-reference signal (CSI-RS) based on signaling from the base station, and a combination of K (K≥2) groups ( aggregation) CSI-RS-related configuration information determining unit for determining resource allocation information for each group of CSI-RS resources; A CSI-RS reception processor configured to receive a CSI-RS corresponding to the M CSI-RS antenna ports mapped on the CSI-RS resource from the base station; And it may include a CSI report transmitter for transmitting the CSI generated based on the CSI-RS to the base station.

In the aspects of the present invention, the CSI-RS resource composed of a combination of the K groups may be defined within one and the same subframe.

In the above aspects of the present invention, M may have a value greater than 8.

In the aspects of the present invention, when K=2, the CSI-RS resource is composed of a combination of the CSI-RS resource of the first group and the CSI-RS resource of the second group, and the CSI of the first group Resource allocation information for -RS resources and resource allocation information for CSI-RS resources of the second group may be signaled separately from each other.

In the aspects of the present invention, among the M CSI-RS antenna ports, some of the antenna ports correspond to the CSI-RS resources of the first group, and the remaining part of the CSI-RS resources of the second group. The antenna port may correspond.

In the aspects of the present invention, the number of antenna ports corresponding to the CSI-RS resources of the first and second groups may be the same.

In the aspects of the present invention, when M=16, some eight antenna ports correspond to the CSI-RS resources of the first group, and the remaining eight antenna ports correspond to the CSI-RS resources of the second group. Can correspond.

In the aspects of the present invention, the information indicating the number M of the CSI-RS antenna ports corresponds to a combination of information indicating the number K of the groups and information indicating the number of antenna ports in one group. can do.

In the aspects of the present invention, the resource allocation information for the CSI-RS resource may have a size proportional to K.

The features briefly summarized above with respect to the present invention are merely exemplary aspects of the detailed description of the present invention described below, and do not limit the scope of the present invention.

According to the present invention, a CSI-RS resource allocation and antenna port configuration method supporting a new antenna configuration considering FD-MIMO may be provided.

According to the present invention, a method of signaling configuration information on a CSI-RS supporting a new antenna configuration considering FD-MIMO to a terminal may be provided.

According to the present invention, a channel estimation and CSI feedback scheme in a terminal based on a CSI-RS supporting a new antenna configuration considering FD-MIMO may be provided.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned can be clearly understood by those of ordinary skill in the art from the following description. will be.

The drawings appended to the present specification are provided to provide an understanding of the present invention, and are intended to illustrate various embodiments of the present invention and to explain the principles of the present invention together with the description of the specification.
1 is a diagram showing the configuration of a wireless device according to the present invention.
2 and 3 are diagrams for explaining the structure of a radio frame in a 3GPP LTE system.
4 is a diagram illustrating a structure of a downlink subframe.
5 is a diagram showing the structure of an uplink subframe.
6 and 7 are diagrams for explaining resource mapping of CSI-RS.
8 is a diagram illustrating a multi-antenna system according to an example of the present invention.
9 is a diagram illustrating an FD MIMO transmission scheme according to an example of the present invention.
10 is a diagram for explaining a CSI-RS-related operation for supporting FD-MIMO according to the present invention.
11 is a diagram for explaining a CSI-RS-related operation for supporting FD-MIMO according to an example of the present invention.
12 is a diagram illustrating a configuration of a processor according to the present invention.

Hereinafter, in the present specification, contents related to the present invention will be described in detail through exemplary drawings and examples. In adding reference numerals to constituent elements in each drawing, it should be noted that the same constituent elements are given the same reference numerals as much as possible even though they are indicated on different drawings. In addition, in describing an embodiment of the present specification, if it is determined that a detailed description of a related known configuration or function may obscure the subject matter of the present specification, a detailed description thereof will be omitted.

In addition, the present specification is described for a wireless communication network, and the operation performed in the wireless communication network is performed in the process of controlling the network and transmitting or receiving signals in a system (for example, a base station) that controls the wireless communication network, or This can be done in the process of transmitting or receiving a signal in a terminal coupled to the corresponding wireless network.

That is, it is apparent that various operations performed for communication with a terminal in a network comprising a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. The'base station (BS)' may be replaced by terms such as a fixed station, Node B, eNode B (eNB), and access point (AP). In addition,'terminal' will be replaced by terms such as UE (User Equipment), MS (Mobile Station), MSS (Mobile Subscriber Station), SS (Subscriber Station), and non-AP STA. I can.

Terms used to describe embodiments of the present invention may be described by 3GPP LTE/LTE-A (LTE-Advanced) standard documents, except for a case where it is specified to be used in a different meaning. However, it should be noted that this is only for economy and clarity of description, and embodiments of the present invention are not limited to being applied only to a system conforming to 3GPP LTE/LTE-A or a subsequent standard thereof.

Hereinafter, a wireless device according to the present invention will be described.

1 is a diagram showing the configuration of a wireless device according to the present invention.

FIG. 1 shows a terminal device 100 corresponding to an example of a downlink reception device or an uplink transmission device, and a base station device 200 corresponding to an example of a downlink transmission device or an uplink reception device.

The terminal device 100 may include a processor 110, an antenna unit 120, a transceiver 130, and a memory 140.

The processor 110 performs baseband-related signal processing and may include an upper layer processing unit 111 and a physical layer processing unit 112. The upper layer processor 111 may process an operation of a medium access control (MAC) layer, a radio resource control (RRC) layer, or a higher layer. The physical layer processing unit 112 may process an operation of the physical (PHY) layer (eg, uplink transmission signal processing, downlink reception signal processing). In addition to performing baseband-related signal processing, the processor 110 may control the overall operation of the terminal device 100.

The antenna unit 120 may include one or more physical antennas, and may support MIMO transmission/reception when including a plurality of antennas. The transceiver 130 may include a radio frequency (RF) transmitter and an RF receiver. The memory 140 may store information processed by the processor 110, software related to the operation of the terminal device 100, an operating system, and an application, and may include components such as a buffer.

The base station apparatus 200 may include a processor 210, an antenna unit 220, a transceiver 230, and a memory 240.

The processor 210 performs baseband-related signal processing and may include an upper layer processing unit 211 and a physical layer processing unit 212. The upper layer processing unit 211 may process an operation of the MAC layer, the RRC layer, or higher layers. The physical layer processing unit 212 may process an operation of the PHY layer (eg, downlink transmission signal processing and uplink reception signal processing). In addition to performing baseband-related signal processing, the processor 210 may control the overall operation of the base station apparatus 200.

The antenna unit 220 may include one or more physical antennas, and may support MIMO transmission/reception when including a plurality of antennas. The transceiver 230 may include an RF transmitter and an RF receiver. The memory 240 may store information processed by the processor 210, software related to the operation of the base station apparatus 200, an operating system, and an application, and may include components such as a buffer.

Hereinafter, a radio frame structure will be described.

2 and 3 are diagrams for explaining the structure of a radio frame in a 3GPP LTE system.

In a cellular wireless packet communication system, uplink or downlink transmission is performed on a subframe basis. One subframe is defined as a predetermined time interval including a plurality of 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).

2 is a diagram showing the structure of a type 1 radio frame. One radio frame consists of 10 subframes, and one subframe consists of 2 slots in a time domain. The time taken for one subframe to be transmitted is referred to as a transmission time interval (TTI). For example, the length of one subframe is 1 ms, and the length of one slot is 0.5 ms. One slot may include a plurality of symbols in the time domain. The symbol may be an Orthogonal Frequency Division Multiplexing (OFDM) symbol in downlink and a Single Carrier-Frequency Division Multiple Access (SC-FDMA) symbol in uplink, but is not limited thereto. The number of symbols included in one slot may vary according to the CP (Cyclic Prefix) setting. CP includes an extended CP and a normal CP. For example, in the case of a normal CP, the number of symbols included in one slot may be seven. In the case of the extended CP, since the length of one symbol is increased, the number of symbols included in one slot may be 6, which is less than that in the case of a normal CP. When the channel state is unstable, such as when the cell size is large or the terminal moves at a high speed, an extended CP may be used to further reduce inter-symbol interference.

In FIG. 2, a normal CP is assumed in the resource grid, and one slot corresponds to 7 symbols in the time domain. In the frequency domain, the system bandwidth is defined as an integer (N) times of a resource block (RB), the downlink system bandwidth is N ^DL , and the uplink system bandwidth may be indicated by a parameter of N ^UL . A resource block is a resource allocation unit, and may correspond to a plurality (eg, 7) symbols corresponding to one slot in the time domain and a plurality (eg, 12) consecutive subcarriers in the frequency domain. Each element on the resource grid is called a resource element (RE). One resource block includes 12×7 resource elements. The resource grid of FIG. 2 can be applied equally to an uplink slot and a downlink slot. In addition, the resource grid of FIG. 2 can be applied equally to the slot of the type 1 radio frame and the slot of the type 2 radio frame to be described later.

