KR20200024814A - Apparatus and method for transmitting/receiving downlink data in a radio communication system using a cooperative multi-point transmission - Google Patents

Abstract

Disclosed are a downlink data transmitting and receiving apparatus and method in a wireless communication system supporting cooperation between transmission points. According to the present invention, a downlink data transmission method in a wireless communication system comprises: transmitting information of a resource management set including information of a channel state information reference signal (CSI-RS) for measuring received power of a terminal, to the terminal; receiving a received power measurement report of the CSI-RS corresponding to the resource management set, from the terminal; determining a measurement set including the information of the CSI-RS for the terminal to perform channel estimation based on the received power measurement report; and transmitting resources to which data are mapped based on the measurement set, to the terminal.

Description

Apparatus and method for downlink data transmission and reception in a wireless communication system supporting cooperative transmission point {APPARATUS AND METHOD FOR TRANSMITTING / RECEIVING DOWNLINK DATA IN A RADIO COMMUNICATION SYSTEM USING A COOPERATIVE MULTI-POINT TRANSMISSION}

The present invention relates to an apparatus and method for transmitting and receiving downlink data in a wireless communication system using a cooperative multi-point (CoMP) scheme.

The wireless communication system has evolved into a high-speed, high-quality wireless packet data communication system for providing data and multimedia services beyond the initial voice-oriented services. Recent 3GPP high speed downlink packet access (HSDPA), high speed uplink packet access (HSUPA), long term evolution (LTE), long term evolution advanced (LTE-A), high rate packet data (HRPD) of 3GPP2, and IEEE Various wireless communication standards such as 802.16 were developed to support high speed, high quality wireless packet data transmission services.

The LTE system is developed to efficiently support high-speed wireless packet data transmission. The LTE system can maximize radio system capacity by utilizing various radio access technologies. The LTE-A system is an advanced wireless system of the LTE system and has improved data transmission capability compared to LTE.

Existing third generation wireless packet data communication systems such as HSDPA, HSUPA, and HRPD use techniques such as adaptive modulation and coding (AMC) and channel sensitive scheduling to improve transmission efficiency. In this case, the AMC method and the channel sensitive scheduling method may apply appropriate modulation and coding schemes at the time when it is determined to be the most efficient by receiving partial channel state information from the receiver.

In the wireless packet data communication system to which the AMC method is applied, the transmitter may adjust the amount of data to be transmitted according to channel conditions. In other words, if the channel condition is bad, the transmitter can reduce the amount of data to be transmitted to match the reception error probability to a desired level. If the channel condition is good, the transmitter can increase the amount of data to be transmitted so that the reception error probability can be effectively transmitted while keeping the reception error probability to a desired level.

In a wireless packet data communication system using a channel sensitive scheduling resource management method, a transmitter selectively services a user having a good channel condition among several users, thereby increasing system capacity compared to allocating and serving a channel to one user. This increase in capacity is called the multi-user diversity gain. The AMC method may also include a function of determining the number or rank of spatial layers of a signal to be transmitted when used with a multiple input multiple output (MIMO) transmission scheme. In this case, the wireless packet data communication system to which the AMC method is applied determines not only the code rate and the modulation scheme but also how many layers are transmitted using MIMO to determine the optimal data rate.

In general, it is known that capacity can be expected to be increased in the OFDMA method as compared to the CDMA method. One of various causes of capacity increase in the OFDMA scheme is that frequency domain scheduling can be performed. Just as the channel gains capacity gains through channel-sensitive scheduling as the channel changes over time, more capacity gains can be achieved if the channel utilizes different characteristics depending on frequency. In recent years, researches are actively being conducted to convert code division multiple access (CDMA), which is used in second and third generation wireless communication systems, to orthogonal frequency division multiple access (OFDMA) in a next generation system. And 3GPP and 3GPP2 have begun standardizing on evolutionary systems using OFDMA.

Meanwhile, in the LTE-A system, a CoMP transmission technology has been proposed in which a plurality of cells perform cooperative transmission to a terminal. When the CoMP transmission technique is applied, the terminal may be allocated a plurality of CSI-RSs in a resource block transmitted from the base station to the terminal for efficient channel estimation from the plurality of cells. Considered CoMP data transmission and reception method is needed.

In order to efficiently use the CoMP scheme in an LTE-A system, downlink data is considered in consideration of channel state information reference signal (CSI-RS) resources transmitted in cells corresponding to a plurality of transmission points. There is a need for a method of receiving a physical downlink shared channel (PDSCH) signal.

However, in the current LTE-A system, it is assumed that downlink data is not mapped to all CSI-RS resources allocated by the UE, and thus, PDSCH signals are assumed to be received. Therefore, unnecessary resource waste occurs when multiple CSI-RS resources are allocated. Can be.

An object of the present invention is to provide an apparatus and method for transmitting and receiving downlink data by efficiently utilizing resources when a plurality of CSI-RSs are allocated to a terminal for channel estimation.

In order to achieve the above technical problem, the method for transmitting downlink data in a wireless communication system according to the present invention includes transmitting information of a resource management set including information of a CSI-RS for measuring a reception power of a terminal to the terminal. step; Receiving a reception power measurement report of a CSI-RS corresponding to the resource management set from the terminal; Determining a measurement set including information of a CSI-RS for performing channel estimation by the terminal based on the received power measurement report; And transmitting a resource to which data is mapped based on the measurement set, to the terminal.

In order to achieve the above technical problem, a method for receiving downlink data in a wireless communication system according to the present invention includes: receiving information of a resource management set including information of a CSI-RS for receiving power measurement from a central control apparatus; ; Transmitting a received power measurement report of the CSI-RS corresponding to the resource management set to the central control apparatus; And restoring the data by receiving a resource to which data is mapped based on the measurement set including information of the CSI-RS determined for channel estimation according to the received power measurement report, from the central control apparatus.

In order to achieve the above technical problem, a downlink data transmission apparatus of a wireless communication system according to the present invention includes a communication unit for transmitting and receiving data with a terminal; And transmitting the information of the resource management set including the CSI-RS information for measuring the received power of the terminal to the terminal, and based on the received power measurement report of the CSI-RS corresponding to the resource management set received from the terminal. The control unit determines a measurement set including information of the CSI-RS for the terminal to perform channel estimation, and transmits a resource mapped data to the terminal based on the measurement set.

In order to achieve the above technical problem, a downlink data receiving apparatus of a wireless communication system according to the present invention includes a communication unit for transmitting and receiving data with a central control apparatus for transmitting the downlink data; And receiving information of a resource management set including information of CSI-RS for receiving power measurement from the central control apparatus, and transmitting a received power measurement report of the CSI-RS corresponding to the resource management set to the central control apparatus. And a control unit for restoring the data by receiving a resource to which data is mapped from the central control unit based on a measurement set including information of CSI-RS determined for channel estimation according to the received power measurement report.

According to the present invention, in a cellular wireless communication system, adjacent cells may transmit data by cooperating with each other through inter-cell cooperative transmission (CoMP) for a terminal located at a cell edge.

