KR20190086332A - Method and apparatus for transmission timing of aperiodic sounding reference signal in wireless cellular communication system - Google Patents

Abstract

The present disclosure relates to a communication technique for fusing a 5G communication system with IoT technology to support a higher data transmission rate than that of a 4G system, and a system thereof. The present disclosure can be applied to an intelligent service (for example, smart home, a smart building, a smart city, a smart car or a connected car, healthcare, digital education, retail business, security- and safety-related services, etc.) based on a 5G communication system and IoT-related technology. Disclosed in the present invention are a method and an apparatus for transmitting an aperiodic sounding reference signal (SRS) in a new radio (NR) system.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a method and apparatus for determining an aperiodic SRS transmission timing in a wireless cellular communication system,

The present invention relates to a wireless communication system, and more particularly, to a method and apparatus for determining transmission timing of an aperiodic Sounding Reference Signal (SRS). Also, we propose a method and apparatus for setting transmission timing in SRS antenna switching operation.

Efforts are underway to develop an improved 5G or pre-5G communication system to meet the growing demand for wireless data traffic after commercialization of the 4G communication system. For this reason, a 5G communication system or a pre-5G communication system is called a system after a 4G network (Beyond 4G network) communication system or after a LTE system (Post LTE). To achieve a high data rate, 5G communication systems are being considered for implementation in very high frequency (mmWave) bands (e.g., 60 gigahertz (60GHz) bands). In order to mitigate the path loss of the radio wave in the very high frequency band and to increase the propagation distance of the radio wave, in the 5G communication system, beamforming, massive MIMO, full-dimension MIMO (FD-MIMO ), Array antennas, analog beam-forming, and large scale antenna technologies are being discussed. In order to improve the network of the system, the 5G communication system has developed an advanced small cell, an advanced small cell, a cloud radio access network (cloud RAN), an ultra-dense network, (D2D), a wireless backhaul, a moving network, cooperative communication, Coordinated Multi-Points (CoMP), and interference cancellation Have been developed. In addition, in the 5G system, the Advanced Coding Modulation (ACM) scheme, Hybrid FSK and QAM Modulation (FQAM) and Sliding Window Superposition Coding (SWSC), the advanced connection technology, Filter Bank Multi Carrier (FBMC) (non-orthogonal multiple access), and SCMA (sparse code multiple access).

On the other hand, the Internet is evolving into an Internet of Things (IoT) network in which information is exchanged between distributed components such as objects in a human-centered connection network where humans generate and consume information. IoE (Internet of Everything) technology, which combines IoT technology with big data processing technology through connection with cloud servers, is also emerging. In order to implement IoT, technology elements such as sensing technology, wired / wireless communication, network infrastructure, service interface technology and security technology are required. In recent years, sensor network, machine to machine , M2M), and MTC (Machine Type Communication). In the IoT environment, an intelligent IT (Internet Technology) service can be provided that collects and analyzes data generated from connected objects to create new value in human life. IoT is a field of smart home, smart building, smart city, smart car or connected car, smart grid, health care, smart home appliance, and advanced medical service through fusion of existing information technology . ≪ / RTI >

Accordingly, various attempts have been made to apply the 5G communication system to the IoT network. For example, technologies such as a sensor network, a machine to machine (M2M), and a machine type communication (MTC) are implemented by techniques such as beamforming, MIMO, and array antennas It is. The application of the cloud RAN as the big data processing technology described above is an example of the convergence of 5G technology and IoT technology.

In the NR system, the UE can transmit SRS, and in particular, it is possible to transmit aperiodic SRS.

When the NR system transmits aperiodic SRS, it has to determine the transmission timing. For NR systems, one or more SRS resource sets are configurable and one or more SRS resource configurations are possible in one SRS resource set. A method of setting a transmission timing offset value for non-periodic SRS transmission when non-periodic SRS transmission is triggered can be considered. Assuming that the A-SRS triggering offset value X is set and that the X value is set in the slot unit, it is possible to set the non-periodic SRS to be transmitted to the X slot after the aperiodic SRS transmission is triggered. In the present invention, intra / inter-slot antenna switching is performed on the assumption that the offset value X is set on the basis of one SRS resource set and on the basis of one SRS resource.

According to an aspect of the present invention, there is provided a method of processing a control signal in a wireless communication system, the method comprising: receiving a first control signal transmitted from a base station; Processing the received first control signal; And transmitting the second control signal generated based on the process to the base station.

As described above, the present invention relates to a method and apparatus for determining transmission timing of an aperiodic Sounding Reference Signal (SRS). Also, we propose a method to set transmission timing in SRS antenna switching operation. This facilitates the SRS-related setup of the base station according to the scenario during the SRS transmission, and enables the SRS transmission at a predetermined time point and the SRS enhanced reception of the base station to be expected.