3 is a diagram showing the structure of a type 2 radio frame. Type 2 radio frame consists of 2 half frames, each half frame has 5 subframes, DwPTS (Downlink Pilot Time Slot), Guard Period (GP), UpPTS (Uplink Pilot Time Slot) It can be composed of. Like the type 1 radio frame, one subframe consists of two slots. In addition to data transmission and reception, DwPTS is used for initial cell search, synchronization, or channel estimation in the terminal. UpPTS is used for channel estimation at the base station and synchronization of uplink transmission of the terminal. The guard interval (GP) is an interval for removing interference occurring in uplink due to a multipath delay of a downlink signal between uplink and downlink. DwPTS, GP, and UpPTS may also be referred to as special subframes.

4 is a diagram illustrating a structure of a downlink subframe. In one subframe, a plurality of (eg, three) OFDM symbols in the front part of the first slot correspond to a control region to which a control channel is allocated. The remaining OFDM symbols correspond to a data region to which a physical downlink shared channel (PDSCH) is allocated. The downlink control channels used in the 3GPP LTE system include a Physical Control Format Indicator Channel (PCFICH), a Physical Downlink Control Channel (PDCCH), and a physical HARQ indicator channel (Physical Hybrid automatic channel). repeat request indicator channel, PHICH), etc. Additionally, an enhanced physical downlink control channel (EPDCCH) in the data region may also be transmitted to terminals configured by the base station.

The PCFICH is transmitted in the first OFDM symbol of a subframe and includes information on the number of OFDM symbols used for control channel transmission in the subframe.

The PHICH includes HARQ-ACK information as a response of uplink transmission.

(E) Control information transmitted through the PDCCH is referred to as downlink control information (DCI). The DCI includes uplink or downlink scheduling information, or other control information according to various purposes, such as an uplink transmission power control command for an arbitrary terminal group. The base station determines the (E)PDCCH format according to the DCI transmitted to the terminal, 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 (E)PDCCH. (E) If the PDCCH is for a specific terminal, the cell-RNTI (C-RNTI) identifier of the terminal may be masked to the CRC. Alternatively, if the PDCCH is for a paging message, a paging indicator identifier (P-RNTI) may be masked on the CRC. If the PDCCH is for a system information block (SIB), a system information identifier and a system information RNTI (SI-RNTI) may be masked on the CRC. In order to indicate the random access response, which is a response to the transmission of the random access preamble of the terminal, a random access-RNTI (RA-RNTI) may be masked on the CRC.

5 is a diagram showing the structure of an uplink subframe. 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 to the data area. PUCCH for one terminal is allocated to a resource block pair (RB pair) in a subframe. Resource blocks belonging to a resource block pair occupy different subcarriers for 2 slots. This is called that the resource block pair allocated to the PUCCH is frequency-hopped at the slot boundary.

6 and 7 are diagrams for explaining resource mapping of CSI-RS.

6 shows RS resource mapping in a resource block pair in a normal CP case, and FIG. 7 shows an RS resource mapping in a resource block pair in an extended CP case. In the examples of FIGS. 6 and 7, in addition to the RE location to which the CSI-RS is mapped, the control region, CRS RE, and DM-RS RE locations are also shown. 6 and 7, in the case of two CRS antenna ports (i.e., antenna port numbers 0 and 1), the RE to which the CRS is mapped is shown, but is not limited thereto, and one CRS antenna port (ie, antenna Port number 0) or 4 CRS antenna ports (ie, antenna port numbers 0, 1, 2, 3) may also be applied to the examples of the present invention. In addition, although the control region in FIGS. 6 and 7 shows the use of the first 3 OFDM symbols, it is not limited thereto, and examples of the present invention are the same even when 1, 2, or 4 OFDM symbols are used. Can be applied. In addition, the DM-RS in FIGS. 6 and 7 shows the use of two CDM (Code Division Multiplexing) groups, but is not limited thereto, and examples of the present invention are the same even when one CDM group is used. Can be applied.

는 아래의 수학식 1에 따라 생성될 수 있다.Sequence for CSI-RS

May be generated according to Equation 1 below.

는 하향링크 최대 RB 개수를 나타낸다. In Equation 1, n _s denotes a slot number in a radio frame, and l denotes an OFDM symbol number in a corresponding slot.

Represents the maximum number of downlink RBs.

을 곱하는 정규화(normalization)를 수행함으로써 생성될 수 있다. 여기서, 의사 랜덤 시퀀스는 31-골드 시퀀스(Gold Sequence), c(i)를 이용하여 구성될 수 있다. c(i)는 2진(binary) 의사 랜덤 시퀀스이며, 0 또는 1의 값을 가진다. 따라서, 상기 수학식 1에서, 1-2·c(i)는 1 또는 -1 의 값을 가지고, 실수부에서는 짝수에 해당하는 2m 번째 시퀀스를 허수부에서는 홀수에 해당하는 2m+1 번째 시퀀스를 사용한다. 여기서, 의사 랜덤 시퀀스 c(i)는 아래의 수학식 2와 같이 초기화(initialize)된다.The CSI-RS sequence consists of a real part and an imaginary part respectively through a pseudo random sequence, and then each

It can be created by performing normalization multiplying by. Here, the pseudo-random sequence may be configured using a 31-gold sequence, c(i). c(i) is a binary pseudo-random sequence and has a value of 0 or 1. Therefore, in Equation 1, 1-2·c(i) has a value of 1 or -1, the 2m-th sequence corresponding to an even number in the real part and the 2m+1-th sequence corresponding to an odd number in the imaginary part use. Here, the pseudo-random sequence c(i) is initialized as shown in Equation 2 below.

는 0 내지 503 중의 하나의 정수 값을 가질 수 있으며, 상위 계층으로부터 시그널링되는 CSI-RS를 위한 가상 식별자에 해당한다. 만약 상위 계층으로부터

가 시그널링되지 않는 경우에는, 상기 수학식 2에서

의 값은 물리 셀 식별자(Physical Cell ID, PCI)인

와 동일한 값을 가진다.

는 노멀 CP를 사용하는 경우에는 1의 값을 가지고, 확장된 CP를 사용하는 경우에는 0의 값을 가진다.In Equation 2

May have an integer value of 0 to 503, and corresponds to a virtual identifier for CSI-RS signaled from an upper layer. If from the upper layer

When is not signaled, in Equation 2

Is the physical cell identifier (Physical Cell ID, PCI)

It has the same value as

Has a value of 1 when using a normal CP and a value of 0 when using an extended CP.

The generated CSI-RS sequence may be RE mapped and transmitted according to the following allocation scheme.

The CSI-RS may have one or more CSI-RS configurations per cell. The CSI-RS configuration may include a non-zero transmission power (NZP) CSI-RS configuration corresponding to the RE position at which the CSI-RS is transmitted to the UE of each cell (or radio radio head (RRH)). , Zero transmission power (ZP) CSI-RS configuration for muting a PDSCH region corresponding to CSI-RS transmission of an adjacent cell (or RRH) may be included.

In NZP CSI-RS configuration, one or more configurations may be signaled to each UE of a corresponding cell. Such signaling may be performed through higher layer (eg, RRC) signaling. The information signaled to the UE includes 2-bit information indicating whether the number of CSI-RS antenna ports is 1, 2, 4, or 8 (eg, antennaPortsCount parameter), and the basis for determining the RE location to which the CSI-RS is mapped. It may include 5-bit information (eg, resourceConfig parameter).

The 5-bit information, which is the basis for determining the RE location to which the CSI-RS is mapped, may indicate a CSI-RS pattern (ie, CSI-RS RE locations) configured for each number of CSI-RS antenna ports, and Table 1 below And it may be configured as shown in Table 2. Table 1 is applied to the case of normal CP, and Table 2 is applied to the case of extended CP.

In Table 1, when the number of antenna ports is 1 or 2, 32 CSI-RS patterns, when the number of antenna ports is 4, 16 CSI-RS patterns, and when the number of antenna ports is 8, 8 CSI-RS patterns. RS pattern is defined. 6 shows CSI-RS patterns according to the CSI-RS configuration number and the number of CSI-RS ports in Table 1.

In Table 2, 28 CSI-RS patterns when the number of antenna ports is 1 or 2, 14 CSI-RS patterns when the number of antenna ports is 4, and 7 CSI-RS patterns when the number of antenna ports is 8 RS pattern is defined. 7 shows CSI-RS patterns according to the CSI-RS configuration number and the number of CSI-RS ports in Table 2.

In Figures 6 and 7, the numbers (0, 1, 2, ..., 31) marked in each RE represent the CSI-RS setting number, and the alphabetic characters (a, b, c, d) are the CSI-RS antenna ports. Corresponds to the number. Specifically, a means that the corresponding RE is used for CSI-RS transmission through the CSI-RS antenna port number {15, 16}, and b indicates that the corresponding RE is the CSI-RS antenna port number {17, 18}. It means that it is used for CSI-RS transmission through, c means that the corresponding RE is used for CSI-RS transmission through the CSI-RS antenna port number {19, 20}, and d means that the corresponding RE is CSI- This means that it is used for CSI-RS transmission through RS antenna port numbers {21, 22}. CSI-RSs transmitted on two antenna ports using the same RE location may be multiplexed by a CDM method using an orthogonal cover code (OCC) to be distinguished from each other.