In addition, in a cellular wireless communication system, cells may provide an enhanced wireless communication service as compared to the case where there is no cooperation. When the terminal exists at the cell edge, the terminal may dynamically determine a cell to which data is to be received.

In addition, a plurality of cells simultaneously transmit information to a terminal existing at a cell edge, thereby increasing the information reception rate of the terminal. Through this, all terminals in the cellular mobile communication system can obtain a high data rate evenly regardless of their location in the cell.

In addition, the present invention is effective by classifying the type of CSI-RS resources in the wireless communication system using the CoMP scheme and then performing CSI-RS channel measurement on a specific CSI-RS resource and simultaneously receiving the PDSCH signal. It has the effect of enabling transmission and reception of downlink data.

1 is a view showing a structure of a radio frame (radio frame) of the LTE-A system,
2 is a diagram illustrating a cellular wireless communication system in which a transmit / receive antenna is disposed at the center of each cell according to the prior art;
3 is a diagram illustrating an example in which a CSI-RS is allocated in a resource block transmitted from a base station to a terminal in an LTE-A system according to the prior art;
4 is a diagram schematically illustrating a structure of a cellular wireless communication system according to an embodiment of the present invention;
5A and 5B are diagrams illustrating an example of a CSI-RS resource location allocated to a resource block by a central control apparatus for CSI-RSRP generation and reporting of a terminal according to an embodiment of the present invention, respectively. A flowchart illustrating a process of allocating a resource management set to a terminal and determining a CSI-RS resource to be used for channel estimation and feedback generation through a CSI-RSRP report;
6 shows a first embodiment of data mapping,
7A and 7B illustrate a PDSCH resource mapping process for applying a rate matching scheme to all CSI-RS resources allocated by a UE according to Embodiment 1;
8 shows a second embodiment of data mapping;
9A and 9B illustrate rate matching for CSI-RS resources included in a CoMP measurement set among CSI-RS resources allocated by a UE according to Embodiment 2, and corresponding CSI-RS resources for CSI-RS resources that are not. Figure showing the process of mapping the PDSCH as it is,
10 shows a third embodiment of data mapping;
11A and 11B illustrate a case in which a UE directly sets whether to apply rate matching to CSI-RS resources allocated according to Embodiment 3 through an RRC signal;
12 is a diagram showing the configuration of an apparatus for receiving downlink data, that is, a terminal according to an embodiment of the present invention;
FIG. 13 is a diagram illustrating a configuration of a downlink data transmission device, that is, a central control device according to an embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with the accompanying drawings. In addition, in describing the present invention, when it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. Terms to be described later are terms defined in consideration of functions in the present invention, and may be changed according to intentions or customs of users or operators. Therefore, the definition should be made based on the contents throughout the specification.

Further, in describing the embodiments of the present invention in detail, an OFDM-based wireless communication system, in particular, the 3GPP EUTRA standard will be the main target, but the main subject of the present invention is another communication system having a similar technical background and channel type. In addition, it is possible to apply with a slight modification in the range without departing greatly from the scope of the present invention, which will be possible in the judgment of those skilled in the art.

1 is a diagram illustrating a structure of a radio frame of an LTE-A system to which the present invention is applied.

Referring to FIG. 1, one transport frame is composed of 10 subframes, and each subframe is composed of two slots. Each subframe has an index of 0 to 9 in one transport frame, and each slot has an index (# 0 to # 19) of 0 to 19 as shown in FIG.

2 is a diagram illustrating a cellular wireless communication system in which a transmit / receive antenna is disposed at the center of each cell according to the prior art.

Referring to FIG. 2, in a cellular wireless communication system composed of a plurality of cells, a specific user equipment (UE) uses a wireless communication service using various methods described above from a single cell selected for a long period of time (semi-static). To be provided.

For example, a cellular wireless communication system may consist of three cells, cell 100, cell 110, and cell 120. The cell 100 may provide a wireless communication service to the terminal 101 and the terminal 102 located in the cell, the cell 110 may provide the wireless communication service to the terminal 111, and the cell 120 to the terminal 121. Reference numerals 130, 131, and 132 may be base stations (Evolved Node B: ENB) of cells 100, 110, and 120, respectively.

The terminal 102 receiving the wireless communication service in the cell 100 has a relatively longer distance from the base station 130 than the terminal 101. In addition, since the terminal 102 suffers from a large interference from the base station 132 of another cell 120, the data rate supported by the cell 100 is relatively low.

When the wireless communication service is independently provided to each other in cells 100, 110, and 120 as shown in the example shown in FIG. 2, each of the base stations 130, 131 for each UE 101, 102, 111, 121 to measure the downlink channel state per cell 132 transmits a reference signal (RS) for channel estimation. In addition, in the 3GPP LTE-A system, each of the terminals 101, 102, 111, and 121 uses the channel status information reference signal (CSI-RS) transmitted by the base stations 130, 131, and 132. , And measures the channel state between the 132 and the terminal 101, 102, 111, 121.

3 is a diagram illustrating an example in which a CSI-RS is allocated in a resource block transmitted from a base station to a terminal in an LTE-A system according to the prior art. The description of each signal allocated to the resource block in FIG. 3 is as shown in FIG. 3, and a detailed definition follows the relevant standard of the LTE-A system.

Referring to FIG. 3, signals for two CSI-RS antenna ports may be transmitted at respective positions 200 to 219. For example, the base station may transmit the two ports of the CSI-RS for the downlink measurement to the terminal at the position 200.

As illustrated in FIG. 2, in the cellular wireless communication system composed of a plurality of cells, different positions in a resource block may be allocated for CSI-RS transmission for each cell. For example, in the case of the cell 100 illustrated in FIG. 2, the CSI-RS may be transmitted at the position 200 of FIG. 3, the position 205 of the cell 110, and the position 210 of the cell 120.

As such, allocating time and frequency resources for CSI-RS transmission at different locations for each cell is to prevent CSI-RSs transmitted from different cells from generating mutual interference. The location of each CSI-RS resource in the above-described resource block is determined by resourceConfig information, which is a parameter transmitted from the base station to the terminal as a radio resource control (RRC) signal in a higher layer.

값에 의해 결정된다. 단말은

를 수신하면 다음의 표 1을 기초로 CSI-RS가 전송되는 서브프레임의 주기

와, CSI-RS가 전송되는 서브프레임의 오프셋

을 결정한다.In the downlink, the subframe in which the CSI-RS is transmitted is mapped to the subframeConfig information, which is a parameter transmitted as an RRC signal.

Determined by the value. The terminal

When receiving the period of the subframe in which the CSI-RS is transmitted based on the following Table 1

And the offset of the subframe in which the CSI-RS is transmitted.

Determine.

CSI-RS-SubframeConfig

CSI-RS Cycle

(Subframe) CSI-RS Subframe Offset

(Subframe) 0-4 5

5-14 10

15-34 20

35-74 40

75-154 80

Accordingly, the UE receives the CSI-RS in a subframe that satisfies Equation 1 below.

In Equation 1, n _f represents a transport frame number, and n _s represents a slot number within a transport frame.

