KR20120080492A - Method and apparatus for transmitting and receiving aperiodic reference signal in communication systemwith multiple component carriers - Google Patents

Abstract

PURPOSE: A method and apparatus for transmitting and receiving an aperiodic reference signal in communication system with multiple component carriers are provided to efficiently transmit A-SRS(Aperiodic Sounding Reference Signal) in a multiple cellular environment by allocating an uplink and the A-SRS to different CC(Component Carrier)s. CONSTITUTION: A-SRS configuration parameter information(set table) for each CC is selectively transmitted to an A-SRS transmission device through separate signaling RRC(Radio Resource Control)(S1005). A SRS receiving device generates down link control information of a physical control channel including A-SRS transmission object element carrier wave identifying information. The SRS receiving device transmits the down link control information of the physical control channel to the SRS transmission device(S1010). The SRS transmission device receives A-SRS transmitted through A-SRS transmission object element carrier waves by using the A-SRS transmission object element carrier wave identifying information and A-SRS configuration parameter information for each element carrier wave(S1020).

Description

Method and apparatus for aperiodic reference signal transmission and reception in a communication system using a multi-component carrier {Method and Apparatus for Transmitting and Receiving Aperiodic Reference Signal in communication system with Multiple Component Carriers}

The present invention relates to a method and apparatus for aperiodic reference signal transmission and reception in a wireless communication system, in particular, a communication system using a multi-element carrier.

In particular, in transmitting an aperiodic reference signal in a communication system using a multi-component carrier, aperiodic to downlink control information (hereinafter referred to as "DCI") transmitted through a physical control channel. Component Carrier (hereinafter referred to as 'Component Carrier' or 'CC') identification information, which is a target of reference signal transmission, is included, and transmission parameter configuration information for aperiodic reference signal transmission of the CC includes separate signaling. Send it through.

As communication systems evolve, consumers, such as businesses and individuals, are demanding wireless terminals that support a variety of services.

In current mobile communication systems such as 3GPP, Long Term Evolution (LTE), and LTE-A (LTE Advanced), it is a high-speed, high-capacity communication system that can transmit and receive various data such as video and wireless data, beyond voice-oriented services. In addition, the development of technology that can transfer large amounts of data comparable to wired communication networks is required, and an appropriate error detection method is required to minimize system information loss and improve system transmission efficiency. Doing.

In addition, in various current communication systems, various reference signals have been proposed to provide information on a communication environment to the counterpart device through uplink or downlink.

For example, in an LTE system, which is one of mobile communication methods, a channel reference (channel measurement or channel estimation) indicating a channel state of a user equipment (hereinafter referred to as UE or UE) during uplink transmission. As a reference signal, a sounding reference signal (hereinafter referred to as a "SRS") is transmitted to a base station apparatus, while CRS (reference signal), which is a reference signal, is used to identify channel information during downlink transmission. A cell-specific reference signal is transmitted every subframe.

On the other hand, these reference signals (Reference Signals) are commonly generated by the transmission apparatus of the reference signal, that is, the UE in the case of the uplink reference signal, the base station apparatus in the case of the downlink reference signal periodically and transmitted to the reference signal receiving apparatus .

Recently, however, a discussion has been made to transmit a channel estimation reference signal aperiodically due to flexibility of a communication system, but a specific method thereof has not been determined.

In addition, unlike a communication system using a single carrier (carrier) consisting of one frequency band to date, in a recently discussed wireless communication system, a plurality of component carriers (hereinafter referred to as "component carrier" or "CC") Is discussed.

As described above, in case of a communication system using a plurality of CCs, each CC may function as one cell, and in a wireless communication system which is recently discussed, it is not necessary to transmit a channel estimation reference signal for each CC. However, the specific method is not determined.

In consideration of such a situation, there is a need for a specific transmission scheme of an aperiodic channel estimation reference signal in a communication system using a plurality of CCs.

An embodiment of the present invention provides a signaling method for aperiodic transmission of a reference signal in a communication system using a plurality of CCs.

An embodiment of the present invention provides an aperiodic SRS (hereinafter referred to as 'A-SRS') transmission and reception method in a communication system using a plurality of CCs.

An embodiment of the present invention provides a technique of using a predetermined field of downlink control information transmitted on a physical control channel to indicate a CC to transmit A-SRS in a communication system using a plurality of CCs.

According to an embodiment of the present invention, in a communication system using a plurality of CCs, identification information of a CC to transmit A-SRS is transmitted through a physical control channel, and A-SRS configuration parameter information is transmitted through separate signaling. To provide technology.

An embodiment of the present invention provides a technology capable of obtaining identification information of a CC to transmit A-SRS through an A-SRS configuration parameter information indicator in a communication system using a plurality of CCs.

An embodiment of the present invention is a non-periodic reference signal receiving method by an aperiodic reference signal receiving apparatus in a wireless communication system using a plurality of component carriers (CC), the identification of the component carrier to be transmitted of the aperiodic reference signal Generating and transmitting downlink control information of a physical control channel including the information; and generating using the component carrier identification information of the aperiodic reference signal and the aperiodic reference signal configuration parameter information for each component carrier signaled separately. A non-periodic reference signal receiving method comprising the step of receiving a non-periodic reference signal is transmitted.

Another embodiment of the present invention is an apparatus for receiving an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC), A-SRS transmission target CC identification information generation unit for generating A-SRS transmission target CC identification information for indicating a CC to transmit the A-SRS among a plurality of uplink CC configured in the terminal, and the generated A-SRS transmission target CC A DCI processor for generating downlink control information (DCI) including identification information, a PDCCH transmitter for transmitting the generated DCI to a UE through a physical control channel, and the UE determined as the A-SRS transmission target CC identification information Provided is an aperiodic sounding reference signal receiver including an A-SRS receiver for receiving an A-SRS transmitted through an A-SRS transmission target CC.

Another embodiment of the present invention is a method of transmitting an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC). Receiving the DCI including the A-SRS transmission target CC identification information through a physical control channel, and receiving the A-SRS configuration parameter information to be used by the A-SRS transmission target CC through higher-level signaling separate from the physical control channel. Determining an A-SRS transmission target CC to which the A-SRS is to be transmitted, based on the A-SRS transmission target CC identification information, and A-SRS configuration parameter information to be used by the A-SRS transmission target CC. And a step of generating an A-SRS using the determined A-SRS configuration parameter information and transmitting the same through the A-SRS transmission target CC.

Another embodiment of the present invention is an apparatus for transmitting an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC). A DCI receiving unit receiving a DCI including the A-SRS transmission target CC identification information as a physical control channel, an RRC processing unit receiving A-SRS configuration parameter information for each CC to be used by the A-SRS transmission target CC through RRC signaling; An A-SRS transmission target CC determining unit configured to determine an A-SRS transmission target CC to transmit the A-SRS based on the A-SRS transmission target CC identification information, and an A-SRS configuration to be used by the A-SRS transmission target CC An A-SRS configuration parameter determiner for determining parameter information, and an A-SRS transmitter for generating an A-SRS using the determined A-SRS configuration parameter information and transmitting the A-SRS through the CC to which the A-SRS is transmitted. Aperiodic Sounding Reference Signal Provide a transmitter.

Another embodiment of the present invention is a method of transmitting and receiving an aperiodic sounding reference signal (A-SRS) in a wireless communication system using a plurality of component carriers (CC). In addition, the A-SRS receiver includes the A-SRS transmission target element carrier identification information in the downlink control information (DCI) of the physical control channel and transmits it to the SRS transmitting apparatus, and the SRS transmitting apparatus is signaled separately from the physical control channel. A-SRS transmission parameter transmission and reception method, characterized in that for transmitting the A-SRS through the A-SRS transmission target component carrier using the A-SRS transmission parameter information for each CC and the A-SRS transmission target component carrier identification information To provide.