In addition, the ZP CSI-RS configuration may be configured with 16-bit bitmap information when the number of CSI-RS antenna ports is four. For example, in Table 1 or Table 2, each of the CSI-RS configurations when the number of CSI-RS antenna ports is 4 may correspond to one divided bit of a 16-bit bitmap. Each bit value (i.e., 0 or 1) of this bitmap is the case of transmitting the ZP CSI-RS by muting the PDSCH corresponding to the CSI-RS transmission of the adjacent cell or the transmission/reception point in the corresponding RE, and without muting The case of transmitting the PDSCH can be distinguished and signaled.

Based on (k', l') determined by the number of antenna ports and the CSI-RS configuration number in Table 1 or 2, and the value of n _s mod 2 0 or 1 (that is, the slot index is even or odd) Accordingly, the RE to which the CSI-RS is mapped may be determined according to Equation 3 below.

는 안테나 포트 인덱스 p, 부반송파 인덱스 k, OFDM 심볼 인덱스 l 에 매핑되는 복소 심볼(complex-valued symbol)을 의미하며, CSI-RS 시퀀스

에 직교 커버 코드(OCC)

가 곱해진 형태로 정의된다. In Equation 3

Denotes a complex-valued symbol mapped to an antenna port index p, a subcarrier index k, and an OFDM symbol index l, and a CSI-RS sequence

Orthogonal Cover Code (OCC)

Is defined as the multiplied form.

Tables 1 and 2 show 5-bit information on CSI-RS patterns that can be configured for each number of CSI-RS antenna ports in the normal CP and the extended CP, respectively. In Tables 1 and 2, k'and l'indicated by the number of antenna ports and the CSI-RS configuration number indicate a specific RE position of the CSI-RS pattern, and the remaining RE position(s) of the CSI-RS pattern are It can be calculated according to Equation 3 above. Accordingly, it is possible to determine the positions of all REs constituting the corresponding CSI-RS pattern.

For example, in the case of a normal CP, if the parameter for the number of CSI-RS antenna ports indicates 8 antenna ports, and the 5-bit information indicating the CSI-RS configuration number has a value of 00010 (ie, 2) Can be assumed. In this case, it can be seen that (k', l') = (9, 2) and n _s mod 2 = 1 in Table 1. That is, one of the RE positions to which the CSI-RS is mapped becomes a subcarrier index 9 on OFDM symbol index 2 in an odd-numbered index slot. Substituting this into Equation 3, it may be determined that 8 REs represented by 2a, 2b, 2c, and 2d of FIG. 6 are used for CSI-RS transmission.

파라미터 등을 포함할 수 있다. In addition, the higher layer (eg, RRC) signaling parameters related to CSI-RS are antennaPortsCount parameter, resourceConfig parameter, subframeConfig parameter, Pc parameter,

It may include parameters and the like.

The antennaPortsCount parameter is defined with a size of 2 bits, and may indicate the number of antenna ports used for CSI-RS transmission, corresponding to each column of Table 1 or Table 2.

The resourceConfig parameter is defined as a 5-bit size, and can indicate a resource used for CSI-RS transmission (i.e., RE of CSI-RS pattern) corresponding to each row of Table 1 or Table 2 have.

The subframeConfig parameter is defined as an 8-bit size, and may indicate a subframe used for CSI-RS transmission as shown in Table 3 below. The subframeConfig parameter may be defined as a combination of a CSI-RS transmission period T _CSI-RS and an offset Δ _CSI-RS .

The Pc parameter is a parameter indicating a value related to CSI-RS transmission power.

파라미터는 CoMP(Cooperative Multiple Point) 환경에서 물리 셀 식별자를 대체하는 값으로서 주어질 수 있다.

The parameter may be given as a value that replaces the physical cell identifier in CoMP (Cooperative Multiple Point) environment.

8 is a diagram illustrating a multi-antenna system according to an example of the present invention.

The multi-antenna system of FIG. 8 may include a base station (eNB) having a plurality of antennas and a terminal (UE) having a plurality of antennas. The example of FIG. 8 shows an example in which a base station has an antenna array in which 256 antenna elements are arranged in 16×16, and a terminal has an antenna array in which 16 antenna elements are arranged in 4×4. Here, the antenna element is a unit for classifying an antenna from the viewpoint of a physical antenna, and the antenna port from the viewpoint of a virtual antenna. The virtual antenna may be mapped one-to-one to the physical antenna, but when a plurality of physical antennas are grouped to transmit or receive the same signal, it may appear to operate as a single antenna, and such a plurality of physical antennas may be It can be expressed as forming a virtual antenna. As described above, since the mapping method between the physical antenna (or antenna element) and the virtual antenna (or antenna port) may be different depending on the implementation method, the operation of the communication system is mainly performed by the virtual transmission antenna (i.e., the transmission antenna port) and the virtual reception. It is common to define based on the antenna (ie, the receiving antenna port). Antenna virtualization can be said to adjust a channel (ie, an effective channel) between a virtual transmitting antenna and a virtual receiving antenna to be more advantageous for communication.

Unlike the prior art that supports only a one-dimensional antenna array supporting 1, 2, 4 or 8 antenna ports, the base station has 1, 2, 4, 8 antenna ports as well as more than 8 antenna ports as shown in FIG. A two-dimensional antenna array supporting antenna ports may be provided. More than eight antenna ports supported by the base station may correspond to, for example, 16, 32, 64, 128, 256, ... antenna ports. For example, 8 antenna ports in the prior art may be configured as an 8×1 1-dimensional antenna array, but 16 antenna ports may be configured as an 8×2 or 4×4 2-dimensional antenna array, or The 32 antenna ports may be configured as an 8×4 or 4×8 two-dimensional antenna array, or the 64 antenna ports may be configured as an 8×8 two-dimensional antenna array.

9 is a diagram illustrating an FD MIMO transmission scheme according to an example of the present invention.

A transmitter having a two-dimensional antenna array may perform FD MIMO transmission, for example, three-dimensional beamforming. That is, conventionally, in the beamforming of MIMO transmission, the direction of the beam can be adjusted in a specific azimuth direction, but the direction of the beam cannot be adjusted in the elevation direction (that is, the beam is formed in all directions at the elevation angle). Although only beamforming was possible, using an active antenna array (AAS) using a two-dimensional antenna array enables 3-dimensional beamforming that can adjust the direction of the beam in a specific azimuth direction and a specific elevation direction.

In the example of FIG. 9, a beam directed to a location of UE group #1 and a beam directed to a location of UE group #2 are separately shown. For example, even if UE group #1 and UE group #2 are located in the same direction in the azimuth direction, they may be located in different directions in the elevation direction, and different channels may be formed for each UE group. The CSI-RS may be transmitted so that the UE measures the state of each of these channels and feeds them back to the base station.

For FD-MIMO, it is required to support the number of CSI-RS antenna ports that are not supported in the prior art (eg, 3GPP LTE-A Release-12). For example, in the prior art, NZP CSI-RS resources having 1, 2, 4 or 8 antenna ports may be supported, and a CSI process having 1, 2, 4 or 8 antenna ports (here, one CSI process May support a plurality of NZP CSI-RS resources for a CSI-RS resource for channel measurement and a CSI-interference measurement resource (which may be associated with a CSI-IM resource). However, a method of supporting the number of new antenna ports per CSI-RS resource or per CSI process (eg, 6, 12, 16, 32, 64, ... CSI-RS antenna ports) has not been prepared yet. .

Hereinafter, examples of the present invention for a CSI-RS supporting a new number of antenna ports will be described. According to examples of the present invention, configuration (eg, resource allocation, etc.) related to CSI-RS transmission can be efficiently signaled according to the number of CSI-RS antenna ports variously required for FD-MIMO.

In various examples of the present invention, in addition to 1, 2, 4 or 8 CSI-RS antenna ports, a method of defining at least one of 6, 12, 16, 32, 64, ... CSI-RS antenna ports Include. For example, in addition to the configuration of the number of CSI-RS antenna ports of 1, 2, 4 or 8, a configuration of the number of CSI-RS antenna ports of more than 8 may be defined. For example, 12 CSI-RS antenna ports and a resource allocation method for the same are additionally defined, and 16 CSI-RS antenna ports and a resource allocation method for the same may be additionally defined.

10 is a diagram for explaining a CSI-RS-related operation for supporting FD-MIMO according to the present invention.

In step S1010, the base station (eNB) may transmit CSI-RS-related configuration information to the terminal (UE). The CSI-RS-related configuration information may include one or more of information on the number of CSI-RS antenna ports or CSI-RS resource allocation information. This is different from the information on the number of CSI-RS antenna ports and CSI-RS resource allocation information of the prior art, CSI-RS supporting a new antenna structure considering FD-MIMO (e.g., using more than 8 antenna ports CSI-RS) corresponding to the configuration information.