On the other hand, in the cellular wireless communication system shown in Figure 2, the terminal located at the edge of the cell has a limit in being supported by a high data rate due to the large interference from other cells. That is, in the cellular wireless communication system as shown in FIG. 2, a transmission rate of a high speed data service provided to terminals existing in a cell is greatly affected by the position of the terminal in the cell. Therefore, the conventional cellular wireless communication system can transmit and receive data at a high data rate in the case of a terminal located relatively close to the center of the cell, but it is difficult to guarantee a high data rate in the case of a terminal located relatively far.

As described above, the cellular wireless communication system is constructed by constructing a plurality of cells in a limited area, and each cell provides a wireless communication service to terminals in the cell by a base station dedicated to wireless communication in the cell. In this case, the specific terminal is supported with the wireless communication service only from one cell determined semi-statically. Hereinafter, such a wireless communication system will be referred to as a non-CoMP system in comparison with a CoMP system.

As mentioned above, in the non-CoMP system, the high data rate provided to all terminals existing in a cell varies greatly depending on the position of the terminal in the cell. That is, the terminal located in the center of the cell may receive a high data rate, but the terminal located relatively close to the cell edge may not receive a high data rate.

In contrast, the CoMP system is a system in which a plurality of cells cooperate with each other to transmit data in order to support a higher data service of a terminal located at a cell edge. In this case, an enhanced wireless communication service may be provided in the entire cell area in preparation for the non-CoMP system.

The present invention relates to a dynamic cell selection (DS) scheme, a dynamic cell selection with dynamic blanking (DS / DB) scheme, and a joint transmission (JT) scheme, among other CoMP systems. Considering the case of using a scheduling and coordinated beamforming (CS / CB) scheme, a UE is allocated a plurality of CSI-RSs in a resource region and then considers a downlink physical shared channel (Physical Downlink Shared) An apparatus and method for receiving a channel (PDSCH) are proposed.

The DS method refers to a method in which a terminal measures channel states of a plurality of cells and transmits feedback to the base station, and the base station dynamically selects a cell to transmit downlink data to the terminal and transmits the data. In addition, the DS / DB method refers to a method in which a specific cell does not transmit data in order to reduce interference that a specific cell affects another cell. The JT method is a method of simultaneously transmitting data to a specific terminal from multiple cells. it means. In addition, the CS / CB method refers to a method of selecting a frequency resource and a precoding method in a direction of minimizing interference to an adjacent cell when performing data transmission scheduling of the UE.

According to the present invention, a UE is allocated a plurality of CSI-RS measurement resources and uses a plurality of allocated CSI-RSs to efficiently apply DS, DS / DB, JT, or CS / CB schemes to an LTE-A system. In consideration of this, an apparatus and method for receiving a PDSCH are proposed.

However, the present invention is not limited to DS, DS / DB, JT, or CS / CB scheme in LTE-A system, and a plurality of cells (base stations) can cooperatively transmit data to a terminal located at a cell edge. It can be applied to various wireless communication systems.

4 is a diagram schematically illustrating a structure of a cellular wireless communication system according to an embodiment of the present invention.

In FIG. 4, the cellular wireless communication system will be described on the assumption of three cell 300, 310, and 320 for convenience of description. A cell defined in an embodiment of the present invention refers to a data transmission area that can be serviced by a specific transmission point, and each transmission point is a macro base station and a cell identifier (cell-ID) in a macro area. It may be a remote radio head (RRH) in common or a macro cell or a pico cell in which each transmission point has a different cell-ID.

In addition, in the embodiment of the present invention, the central control device refers to a device such as a base station capable of transmitting and receiving data with a terminal and processing the transmitted and received data. In this case, when each transmission point is an RRH having a cell identifier and a cell identifier in common, the macro base station may be a central control apparatus. In addition, when each transmission point is a macro cell or a pico cell having a different cell identifier, a separate central control apparatus for integrating and managing each cell may be defined.

Referring to FIG. 4, the cellular wireless communication system performs CoMP transmission from terminals 301, 311, 321, and cells 300, 310, 320 that receive data from at least one cell 300, 310, 320, or the closest cell. It includes a terminal 302 for receiving data. Terminals 301, 311, and 321 receiving data from the closest cell each estimate a channel through a reference signal for channel estimation, ie, CSI-RS, for the cell where they are located, and include the channel estimation result. The feedback information is transmitted to the central controller 330. In FIG. 4, reference numerals 331, 332, and 333 are base stations (transmission points) of cells 300, 310, and 320, respectively, and each of the base stations 331, 332, and 333 may communicate with the central control apparatus 330.

However, in FIG. 4, the terminal 302 receiving data transmitted through the CoMP scheme from the three cells 300, 310, and 320 is channel state of each cell through the CSI-RS for each cell transmitted from all three cells 300, 310, and 320. Estimates and transmits feedback information including the channel estimation result to the central control apparatus 330. That is, the central controller 330 allocates three CSI-RS resources corresponding to each cell 300, 310, and 320 to a resource block transmitted to the terminal 302 to generate channel estimation and feedback information performed by the terminal 302. Receive feedback information.

Here, the central controller 330 may perform a process for determining a terminal to operate as CoMP and a terminal to operate as non-CoMP.

That is, the central controller 330 allocates one CSI-RS resource to a specific terminal for generating channel feedback information to perform non-CoMP operation, or allocates two or more CSI-RS resources for generating channel feedback information to CoMP. You can make an operation perform. Alternatively, the central control apparatus 330 may perform an operation of adding or excluding CSI-RS resources for generating feedback information in consideration of CoMP operation of the mobile terminal.

To this end, the central control apparatus 330 may collect downlink channel information from various cells around the terminal in a simpler manner than a series of operations in which the terminal estimates a channel through the CSI-RS resource, generates channel feedback information, and performs feedback. have.

In order to manage the CSI-RS resource for generating channel feedback information to be allocated to a specific terminal by the central control apparatus 330, the central control apparatus 330 first allocates several CSI-RS resources to the terminal and then assigns the CSI-RS allocated to the terminal. CSI-RS received power (CSI-RSRP) can be reported.

Since the UE only needs to measure the reception strength of the CSI-RS for CSI-RSRP reporting, it requires very small UE measurement complexity compared to the case of generating the channel feedback information, and the CSI-RSRP changes in a short term period. It is not a value but a value that is changed for a long term and does not require a separate reporting channel, so it may be included in uplink data transmission every long time and reported as higher information.

As described above, a set including information on resources allocated to at least one CSI-RS for UE CSI-RSRP reporting or a set including information on cells corresponding to the CSI-RS resources is included in a resource management set. set). Hereinafter, a process in which the central control apparatus allocates a resource management set including a plurality of CSI-RS resources and the CSI-RSRP report is performed accordingly by referring to FIGS. 5A and 5B will be described in detail.

FIG. 5A illustrates an example of a CSI-RS resource location allocated to a resource block by a central control apparatus 330 for CSI-RSRP generation and reporting of a terminal according to an embodiment of the present invention. The description of each signal allocated to the resource block in FIG. 5A is as shown in FIG. 3, and a detailed definition follows the relevant standard of the LTE-A system. 5B is a flowchart illustrating a process in which the central control apparatus 330 allocates a resource management set to a terminal and determines a CSI-RS resource to be used for channel estimation and feedback generation through a CSI-RSRP report.