1 is a diagram schematically illustrating a wireless communication system to which an embodiment of the present invention is applied.
2 illustrates a general subframe and time slot structure of transmission data that can be applied to an embodiment of the present invention.
3 and 4 are tables showing configuration information of an SRS subframe that can be used in an embodiment of the present specification.
5 is a diagram illustrating configuration information on an SRS bandwidth.
6 and 7 illustrate examples of information that may be set in connection with SRS transmission in the present specification.
8 illustrates a component carrier structure of a multi-component carrier environment (CA environment) to which the embodiment is applied.
FIG. 9 illustrates an embodiment utilizing four states separated by two bits of DCI format 4 in a single element carrier environment.
10 is a flowchart illustrating an A-SRS receiving method according to an embodiment of the present invention.
FIG. 11 is an example of A-SRS transmission target CC identification information and an A-SRS configuration parameter set table matched when the terminal configures three CCs.
FIG. 12 illustrates an embodiment in which two CCs of a terminal are capable of A-SRS transmission simultaneously in both CCs.
FIG. 13 illustrates a data transmission state of each CC when an embodiment of the present invention is applied.
14 is a flowchart illustrating an A-SRS receiving method according to another embodiment.
15 is a functional block diagram of an A-SRS receiving apparatus according to an embodiment of the present invention.
16 is a flowchart illustrating an A-SRS transmission method according to an embodiment of the present invention.
17 is a functional block diagram of an A-SRS transmission apparatus according to an embodiment of the present invention.

Hereinafter, some embodiments of the present invention will be described in detail with reference to exemplary drawings. In adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are assigned to the same components as much as possible even though they are shown in different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

1 illustrates a wireless communication system to which embodiments of the present invention are applied.

Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, and the like.

Referring to FIG. 1, a wireless communication system includes a user equipment (UE) 10 and a base station 20 (BS).

Terminal 10 in the present specification is a generic concept that means a user terminal in wireless communication, WCDMA, UE (User Equipment) in LTE, HSPA, etc., as well as MS (MobileStation), UT (User Terminal) in GSM It should be interpreted as a concept that includes a subscriber station (SS), a wireless device, and the like.

A base station 20 or a cell generally refers to a fixed station communicating with the terminal 10 and includes a Node-B, an evolved Node-B, and a Base Transceiver. May be called other terms such as System, Access Point, Relay Node

That is, in the present specification, the base station 20 or the cell should be interpreted in a comprehensive sense indicating some areas covered by the base station controller (BSC) in the CDMA, the NodeB of the WCDMA, and the like. It is meant to cover various coverage areas such as microcell, picocell, femtocell and relay node communication range.

In the present specification, the terminal 10 and the base station 20 are two transmitting and receiving entities used to implement the technology or technical idea described in the present specification and are used in a comprehensive sense and are not limited by the terms or words specifically referred to. .

There is no limitation on the multiple access scheme applied to the wireless communication system. Various multiple access techniques such as Code Division Multiple Access (CDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiple Access (OFDMA), OFDM-FDMA, OFDM-TDMA, OFDM-CDMA Can be used.

A TDD (Time Division Duplex) scheme in which uplink and downlink transmissions are transmitted using different time periods, or an FDD (Frequency Division Duplex) scheme in which they are transmitted using different frequencies can be used. In addition, a hybrid method combining the two methods may also be used.

One embodiment of the present invention provides asynchronous wireless communication that evolves into Long Term Evolution (LTE) and LTE-advanced through GSM, WCDMA, HSPA, and synchronous wireless communication that evolves into CDMA, CDMA-2000, and UMB). Applicable to resource allocation. The present invention should not be construed as being limited or limited to a specific wireless communication field, but should be construed as including all technical fields to which the spirit of the present invention can be applied.

A wireless communication system to which an embodiment of the present invention is applied may support uplink and / or downlink HARQ, and may use a channel quality indicator (CQI) for link adaptation. In addition, multiple access schemes for downlink and uplink transmission may be different from each other. For example, downlink uses Orthogonal Frequency Division Multiple Access (OFDMA), and uplink uses Single Carrier-Frequency Division Multiple Access (SC-FDMA). ) Is the same as can be used.

The layers of the radio interface protocol between the terminal and the network are based on the lower three layers of the Open System Interconnection (OSI) model, which are well known in communication systems. The physical layer may be divided into a second layer (L2) and a third layer (L3), and the physical layer belonging to the first layer provides an information transfer service using a physical channel.

Meanwhile, in an example of a wireless communication system to which an embodiment of the present invention is applied, one radioframe or a radio frame is composed of 10 subframes, and one subframe is two slots. ) May be included.

The basic unit of data transmission is a subframe unit, and downlink or uplink scheduling is performed on a subframe basis. One slot may include a plurality of OFDM symbols in the region of the time axis and a plurality of subcarriers (or subcarriers) in the region of the frequency axis.

For example, a subframe consists of two time slots, and each time slot has seven symbols (Extended CP (cyclic extended) when using a normal cyclic prefix (CP) in the time domain. prefix)) and 180kHz bandwidth in the frequency domain (in general, one subcarrier has a bandwidth of 15kHz, so 180kHz bandwidth corresponds to a total of 12 subcarriers). It may include corresponding subcarriers. The time-frequency domain defined by one slot on the time axis and a bandwidth of 180 kHz on the frequency axis may be referred to as a resource block or a resource block (RB), but is not limited thereto.

2A illustrates a general subframe and time slot structure of transmission data that can be applied to an embodiment of the present invention.

Referring to FIG. 2A, the transmission time of a frame is divided into TTIs (transmission time intervals) of 1.0 ms duration. The terms TTI and sub-frame may be used in the same meaning, and the frame is 10 ms long and includes 10 TTIs.

2b illustrates a general structure of a time-slot according to an embodiment of the present invention.

Referring to FIG. 2B, a TTI is a basic transmission unit, where one TTI includes two time slots 202 of equal length, each time slot having a duration of 0.5 ms. The time-slot includes a plurality of long block LBs 203 corresponding to each symbol. The LBs are separated into cyclic prefix CPs 204. In this case, the cyclic prefix includes a normal cyclic prefix and an extended cyclic prefix according to the length thereof. In the case of using a normal cyclic prefix, the plurality of LBs is one. Seven are included in the time-slot of. When the extended cyclic prefix (Extended CP) is used, the plurality of LBs includes six or three in one time-slot.

Taken together, one TTI or subframe may contain 14 LB symbols when using normal cyclic prefixes, and typically 12 LBs when using extended cyclic prefixes. Symbol or special case may include six LB symbols, but the present specification is not limited to such a frame, subframe or time-slot structure.

FIG. 2C illustrates a configuration of one resource block (RB) 230 during one subframe or TTI 201 according to an embodiment of the present invention, wherein each TTI or subframe has a normal cyclic prefix in the time domain. In the case of CP, 14 symbols (axis) or extended cyclic prefix (Extended CP) is divided into 12 (or 6) symbols (axis) 203. Each symbol (axis) may carry one OFDM symbol.

In addition, the total system bandwidth of 20 MHz is divided or divided into subcarriers 205 having different frequencies. For example, as mentioned above, it consists of one slot in the time domain and subcarriers corresponding to a bandwidth of 180 kHz in the frequency domain (typically 12 subcarriers with a bandwidth of 15 kHz per subcarrier). An area may be called a resource block or a resource block (RB).

For example, a bandwidth of 10 MHz within 1 TTI may include 50 RBs in the frequency domain.

Each grid space constituting the resource block RB may be referred to as a resource element (hereinafter, referred to as a RE).

For example, in a resource region corresponding to a bandwidth of 180 kHZ in an area of the time axis and in an area of the frequency axis, when a normal cyclic prefix (Normal CP) is used and the frequency bandwidth per subcarrier is 15 kHz, A total of 14 (symbols) × 12 (subcarriers) = 168 REs may exist in each resource region of the above structure.

Meanwhile, as one of the current wireless communication schemes, as a reference signal transmitted from a terminal to a base station in LTE (Long Term Evolution) and LTE-Advanced communication systems, a demodulation reference signal (DMRS) and a sounding reference signal are used. (Sounding Reference Signal; hereinafter referred to as 'SRS' or 'sounding reference signal' or 'sounding reference signal') is defined.

In more detail, three reference signals (RS, or reference signals) are defined in downlink, a cell-specific reference signal (CRS), and an MBSFN reference signal (Multicast / Broadcast over). Single Frequency Network Reference Signal (MBSFN-RS) and UE-specific Reference Signal (UE-specific Reference Signal).

That is, in a wireless communication system, a terminal transmits a reference signal for uplink channel estimation or measurement, which is a type of reference signal, to a single base station in order to deliver uplink channel information to the base station. An example of the channel estimation reference signal may be a sounding reference signal (SRS) used in LTE and LTE-Advanced, which has a function such as a pilot channel for an uplink channel.