1 is a diagram illustrating a basic structure of a time-frequency domain, which is a radio resource region in which data or a control channel is transmitted in an NR system.
2 is a diagram illustrating an uplink transmission structure of NR.
FIG. 3 is a diagram illustrating a structure in which SRS is allocated to each subband according to the prior art.
4 is a diagram illustrating an example of how an antenna can be mapped to SRS resources when SRS antenna switching is considered.
5 illustrates an example in which an aperiodic SRS is transmitted at n + X through the setting of aperiodic SRS triggering offset X, assuming that triggering for aperiodic SRS occurs in slot n.
FIG. 6 is a diagram illustrating an example of determining the timing at which an aperiodic SRS is transmitted through the setting of aperiodic SRS triggering offset X, assuming that triggering for aperiodic SRS occurs in slot n.
FIG. 7 is a diagram illustrating an order flow between base station units for timing of aperiodic SRS transmission together with an antenna switching operation. FIG.
8 is a view showing the operation of the base station side for timing setting in the aperiodic SRS transmission together with the antenna switching operation.
9 is a diagram illustrating terminal side operation for setting timing for aperiodic SRS transmission together with antenna switching operation.
FIG. 10 is a diagram illustrating another example of supporting SRS antenna switching for aperiodic SRS transmission.
11 is a block diagram showing an internal structure of a terminal according to an embodiment of the present invention.
12 is a block diagram showing an internal structure of a base station according to an embodiment of the present invention.
FIGS. 13 and 14 illustrate an embodiment of the present invention for solving the case where an SRS transmission area is not guaranteed in an aperiodic SRS transmission.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the embodiments of the present invention, descriptions of techniques which are well known in the technical field of the present invention and are not directly related to the present invention will be omitted. This is for the sake of clarity of the present invention without omitting the unnecessary explanation.

For the same reason, some of the components in the drawings are exaggerated, omitted, or schematically illustrated. Also, the size of each component does not entirely reflect the actual size. In the drawings, the same or corresponding components are denoted by the same reference numerals.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

At this point, it will be appreciated that the combinations of blocks and flowchart illustrations in the process flow diagrams may be performed by computer program instructions. These computer program instructions may be loaded into a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, so that those instructions, which are executed through a processor of a computer or other programmable data processing apparatus, Thereby creating means for performing functions. These computer program instructions may also be stored in a computer usable or computer readable memory capable of directing a computer or other programmable data processing apparatus to implement the functionality in a particular manner so that the computer usable or computer readable memory The instructions stored in the block diagram (s) are also capable of producing manufacturing items containing instruction means for performing the functions described in the flowchart block (s). Computer program instructions may also be stored on a computer or other programmable data processing equipment so that a series of operating steps may be performed on a computer or other programmable data processing equipment to create a computer- It is also possible for the instructions to perform the processing equipment to provide steps for executing the functions described in the flowchart block (s).

In addition, each block may represent a portion of a module, segment, or code that includes one or more executable instructions for executing the specified logical function (s). It should also be noted that in some alternative implementations, the functions mentioned in the blocks may occur out of order. For example, two blocks shown in succession may actually be executed substantially concurrently, or the blocks may sometimes be performed in reverse order according to the corresponding function.

Herein, the term " part " used in the present embodiment means a hardware component such as software or an FPGA or an ASIC, and 'part' performs certain roles. However, 'part' is not meant to be limited to software or hardware. &Quot; to " may be configured to reside on an addressable storage medium and may be configured to play one or more processors. Thus, by way of example, 'parts' may refer to components such as software components, object-oriented software components, class components and task components, and processes, functions, , Subroutines, segments of program code, drivers, firmware, microcode, circuitry, data, databases, data structures, tables, arrays, and variables. The functions provided in the components and components may be further combined with a smaller number of components and components or further components and components. In addition, the components and components may be implemented to play back one or more CPUs in a device or a secure multimedia card. Also, in an embodiment, 'to' may include one or more processors.

For example, 3GPP's High Speed Packet Access (HSPA), LTE (Long Term Evolution or Evolved Universal Terrestrial Radio Access (E-UTRA)), LTE-Advanced To a broadband wireless communication system that provides high-speed, high-quality packet data services such as the LTE-A, 3GPP2 high rate packet data (HRPD), UMB (Ultra Mobile Broadband), and IEEE 802.16e communication standards. . In addition, a 5G or NR (new radio) communication standard is being produced with the fifth generation wireless communication system.

In the NR system, an OFDM (Orthogonal Frequency Division Multiplexing) scheme is used in a downlink (DL) and a DFT spread orthogonal (DFT-S-OFDM) scheme is used in an uplink Frequency Division Multiplexing (OFDM) and OFDM. The uplink refers to a radio link through which a UE (User Equipment) or an MS (Mobile Station) transmits data or control signals to a base station (eNode B or base station (BS) The term " wireless link " In the above multiple access scheme, the data or control information of each user is classified and operated so that the time and frequency resources for transmitting data or control information for each user do not overlap each other, that is, orthogonality is established. do.

1 is a diagram illustrating a basic structure of a time-frequency domain, which is a radio resource region in which data or a control channel is transmitted in an NR system.