Referring to FIG. 5A, the central controller 330 may use the CSI-RS resources 401 and 402 for six cells around the terminal 302 such that the terminal 302 receiving CoMP transmission can measure downlink power strength from a sufficient number of neighbor cells. By assigning 403, 404, 405, and 406, the UE can receive each CSI-RS resource corresponding to six neighboring cells. This corresponds to step 510 of FIG. 5B.

That is, the central controller 330 allocates corresponding CSI-RS resources 401, 402, and 403 so that the terminal 302 can generate CSI-RSRP for the neighboring cells 300, 310, and 320 shown in FIG. The CSI-RS resources 404, 405, and 406 are allocated to other neighboring cells (not shown), so that the UE 302 can generate CSI-RSRP from enough neighboring cells and report it to the central controller 330. In this case, the resource management set may be expressed as a set of information of {401, 402, 403, 404, 405, 406} or corresponding cells.

In step 520 of FIG. 5B, the terminal transmits a CSI-RSRP report to the central control unit 330, and the central control unit 330 confirms CSI-RSRP values of various cells based on the CSI-RSRP report of the terminal, in step 530 of FIG. 5B. By comparing the DL received power values for each cell of the UE, the UE 302 actually determines the CSI-RS resource to be used for channel estimation and feedback generation. Thereafter, in step 540 of FIG. 5B, the central control apparatus 330 notifies the terminal of the determined CSI-RS resource.

For example, the central controller 330 determines the cells having the CSI-RSRP included in a specific threshold based on the cell having the largest CSI-RSRP as the cells for which the UE will actually perform channel estimation and feedback generation. The UE informs the CSI-RS resource corresponding to the determined cells as a resource for performing channel estimation and feedback generation. Here, the specific reference value may be set to an appropriate value by the CoMP system at a value of about 6 dB to about 10 dB.

In FIG. 5A, if the terminal 302 is allocated the CSI-RSRP to report the CSI-RSRP, the CSI-RS for the channel estimation and feedback generation of the terminal by the central controller 330 among the CSI-RS resources 401, 402, 403, 404, 405, and 406. If the resource determined as the resource is 401, 402, or 403, the central controller 330 notifies the terminal of the determined CSI-RS resources 401, 402, and 403. That is, the central controller 330 is configured for the CSI-RS resource 401 and the cell 310 for channel estimation and feedback generation for the cell 300 so that the terminal 302 estimates a channel from the three cells 300, 310, and 320 and generates feedback. The UE informs the UE of the CSI-RS resource 402 for channel estimation and feedback generation, and the CSI-RS resource 403 for channel estimation and feedback generation of the cell 320.

As described above, a set including information on at least one CSI-RS resource allocated for channel estimation and feedback information generation for each cell of the terminal or a set including information on cells corresponding to the CSI-RS resource is measured. measurement set). Therefore, in the case described above, the measurement set may be expressed as {401, 402, 403} or {300, 310, 320}.

In the example of FIG. 5A and FIG. 5B, the case in which the CoMP measurement set is set to a subset of the CoMP resource management set has been described. However, the present invention is not limited thereto, and a separate CSI not included in the CoMP resource management set is included in the CoMP measurement set. -RS resource may be included.

As an example, when the central control unit 330 receives the CSI-RSRP for the CSI-RS resources in the CoMP resource management set and determines that the JT is to be supported for two specific cells, the JT situation of the two cells is separate. The channel feedback information may be requested by allocating CSI-RS resources.

As described above, the UE may be allocated a plurality of CSI-RS resources from the central control apparatus 330, and the corresponding CSI-RS resources may be included in a CoMP resource management set, a CoMP measurement set, or both sets, respectively.

Hereinafter, when the terminal has been allocated a plurality of CSI-RS resources by the above-described process, the central control apparatus 330 maps the data symbols to the PDSCH transmission resources in consideration of this, and transmits the data symbols to the PDSCH on the assumption of the mapping method. It will be described in detail how to receive.

<Example 1>

The simplest way to define PDSCH transmission resources when several CSI-RS resources are allocated in a resource block transmitted to the UE is to define that PDSCH is not transmitted to all time frequency resources to which CSI-RS resources are allocated.

FIG. 6 is a diagram illustrating Embodiment 1 mapping a PDSCH symbol. FIG. Referring to FIG. 6, the central control apparatus maps PDSCH symbols, that is, data from low index resources, in order, and resource positions to which CSI-RSs (CSI-RS-1 and CSI-RS-2) allocated by the UE are mapped. You can always skip and map the next PDSCH symbol from the next frequency resource. Here, the CSI-RSs allocated by the UE (CSI-RS-1, CSI-RS-2) may be CSI-RSs corresponding to the aforementioned resource management set.

As such, a method of skipping a specific resource and mapping PDSCH symbols in sequence may be referred to as a rate matching method. That is, when multiple CSI-RS resources are allocated, the first method of defining PDSCH transmission resources is whether all CSI-RSs are allocated regardless of whether the CSI-RI allocated by the UE belongs to a resource management set or a measurement set. The rate matching method is applied to resources. Accordingly, the central control unit is not included in the resource management set but not included in the measurement set, and thus does not perform data mapping on all of the CSI-RSs allocated only for the reception power measurement of the terminal.

7A and 7B are diagrams illustrating a PDSCH resource mapping process for applying a rate matching scheme to all CSI-RS resources allocated by a UE according to the first embodiment.

First, referring to FIG. 7A, in step 710, the central control apparatus determines whether a CSI-RS allocated to a UE is mapped to a resource location to which a PDSCH symbol is mapped in a resource block. If it is determined that the CSI-RS allocated to the terminal is not mapped to the corresponding position, the PDSCH symbol is mapped to the corresponding position in step 715. If the CSI-RS allocated to the terminal is mapped, the PDSCH symbol is not mapped to the corresponding position.

Next, the above process will be described in more detail with reference to FIG. 7B. First, in step 750, the central control apparatus initializes the resource index to 0 to start mapping of PDSCH resources to a specific terminal. If the PDSCH resource index starts from 1, the resource index is initialized to 0. However, embodiments of the present invention are not limited thereto. If the PDSCH resource index starts with a natural number n, the resource index is initialized to n-1.

In step 755, the central control apparatus increases the resource index by one step and, in step 760, checks whether the CSI-RS allocated by the terminal is mapped to the resource of the corresponding index.

If it is determined in step 760 that the CSI-RS allocated by the UE is mapped to the resource of the corresponding index, the central control apparatus proceeds to step 770 without mapping the PDSCH symbol to the resource of the corresponding index. That is, it is checked whether mapping of PDSCH symbols to resources of all indexes is completed. If it is determined that the current resource index is the last, the PDSCH mapping is completed. If not, the process returns to step 755.

If it is determined in step 760 that the CSI-RS allocated by the UE is not mapped to the resource of the corresponding index, the central control apparatus proceeds to step 765 and maps the PDSCH symbol to the resource of the corresponding index. Check whether the index is the last one. If it is determined that the current resource index is the last, the PDSCH mapping is completed. If not, the process returns to step 755.