In the following specification, a process and method of controlling aperiodic transmission of a reference signal will be described. The reference signal means a signal transmitted between the terminal and the base station. An embodiment of the reference signal will be described with reference to a channel estimation reference signal and a sounding reference signal (SRS), which is an embodiment thereof. However, the present invention is not limited to an SRS or a reference signal for channel estimation or channel measurement. It should be understood as a concept including all kinds of reference signals used in a link or a downlink.

3 and 4 are tables showing configuration information of an SRS subframe that can be used by one embodiment of the present specification.

The transmission subframe of the periodic sounding reference signal (Periodic SRS) is determined by the parameter srs-SubframeConfig as shown in 310 of FIG. 3. The srs-SubframeConfig (4-bit) 310 is transmitted in a higher layer as a cell-specific parameter and SRS transmission is possible in the last symbol of a subframe satisfying Equation 1.

[Equation 1]

는 오프셋(offset)이며, 이들은 셀 특이적 파라미터로 정해지거나 srs-SubframeConfig에 따라 미리 정해진 값들일 수 있다. 상기 값을 만족시키는n_s의 마지막 심볼에 SRS 전송이 가능하다. n_s는 슬롯의 인덱스이다.In Equation 1, T _SFC is a subframe configuration period.

Is an offset, and these may be determined as cell specific parameters or may be predetermined values according to srs-SubframeConfig. SRS transmission is possible on the last symbol of n _s that satisfies the above value. n _s is the index of the slot.

3 is a subframe configuration table of the FDD sounding reference signal defined in LTE. Each format (srsSubframeConfiguration) is defined as 4 bits, and in each case, a transmission period and an offset of an actual transmission subframe are defined.

는 {2, 3}). 이 경우, 상기 SRS는 각 서브프레임의 가장 마지막 심볼에 송신될 수 있다. 예를 들어, 하나의 서브프레임이 14개의 심볼들(Normal Cyclic Prefix인 경우)로 구성될 경우, 14번째 심볼에서 SRS를 송신하며, 12개의 심볼들(Extended Cyclic Prefix인 경우)로 구성될 경우, 12번째 심볼에서 SRS를 송신한다. 물론, 본 명세서에서 SRS가 송신되는 심볼의 위치가 이에 한정되는 것은 아니다. That is, when the srsSubframeConfiguration value is 8 (1000 in binary), for example, SRS is transmitted in the second and third subframes every 5 subframes (T _SFC is 5,

Is {2, 3}). In this case, the SRS may be transmitted in the last symbol of each subframe. For example, when one subframe consists of 14 symbols (in the case of Normal Cyclic Prefix), when the SRS is transmitted in the 14th symbol, and consists of 12 symbols (in the case of Extended Cyclic Prefix), SRS is transmitted in the 12th symbol. Of course, the position of the symbol in which the SRS is transmitted herein is not limited thereto.

By the SRS setting, the SRS may be transmitted periodically in each radio frame or transmission period for each cell (base station).

Meanwhile, the base station informs each terminal of the transmission period and offset of the SRS through the SRS configuration index (10-bit) 410 of FIG. 4, which is a UE-specific parameter. The transmission period is one of {2,5,10,20,40,80,160,320}, and the offset has the number of branches equal to the size of the transmission period for each transmission period. For example, when I _SRS = 20, the transmission period is 20ms, and the offset is 3ms, which is the value of I _SRS minus 17.

도 5는 SRS 대역폭에 대한 설정 정보를 보여주는 도면이다. SRS 대역폭 설정(SRS bandwidth configuration(3-bit), 510)과 SRS 대역폭(SRS bandwidth(2-bit), 520)를 나타낸다. SRS 대역폭 설정(C_SRS)은 셀 특이적 파라미터(cell-specific parameter)로서 셀 내의 모든 단말에게 같은 값이 전송된다. 반면 SRS 대역폭 B_SRS)는 UE 특이적 파라미터(UE-specific parameter)로서 각 단말에 서로 다른 값의 할당이 가능하다. 셀 내의 단말들은 C_SRS 에 의해 결정되는 4가지 SRS 대역폭(bandwidth) 중 하나가 선택되며, UE 특이적 파라미터인 B_SRS를 통해 단말이 전송할 SRS 대역폭의 크기가 결정된다. C_SRS, B_SRS 는 상위계층에서 전달되는 파라미터이며 그 값은 시스템 대역폭(system bandwidth)에 따라 다르다. 도 5는 시스템 대역폭을 나타내는 RB(resource block)의 범위가 40<RB(resource block)

60 인 경우의 예를 표시한 것으로 도 5에 의하면, C_SRS = 2, B_SRS = 2이면 단말은

의 값을 갖는다. 이는 SRS 전송 대역폭(

)이 4RB를 의미하며 N₂는 다음 SRS 전송을 위한 값으로 사용된다. 다시 설명하면, C_SRS값과 B_SRS값을 이용하여 SRS를 송신할 수 있는 주파수의 범위와, 해당 주파수의 범위(

)가 어느 지점에서 시작할 수 있는지에 대한 정보(N₂)를 설정할 수 있다. 즉, C_SRS = 2, B_SRS = 2이면 전체 4개의 RB(

= 4)에 대해 SRS를 송신하는 것을 의미한다.

5 is a diagram illustrating configuration information on an SRS bandwidth. SRS bandwidth configuration (SRS bandwidth configuration (3-bit), 510) and SRS bandwidth (SRS bandwidth (2-bit), 520). The SRS bandwidth setting (C _SRS ) is a cell-specific parameter and the same value is transmitted to all terminals in the cell. On the other hand, SRS bandwidth B _SRS ) is a UE-specific parameter that can be assigned a different value to each terminal. One of four SRS bandwidths determined by the C _SRSs is selected for the UEs in the cell, and the size of the SRS bandwidth that the UE transmits is determined through the UE-specific parameter B _SRS . C _SRS and B _SRS are parameters transmitted from a higher layer and their values depend on system bandwidth. 5 shows that a resource block (RB) indicating a system bandwidth has a range of 40 <RB (resource block).

In the example of 60, FIG. 5 shows that when C _SRS = 2 and B _SRS = 2, the UE

Has the value of. This is the SRS transmission bandwidth (

) Means 4RB and N ₂ is used as a value for the next SRS transmission. In other words, using the C _SRS value and the B _SRS value, the range of frequencies at which the SRS can be transmitted and the range of the corresponding frequencies (

Information N ₂ at which point can be started. That is, if C _SRS = 2 and B _SRS = 2, all four RBs (

= 4) means transmitting the SRS.

6 and 7 illustrate examples of information that may be set in connection with SRS transmission in the present specification. Comb (comb) means that is configured to transmit by dividing the frequency bandwidth in transmitting the SRS. The Comb parameter in FIG. 6 means information indicating that the SRS can be transmitted in the even or odd subcarriers in the SRS transmission. For example, Comb0 may refer to an even subcarrier and Comb1 may refer to an odd subcarrier. By using the Comb parameter, two terminals pointing to the same SRS resource on the frequency can be distinguished through a frequency position and an SRS bandwidth.

In FIG. 7, a total of eight cyclic shifts are illustrated. 3 bits of information may be transmitted to indicate a cyclic shift.

In order to transmit the SRS, it is necessary to set various information, that is, an area of a resource to which the SRS is to be transmitted, time information to transmit the SRS, and the like. In addition, in order to transmit an aperiodic SRS (hereinafter referred to as 'A-SRS'), information about such resources and time needs to be set. In addition, since aperiodic SRS (A-SRS) may need to check fast sounding at any particular point in time, faster information transmission and reception through a physical channel may be required than transmitting and receiving information in terms of RRC (Radio Resource Control). have.

Meanwhile, in the physical channel, transmission and reception of information related to uplink and information related to downlink may exist. In an embodiment of the present specification, it will be described to include A-SRS-related information in one or two bits due to a limitation of information that can be carried in a physical channel. Of course, the present invention can be applied to a larger range of information (3 bits or more) in addition to 1 to 2 bits in applying an embodiment of the present specification. However, each embodiment of the present invention will be described based on the minimum usable bit size.

An embodiment of a physical channel to include the 1 to 2 bits will be described based on DCI format 0 or DCI format 4.

DCI format 0 and DCI format 4 may be used as a transmission format of a physical control channel to include A-SRS transmission information.

For example, in DCI format 0, a new 1-bit for triggering A-SRS transmission may be added, thereby instructing transmission of A-SRS to be initiated, and A-SRS for specific A-SRS transmission. The transmission parameters may be transmitted in a separate higher-end signaling (eg, RRC) signal.