Information on the number of CSI-RS antenna ports is a new information in consideration of FD-MIMO by aggregating additional information to information indicating one of {1, 2, 4, 8} (eg, the aforementioned antennaPortsCount parameter). It may be configured in the form of indicating a new antenna port number candidate supporting antenna configuration. That is, by combining information indicating the number of CSI-RS antenna ports in one group, such as the antennaPortsCount parameter, and the additional information, the total number of CSI-RS antenna ports may be indicated. The additional information may have a size of 1 bit or 2 bits, and may be referred to as information indicating the number (eg, K) of CSI-RS antenna port groups. However, the additional information is not limited to the name, information indicating the number of CSI-RS resources, information indicating the number of CSI-RS configurations, information for determining the total number of CSI-RS antenna ports, This may mean indication information for classifying candidates for the number of CSI-RS antenna ports.

CSI-RS resource allocation information may be signaled for each of the CSI-RS antenna port groups. For example, CSI-RS resource allocation information may be individually or independently signaled as many as the number of CSI-RS antenna port groups (eg, Embodiment 1-1). Alternatively, CSI-RS resource allocation information is signaled only for one of the CSI-RS antenna port groups, and CSI-RS resources may be determined for the remaining CSI-RS antenna port group(s) according to a predetermined association rule (e.g. For example, Example 1-2).

In addition, information on the number of CSI-RS antenna ports and CSI-RS resource allocation information may be configured as individual signaling information (for example, Example 1 or Example 3), or as signaling information in the form of one bitmap. It may be configured (for example, Embodiment 2 or Embodiment 3).

In addition, the CSI-RS-related configuration information includes CSI-RS sequence generation parameters (eg, parameters defined in Equations 1 and 2), CSI-RS subframe configuration (eg, defined in Table 3 above). Parameters), or a CSI-RS transmission power parameter.

Such various CSI-RS-related configuration information may be provided through higher layer (eg, RRC) signaling, or may be included in system information and provided. In addition, various CSI-RS-related configuration information may be simultaneously provided through one signaling opportunity, or may be individually provided through different signaling opportunities.

In step S1015, the UE may determine a configuration of a CSI-RS antenna port, a resource location to which CSI-RS is mapped, a CSI-RS subframe location, and the like based on the CSI-RS-related configuration information received from the base station.

In step S1020, the base station may generate a CSI-RS sequence. The parameter related to CSI-RS sequence generation may use the same value as the parameter provided to the UE in step S1010, and the CSI-RS sequence may be generated by Equations 1 and 2.

In step S1030, the base station may map the generated CSI-RS sequence onto the REs. The RE location to which the CSI-RS is mapped may be determined by Equation 3 based on Table 1 and Table 2, etc., using the same values as the parameters provided to the UE in step S1010. In addition, the subframe to which the CSI-RS is mapped may be determined based on Table 3 or the like using the same value as the parameter provided to the terminal in step S1010.

In step S1040, the base station can transmit the CSI-RS mapped to the resource to the terminal, and the terminal receives the CSI-RS on the resource in which the CSI-RS is transmitted from the base station based on the CSI-RS-related configuration information determined in step S1015. can do.

In step S1050, the UE may estimate a downlink channel state from the received CSI-RS. As a result of channel state estimation, the UE may generate CSI (ie, calculate or determine a preferred RI, PMI, CQI, etc.).

In step S1060, the terminal may report the generated CSI to the base station. CSI reporting from the terminal to the base station may be periodically or aperiodically (or event-triggered).

Hereinafter, specific examples of the present invention for a signaling scheme for CSI-RS-related configuration information will be described.

Example 1

This embodiment relates to a CSI-RS antenna port number signaling scheme and a CSI-RS resource allocation signaling scheme.

First, a method for signaling the number of CSI-RS antenna ports will be described.

According to the present embodiment, 6, 12, 16, and 32 CSI-RS antenna ports may be additionally defined as candidates for the number of new CSI-RS antenna ports that can be transmitted in one and the same subframe. For example, the CSI-RS may be transmitted on 12 antenna ports, and in this case, the CSI-RS antenna port index may be 15, 16, 17, ..., 24, 25, 26. Alternatively, the CSI-RS may be transmitted on 16 antenna ports, and in this case, the CSI-RS antenna port index may be 15, 16, 17, ..., 28, 29, 30.

In order to indicate any one of the added CSI-RS antenna port number candidates, signaling information of an additional capacity may be defined and used. For example, in CSI-RS configuration, a size of a parameter indicating the number of antenna ports may be increased or aggregated with additional bits to indicate the number of CSI-RS antenna ports.

Signaling information indicating the number of CSI-RS antenna ports has a size of 2 bits, and indicates the number of 1, 2, 4, and 8 CSI-RS antenna ports, respectively, when the value of the 2-bit information is 00, 01, 10, 11 can do.

In order to signal the number of new CSI-RS antenna ports, information indicating the number of CSI-RS antenna ports having a size of 2 bits is redefined to new information of 3 bits or more, or information of 3 bits or more is configured by combining additional bits with the 2-bit information. And, the number of CSI-RS antenna ports may be indicated by using information of 3 bits or more. If information of 3 bits or more is used, the number of CSI-RS antenna ports of 6, 12, 16, or 32 can also be indicated.

For example, when new 3-bit information is defined, if the value is 000, 001, 010, 011, 100, 101, 110, 111, 1, 2, 4, 8, 6, 12, 16, 32 The number of CSI-RS antenna ports may be indicated.

As an additional example, in the case of defining 3-bit information by combining the 2-bit information with an additional 1-bit, when the additional bit value is 0, the 2-bit information value is 00, 01, 10, 11, respectively Indicate the number of 1, 2, 4, 8 CSI-RS antenna ports, and when the value of the additional bit is 1, 6, 12, 16, respectively, when the value of the 2-bit information is 00, 01, 10, 11 , It is possible to indicate the number of 32 CSI-RS antenna ports.

Here, in 3-bit information indicating the total number of antenna ports, the first bit position (i.e., an additional 1 bit) indicates the number of antenna port groups, and the remaining 2 bits indicate the number of antenna ports in one group. can do. For example, when the value of the first bit position is 0, it means that the number of antenna port groups (K) is 1, and when the value of the first bit position is 1, the number of antenna port groups (K) is It can also mean more than two. Specifically, when the total number of antenna ports is 1, 2, 4, 8 (that is, when the value of the first bit position in the 3-bit information values 000, 001, 010, 011 is 0), one antenna port group This can mean that it exists. When the total number of antenna ports is 6, 12, 16, 32 (that is, when the value of the first bit position is 1 in the 3-bit information values 100, 101, 110, 111), there are two or more antenna port groups. Can mean that. In addition, when the total number of antenna ports is 16 (that is, the value of 3 bits is 110), the value 1 of the first bit position indicates that there are two antenna port groups, and the value of the remaining bit positions 10 is It may mean that one antenna port group includes eight antenna ports (eg, a first group includes eight antenna ports and a second group includes eight antenna ports).

The 2-bit information is, for example, an antennaPortsCount parameter provided by RRC signaling, and the additional 1-bit information may be a parameter given by separate signaling, but the scope of the present invention is not limited thereto, and other 3 bits or more The number of CSI-RS antenna ports may be indicated through information or through aggregation of the 2-bit information and additional information.

Hereinafter, a CSI-RS resource allocation signaling scheme will be described.

As described above, when the number of CSI-RS antenna ports is indicated, CSI-RS resources used for CSI-RS transmission within one and the same subframe may be signaled as follows.

When the number of CSI-RS antenna ports is N (N=1, 2, 4, or 8), CSI-RS resource signaling information having a size of 5 bits may be used. The 5-bit information may indicate a CSI reference signal configuration corresponding to the number of N antenna ports in Table 1 or Table 2. Accordingly, from the values determined in Table 1 or 2, through Equation 3, 2 (when N=1 or 2), 4 (when N=4), and 8 (when N=8) RE location may be determined as a CSI-RS resource. Here, the CSI-RS resource signaling information may be a resourceConfig parameter provided through RRC signaling, but the scope of the present invention is not limited thereto.

When the number of CSI-RS antenna ports is M (M=6, 12, 16, 32) or when the number of CSI-RS antenna ports M is more than 8, the M CSI-RS antenna ports are the same number of antenna ports. It can be divided into K groups having

For example, when M=16 and K=2, some M/K (ie, 16/2=8) CSI-RS antenna ports belong to the first group, and the remaining M/K (ie, 16/ 2=8) CSI-RS antenna ports may belong to the second group. Here, a resource for 16 antenna port CSI-RS may correspond to a combination of two resources for 8 antenna port CSI-RS.