7B illustrates a case in which the central control apparatus determines whether CSI-RI is mapped to the resource of the current index while sequentially increasing the resource index, but the present invention is not limited thereto. After obtaining CSI-RS mapping information for all index resources before starting, it is also possible to exclude PDSI mapped to all resources except CSI-RS mapped indexes in advance.

Upon receiving the PDSCH with data mapping according to the mapping process of the first embodiment described above, the UE may restore the PDSCH data by assuming that the central control apparatus uses the resource mapping method according to the first embodiment.

<Example 2>

As a second method of defining PDSCH transmission resources when a plurality of CSI-RS resources are allocated in a resource block transmitted to the UE, rate matching described above is applied to the CSI-RS resources included in the CoMP measurement set. For CSI-RS resources that are not present, PDSCH symbols may be mapped to locations of corresponding CSI-RS resources.

FIG. 8 is a diagram illustrating Embodiment 2 of mapping a PDSCH symbol. FIG. Referring to FIG. 8, the central control apparatus sequentially maps PDSCH symbols from resources of a low index, and the resources of a specific index correspond to CSI-RS resources (CSI-RS-3) allocated by the UE and are included in a CoMP measurement set. In this case, the PDSCH symbol mapping is skipped and the next PDSCH symbol is mapped to the corresponding resource.

On the other hand, if the time frequency resource of a specific index corresponds to the CSI-RS resource (CSI-RS-4) allocated by the corresponding UE but is not included in the CoMP measurement set, the central control unit indexes the index regardless of the CSI-RS allocation. PDSCH symbol may also be mapped to the resource of.

In the case of a resource defined such that CSI-RS and PDSCH are simultaneously mapped, the UE may simultaneously perform CSI-RS channel estimation and PDSCH reception on the corresponding resource, but CSI-RS channel estimation is performed on the corresponding resource and PDSCH For reception, decoding may be performed assuming a value of a corresponding resource as zero. The method of decoding assuming that the resource is zero may be called puncturing.

9A and 9B illustrate rate matching for CSI-RS resources included in a CoMP measurement set among CSI-RS resources allocated by a UE according to Embodiment 2, and corresponding CSI-RS resources for CSI-RS resources that are not. Is a diagram illustrating a process of mapping a PDSCH as it is.

First, referring to FIG. 9A, in step 910, the central control apparatus determines whether a CSI-RS allocated to a terminal is mapped to a resource location to which a PDSCH symbol is mapped in a resource block. If it is determined that the CSI-RS allocated to the terminal is not mapped to the corresponding position, the PDSCH symbol is mapped to the corresponding position in step 920.

If the CSI-RS allocated to the terminal is mapped to the corresponding location in step 910, the central control apparatus determines whether the mapped CSI-RS is included in the CoMP measurement set in step 915. If it is determined that the mapped CSI-RS is not included in the CoMP measurement set, the PDSCH symbol is mapped to the corresponding position in step 920.

On the other hand, the CSI-RS mapped in step 915 is determined to be included in the CoMP measurement set, the central control unit does not map the PDSCH symbol to the location.

Next, the above process will be described in detail with reference to FIG. 9B. First, in step 950, the central control apparatus initializes the resource index to 0 to start mapping of the PDSCH resource to the terminal. If the PDSCH resource index starts from 1, the resource index is initialized to 0. However, embodiments of the present invention are not limited thereto. If the PDSCH resource index starts with a natural number n, the resource index is initialized to n-1.

Thereafter, in step 955, the central control apparatus increases the resource index by one step and, in step 960, checks whether the CSI-RS allocated by the terminal is mapped to the resource of the corresponding index.

If it is determined in step 960 that the CSI-RS allocated by the UE is not mapped to the resource of the corresponding index, the central control apparatus proceeds to step 970 and maps the PDSCH symbol to the resource of the corresponding index. Make sure you are at the end of the index. If it is determined that the current resource index is the last, the PDSCH mapping is terminated. Otherwise, the process returns to step 955.

On the other hand, if it is determined in step 960 that the CSI-RS allocated by the UE is mapped to the resource of the corresponding index, the central control apparatus proceeds to step 965 to determine whether the CSI-RS mapped to the resource of the current index is included in the CoMP measurement set. To judge.

If it is determined in step 965 that the mapped CSI-RS is included in the CoMP measurement set, the central control unit does not map the PDSCH symbol to the resource of the corresponding index and checks whether the current index is the last of the resource index in step 975 and then the resource index. If is the last time the PDSCH mapping is finished, otherwise, return to step 955.

If it is determined in step 965 that the mapped CSI-RS is not included in the CoMP measurement set, the central controller proceeds to step 970 and maps the PDSCH symbol to the resource of the corresponding index. If the resource index is the last, PDSCH mapping is finished. Otherwise, the process returns to step 955.

9B illustrates a case in which the central control device sequentially increases the resource indexes and determines whether the CSI-RSs are mapped to the resources of the current index and included in the CoMP measurement set. However, the present invention is not limited thereto. After the central control unit acquires CSI-RS mapping information for resources of all indexes before initiating PDSCH mapping, maps PDSCH to remaining resources except for all indexes mapped to CSI-RS belonging to the CoMP measurement set in advance. You can also do it.

Upon receiving the resource block to which the PDSCH symbol is mapped according to the mapping process of Embodiment 2 described above, the UE may restore PDSCH data by assuming that the central control apparatus uses the resource mapping method according to Embodiment 2.

Hereinafter, a process of recovering PDSCH data according to Embodiment 2 by receiving information of a CoMP measurement set from a central control unit in detail will be described.

According to the second embodiment, the resource management set, which is a set of CSI-RS information received from the central control apparatus by the terminal, is {CSI-RS-1, CSI-RS-2, CSI-RS-3, CSI-RS-4 , CSI-RS-5}, of which CSI-RS-1 and CSI-RS-2 are included in the CoMP measurement set, and the remaining CSI-RS-3, CSI-RS-4, and CSI-RS-5 are CoMP measurements. If not included in the set, the PDSCH is not transmitted and the rate matching is applied in the time frequency resource in which the CSI-RS-1 and the CSI-RS-2 are transmitted, but the remaining CSI-RS-3, CSI-RS-4, CSI- For RS-5, PDSCH symbols are mapped and transmitted on a corresponding resource regardless of the mapped CSI-RS.

Therefore, in order to apply the second embodiment of the present invention, it is necessary to share whether a specific CSI-RS is included in the CoMP measurement set between the central control apparatus and the terminal.

In the LTE-A system, the central control apparatus transmits CSI-RS reception information to the terminal by using the RRC signal. The CSI-RS reception information included in the RRC signal may include at least one of the following information.

Receive CSI-RS information:

csi-RS-Identity: index of the corresponding CSI-RS

antennaPortsCount: The number of antenna ports of the CSI-RS.

resourceConfig: location of the corresponding CSI-RS in the resource block shown in FIG.

subframeConfig: Transmission timing information of the corresponding CSI-RS shown in Table 1.

scramblingIdentity: Sequence generation information of the corresponding CSI-RS

That is, when the UE checks one set of RRC information as described above, one CSI-RS is defined accordingly, and when receiving several sets of RRC information, several different CSI-RSs are allocated.