In addition, 2-bit may be added in DCI format 4 to indicate A-SRS transmission information, and one of these states (1-state) indicates no A-SRS Activation. It can be used for the purpose of transmitting the information about the A-SRS transmission parameter using the remaining three states (3-state).

Meanwhile, one of the communication systems currently used uses one carrier having a constant frequency bandwidth (up to 20 MHz). In such a wireless communication system, an SRS and an A-SRS for one component carrier (CC) are used. The terminal is transmitting to the base station in the manner described above.

However, in the new communication system being discussed recently, a discussion is being made to expand the bandwidth in order to satisfy the required performance, and in order to expand the bandwidth, a unit carrier that the communication terminal can have in advance is component carrier (Component Carrier). ) And using up to five of these component carriers is being discussed.

8 illustrates a component carrier structure of a multi-component carrier environment (CA environment) to which the embodiment is applied.

As shown in FIG. 8, in a CA environment, a plurality of conventional 20 MHz component carriers (eg, CC1 to CC4 represented by 110 to 140 of FIG. 8) may be bundled and used. For example, five component carriers may be bundled together. A technology that can be extended to have a bandwidth of up to 100 MHz, and a technique in which a plurality of component carriers can be bundled and used is called carrier aggregation technology. Frequency bands that can be allocated as component carriers may be continuous or discontinuous.

In relation to carrier aggregation technology (also referred to as carrier aggregation (CA)), a number of component carriers are backwards compatible carriers, non-backwards compatibility carriers, and extension carriers depending on characteristics. It can be divided into three types.

A compatible carrier (referred to as "backwards compatible carrier" or "BC" or "BC") is a carrier that can be applied to all existing versions of LTE, and may operate as a single (single) carrier or a carrier aggregation. It can also act as part of). In time division duplex (TDD), the bandwidth and location of uplink and downlink should always be the same. In addition, in FDD (Frequency Division Duplex), uplink and downlink should always have cell-specific connection settings and may exist in pairs.

On the other hand, incompatible carriers (hereinafter referred to as "non-backwards compatibility carrier" or "non-compatible carriers" or "NBC") are not accessible to the UE by the communication system so far, and operate as a single (alone) if generated from a duplex distance. It is possible to do this, otherwise it is a carrier that operates only as part of a carrier aggregation.

In addition, an extension carrier (hereinafter referred to as an "extension carrier" or "ExC") may be operated as a part of at least one component carrier set including a carrier that cannot be operated singly (single) and can be used alone. Only used, it is a carrier used only for bandwidth expansion.

In this multi-component carrier environment, one CC is a primary CC (hereinafter referred to as 'PCC' or 'PC' or 'RC' which is initially connected to the UE (Connection or RRC Connection) among various CCs. Major carrier).

Preferably, the PCC is responsible for a connection or RRC connection management function that manages a plurality of CCs provided by the UE and the BS and is responsible for signaling, and is connection information associated with the UE. Although it is used as a special element carrier that manages UE context and manages security key values for security setting between the terminal and the base station, it is not limited to these terms or functions.

In addition, such a major carrier (PCC) is connected to the terminal is always in the activation (Activation) state in the RRC connection mode (RRC Connection Mode).

In the above description, CCs allocated to UEs in addition to PCCs, which are initially connected with UEs (Connection or RRC Connection), among CCs, are also referred to as secondary CCs (hereinafter referred to as secondary CCs). SCC). Preferably, the subcarrier carrier (SCC) is an extended carrier (carrier) for the additional resource allocation, such as the terminal in addition to the main carrier (PCC) may be divided into an activation (Activation) or deactivation (Deactivation) state.

In the present specification, "SCC" is used as a comprehensive concept including all component carriers except PCC among multi-component carriers, and after the terminal configures some of the SCCs, activates them, and then data through them. It becomes the state which can transmit and receive.

The activation state refers to a state in which downlink control information and downlink data information can be received. In addition, channel quality information (CQI) can be measured. On the other hand, the inactive state refers to a state in which downlink control information and downlink data information cannot be received. In addition, channel quality information (CQI) cannot be measured.

In addition, each SCC is downlink (hereinafter referred to as "DL" or "downlink" or "downlink") or uplink (hereinafter referred to as "UL" or "uplink" or "uplink"). It may be assigned and used separately for each.

In a multi-element carrier environment, when the terminal is connected to the base station, the PCC is connected to the RRC like a conventional single-element carrier and thus instructs periodic transmission of the SRS in the manner described above, and the terminal periodically sends the SRS accordingly. Can be transmitted to the base station.

However, in such a multi-component carrier (CA) environment, there is no situation in which aperiodic SRS transmission is not defined for various CCs such as PCC and other SCCs.

Meanwhile, in a communication system using one component carrier, the A-SRS transmission mechanism may be implemented as follows according to DCI format 0 definition or DCI format 4 usage.

1) Method using DCI format 0

In DCI format0, new 1-bit information may be added for triggering A-SRS transmission, and thus, instructing the UE to start A-SRS transmission on a corresponding CC. On the other hand, parameters for A-SRS transmission (SRS configuration parameters) are delivered to the terminal by higher-end signaling such as RRC. That is, parameters such as SrsBandwidth, FrequencyDomainposition, transmissionComb, and cyclic shift for A-SRS transmission are composed of one set, which is transmitted to the terminal through RRC signaling.

When the A-SRS transmission triggering bit of DCI format 0 becomes 1 (may be 0 according to definition), the UE allocates the last symbol A-SRS of the corresponding subframe, but includes frequency bandwidth, start position, comb, and cyclic The shift and the like may be determined according to a separate RRC transmitted A-SRS configuration parameter set. The time-frequency resource region to which the A-SRS is allocated is modulated into an OFDM signal and transmitted to the base station. The received base station estimates the channel state information of the corresponding channel using the A-SRS and can be used for later scheduling. .

2) Method using DCI format 4

Unlike DCI format 0, DCI format 4 can be defined to use two bits of information for A-SRS triggering or configuration, thus using the four states in total State can be expressed.

One of the four states (for example, the state expressed as '00') is used to indicate "No A-SRS activation" that does not transmit A-SRS, and indicates the remaining three states. A-SRS transmission can be indicated.

That is, DCI format 4 may be added with two new bits related to A-SRS transmission, one of which is used to indicate that no A-SRS is transmitted, and 3 using three other states. Discussing different kinds of A-SRS configuration parameter sets is discussed, and FIG. 9 shows an example of such a scheme.

FIG. 9 illustrates an embodiment utilizing four states separated by two bits of DCI format 4 in a single element carrier environment.

As shown in FIG. 9, state 4 represents No A-SRS Activation among the four states indicated by the 2 bits related to A-SRS transmission of DCI format 4, and the remaining states 1 to 3 are respectively. It is defined to correspond to the first A-SRS configuration parameter set 910 to the third A-SRS configuration parameter set 930 which are three types of A-SRS configuration parameter sets.

For reference, in FIG. 9, matching of 2 bits related to A-SRS transmission of DCI format 4 and its state is merely exemplary.

The UE receives and stores the A-SRS configuration parameter set information or the A-SRS configuration parameter set table as semi-static in RRC as shown in FIG. 9, and the A-SRS of DCI format 4 transmitted by the base station. After checking two bits related to transmission, one of the four A-SRS configuration parameter sets among the four states is selected to transmit the A-SRS.

For example, if 2 bits related to A-SRS transmission of DCI format 4 transmitted by the base station is '01', the UE recognizes that it is in state 1, and thus is defined in the second A-SRS configuration parameter set 920 corresponding thereto. The A-SRS is transmitted based on the various parameters.

Using this scheme, the base station can dynamically use one of three types of A-SRS configuration parameter sets for a specific terminal, thereby obtaining A-SRS transmission gains.

However, this scheme using DCI format 4 reduces the number of branches for A-SRS allocation in a communication system using a single component carrier as described above. There may be some doubt as to how much it would benefit to use only one set of A-SRS configuration parameters and three sets in DCI format 4.

In addition, the above embodiments are all limited to the case of using a single CC, and when using a plurality of CCs in a CA environment, the definition of A-SRS transmission should be considered.