As another example, when M=32 and K=4, some M/4 (ie, 32/4=8) CSI-RS antenna ports belong to the first group, and some M/K (ie, 32/4=8) CSI-RS antenna ports belong to the second group, some M/K (ie, 32/4=8) CSI-RS antenna ports belong to the third group, and the rest M/K (ie, 32/4=8) CSI-RS antenna ports may belong to the fourth group. Here, the resource for the 32 antenna port CSI-RS may correspond to a combination of four resources for the 8 antenna port CSI-RS.

When the number of CSI-RS antenna ports is M (M=6, 12, 16, 32) or when the number of CSI-RS antenna ports M is more than 8, the M CSI-RS antenna ports have different numbers. It can be divided into K groups having antenna ports.

For example, when M=6 and K=2, some four CSI-RS antenna ports may belong to the first group, and the remaining two CSI-RS antenna ports may belong to the second group. Here, the resource for 6 antenna port CSI-RS may correspond to a combination of a resource for 4 antenna port CSI-RS and a resource for 2 antenna port CSI-RS.

As another example, when M=12 and K=2, some eight CSI-RS antenna ports may belong to the first group, and the remaining four CSI-RS antenna ports may belong to the second group. Here, the resource for 12 antenna port CSI-RS may correspond to a combination of a resource for 8 antenna port CSI-RS and a resource for 4 antenna port CSI-RS.

In the following description, it is assumed that information on CSI-RS resource allocation is based on the number of CSI-RS antenna ports, but is not limited thereto, and the CSI-RS antenna port number signaling method and the CSI-RS resource allocation signaling method are separately It can be applied in combination or applied in combination.

Example 1-1

According to this embodiment, in the case of a new CSI-RS antenna number candidate (eg, 6, 12, 16, 32, ...), a plurality of antenna ports are divided into a plurality of groups, and each of the groups is individually Alternatively, CSI-RS resources may be independently allocated. Accordingly, signaling overhead of resource allocation information may be proportional to the number of groups.

For example, the resource location to which the CSI-RS of the antenna port of the first group is mapped is signaled by the first resource allocation information, and the resource location to which the CSI-RS of the antenna port of the second group is mapped is the second resource allocation. It can be signaled by information. Even when the 3rd and 4th groups exist, the CSI-RS RE location may be signaled by different resource allocation information for each group. Here, as resource allocation information for each group, CSI-RS resource signaling information having a size of 5 bits each may be used. Here, the CSI-RS resource signaling information may be a resourceConfig parameter provided through RRC signaling, but the scope of the present invention is not limited thereto.

When M=6 and K=2, 4 in Table 1 or Table 2 according to the first resource allocation information (e.g., resourceConfig#1 parameter) for the first group to which some 4 CSI-RS antenna ports belong A CSI reference signal configuration corresponding to the number of antenna ports is indicated, and a CSI-RS resource consisting of 4 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal configuration corresponding to the number of two antenna ports in Table 1 or Table 2 according to the second resource allocation information (for example, resourceConfig#2 parameter) for the second group to which the remaining two CSI-RS antenna ports belong Is indicated, and a CSI-RS resource consisting of two REs may be determined according to Equation 3 from a value determined accordingly. In this case, in order to signal the resource allocation of the first and second groups, a total of 10 bits (i.e., 5 bits × K (here, the size of CSI-RS resource allocation information for one group is 5 bits, and the number of groups) K = 2) information is required.

When M=12 and K=2, 8 items in Table 1 or 2 according to the first resource allocation information (eg, resourceConfig#1 parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number of antenna ports is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal configuration corresponding to the number of four antenna ports in Table 1 or Table 2 according to the second resource allocation information (for example, resourceConfig#2 parameter) for the second group to which the remaining four CSI-RS antenna ports belong Is indicated, and a CSI-RS resource consisting of four REs may be determined according to Equation 3 from a value determined accordingly. In this case, in order to signal the resource allocation of the first and second groups, a total of 10 bits (i.e., 5 bits × K (here, the size of CSI-RS resource allocation information for one group is 5 bits, and the number of groups) K = 2) information is required.

In the case of M=16 and K=2, 8 items in Table 1 or 2 according to the first resource allocation information (eg, resourceConfig#1 parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number of antenna ports is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal configuration corresponding to the number of eight antenna ports in Table 1 or Table 2 according to the second resource allocation information (for example, resourceConfig#2 parameter) for the second group to which the remaining eight CSI-RS antenna ports belong Is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. In this case, in order to signal the resource allocation of the first and second groups, a total of 10 bits (i.e., 5 bits × K (here, the size of CSI-RS resource allocation information for one group is 5 bits, and the number of groups) K = 2) information is required.

When M=32 and K=4, 8 items in Table 1 or 2 according to the first resource allocation information (eg, resourceConfig#1 parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number of antenna ports is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal corresponding to the number of eight antenna ports in Table 1 or Table 2 according to the second resource allocation information (eg, resourceConfig#2 parameter) for the second group to which some other 8 CSI-RS antenna ports belong A configuration is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal corresponding to the number of eight antenna ports in Table 1 or Table 2 according to the third resource allocation information (for example, resourceConfig#3 parameter) for the third group to which some other 8 CSI-RS antenna ports belong A configuration is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. CSI reference signal corresponding to the number of eight antenna ports in Table 1 or Table 2 according to the fourth resource allocation information (eg, resourceConfig#2 parameter) for the fourth group to which the remaining 8 CSI-RS antenna ports belong A configuration is indicated, and a CSI-RS resource consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. In this case, a total of 20 bits (i.e., 5 bits×K) in order to signal resource allocation of the first, second, third, and fourth groups (here, the size of CSI-RS resource allocation information for one group is 5 It is a bit, and information of K=4), which is the number of groups, is required.

11 is a diagram for explaining a CSI-RS-related operation for supporting FD-MIMO according to an example of the present invention. Since steps S1110 to S1160 correspond to specific examples of steps S1010 to S1060 of FIG. 10, descriptions overlapping with the description of each step of FIG. 10 will be omitted from the description of each step of FIG. 11.

In step S1110, the base station (eNB) may transmit information indicating the number (M) of CSI-RS antenna ports, and K CSI-RS resource allocation information to the terminal (UE). Here, information indicating the number of CSI-RS antenna ports and CSI-RS resource allocation information may be simultaneously provided through one signaling opportunity, or may be provided individually through different signaling opportunities.

The total number of CSI-RS antenna ports may be expressed as M (M≥2). The K CSI-RS resource allocation information may be resource allocation information for CSI-RS resources composed of a combination of K (K≥2) groups. That is, the CSI-RS resource allocation information may include resource allocation information for each of the K CSI-RS resource groups. Since the M CSI-RS antenna ports may be divided into K antenna port groups corresponding to K CSI-RS resource groups, the number of CSI-RS resource groups may correspond to the number of CSI-RS antenna port groups.

In addition, the information indicating the total number of CSI-RS antenna ports M includes information indicating the number K of CSI-RS antenna port groups (or CSI-RS resource groups), and one CSI-RS antenna port group (or CSI -RS resource group) may be configured by combining information P indicating the number of antenna ports.

As a representative example, the number of antenna ports P=8 included in each CSI-RS antenna port group (or CSI-RS resource group), and the number of CSI-RS antenna port groups (or CSI-RS resource group) K=2 In the case of, the total number of antenna ports may be determined as M=16.

In this case, some of the eight antenna ports among M=16 CSI-RS antenna ports may correspond to the CSI-RS resources of the first group, and the remaining eight antenna ports may correspond to the CSI-RS resources of the second group. In this case, the CSI-RS resource allocation information is resource allocation information for CSI-RS resources of the first group and resource allocation information for CSI-RS resources of the second group, that is, K=2 CSI-RS resource allocation information. It may include.

That is, for a CSI-RS using more than 8 antenna ports, the CSI-RS resources of K (e.g., K=2) groups in one subframe are combined, so that the total number of KP antenna ports M (e.g. For example, M=16) can be obtained. The CSI-RS resources of each group in the combined CSI-RS resource may correspond to P (eg, P=2) antenna ports and one CSI-RS configuration of Table 1 or Table 2 above.

) 등이 추가적으로 단말에게 전송될 수 있다. In step S1110, CSI-RS subframe configuration information (eg, subframeConfig parameter), transmission power information (eg, Pc), CSI-RS sequence generation parameter (eg,

), etc. may be additionally transmitted to the terminal.

In step S1115, based on the CSI-RS-related configuration information received from the base station (especially, information on the total number of CSI-RS antenna ports, K CSI-RS resource allocation information), the UE is a resource location to which the CSI-RS is mapped, CSI- It is possible to determine a mapping relationship between an RS antenna port and a CSI-RS resource group, a CSI-RS subframe location, and the like.

In step S1120, the base station may generate a CSI-RS sequence.

In step S1130, the base station may map the CSI-RS sequence onto the CSI-RS resource. Specifically, a CSI-RS sequence may be mapped on a CSI-RS resource consisting of a combination of K groups signaled in step S1110 on a CSI-RS antenna port group corresponding to each CSI-RS resource group.