Meanwhile, the central control apparatus may allocate additional resources for measuring interference to the terminal in addition to the CSI-RS allocation for channel estimation and feedback information generation. The amount of data per hour that the terminal can receive is affected by the magnitude of the interference as well as the signal strength. Accordingly, the central control apparatus may separately allocate one or several interference measurement resources (CSI-IM) for which the terminal can measure only interference for accurate interference measurement of the terminal.

That is, the central control apparatus may allocate one CSI-IM to one terminal to allow the terminal to measure the amount of interference commonly applied to signal components for the CSI-RS used for generating feedback, or to one terminal. CSI-IM may be allocated to allow the UE to measure various interference situations. In the same manner as the CSI-RS allocation, in the LTE-A system, the central control apparatus transmits the CSI-IM reception information to the terminal by using the RRC signal. The CSI-IM reception information included in the RRC signal may include at least one of the following information.

CSI-IM Receive Information:

csi-im-Identity: index of the corresponding CSI-IM

resourceConfig: location of the corresponding CSI-IM in the resource block shown in FIG.

subframeConfig: Transmission timing information of the corresponding CSI-IM shown in Table 1.

That is, when the UE checks one set of RRC information as described above, one CSI-IM is defined accordingly, and when several sets of RRC information are received, several different CSI-IMs are allocated.

As described above, when the UE is allocated one or more CSI-RSs and also is allocated one or more CSI-IMs, feedback information for a specific cell and an interference situation may be defined. In LTE-A, feedback assignment is also made via RRC signals.

A unit for allocating feedback to a terminal by a base station is called a CSI process, and one CSI process is associated with one CSI-RS and one CSI-IM. The CSI process allocation information, which is feedback allocation information included in the RRC signal in LTE-A, may include at least one of the following information.

Receive CSI process information:

csi-Process-Identity: index of the CSI process

csi-RS-Identity: index of CSI-RS to be used as channel information of feedback generation

csi-IM-Identity: index of CSI-IM to be used as interference information of feedback generation

Pc: power scaling information to consider when generating feedback

CodebookSubsetRestrictions: Precoding information to consider when generating feedback

That is, when the terminal confirms one set of RRC information as described above, one CSI process is defined, and the user is informed to generate one feedback information. When receiving a plurality of sets of RRC information, the UE is assigned a plurality of different CSI process and a plurality of feedback corresponding thereto.

Here, as a first method in which the central control unit and the terminal can share whether a specific CSI-RS is included in the CoMP measurement set, the terminal is a CSI-RS referenced to one or more CSI processes allocated from the central control unit. For example, the CSI-RSs included in the feedback allocation information received from the central control unit are the CSI-RSs used for generating channel feedback, and thus may be determined to be included in the CoMP measurement set and not referred to the assigned CSI process. Since the -RSs are not used for generating the channel feedback, it can be determined that they are not included in the CoMP measurement set.

For example, the set of CSI-RSs allocated by the UE through the RRC signal is {CSI-RS-1, CSI-RS-2, CSI-RS-3, CSI-RS-4, CSI-RS-5}. The terminal may be allocated one CSI-IM from the central control apparatus. In addition, the UE may be allocated three CSI processes as shown in Table 2 below to allocate feedback.

Signal component Interference CSI process 1 CSI-RS-1 IMR CSI process 2 CSI-RS-2 IMR CSI process 3 CSI-RS-3 IMR

According to Table 2, the UE can confirm that the CSI-RS-1, CSI-RS-2, and CSI-RS-3 referred to the CSI process allocation are included in the CoMP measurement set, and the remaining CSI-RS-4 and CSI- RS-5 determines that it is not included in the CoMP measurement set, and thus, it may be confirmed that rate matching is not applied to PDSCH mapping for CSI-RS-4 and CSI-RS-5. When using the method of determining whether the CSI processes are included in the CoMP measurement set or not, the steps 915 of FIG. 9A and step 960 of FIG. 9B indicate that the mapped CSI-RSs are assigned CSI processes. Was it referenced in at least one of them? ” Or "is the information of the mapped CSI-RS included in the feedback allocation information received by the UE?"

For reference, a method of determining whether a mapped CSI-RS is included in a CoMP measurement set based on whether it is referenced in CSI processes is also applied to LTE Release 10 CSI-RS, which cannot be included in the CSI process allocation. 10 CSI-RS may be defined as always included as part of the CoMP measurement set.

As another method in which the central control unit and the terminal can share whether a specific CSI-RS is included in the CoMP measurement set, the central control unit corresponds to the RRC signal for setting the CSI-RS delivered to the terminal. May include control information directly indicating whether is included in the CoMP measurement set. In this case, the RRC signal information including the CSI-RS reception information may be modified as follows.

Receive CSI-RS information:

csi-RS-Identity: index of the corresponding CSI-RS

antennaPortsCount: The number of antenna ports of the CSI-RS.

resourceConfig: location of the corresponding CSI-RS in the resource block shown in FIG.

subframeConfig: Transmission timing information of the corresponding CSI-RS shown in Table 1.

scramblingIdentity: Sequence generation information of the corresponding CSI-RS

-CoMPmeasurementSet: information about inclusion in CoMP measurement set (control information)

That is, the UE may determine whether the corresponding CSI-RS is included in the CoMP measurement set according to whether CoMPmeasurementSet information is set in the above RRC information, and may determine that PDSCH resource mapping is performed according to the processes of FIGS. 9A and 9B. .

For reference, since CoMPmeasurementSet information cannot be included in the CSI-RS configuration until LTE Release 11, which is already defined, Release 10 or Release 11 CSI-RSs may be defined as always included as part of the CoMP measurement set.

As a third method in which the central control apparatus and the terminal share whether a specific CSI-RS is included in the CoMP measurement set, an RRC signal for configuring the CoMP measurement set and the CoMP resource management set may be defined separately from the CSI-RS configuration. .

That is, an RRC signal including the following control information may be newly defined separately from the CSI-RS configuration.

CoMP resource management set information:

csi-RS-Identity: index of CSI-RS included in CoMP resource management set

CoMP Measurement Set Information:

csi-RS-Identity: index of CSI-RS included in CoMP measurement set

When this method is applied, the UE can directly check the CSI-RS included in the CoMP measurement set through the RRC signal, and confirm the PDSCH resource mapping method by applying FIGS. 9A and 9B.

According to the second embodiment of the present invention described above, only the CSI-RSs included in the CoMP measurement set are considered, and the reason for mapping the PDSCH symbol irrespective of other CSI-RSs is because CSI- without channel estimation and feedback. Since the PDSCH is not directly transmitted due to the lack of downlink channel information in a cell related to RS, applying rate matching to a corresponding resource may cause a waste of data resources. In addition, even if rate matching is not applied, since CSI-RS is transmitted in the entire frequency domain, even if it is partially transmitted with the PDSCH, it is determined that the downlink power measurement will not be significantly affected.