The present invention is proposed by such a request, and is a method for transmitting and receiving A-SRS in a communication system using a plurality of CCs, and the downlink control information of a physical control channel (for example, a base station) in an SRS receiver A-SRS transmission target component carrier identification information is included in DCI) and transmitted to an SRS transmitting apparatus (for example, a terminal, etc.), and the SRS transmitting apparatus separately transmits A-SRS transmission parameter information for each component carrier and the A-SRS signaled separately. The A-SRS is transmitted through the A-SRS transmission target component carrier using the SRS transmission component CC identification information.

The A-SRS transmission element CC identification information may be represented by one or more of four states represented by 2 bits, and the downlink control information may be DCI format 4, but is not limited thereto.

The 'A-SRS transmission element CC identification information' is not limited to its English language or expression, and means information of two or more bits additionally defined in DCI format 4 to indicate A-SRS transmission. It should be understood as comprehensive and may be interpreted as being distinct from a Carrier Indicator Field (CIF) which is already defined to distinguish component carriers in the PDCCH.

The A-SRS transmission parameter information may be included in an A-SRS transmission parameter set table including an A-SRS configuration parameter set allocated to each CC, but is not limited thereto.

Also, the A-SRS transmission parameter information, the A-SRS configuration parameter set, or the A-SRS transmission parameter set table may be transmitted to the SRS transmitter through higher level signaling. However, signaling may be RRC, but is not limited thereto.

The A-SRS configuration parameter set for each component carrier includes SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), transmissionComb (transmission comb information), cyclic shift (cyclic shift information), number of antenna Ports (antenna port number information) information is included and may include, but is not limited to, SrsHoppoingBandwidth (hopping bandwidth information), duration (duration information), etc. according to SRS hopping.

In addition, the component carrier for transmitting the DCI is a primary component carrier (PCC) or a secondary component carrier (SCC), and the A-SRS transmission target component carrier indicated by the A-SRS transmission target component carrier identification information is the primary CCI is transmitted It may be a separate uplink component carrier (UL CC) rather than the component carrier or the secondary component carrier.

That is, in one embodiment of the present invention, unlike DCI format 0, DCI format 4 may be defined to use 2-bit information for A-SRS triggering or configuration, and thus, a total of four states may be defined. It is possible to express the transmission state (State) of the A-SRS, and one of four states (for example, a state represented by '11') indicates that no A-SRS is transmitted. It is used to indicate "activation", and the remaining three states can be used to designate an A-SRS transmission target CC to transmit A-SRS. Of course, the A-SRS configuration parameter information to be used by each A-SRS transmission target CC may be transmitted to the terminal through separate signaling (for example, RRC signaling of L3).

Hereinafter, an embodiment of a reference signal to which the present invention can be applied will be described with reference to SRS, but is not limited thereto. As well as other uplink reference signals such as DM-RS, all the technical concepts of the present invention may be applied. It should be understood as a concept including a reference signal.

10 is a flowchart illustrating an A-SRS receiving method according to an embodiment of the present invention.

The A-SRS reception method according to the present embodiment is generally performed by an SRS receiver such as an eNB, but is not limited thereto. In the case of a downlink reference signal, the A-SRS reception method may be performed by a UE. .

First, the SRS receiving apparatus generates downlink control information of a physical control channel including A-SRS transmission target component carrier identification information and transmits the generated downlink control information to the SRS transmitting apparatus (S1010), and the SRS transmitting apparatus generates the A-SRS. And receiving the A-SRS transmitted through the A-SRS transmission target component carrier using the transmission target component carrier identification information and the separately signaled A-SRS configuration parameter information for each component carrier (S1020). have.

Further, optionally, the method may further include transmitting the A-SRS configuration parameter information (set table) for each CC to the A-SRS transmitting apparatus through RRC, which is a separate signaling (S1005).

The physical control channel is a physical downlink control channel (PDCCH), the downlink control information may be DCI format 4, and the A-SRS transmission element CC identification information may be represented by 2 bits. Hereinafter, the configuration will be described as an example, but is not limited thereto. Any other channel, information, number of bits, etc. may be used.

The field defined in DCI format 4 used in this embodiment consists of a total of A bits (a ₀ to a _A-1 ) including zero padding bits, of which two bits are A-SRS transmissions according to the present embodiment. Can be used as the target CC identification information.

Meanwhile, DCI format 4 used in the present embodiment is used for scheduling PUSCH in one uplink cell having a multi-antenna port transmission mode, and has a carrier indicator field (CIF) of 0 or 3 bits. Resource block allocation and hopping resource allocation bits, TPC indication bits of scheduled PUSCH, cyclic shift and OCC index fields (3 bits) for DM-RS, 2 bits of UL index, downlink allocation index (DAI) 2 bits, CQI request 1 or 2 bits, multi-cluster flag 1 bit, etc. may be included, but is not limited thereto.

Of course, DCI format 4 used in the present embodiment may further include a 2-bit field as 'A-SRS transmission target CC identification information' as described above, and 'A-SRS transmission target CC identification information' It is not limited to the terms or expressions, and may be expressed differently in other expressions such as an SRS Request or an A-SRS Request.

In addition, the A-SRS transmission target CC identification information used in this embodiment is all forms defined in the DCI to identify the CC to transmit the A-SRS or to indicate the A-SRS configuration of the CC in accordance with the spirit of the present invention The state indicating R-configured A-SRS Parameter Set, which is currently under discussion, should be interpreted as including the information or field of the A-SRS transmission target CC according to this embodiment. It can also be used as information.

FIG. 11 is an example of A-SRS transmission target CC identification information and an A-SRS configuration parameter set table matched when the terminal configures three CCs.

FIG. 11 illustrates a case in which a terminal to perform A-SRS transmission is configured with three CCs CC1 and CC3 among five CCs CC0 to CC4, among which CC1 functions as a PCC which is a primary component carrier.

Referring to FIG. 10 and FIG. 11, the base station 2 bit information for specifying a CC to be A-SRS transmission target among the fields of DCI format 4 included in the PDCCH of the CC1 CC1 that is connected to the RRC Create and send to the terminal.

In addition, the terminal receives and stores the CC-specific A-SRS configuration parameter set table shown in FIG. 11 through higher-level signaling such as separate RRC signaling.

Upon receiving the information of the DCI format 4 including the 2-bit A-SRS transmission target CC identification information, the UE checks which CC among the currently configured CCs to transmit the A-SRS from the identification information, and transmits separately. The A-SRS configuration parameter set of the corresponding A-SRS transmission target CC is determined from the CC-specific A-SRS configuration parameter set table shown in FIG.

Subsequently, the terminal may include various parameters included in the corresponding A-SRS configuration parameter set (SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), transmissionComb (transmission comb information), cyclic shift (cyclic shift information), and number of According to antenna ports (antenna port number information) SrsHoppoingBandwidth (hopping bandwidth information), duration (duration information, etc.), A-SRS is allocated to a corresponding time-frequency resource space and transmitted to a base station.

For example, when the base station transmits the A-SRS transmission target CC identification information of '01' to the terminal in the DCI format 4 included in the PDCCH of the PC1 CCC in FIG. 11, the terminal is signaled in advance in FIG. 11. By referring to the CC-specific A-SRS configuration parameter set table as follows, it is confirmed that '01', which is the corresponding CC identification information of the A-SRS transmission target, is CC2, and according to various parameters of the A-SRS configuration parameter set corresponding to CC2, The SRS is generated and transmitted to the base station.

In this case, among the parameters included in the A-SRS configuration parameter set, SrsBandwidth (bandwidth information) and FrequencyDomainposition (band position information) are information indicating a frequency bandwidth to transmit the A-SRS and a start position in frequency space. It may be defined in a manner similar to that defined in 5, but is not limited thereto.

In addition, transmissionComb (transmission comb information) may be information that selectively indicates to transmit the SRS in the even or odd subcarriers in the A-SRS transmission, for example, Comb0 is the even subcarrier, Comb1 is It may refer to an odd subcarrier. By using the transmissionComb parameter, two terminals pointing to the same SRS resource on a frequency can be distinguished through a frequency position and an A-SRS bandwidth.

Cyclic shift information may represent three bits of information for representing a total of eight states separated by 45 degree intervals in a complex space.

FIG. 12 illustrates an embodiment in which two CCs of a terminal are capable of A-SRS transmission simultaneously in both CCs.

In FIG. 12, a terminal is configured with two CCs CC1 and CC2 among five CCs CC0 to CC4, and among them, CC1 functions as a PCC which is a primary component carrier.