In step S1140, the base station may transmit a CSI-RS to the terminal. The UE may receive a CSI-RS based on the CSI-RS-related configuration information determined in step S1115.

In step S1150, the UE may estimate a channel based on CSI-RS.

In step S1160, the UE may generate or calculate CSI based on the channel estimation and report it to the base station.

Example 1-2

According to the present embodiment, in the case of a new CSI-RS antenna number candidate (eg, 6, 12, 16, 32, ...), a plurality of antenna ports are divided into a plurality of groups, and any one of the plurality of groups Only CSI-RS resource allocation information for a group of is signaled, and CSI-RS resource allocation for the remaining group(s) may be automatically determined according to a predetermined association rule. That is, it may be expressed that resource allocation for one group among a plurality of groups is explicitly signaled, and resource allocation for the other group(s) is implicitly signaled. Accordingly, the signaling overhead of resource allocation information can be kept constant regardless of the number of groups.

When M=6 and K=2, four antenna ports in Table 1 or Table 2 according to the first resource allocation information (eg, resourceConfig parameter) for the first group to which some of the four CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number is indicated, and a CSI-RS resource consisting of 4 REs may be determined according to Equation 3 from a value determined accordingly. CSI-RS resources allocated for the second group to which the remaining two CSI-RS antenna ports belong are CSI-RS resources allocated for the first group and Tables 4, 5, 6, 7, 8 or 9 below. It can be automatically determined according to the related rules of In this case, a total of 5 bits of information are required to signal resource allocation of the first and second groups.

The association rules of Tables 4, 5, 6, 7, 8, or 9 below are exemplary, and the scope of the present invention is not limited thereto.

Table 4 shows an example of an association rule in the case of a normal CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 1 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -6 from the two REs determined in Table 1 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 4. According to the example of Table 4, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 4, 20, 21, 22, 2 of the subcarrier position determined by k'in Table 1 If the CSI-RS configuration index for the first group is 5, 6, 7, 8, 9, 23, 24, 25 at the position shifted by -1 from the RE to the frequency axis, according to k'in Table 1 CSI-RS resources for the second group are allocated at a position shifted by +1 to the frequency axis in two REs of the determined subcarrier positions.

Table 5 shows another example of the association rule in the case of normal CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 1 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -6 from the two REs determined in Table 1 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 5. According to the example of Table 5, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 4, 20, 21, 22, 2 of the subcarrier position determined by k'in Table 1 If the CSI-RS configuration index for the first group is 5, 6, 7, 8, 9, 23, 24, 25 at the position shifted by -7 from the RE to the frequency axis, according to k'in Table 1 CSI-RS resources for the second group are allocated at positions shifted by -5 on the frequency axis in two REs of the determined subcarrier positions.

Table 6 shows another example of an association rule in the case of a normal CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 1 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -6 from the two REs determined in Table 1 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 6. According to the example of Table 6, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 4, 20, 21, 22, 2 of the subcarrier position determined by k'in Table 1 If the CSI-RS configuration index for the first group is 5, 6, 7, 8, 9, 23, 24, 25 at the position shifted by -1 from the RE to the frequency axis, according to k'in Table 1 CSI-RS resources for the second group are allocated at positions shifted by -5 on the frequency axis in two REs of the determined subcarrier positions.

Table 7 shows an example of an association rule in the case of an extended CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 2 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -3 from the two REs determined by Table 2 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 7. According to the example of Table 7, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 16, 17, 18, two REs at the subcarrier positions determined by k'in Table 2 In the case where the CSI-RS configuration index for the first group is 4, 5, 6, 7, 19, 20, 21 at the position shifted by -6 to the frequency axis, the subcarrier position determined by k'in Table 2 CSI-RS resources for the second group are allocated at a position shifted by +6 to the frequency axis in two REs of.

Table 8 shows another example of an association rule in the case of an extended CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 2 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -3 from the two REs determined by Table 2 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 8. According to the example of Table 8, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 16, 17, 18, two REs at the subcarrier positions determined by k'in Table 2 In the case where the CSI-RS configuration index for the first group is 4, 5, 6, 7, 19, 20, 21 at the position shifted by -9 to the frequency axis, the subcarrier position determined by k'in Table 2 CSI-RS resources for the second group are allocated at a position shifted by +3 to the frequency axis in two REs of.

Table 9 shows another example of the association rule in the case of the extended CP. CSI-RS transmitted on the first two antenna port indexes {15, 16} among the 6 CSI-RS antenna port indexes {15, 16, 17, 18, 19, 20} are subcarriers determined by k'in Table 2 CSI-RS transmitted on the next two antenna port indexes {17, 18} at a position shifted by -0 from the two REs of the position to the frequency axis is -3 from the two REs determined by Table 2 These are the CSI-RS resource allocation positions that are signaled directly by the resourceConfig parameter.

In this way, based on the resource location determined for the first group (eg, four antenna ports {15, 16, 17, 18}), the second group (eg, the remaining two antenna ports {19, 20) The resource location for }) may be determined according to the association rule of Table 8. According to the example of Table 8, when the CSI-RS configuration index for the first group is 0, 1, 2, 3, 16, 17, 18, two REs at the subcarrier positions determined by k'in Table 2 In the case where the CSI-RS configuration index for the first group is 4, 5, 6, 7, 19, 20, 21 at the position shifted by -6 to the frequency axis, the subcarrier position determined by k'in Table 2 CSI-RS resources for the second group are allocated at a position shifted by +3 to the frequency axis in two REs of.

When M=12 and K=2, 8 antenna ports in Table 1 or 2 according to the first resource allocation information (eg, resourceConfig parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number is indicated, and CSI-RS resources consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. The CSI-RS resources allocated for the second group to which the remaining four CSI-RS antenna ports belong are based on the CSI-RS resources allocated for the first group and the association rules of Tables 10, 11, 12 or 13 below. It can be automatically determined according to. In this case, a total of 5 bits of information are required to signal resource allocation of the first and second groups.

The association rules in Tables 10, 11, 12, or 13 below are exemplary, and the scope of the present invention is not limited thereto. Tables 10 and 11 show the association rules for resource allocation of the first group and the second group in the case of a normal CP, and Tables 12 and 13 are the resource allocation of the first group and the second group in the case of an extended CP. Represents an association rule. The association rules shown in each table are not the same as the examples of Tables 4 to 9, but are similar, and thus can be understood with reference to the description of Tables 4 to 9.

When M=16 and K=2, 8 antenna ports in Table 1 or 2 according to the first resource allocation information (eg, resourceConfig parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number is indicated, and CSI-RS resources consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. The CSI-RS resources allocated for the second group to which the remaining 8 CSI-RS antenna ports belong are to the CSI-RS resources allocated for the first group and the association rules of Tables 14, 15, 16 or 17 below. It can be automatically determined according to. In this case, a total of 5 bits of information are required to signal resource allocation of the first and second groups.

The association rules in Tables 14, 15, 16, or 17 below are exemplary, and the scope of the present invention is not limited thereto. Tables 14 and 15 show the association rules for resource allocation of the first group and the second group in the case of a normal CP, and Tables 16 and 17 show the resource allocation of the first group and the second group in the case of an extended CP. Represents an association rule. The association rules shown in each table are not the same as the examples of Tables 4 to 9, but are similar, and thus can be understood with reference to the description of Tables 4 to 9.

When M=32 and K=4, 8 antenna ports in Table 1 or 2 according to the first resource allocation information (for example, resourceConfig parameter) for the first group to which some 8 CSI-RS antenna ports belong CSI reference signal configuration corresponding to the number is indicated, and CSI-RS resources consisting of 8 REs may be determined according to Equation 3 from a value determined accordingly. The CSI-RS resources allocated to the second group, the third group, and the fourth group to which the remaining 24 CSI-RS antenna ports belong are CSI-RS resources allocated to the first group and Tables 18 and 19 below. , It may be automatically determined according to the association rule of 20 or 21. In this case, a total of 5 bits of information are required to signal resource allocation of the first, second, third, and fourth groups.

The association rules in Tables 18, 19, 20, or 21 below are exemplary, and the scope of the present invention is not limited thereto. Tables 18 and 19 show the association rules for resource allocation of the first, second, third and fourth groups in the case of a normal CP, and Tables 20 and 21 are the first, second, and Represents an association rule for resource allocation in the third and fourth groups. The association rules shown in each table are not the same as the examples of Tables 4 to 9, but are similar, and thus can be understood with reference to the description of Tables 4 to 9.

Example 2

This embodiment relates to a method of defining and using a new field indicating CSI-RS antenna port number information and CSI-RS resource allocation information simultaneously. For example, CSI-RS antenna port number information uses the antennaPortsCount parameter, and CSI-RS resource allocation information uses a resourceConfig parameter instead of using a new field (e.g., FD-MIMO CSI-RS Integrated setting information) can be defined.