<Example 3>

As a third method of defining PDSCH transmission resources when a plurality of CSI-RS resources are allocated in a resource block transmitted to the UE, the central control apparatus directly determines whether to apply rate matching to a specific CSI-RS resource. A signal may be set and, accordingly, PDSCH resource mapping may be determined.

FIG. 10 is a diagram showing Embodiment 3 of mapping a PDSCH symbol. FIG. Referring to FIG. 10, the central control apparatus sequentially maps PDSCH symbols from resources of a low index, while a resource of a specific index corresponds to a CSI-RS resource (CSI-RS-5) allocated by the UE, and the CSI-RS resource is When the rate matching is applied through the RRC signal, the PDSCH symbol mapping may be skipped to the resource of the index and the next PDSCH symbol may be mapped from the next frequency resource.

On the other hand, if a time frequency resource of a specific index corresponds to a CSI-RS resource (CSI-RS-6) allocated by the UE, but this CSI-RS resource is not configured to apply rate matching through an RRC signal, The PDSCH symbol may be mapped as it is regardless of the CSI-RS allocation to the resource.

As described above, in case of a resource defined that CSI-RS and PDSCH are simultaneously mapped, the UE may simultaneously perform CSI-RS channel estimation and PDSCH reception on the corresponding resource, but CSI-RS channel estimation is performed on the corresponding resource and PDSCH is performed. For reception, decoding may be performed assuming a value of a corresponding resource as zero. A method of decoding assuming that the resource is zero may be called puncturing.

11A and 11B illustrate a case in which a UE directly sets whether CSI-RS resources allocated to rate matching according to Embodiment 3 are applied through RRC signals.

First, referring to FIG. 11A, in step 1110, the central control apparatus determines whether a CSI-RS allocated to a UE is mapped to a resource location to which a PDSCH symbol is mapped in a resource block. As a result of determination, when the CSI-RS allocated to the terminal is mapped to the corresponding position, it is determined whether rate matching is applied to the mapped CSI-RS in step 1115.

If it is determined in step 1115 that the rate matching is not applied to the mapped CSI-RS, the central control apparatus maps the PDSCH symbol to the corresponding position in step 1120 and if it is determined that the rate matching is applied to the mapped CSI-RS. Do not map the PDSCH symbol to the location.

Next, the above process will be described in more detail with reference to FIG. 11B. First, in step 1150, the central control apparatus initializes the resource index to 0 to start mapping of PDSCH resources to a specific terminal. If the PDSCH resource index starts from 1, the resource index is initialized to 0. However, embodiments of the present invention are not limited thereto. If the PDSCH resource index starts from a natural number n, the resource index is initialized to n-1.

After that, in step 1155, the central control apparatus increases the resource index by one step and, in step 1160, checks whether the CSI-RS allocated by the terminal is mapped to the resource of the corresponding index.

If it is determined in step 1160 that the CSI-RS is not mapped to the corresponding resource, the central control apparatus proceeds to step 1170 and maps the PDSCH symbol to the resource of the corresponding index. In step 1175, it is determined whether the current index is the end of the resource index. Check it. If it is determined that the current resource index is the last, the PDSCH mapping is terminated. Otherwise, the process returns to step 1155.

On the other hand, if it is determined in step 1160 that the CSI-RS is mapped, the central controller proceeds to step 1165 and determines whether the CSI-RS mapped to the resource of the corresponding index is set to perform rate matching.

If the corresponding CSI-RS is configured to apply rate matching in step 1165, the central control apparatus does not map the PDSCH symbol to the resource of the corresponding index, checks whether the resource index is the last in step 1175, and if the current resource index is the last, the PDSCH Finish mapping and return to step 1155 if not.

If the corresponding CSI-RS is configured not to apply rate matching in step 1165, the central control apparatus proceeds to step 1170, maps a PDSCH symbol to a resource of the corresponding index, and checks the end of the resource index in step 1175. If the index is the last, the PDSCH mapping is completed, otherwise, the process returns to step 1155.

11B illustrates a case in which the central controller determines whether CSI-RS mapping and rate matching are applied to resources of the current index while sequentially increasing the resource index, but the present invention is not limited thereto. After the CSI-RS mapping information about the resources of all the indexes is obtained before the PDSCH mapping is started, the PDSCH is mapped to the remaining resources except for all indexes to which the CSI-RS to which rate matching is applied are pre-mapped. It is possible.

Upon receiving the resource block to which the PDSCH symbol is mapped according to the mapping process of Embodiment 3 described above, the UE restores PDSCH data by assuming that the central control apparatus uses the resource mapping method according to Embodiment 3.

According to the third embodiment, the set of CSI-RSs received from the UE by the central control unit is {CSI-RS-1, CSI-RS-2, CSI-RS-3, CSI-RS-4, CSI-RS- 5} of which CSI-RS-1 and CSI-RS-2 are set via RRC signals to apply rate matching, and the remaining CSI-RS-3, CSI-RS-4 and CSI-RS-5 are rate matching. If not set, the PDSCH is not transmitted and the rate matching is applied in the time frequency resource in which the CSI-RS-1 and CSI-RS-2 are transmitted, but the remaining CSI-RS-3, CSI-RS-4, and CSI-RS are applied. For -5, the PDSCH symbol is mapped and transmitted to the corresponding resource regardless of the mapped CSI-RS.

Therefore, in order to apply the third embodiment of the present invention, it is necessary to share whether rate matching is applied to a specific CSI-RS between the central control apparatus and the terminal.

As mentioned above, in the LTE-A system, the central control apparatus transmits CSI-RS reception information to the terminal by using the RRC signal. As an example of sharing whether the central control apparatus and the terminal apply rate matching for a specific CSI-RS according to Embodiment 3 of the present invention, the central control apparatus applies rate matching to an RRC signal to which the CSI-RS is allocated. The RRC signal including the rate matching information for setting whether or not may be added to the terminal. In this case, the CSI-RS reception information may include the following information.

Receive CSI-RS information:

csi-RS-Identity: index of the corresponding CSI-RS

antennaPortsCount: The number of antenna ports of the CSI-RS.

resourceConfig: location of the corresponding CSI-RS in the resource block shown in FIG.

subframeConfig: Transmission timing information of the corresponding CSI-RS shown in Table 1.

scramblingIdentity: Sequence generation information of the corresponding CSI-RS

rateMatching: Whether to apply rate matching to a corresponding CSI-RS resource (rate matching information)

That is, the UE determines whether to apply rate matching to the corresponding CSI-RS according to the setting of rateMatching information among the above-described RRC information, and determines PDSCH resource mapping according to the process of FIG. 11.

For reference, the rateMatcing information may not be included in the previously defined CSI-RS configuration until LTE Release 11, and thus may be defined as always applying rate matching to Release 10 or Release 11 CSI-RSs.

According to the third embodiment of the present invention described above, the central control apparatus separately sets whether the CSI-RS matches the rate, so that each base station can control the data resource utilization and the accuracy of the CSI-RSRP.