In the embodiment of FIG. 12, unlike in the case of FIG. 11, one of three states (one state is used for No A-SRS Activation identification) that can be identified by two bits of A-SRS transmission object identification information is CC1 and CC2. It can be used to instruct to transmit A-SRS in all.

That is, in the case of state 3 represented by '10' among three states, A-SRS transmission target CC identification information may be configured to transmit A-SRS in both CC1 and CC2. In this case, A-SRS configuration of FIG. The parameter set table also matches the A-SRS configuration parameter set 1230 used when transmitting A-SRS in both CC1 and CC2.

Other detailed operations and definitions of A-SRS configuration parameters are the same as those of FIG. 11, and thus detailed descriptions thereof will be omitted to avoid duplication.

FIG. 13 illustrates a data transmission state of each CC when an embodiment of the present invention is applied.

In particular, FIG. 13 illustrates a case in which the above-described cross carrier scheduling is applied. In addition to control information indicating data transmission in UL CC1 using PDCCH of downlink CC1 which is a PCC, A-C through CC2 which is SCC is shown. SRS transmission can be indicated.

That is, in the nth subframe of FIG. 13, DCI format 4 information including 'A-SRS transmission target CC identification information 2 bits' indicating the A-SRS transmission of CC2 is allocated to the PDCCH of DL CC1 (PCC). Send to the terminal. The PDCCH includes control information for transmitting predetermined data through CC1 in the n + 4th subframe.

In this case, among control information in the PDCCH, control information for transmitting predetermined data through CC1 in the n + 4th subframe may be allocated to a carrier indicator field (CIF), and the CIF may represent five or more CCs. 3 bits of information.

Of course, the two bits of the 'A-SRS transmission target CC identification information' defined in the embodiment of the present invention may be understood as a concept distinct from the above-described CIF.

That is, 'A-SRS transmission target CC identification information' may be interpreted to mean two or more bits of information additionally defined in DCI format 4 to indicate A-SRS transmission in addition to the existing CIF, but is not limited thereto. no.

The UE receiving the PDCCH through the CCC CC1 confirms that the A-SRS should be transmitted in the n + 5th subframe through the UL CC2 SCC by checking the CC identification information of the A-SRS transmission.

In addition, the terminal generates an A-SRS according to the A-SRS configuration parameter set of the corresponding CC2 with reference to the A-SRS configuration parameter set table as shown in FIG. 11 or 12 received through separate RRC signaling and transmits it to the base station. Done.

In addition, since such PDCCH includes control information for transmitting predetermined data through CC1 which is PCC in the n + 4th subframe, UL CC1 is included in the n + 4th subframe as shown in FIG. Predetermined data is transmitted through the PUSCH.

Meanwhile, n ', which is a subframe in which UL CC2 transmits A-SRS, may be determined as the next subframe after the subframe in which CC1 transmits a PUSCH, but is not limited thereto.

In addition, according to the current standard content, since the A-SRS should be allocated to the last symbol of the corresponding subframe, it is expressed as shown in FIG. 13 but is not limited thereto.

Referring back to FIG. 13, FIG. 13 illustrates an example in which uplink allocation and A-SRS transmission occur in different UL CCs through DCI format 4, and independently uplink allocation and A-SRS allocation are performed. Can be directed.

That is, when uplink allocation is required for UL CC1 and A-SRS transmission is required for UL CC2, the base station uplinks through UL CC1 and DL CC linked with UL CC1 to instruct the UE to allocate uplink for UL CC1. DCI format 4 indicating allocation is transmitted, and the DCI format 4 transmitted at this time includes information for A-SRS transmission in UL CC2 (that is, 2-bit A-SRS transmission target CC identification information for indicating CC2). Will be loaded.

Then, as shown in FIG. 13, when the A-SRS transmission time point is n, the PDCCH transmission subframe indicating A-SRS triggering is n '> = n + among the A-SRS subframes of the corresponding CC (ie, CC2). A-SRS is transmitted in the first subframe satisfying 4.

14 is a flowchart illustrating an A-SRS receiving method according to another embodiment.

In the embodiment of FIG. 14, the A-SRS receiving apparatus (for example, the base station) checks the state of the terminal and selectively transmits A-SRS configuration parameter information and DCI format according to whether a single CC or a plurality of CCs are configured. Include configurations that adopt configurations.

First, the base station eNB checks the state of the terminal (S1410). Checking the state of the terminal may specifically refer to checking the number of CCs configured or activated in the corresponding terminal, but is not limited thereto. May be checked at the same time.

The information checked by the base station in step S1410 may include an activated UL CC of the terminal, a data buffer state of the terminal, a channel estimation state for each CC of the terminal, but is not limited thereto.

Next, it is determined whether the number of CCs configured or activated in the corresponding UE is a single CC or multiple CCs (S1420).

When it is confirmed that a single CC is configured or activated, the base station generates an A-SRS configuration parameter set for the single CC and transmits it to the UE through RRC (S1430), and instructs the transmission of A-SRS of a single CC (Triggering). The DCI format information (or PDCCH including the same) is generated to include 1 or 2 bits of information and transmitted to the UE as a PDCCH of the physical layer (S1440).

In this case, the DCI format including information indicating A-SRS transmission of a single CC may be DCI format 0 including 1 bit of identification information or DCI format 4 having 2 bits of identification information.

In addition, when DCI format 4 is used, as described with reference to FIG. 9, two or more (up to three) A-SRS configuration parameter sets of a single CC are generated and transmitted to the terminal in table form, which is represented by 2 bits. Three of the four states may be used to selectively specify one of a plurality of A-SRS configuration parameter sets.

On the other hand, in step S1420, when it is determined that there are a plurality of UL CCs configured or activated in the terminal, the base station as shown in Figure 11 or 12, A-SRS configuration parameter information for each of a plurality of CCs to transmit the A-SRS (I.e., generate a CC-specific A-SRS configuration parameter set table, etc.) and transmit the RRC to the UE (S1450).

In addition, the base station determines the CC (s) to transmit the A-SRS from among a plurality of CCs, as described in the embodiment below in Figure 10, and then generates the A-SRS transmission target CC identification information that can identify it with 2 bits After including the information in the DCI format 4, the DCI format 4 information is transmitted to the terminal (S1460).

Of course, FIG. 15 illustrates that the DCI information transmission steps S1440 and S1460 are performed after the A-SRS configuration parameter information transmission steps S1430 and S1450 of the CC in the case of both a single CC and a plurality of CCs. However, the present invention is not limited thereto, and the order may be changed or performed simultaneously.

Next, the base station receives the A-SRS signal transmitted through the corresponding CC (s) (S1470).

Referring to step S1470 in more detail, in the case of a single CC, the UE is instructed to perform A-SRS transmission on the CC (that is, PCC) according to the A-SRS triggering information (1 bit or 2 bits). After checking, after confirming the A-SRS configuration parameter set of the CC transmitted by the RRC, the A-SRS is generated and transmitted accordingly to the base station, and the base station receives the transmitted A-SRS.

In addition, in the case of multiple CCs, the terminal recognizes the 2-bit A-SRS transmission target CC identification information included in the DCI format 4 information, and the CC selected by using a separate RRC-specific CC-specific A-SRS configuration parameter set table Check the A-SRS configuration parameters. If the A-SRS is generated through the corresponding A-SRS configuration parameter and then transmitted to the base station through the corresponding CC, the base station receives the A-SRS.

Of course, even in this case, as described in FIG. 10, the A-SRS configuration parameter set for each component carrier may include SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), transmissionComb (transmission comb information), and cyclic. The information includes shift (cyclic shift information), number of antenna ports (antenna port number information), and may include SrsHoppoingBandwidth (hopping bandwidth information), duration (duration information), etc. according to whether or not SRS hopping is performed.

In addition, in FIG. 14, when a plurality of CCs are configured or activated, the component carrier for transmitting DCI is a primary component carrier (PCC) or a secondary component carrier (SCC), and the A-SRS transmission target component carrier identification information indicated by The A-SRS transmission target component carrier may be a separate uplink component carrier (ULCC) rather than the primary component carrier or the secondary component carrier on which the DCI is transmitted.

15 is a functional block diagram of an A-SRS receiving apparatus according to an embodiment of the present invention.