Example 2-1

In this embodiment, a new field may be defined as a 32-bit bitmap. For example, although it is similar to a bitmap indicating ZP CSI-RS configuration, the 32-bit bitmap of the present embodiment may be referred to as joint-encoded information about the number of CSI-RS antenna ports and CSI-RS resource allocation information. Each bit position of the 32-bit bitmap may correspond to a CSI reference signal configuration value for the number of one or two CSI-RS antenna ports in Table 1 or Table 2. For example,

In this case, when the number of CSI-RS antenna ports is 1 or 2, one bit position among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 4, any two bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 8, any four bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 6, any three bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 12, six bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 16, any 8 bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 32, any 16 bit positions among 32 bits may have a value of "1" and the rest may have a value of "0".

Additionally, additional 1-bit information may be required to distinguish the case where the number of CSI-RS antenna ports is odd and even. In this case, when the value of the additional 1-bit information is the first value, it indicates that the number of CSI-RS antenna ports is an odd number, and the bit value corresponding to the last bit among bits having a bit value of 1 in a 32-bit bitmap In two REs, a CSI-RS may be transmitted on one antenna port. Alternatively, when the value of the additional 1-bit information is the second value, it may indicate that the number of CSI-RS antenna ports is an even number. Here, the first value and the second value may be 1 and 0, respectively, or may be 0 and 1, respectively.

Example 2-2

In this embodiment, a new field may be defined as a 16-bit bitmap. For example, although it is similar to a bitmap indicating ZP CSI-RS configuration, the 16-bit bitmap of the present embodiment may be referred to as joint-encoded information about the number of CSI-RS antenna ports and CSI-RS resource allocation information. Each bit position of the 16-bit bitmap may correspond to a CSI reference signal configuration value for the number of four CSI-RS antenna ports in Table 1 or Table 2.

In this case, when the number of CSI-RS antenna ports is 1 or 2, one of the 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 4, one bit position among 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 8, any two bit positions among 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 6, any two bit positions among 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 12, three bit positions among 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 16, any 4 bit positions among 16 bits may have a value of "1" and the rest may have a value of "0".

When the number of CSI-RS antenna ports is 32, any eight bit positions among 16 bits may have a value of "1" and the rest may have a value of "0".

As described above, in signaling using a 16-bit bitmap, it is necessary to distinguish the case where the number of CSI-RS antenna ports is 1, 2, or 4, and the number of CSI-RS antenna ports is 6 or 8 Individual cases need to be distinguished from each other. For this, additional 2-bit information may be required.

When the number of CSI-RS antenna ports is P, when the value of additional 2-bit information is 00, the number of CSI-RS antenna ports satisfying P mod 4 = 0 (e.g., P = 4, 8, 12, 16, ..., 32, ...) can be indicated.

If the value of the additional 2-bit information is 01, the number of CSI-RS antenna ports satisfying P mod 4 = 1 (eg, P=1) may be indicated. In this case, one antenna from only two REs of the high frequency side (or the low frequency side) on the frequency axis among the 4 REs corresponding to the last bit among the bits with a bit value of 1 in the 16-bit size bitmap. CSI-RS may be transmitted on the port.

When the value of the additional 2-bit information is 10, the number of CSI-RS antenna ports satisfying P mod 4 = 2 (eg, P=2, 6) may be indicated. In this case, of the 4 REs corresponding to the last bit among the bits with a bit value of 1 among the 16-bit bitmap, only 2 antennas on the 2 REs of the high frequency side (or the low frequency side) on the frequency axis CSI-RS may be transmitted on the port.

When the value of the additional 2-bit information is 11, the number of CSI-RS antenna ports satisfying P mod 4 = 3 may be indicated. In this case, one antenna from two REs of the high frequency side (or the low frequency side) on the frequency axis among 4 REs corresponding to the last bit among the bits with a bit value of 1 among the 16-bit bitmap CSI-RS may be transmitted on the port, and CSI-RS may be transmitted on two antenna ports in the remaining two REs among the four REs.

Here, since the number of CSI-RS ports satisfying P mod 4 = 3 may not exist, the value 11 of the additional 2-bit information may be reserved.

In addition, P mod 4 = Q (here, Q = 0, 1, 2 or 0, 1, 2, 3) for the number of P CSI-RS antenna ports satisfying 3 cases or 4 cases and the additional 2 The correspondence relationship of bit information is not limited to the above examples, and the scope of the present invention may include other correspondence relationships.

Meanwhile, as the additional 2-bit information, the antennaPortsCount parameter may be reused. For example, if the value of the antennaPortsCount parameter is 00, it indicates one CSI-RS antenna port, if it is 01, it indicates two CSI-RS antenna ports, and if it is 10, it indicates 4 or 6 CSI-RS An antenna port may be indicated, and in the case of 11, it may be defined as indicating 8, 12, 16 or 32 CSI-RS antenna ports.

Here, when indicating that the value of the 2-bit information is 00 and the number of CSI-RS antenna ports is 1, the frequency among 4 REs corresponding to one bit having a value of "1" in a 16-bit bitmap CSI-RS can be transmitted on one antenna port only on two REs on the high frequency side (or the low frequency side) on the axis.

When indicating that the value of the 2-bit information is 01 and the number of CSI-RS antenna ports is 2, among 4 REs corresponding to one bit having a value of "1" in a 16-bit bitmap, on the frequency axis CSI-RS can be transmitted on two antenna ports only in two REs on the high frequency side (or on the low frequency side).

When indicating that the value of the 2-bit information is 10 and the number of CSI-RS antenna ports is 4, 4 antennas in 4 REs corresponding to one bit having a value of "1" in a 16-bit bitmap CSI-RS may be transmitted on the port.

When indicating that the value of the 2-bit information is 10 and the number of CSI-RS antenna ports is 6, 4 REs corresponding to the first bit among 2 bits having a value of "1" in a 16-bit bitmap CSI-RS is transmitted on 4 antenna ports, and CSI-RS on 2 antenna ports only on 2 REs on the high frequency side (or on the low frequency side) on the frequency axis among 4 REs corresponding to the other bit Can be transmitted.

When indicating that the value of the 2-bit information is 11 and the number of CSI-RS antenna ports is 8, 8 antennas in 8 REs corresponding to 2 bits having a value of "1" in a 16-bit bitmap CSI-RS may be transmitted on the port.

When indicating that the value of the 2-bit information is 11 and the number of CSI-RS antenna ports is 12, 12 antennas in 12 REs corresponding to 3 bits having a value of "1" in a 16-bit bitmap CSI-RS may be transmitted on the port.

When indicating that the value of the 2-bit information is 11 and the number of CSI-RS antenna ports is 16, 16 antennas in 16 REs corresponding to 4 bits having a value of "1" in a 16-bit bitmap CSI-RS may be transmitted on the port.

When indicating that the value of the 2-bit information is 11 and the number of CSI-RS antenna ports is 32, 32 antennas in 32 REs corresponding to 8 bits having a value of "1" in a 16-bit bitmap CSI-RS may be transmitted on the port.

In the above-described embodiments 1-1, 1-2, 2-1, and 2-2, the configuration of the number of CSI-RS antenna ports and the flexibility of allocating CSI-RS resources is the highest in the embodiment 2-1. Example 2-2, 1-1, and 1-2 in order. On the other hand, the setting of the number of CSI-RS antenna ports and the signaling overhead of CSI-RS resource allocation is the lowest in Embodiment 1-2, and increases in the order of Embodiments 1-1, 2-2, and 2-1.

Example 3

This embodiment relates to a method of supporting more than 32 CSI-RS antenna ports.

In the case of 32 or less CSI-RS antenna ports, different antenna ports are divided by different codes (e.g., OCC) within one subframe, and different antenna ports are divided into CDM (Code Division Multiplexing). Using one or more multiplexing schemes of FDM (Frequency Division Multiplexing) classified by different subcarrier positions or TDM (Time Division Multiplexing) where different antenna ports are divided by different OFDM symbol positions, up to 32 CSI- CSI-RS can be simultaneously transmitted from the RS antenna port. However, when CSI-RS is transmitted on more than 32 antenna ports within one subframe, the overhead of CSI-RS transmission is high, and thus CSI-RS can be transmitted using more than one subframe.

For example, when there are 64 CSI-RS antenna ports, two subframes may be used for CSI-RS transmission. That is, CSI-RS may be transmitted on some 32 antenna ports among 64 antenna ports in the first subframe, and CSI-RS may be transmitted on the remaining 32 antenna ports in the second subframe.

Here, the first subframe may be determined based on the aforementioned subframeConfig parameter, or the like, and the second subframe may be determined as the first available subframe after the first subframe. For example, the second subframe may be a next subframe contiguous to the first subframe, and if CSI-RS transmission is not possible in the next subframe contiguous to the first subframe, the second subframe is next It may be an available subframe.

In addition, resource configuration for CSI-RS transmission on 32 antenna ports in the first subframe and resource configuration for CSI-RS transmission on 32 antenna ports in the second subframe may be the same. Accordingly, only signaling for CSI-RS configuration for the first subframe is required, and signaling for separate CSI-RS configuration for the second subframe may not be required.