12 is a diagram illustrating a configuration of a downlink data receiving apparatus, that is, a terminal according to an embodiment of the present invention.

Referring to FIG. 12, the terminal may include a communication unit 1210 and a control unit 1220.

The communication unit 1210 performs a function of transmitting or receiving data from the outside. Here, the communication unit 1210 may estimate the channel through the CSI-RS allocated from the central control unit under the control of the control unit 1220 and additionally measure the feedback information or the power intensity, and transmit the information to the central control unit. have. It can also identify resource locations for data and additional channels and restore data.

The controller 1220 controls the states and operations of all the components constituting the terminal according to the embodiments shown in FIGS. 7A / 7B, 9A / 9B, and 11A / 11B. In particular, the controller 1220 may determine whether the PDSCH symbol is mapped to the CSI-RS resource location allocated by the UE.

The channel estimator 1221 checks the CSI-RS information received from the central control apparatus and accordingly estimates the channel using the received CSI-RS. In addition, the data receiver 1222 collects PDSCH symbols and restores data according to the method of Embodiments 1 to 3 described above.

Although the terminal according to the present invention has been described as being composed of the communication unit 1210 and the control unit 1220, the embodiment of the present invention is not limited thereto. That is, the terminal may further include various components according to the function performed in the terminal. For example, the terminal may further include a display unit for displaying a current state of the terminal, an input unit for inputting a signal such as performing a function from a user, and a storage unit for storing data generated in the terminal.

13 is a diagram showing the configuration of a central control apparatus according to an embodiment of the present invention.

Referring to FIG. 13, the central control apparatus may include a control unit 1310 and a communication unit 1320.

The controller 1310 controls the states and operations of all the components constituting the central control apparatus according to the embodiments shown in FIGS. 7A / 7B, 9A / 9B, and 11A / 11B. Herein, the control unit 1310 allocates a CSI-RS for each cell for downlink reception power or channel estimation of the terminal to a resource to be transmitted to the terminal, and checks the PDSCH transmission resource and maps data symbols in consideration of this. For this purpose, the controller 1310 may further include a resource allocator 1311.

The resource allocator 1311 allocates resources and timings for the UE to estimate channels for each cell, measures downlink power, and identifies PDSCH resources. At this time, PDSCH resources are mapped by determining whether to apply rate matching to a specific CSI-RS according to an appointment of a base station and a terminal.

The communication unit 1320 performs a function of transmitting and receiving data with a cell managed by the terminal or the central control apparatus. Herein, the communication unit 1320 transmits the CSI-RS and the PDSCH to the terminal under the allocated resources under the control of the control unit 1310.

Those skilled in the art will appreciate that the present invention can be embodied in other specific forms without changing the technical spirit or essential features of the present invention. Therefore, it should be understood that the embodiments described above are exemplary in all respects and not restrictive. The scope of the present invention is indicated by the scope of the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and the equivalent concept are included in the scope of the present invention. Should be interpreted.

On the other hand, the present specification and the drawings have been described with respect to the preferred embodiments of the present invention, although specific terms are used, it is only used in a general sense to easily explain the technical details of the present invention and help the understanding of the invention, It is not intended to limit the scope of the invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be carried out in addition to the embodiments disclosed herein.

Claims (16)

In the method performed by the base station of the communication system,
Transmitting configuration information including information on time-frequency resources for a channel state information reference signal (CSI-RS) to a terminal;
Obtaining a plurality of data symbols to be transmitted to the terminal;
Identifying resources for mapping the plurality of data symbols;
Mapping the plurality of data symbols to the identified resource; And
Transmitting the mapped plurality of data symbols to a terminal on a physical downlink shared channel (PDSCH),
Except when the CSI-RS is a CSI-RS for RSRP (reference signal received power) reporting using higher layer signaling, time-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Not characterized in that the method. The method of claim 1,
If the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling, resource management including received power information of the CSI-RS for RSRP reporting using the higher layer signaling from the terminal. Receiving a report for the method. The method of claim 1, wherein the configuration information includes at least one CSI-RS index when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling. The method of claim 1, wherein when the CSI-RS is a CSI-RS for feedback of channel state information, resource-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Not characterized in that the method. In the method performed by the terminal of the communication system,
Receiving configuration information including information on time-frequency resources for a channel state information reference signal (CSI-RS) from a base station;
Receiving downlink data on a physical downlink shared channel (PDSCH) from the base station;
Identifying a resource to which a plurality of data symbols of the downlink data is mapped;
Obtaining the plurality of data symbols based on the identified resources,
Except when the CSI-RS is a CSI-RS for RSRP (reference signal received power) reporting using higher layer signaling, time-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Not characterized in that the method. The method of claim 5,
Measuring the received power of the CSI-RS when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling;
And sending a report for resource management including the received power information of the CSI-RS to the base station. The method of claim 5, wherein the configuration information includes at least one CSI-RS index when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling. 6. The method of claim 5, wherein when the CSI-RS is a CSI-RS for feedback of channel state information, resource-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Not characterized in that the method. In a base station of a communication system,
A transceiver; And
Transmitting configuration information including information on time-frequency resources for channel state information reference signal (CSI-RS) to the terminal,
Acquire a plurality of data symbols to be transmitted to the terminal,
Identifying a resource for mapping the plurality of data symbols,
Map the plurality of data symbols to the identified resource,
A control unit connected to the transceiver to control the mapped plurality of data symbols to be transmitted to the terminal on a physical downlink shared channel (PDSCH),
Except when the CSI-RS is a CSI-RS for RSRP (reference signal received power) reporting using higher layer signaling, time-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Characterized in that the base station. The method of claim 9,
If the CSI-RS is CSI-RS for RSRP reporting using the higher layer signaling, the controller includes resource management including received power information of the CSI-RS for RSRP reporting using the higher layer signaling from the terminal. and further control to receive a report for resource management. 10. The base station of claim 9, wherein the configuration information includes at least one CSI-RS index when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling. 10. The method of claim 9, wherein when the CSI-RS is a CSI-RS for feedback of channel state information, resource-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Characterized in that the base station. In the terminal of the communication system,
A transceiver; And
Receiving configuration information including information on a time-frequency resource for a channel state information reference signal (CSI-RS) from a base station,
Receive downlink data on a physical downlink shared channel (PDSCH) from the base station,
Identify a resource to which a plurality of data symbols of the downlink data is mapped;
A control unit connected to the transceiver for controlling to obtain the plurality of data symbols based on the identified resources,
Except when the CSI-RS is a CSI-RS for RSRP (reference signal received power) reporting using higher layer signaling, time-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Characterized in that the terminal. The method of claim 13,
The controller measures the received power of the CSI-RS when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling.
And further control to transmit a report for resource management including the received power information of the CSI-RS to the base station. The terminal of claim 13, wherein the configuration information includes at least one CSI-RS index when the CSI-RS is a CSI-RS for RSRP reporting using the higher layer signaling. 15. The method of claim 13, wherein when the CSI-RS is a CSI-RS for feedback of channel state information, resource-frequency resources for the CSI-RS are not used to map the plurality of data symbols. Characterized in that the terminal.

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