A-SRS receiving apparatus 1500 according to an embodiment A-SRS transmission target CC identification information for generating A-SRS transmission target CC identification information for indicating a CC to transmit the A-SRS among a plurality of CC configured in the terminal The DCI processing unit 1520 for generating a DCI including the generation unit 1510, the generated A-SRS transmission target CC identification information (for example, 2 bits), and transmitting the generated DCI to the UE through a physical control channel. The PDCCH transmitter 1530 includes an A-SRS receiver 1540 for receiving an A-SRS transmitted through the A-SRS target CC determined by the terminal as the A-SRS target CC identification information.

In addition, the A-SRS receiving apparatus 1500 according to an embodiment generates separate signaling (for example, by generating CC-specific A-SRS configuration parameter information for use when a plurality of CCs configured in the terminal transmit the A-SRS). CC-specific A-SRS configuration parameter information processing unit 1550 to be transmitted to the terminal via RRC signaling, etc. may optionally be included.

The A-SRS transmission target CC identification information generation unit 1510 is a 2-bit A-SRS transmission target CC as mentioned in FIG. 11 or FIG. 12 to indicate a CC for transmitting the A-SRS among a plurality of CCs configured in the terminal. It performs the function of generating identification information. That is, the A-SRS transmission target CC identification information may be set to indicate A-SRS transmission for up to three CCs, and in some cases, two CCs may be instructed to transmit A-SRS simultaneously.

Of course, this is the case where the A-SRS transmission target CC identification information is 2 bits, but in some cases, the A-SRS transmission target CC identification information may be 2 bits or more, in which case more A-SRS transmission CC or combination thereof It may be displayed.

의 부호화 정보를 생성하는 채널 코딩부(Channel Coder)와, 부호화된 블록을 레이트 매칭(Rate Matching)하여

정보를 생성하는 레이트 매칭부(Rate Matcher)를 포함할 수 있을 것이다.In addition, although not shown, the DCI processing unit 1520 multiplexes the information of the total A bits (a ₀ to a _A-1 ) including the 2-bit A-SRS transmission target CC identification information according to an embodiment of the present invention. A CRC is added to the information element multiplexer and the information of the total A bits (a ₀ to a _A-1 ) to add c ₀ , c ₁ ,. a CRC Attacher for generating information bits of c _{K -1} , and c ₀ , c ₁ ,... c After receiving and encoding the information bits of _{K -1}

Rate coding the coded block with a channel coder for generating encoded information of

It may include a rate matcher for generating information.

The PDCCH transmitter 1530 allocates DCI information generated according to the present embodiment to the corresponding resource space of a specific subframe, performs OFDM modulation, and then transmits the DCI information to the terminal through the PDCCH.

The A-SRS receiving unit 1540 generates and transmits the A-SRS using the A-SRS transmission target CC determined by the A-SRS transmission target CC identification information and the A-SRS configuration parameters matched with the CC. Perform the function of receiving it.

Optionally, the CC-specific A-SRS configuration parameter information processor 1550 generates CC-specific A-SRS configuration parameter information for use when the UE transmits A-SRS to each of the A-SRS transmission target CCs, thereby generating RRC signaling and the like. Performs a function of transmitting to the terminal.

Of course, in the A-SRS receiving apparatus of FIG. 15, the DCI may be defined by the definition of DCI format 4, and the CC transmitting the DCI or the PDCCH and the CC for transmitting the A-SRS may not be the same. (For example, the CC transmitting the A-SRS configuration parameter information for each PDCCH and CC is a PCC, and accordingly, the UL CC transmitting the A-SRS may be an SCC, and the A-SRS configuration parameter for each PDCCH and CC may be used. CC transmitting information is PCC or SCC, and accordingly, UL CC transmitting A-SRS may be separate CC except PCC and SCC)

16 is a flowchart illustrating an A-SRS transmission method according to an embodiment of the present invention.

In principle, the A-SRS transmission method according to an embodiment is performed by the terminal. However, when the reference signal to which the present embodiment is applied is a downlink reference signal, it may be performed by the base station.

The A-SRS transmission method according to the present embodiment comprises the steps of receiving A-SRS configuration parameter information to be used by the A-SRS transmission target CC through separate higher-end signaling (S1610), and A-SRS transmission target CC identification information. Receiving a DCI including (S1620), Determining the A-SRS transmission target CC to transmit the A-SRS based on the A-SRS transmission target CC identification information (S1630), The A-SRS transmission target Determining the A-SRS configuration parameter information to be used by the CC (S1640), and generating the A-SRS using the determined A-SRS configuration parameter information and transmitting through the A-SRS transmission target CC (S1650) It may be configured to include).

Hereinafter, each step will be described in more detail.

First, the UE receives the A-SRS configuration parameter information to be used by the A-SRS transmission target CC through RRC signaling. (S1610) In principle, the RRC signaling is performed through the CC transmitting the DCI, but is not limited thereto.

In addition, the terminal receives a DCI transmitted by the base station through the PDCCH (S1620). Of course, the receiving DCI may be data of DCI format 4 including 2 bits of A-SRS transmission target CC identification information, but is not limited thereto.

The A-SRS configuration parameter information includes SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), transmissionComb (transmission comb information), cyclic shift (cyclic shift information), number of antenna ports SrsHoppoingBandwidth (hopping bandwidth) Information), duration (duration information), etc., but is not limited thereto.

In addition, the A-SRS configuration parameter information received by the RRC in step S1610 may be a plurality of A-SRS configuration parameter set table that can be used by a single CC as shown in FIG. 9, or as shown in FIG. 11 or 12. It may also be a CC-specific A-SRS configuration parameter set table matched for each use separately.

Meanwhile, the terminal receiving the DCI and the A-SRS configuration parameter information determines the UL CC to which the A-SRS should be transmitted through the A-SRS transmission target CC identification information (2 bits) included in the DCI (S1630).

In particular, when determining the A-SRS transmission target CC, each of up to three CCs may be determined as the A-SRS transmission target CC as shown in FIG. 11, but as shown in FIG. 12, two or more CCs may be simultaneously determined as the A-SRS transmission target CC. You might decide. This may be implemented differently according to the number of bits of the A-SRS transmission target CC identification information and the number of UL CCs used by the terminal.

The A-SRS transmission target CC determined at this time may be the same CC as the CC which performed DCI transmission or RRC signaling, or may be different CCs.

In step S1640, the A-SRS configuration parameter set to be used by the corresponding A-SRS transmission target CC is determined using the A-SRS configuration parameter information for each CC received through the RRC as shown in FIG. 11 or 12.

In addition, S1650 is a process of generating an A-SRS using the determined A-SRS configuration parameter set information and transmitting the A-SRS to the eNB through the A-SRS transmission target CC.

Through the A-SRS transmitted in this way, the base station estimates the channel state of the corresponding A-SRS transmission CC and can be used for future scheduling. It is possible to accurately estimate the channel state.

17 is a functional block diagram of an A-SRS transmission apparatus according to an embodiment of the present invention.

The A-SRS transmitting apparatus 1700 according to an embodiment includes a DCI receiver 1710 that receives a DCI including the A-SRS transmission target CC identification information, and an A-SRS transmission target CC to be used by the A-SRS transmission target CC through RRC signaling. An RRC processing unit 1720 that receives SRS configuration parameter information, and an A-SRS transmission target CC determination unit 1730 that determines an A-SRS transmission target CC to which the A-SRS is transmitted based on the A-SRS transmission target CC identification information. ), An A-SRS configuration parameter determiner 1740 for determining A-SRS configuration parameter information to be used by the A-SRS transmission target CC, and an A-SRS generated using the determined A-SRS configuration parameter information. Thereafter, the A-SRS transmission unit may be configured to include an A-SRS transmission unit 1750 to transmit through the CC.

The A-SRS transmitter 1700 is preferably implemented in the terminal (UE) or separately implemented in conjunction with the terminal, but is not limited thereto.

The DCI receiver 1710 performs a function of receiving a DCI transmitted from a base station through a PDCCH, and the DCI received may be DCI format 4 data including 2 bits of A-SRS transmission target CC identification information, but is not limited thereto. It doesn't happen.

The RRC processing unit 1720 receives A-SRS configuration parameter information to be used by the A-SRS transmission target CC as RRC signaling, and the received A-SRS configuration parameter information may be used by a single CC as shown in FIG. 9. 11 may be an A-SRS configuration parameter set table, or as shown in FIG. 11 or FIG. 12, a plurality of CC-matched A-SRS configuration parameter set tables may be used individually.