In addition, in order to signal the number of antenna ports greater than 32, one candidate number of antenna ports greater than 32 is added to the set of CSI-RS antenna port number candidates excluding any one element from {6, 12, 16, 32}. It can also be configured in a way that For example, the set of CSI-RS antenna port number candidates is {12, 16, 32, 64}, {6, 16, 32, 64}, {6, 12, 32, 64}, or {6, 12, 16, 64}. In this case, in the CSI-RS antenna port number signaling scheme and the CSI-RS resource allocation signaling scheme described in the above-described embodiments 1 and 2, an embodiment for a specific one antenna port number candidate is implemented for an antenna port number candidate greater than 32 Can be replaced by example. Accordingly, no additional signaling overhead occurs compared to the above-described Embodiments 1 and 2.

Alternatively, in order to signal the number of antenna ports greater than 32, one candidate for the number of antenna ports greater than 32 may be added to the set {6, 12, 16, 32} of the CSI-RS antenna port number candidates. For example, the set of CSI-RS antenna port number candidates may be composed of {6, 12, 16, 32, 64}. In this case, additional 1-bit signaling to distinguish between 32 antenna ports and 64 antenna ports in the CSI-RS antenna port number signaling scheme and the CSI-RS resource allocation signaling scheme described in Embodiments 1 and 2 described above. You may need this.

Although the above-described exemplary methods are represented as a series of operations for simplicity of description, this is not intended to limit the order in which the steps are performed, and each step may be performed simultaneously or in a different order if necessary. In addition, not all illustrated steps are necessary to implement the method according to the invention.

The above-described embodiments include examples of various aspects of the present invention. Although not all possible combinations for representing the various aspects can be described, those of ordinary skill in the art will recognize that other combinations are possible. Accordingly, the present invention will be said to include all other replacements, modifications and changes falling within the scope of the following claims.

The scope of the present invention includes an apparatus (eg, a wireless device described with reference to FIG. 1 and components thereof) that processes or implements an operation according to various embodiments of the present disclosure.

12 is a diagram illustrating a configuration of a processor according to the present invention.

A new antenna configuration in consideration of FD-MIMO described in various examples of the present invention by the upper layer processing unit 111 and the physical layer processing unit 112 of the processor 110 of the terminal 100 (e.g., more than 8 An operation of receiving and processing a CSI-RS supporting (antenna port of) may be performed.

The upper layer processing unit 111 may include a CSI-RS related setting information determining unit 1110. CSI-RS-related configuration information determiner 1110 is CSI-RS-related configuration information (e.g., CSI-RS antenna port number information, CSI-RS resource allocation information) provided from the base station 200 through higher layer signaling, etc. , CSI-RS sequence generation parameter, CSI-RS subframe allocation information, CSI-RS transmission power information, etc.), and the terminal 100 may control to correctly receive the CSI-RS based on the corresponding information.

Here, the CSI-RS-related configuration information corresponds to configuration information for a CSI-RS (eg, CSI-RS using more than 8 antenna ports) supporting a new antenna structure in consideration of FD-MIMO. The CSI-RS-related configuration information determination unit 1110 includes information on the number of CSI-RS antenna ports, such as the antennaPortsCount parameter, information indicating the number of CSI-RS antenna ports in one group, and additional information (for example, For example, by combining the number of CSI-RS antenna port groups or the number of CSI-RS resources), the total number of CSI-RS antenna ports may be determined. Also, the CSI-RS-related configuration information determiner 1110 may determine CSI-RS resource allocation information for each of the CSI-RS antenna port groups. For example, using CSI-RS resource allocation information signaled as much as the number of CSI-RS antenna port groups, or resources for the remaining group(s) based on CSI-RS resource allocation information signaled for one group. You can decide. Here, the CSI-RS-related configuration information determination unit 1110 may process information on the number of CSI-RS antenna ports and CSI-RS resource allocation information as individual signaling information, or as signaling information in the form of one bitmap. You can also handle it.

The physical layer processing unit 112 may include a CSI-RS reception processing unit 1121 and a CSI report transmission unit 1123. The CSI-RS reception processing unit 1121 may receive a CSI-RS based on CSI-RS-related configuration information provided through higher layer signaling or the like. The CSI report transmitter 1123 may generate CSI based on the estimated channel information using the received CSI-RS and transmit it to the base station 200.

A new antenna configuration in consideration of FD-MIMO described in various examples of the present invention by the upper layer processing unit 111 and the physical layer processing unit 112 of the processor 210 of the base station 200 (for example, more than 8 An operation of generating and transmitting a CSI-RS supporting (antenna port of) may be performed.

The upper layer processing unit 211 may include a CSI-RS related setting information determining unit 2110. CSI-RS-related configuration information determination unit 2110 is CSI-RS-related configuration information to be transmitted to the terminal 100 (eg, CSI-RS antenna port number information, CSI-RS resource allocation information, CSI-RS sequence generation parameter , CSI-RS subframe allocation information, CSI-RS transmission power information, etc.) can be determined and transmitted to the terminal 100 through the physical layer processing unit 212.

Here, the CSI-RS-related configuration information corresponds to configuration information for a CSI-RS (eg, CSI-RS using more than 8 antenna ports) supporting a new antenna structure in consideration of FD-MIMO. The CSI-RS-related configuration information determination unit 2110 includes information on the number of CSI-RS antenna ports, such as the antennaPortsCount parameter, information indicating the number of CSI-RS antenna ports in one group, and additional information (e.g. For example, by providing the number of CSI-RS antenna port groups or the number of CSI-RS resources), the total number of CSI-RS antenna ports may be signaled to the terminal 100. In addition, the CSI-RS related configuration information determiner 2110 may determine and signal CSI-RS resource allocation information for each of the CSI-RS antenna port groups. For example, signaling CSI-RS resource allocation information as much as the number of CSI-RS antenna port groups, or signaling CSI-RS resource allocation information for only one group, and a predetermined association rule for the remaining group(s) According to the terminal 100 may be determined. Here, the CSI-RS-related configuration information determination unit 2110 may process information on the number of CSI-RS antenna ports and CSI-RS resource allocation information as individual signaling information, or as signaling information in the form of one bitmap. You can also handle it.

The physical layer processing unit 212 may include a CSI-RS sequence generation unit 2121 and a CSI-RS resource mapping unit 2123. The CSI-RS sequence generator 2121 may generate a CSI-RS sequence based on a CSI-RS sequence generation parameter determined in an upper layer. The CSI-RS resource mapping unit 2123 maps the generated CSI-RS sequence onto the RE determined according to CSI-RS resource allocation information and subframe allocation information, and the resource-mapped CSI-RS to the terminal 100. Can be transmitted.

The above-described operation of the processor 110 of the terminal 100 or the processor 210 of the base station 200 may be implemented by software processing or hardware processing, or by software and hardware processing. The scope of the present invention is a software (or operating system, application, firmware, program, etc.) that allows an operation according to various embodiments of the present invention to be executed on a device or computer, and storing and executing such software on a device or computer. Includes possible medium.

Although various embodiments of the present invention have been described centering on a 3GPP LTE or LTE-A system, they can be applied to various mobile communication systems.

Claims (8)

In a method for transmitting a channel state information reference signal (CSI-RS) of a base station,
Generating signaling information including information on the number of CSI-RS antenna ports and information indicating the location of CSI-RS resources,
Transmitting the signaling information to a terminal,
Generating a reference sequence for the CSI-RS, including a pseudo-random sequence,
Mapping the reference sequence to the plurality of CSI-RS resources, and
Transmitting the CSI-RS including the mapped reference sequence to the terminal through the plurality of CSI-RS resources,
The number of CSI-RS antenna ports is a maximum of 32, and the information indicating the CSI-RS resource location indicates frequency domain allocation information in a resource block.
CSI-RS transmission method. The method of claim 1, wherein the information on the number of CSI-RS antenna ports and information indicating the CSI-RS resource location are joint encoded. The method of claim 1, wherein the signaling information includes code division multiplexing (CDM) scheme information. The method of claim 3, wherein the CDM multiplexes the CSI-RS using an orthogonal cover code. In the method for reporting channel state information of a terminal,
Receiving signaling information including channel state information reference signal (CSI-RS) antenna port number information and information indicating a CSI-RS resource location from a base station,
Receiving a CSI-RS from the base station through a plurality of CSI-RS resources,
Generating channel state information using the CSI-RS received from the plurality of CSI-RS resources, and
Reporting the channel state information to the base station,
The CSI-RS antenna port number information is a maximum of 32 CSI-RS antenna ports, and the CSI-RS resource location information indicates frequency domain allocation information in a resource block.
How to report channel status information. 6. The method of claim 5, wherein the information on the number of CSI-RS antenna ports and information indicating the CSI-RS resource location are joint encoded. The method of claim 5, wherein the signaling information includes code division multiplexing (CDM) scheme information. The method of claim 7, wherein the CDM multiplexes the CSI-RS using an orthogonal cover code.

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