On the other hand, the RRC signaling is carried out through the CC, that is, the PCC that transmits the DCI, but is not limited thereto. For each A-SRS configuration parameter set information, SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), and transmissionComb (transmission). Comb information), cyclic shift (cyclic shift information), number of antenna ports (antenna port number information), SrsHoppoingBandwidth (hopping bandwidth information), duration (duration information), and the like.

Of course, the DCI receiving unit 1710 and the RRC processing unit 1720 may be integrated into one component.

The A-SRS transmission target CC determination unit 1730 performs a function of determining the UL CC that should transmit the A-SRS through the A-SRS transmission target CC identification information (2 bits) included in the received DCI, The A-SRS transmission target CC determined when may be one of up to three CCs as shown in FIG. 11, but two or more CCs may be determined as A-SRS transmission target CCs simultaneously as shown in FIG. 12.

In addition, the determined A-SRS transmission target CC may be the same CC as the CC performing the DCI transmission or RRC signaling, A-SRS cross-carrier scheduling can be enabled as in the present invention and the DCI and RRC signaling CC Is PCC, and the determined A-SRS transmission target CC may be another SCC other than the PCC. In addition, the DCI and RRC signaling CC may be a PCC or SCC, and the determined A-SRS transmission target CC may be another CC other than the PCC and the SCC.

The A-SRS configuration parameter determiner 1740 uses the A-SRS configuration parameter set table for each CC received through the RRC as shown in FIG. 11 or FIG. 12 to determine the A-SRS to be used by the corresponding CC. Determine a set of configuration parameters.

The A-SRS transmitter 1750 generates an A-SRS using the determined A-SRS configuration parameter set information and transmits the A-SRS to the eNB via the A-SRS transmission target CC.

According to the above embodiments, in a communication system using a plurality of CCs, a CC for transmitting an aperiodic reference signal is indicated using downlink control information of a physical control channel, and a parameter required for aperiodic reference signal transmission. By separately signaling, a UE can stably transmit an aperiodic reference signal (for example, A-SRS) in a communication system using a plurality of CCs.

In particular, since uplink allocation (UL Grant) and A-SRS allocation of information of DCI format 4 may be configured for different CCs in a CA environment, more efficient A-SRS transmission may be indicated in a multi-cell environment. That is, since the DCI including the A-SRS transmission target CC identification information and the CC (for example, PCC) for transmitting the A-SRS configuration parameter information and the CC (for example, SCC) for actually transmitting the A-SRS may differ from each other. In the cell environment, there is an advantage in that channel estimation for UL CC is possible without uplink allocation for all UL CCs.

In addition, since the channel estimation for the UL CC is possible without uplink allocation for all UL CCs in a multi-cell environment, it is possible to provide a resource allocation opportunity, thereby providing a scheduling gain.

In addition, when there is no uplink data transmission (PUSCH) in the CC to transmit the A-SRS, since the A-SRS transmission can be indicated without a separate uplink allocation (UL grant), an unnecessary uplink for indicating the A-SRS transmission Link allocation can be prevented to reduce PDCCH signaling overhead.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

Claims (17)

A non-periodic reference signal receiving method by an aperiodic reference signal receiving apparatus in a wireless communication system using a plurality of component carriers (CC),
Generating and transmitting downlink control information of a physical control channel including carrier element identification information of aperiodic reference signal;
Receiving the aperiodic reference signal generated and transmitted by using the CC component information of the aperiodic reference signal and the aperiodic reference signal configuration parameter information for each component carrier signaled separately;
Aperiodic reference signal receiving method comprising a. The method of claim 1,
The aperiodic reference signal is an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS'), and the transmission target identification information of the aperiodic reference signal is A-SRS transmission target CC identification information. A non-periodic reference signal receiving method characterized in that. The method of claim 2,
The A-SRS transmission target component carrier identification information is aperiodic reference signal receiving method, characterized in that the two-bit information. The method of claim 2,
The physical control channel is a physical downlink control channel (PDCCH), and the downlink control information is DCI format 4 information, characterized in that the aperiodic reference signal receiving method. The method of claim 2,
The A-SRS configuration parameter information for each CC is transmitted by RRC signaling. The method of claim 2,
The A-SRS configuration parameter information for each CC includes A-SRS configuration parameter set information for each of two or more CCs. The method of claim 6,
The A-SRS configuration parameter set includes SrsBandwidth (bandwidth information), FrequencyDomainposition (band position information), transmissionComb (transmission comb information), cyclic shift (cyclic shift information), number of antenna ports (antenna port number information) SrsHoppoingBandwidth (hopping) Bandwidth information), duration (period information) information comprising a. The method of claim 2,
And the CC for transmitting the A-SRS transmission target CC identification information and the A-SRS transmission target CC are different. The method of claim 2,
The CC transmitting the A-SRS transmission target CC identification information is a primary component carrier (PCC) or a secondary component carrier (SCC), and the CC transmitting the A-SRS is a component carrier (SCC) other than the PCC and SCC. A non-periodic reference signal receiving method characterized in that. An apparatus for receiving an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC),
An A-SRS transmission target CC identification information generation unit for generating A-SRS transmission target CC identification information for indicating a CC for transmitting the A-SRS among a plurality of CCs configured in the terminal;
A DCI processing unit for generating downlink control information (DCI) including the generated A-SRS transmission target CC identification information;
A PDCCH transmitter for transmitting the generated DCI to the UE through a physical control channel;
An A-SRS receiver configured to receive an A-SRS transmitted by the terminal through the A-SRS transmission target CC determined as the A-SRS transmission target CC identification information;
Aperiodic sounding reference signal receiving apparatus comprising a. The method of claim 10,
The CC-based A-SRS configuration parameter information processing unit for generating a CC-specific A-SRS configuration parameter information for use when transmitting a plurality of CCs configured in the terminal and transmits to the terminal by RRC signaling, further comprising: Aperiodic sounding reference signal receiver. The method of claim 10,
A-SRS transmission target CC identification information included in the DCI is aperiodic sounding reference signal receiving apparatus, characterized in that the 2 bits information. A method of transmitting an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC),
Receiving a DCI including the A-SRS transmission target CC identification information through a physical control channel
Receiving A-SRS configuration parameter information to be used by an A-SRS transmission target CC through higher layer signaling separate from the physical control channel;
Determining an A-SRS transmission target CC to which an A-SRS is transmitted based on the A-SRS transmission target CC identification information;
Determining A-SRS configuration parameter information to be used by the A-SRS transmission target CC;
Generating an A-SRS using the determined A-SRS configuration parameter information and transmitting the A-SRS through the A-SRS transmission target CC;
Aperiodic sounding reference signal transmission method comprising a. The method of claim 13,
The CC receiving the DCI is a primary component carrier (PCC), the CC transmitting the A-SRS is a sub-cyclic carrier (SCC) characterized in that the aperiodic sounding reference signal transmission method. An apparatus for transmitting an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC),
A DCI receiver configured to receive a DCI including the A-SRS transmission target CC identification information through a physical control channel;
An RRC processing unit for receiving A-SRS configuration parameter information for each CC to be used by the A-SRS transmission target CC through RRC signaling;
An A-SRS transmission target CC determination unit which determines an A-SRS transmission target CC to which the A-SRS is to be transmitted based on the A-SRS transmission target CC identification information;
An A-SRS configuration parameter determiner for determining A-SRS configuration parameter information to be used by the A-SRS transmission target CC;
An A-SRS transmitter for generating an A-SRS using the determined A-SRS configuration parameter information and transmitting the A-SRS through the A-SRS transmission target CC;
Apparatus for aperiodic sounding reference signal comprising a. 16. The method of claim 15,
The A-SRS transmission target CC identification information included in the DCI is 2-bit information, and the A-SRS configuration parameter information for each CC is table information including an A-SRS configuration parameter set for each of two or more CCs. Aperiodic sounding reference signal transmitter. A method of transmitting and receiving an aperiodic sounding reference signal (hereinafter referred to as 'A-SRS') in a wireless communication system using a plurality of component carriers (CC),
In the A-SRS receiver, A-SRS transmission target element carrier identification information is included in downlink control information (DCI) of the physical control channel and transmitted to the SRS transmitter.
The SRS transmitting apparatus transmits the A-SRS through the A-SRS transmission target component carrier using the A-SRS transmission parameter information for each component carrier and the A-SRS transmission target component carrier identification information separately signaled from the physical control channel. Aperiodic sounding reference signal transmission and reception method, characterized in that.

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