)을 구성한다. 그리고 NR에서 지원하는 Numerology에 따라서 여러 개의 심볼이 보여 하나의 서브프레임(110)을 구성한다. 하나의 서브프레임은 1msec로 정의된다. 서브프레임을 구성하는 OFDM 심벌 혹은 DFT-S-OFDM 심벌 수는 아래 표1 및 표2와 같다.Referring to Fig. 1, the abscissa represents the time domain and the ordinate axis represents the frequency domain. The minimum transmission unit in the time domain is the OFDM symbol for the uplink, the OFDM symbol or the DFT-S-OFDM symbol for the downlink, and the 14 symbols for the NCP (normal cyclic prefix)

). A plurality of symbols are displayed according to Numerology supported by the NR, and one subframe 110 is formed. One subframe is defined as 1 msec. The number of OFDM symbols or DFT-S-OFDM symbols constituting a subframe is shown in Tables 1 and 2 below.

for normal cyclic prefix [Table 1] Number of OFDM symbols per slot,

for normal cyclic prefix

, for extended cyclic prefix [Table 2] Number of OFDM symbols per slot,

, for extended cyclic prefix

개의 서브캐리어로 구성된다. 여기서

의 값은 상향링크과 하향링크에 대하여 표2에 주어져 있다. 그리고 N_sc ^RB 은 리소스 블록 (120, Resource Block)으로 주파수 영역에서 12개의 연속된 서브캐리어로 정의된다. 시간-주파수영역에서 자원의 기본 단위는 리소스 엘리먼트(Resource Element; RE, 130)로서 OFDM/DFT-S-OFDM 심벌 인덱스 및 서브캐리어 인덱스로 정의할 수 있다.The minimum transmission unit in the frequency domain is the subcarrier, and the overall system transmission bandwidth is the total

Lt; / RTI > subcarriers. here

Is given in Table 2 for the uplink and the downlink. And N _sc ^RB is a resource block 120 defined as 12 consecutive subcarriers in the frequency domain. In a time-frequency domain, a basic unit of a resource can be defined as a resource element (RE) 130 as an OFDM / DFT-S-OFDM symbol index and a subcarrier index.

[Table 3]

In a wireless communication system, a multi-antenna technique is applied as one of techniques for improving uplink performance. As a representative example, a base station can improve the uplink performance by using up to four transmit antennas in the uplink through the SU-MIMO scheme. To do so, the base station estimates the channel state for the entire uplink transmission band for each transmission antenna of each terminal, and determines a precoding matrix to be used by each terminal. The base station can receive SRS (Sounding Reference Signal) transmitted from each terminal and acquire uplink channel information for each terminal. The base station performs uplink frequency selective scheduling, power control, and MCS (Modulation and Coding Scheme) level selection including the precoding matrix determination based on the acquired uplink channel information for each UE.

2 is a diagram illustrating an uplink transmission structure of NR.

Referring to FIG. 2, the basic unit of NR transmission is a slot 100. Assuming a general CP (Cyclic Prefix) length, each slot is composed of 14 symbols 101, and one symbol is one UL (CP-OFDM or DFT-S-OFDM) symbols.

A resource block (RB) 102 is a resource allocation unit corresponding to one slot based on a time domain, and is composed of 12 subcarriers based on a frequency domain.

The uplink structure is divided into a data area and a control area. Unlike the LTE system, in the NR system, the control region can be set and transmitted at an arbitrary position in the uplink by the setting. Here, the data area includes a series of communication resources including data such as voice and packet transmitted to each terminal, and corresponds to the remaining resources except the control area in the subframe. The control region includes a series of communication resources for a downlink channel quality report from each terminal, a reception ACK / NACK for a downlink signal, an uplink scheduling request, and the like.

The terminal can simultaneously transmit its own data and control information in the data area and the control area. The symbol for which the UE periodically transmits the SRS within one slot is at least the last six symbol intervals 103 based on the current 3GPP NR agreement, and more than six symbols may be extended to an SRS transmittable area in the future. When transmitted in the frequency domain, it is transmitted in multiples of 4 RBs and can be transmitted at a maximum of 272 RBs. Also, in NR system, the number of symbols N of SRS can be set to 1, 2, 4 and can be transmitted in consecutive symbols. The NR system also allows repeated transmission of SRS symbols. Specifically, the repetition factor of the SRS symbol can be set to r ∈ {1,2,4} where r ≤ N. For example, when one SRS antenna is mapped to one symbol and transmitted, up to four symbols can be repeatedly transmitted. Alternatively, four different antenna ports may be transmitted on four symbols. In this case, repeated transmission of the SRS symbol is not allowed since each antenna port is mapped to one symbol.

The SRS is composed of a CAZAC (Constant Amplitude Zero Auto Correlation) sequence. The CAZAC sequences constituting each SRS transmitted from a plurality of terminals have different cyclic shift values. Also, CAZAC sequences generated through a cyclic shift in one CAZAC sequence have characteristics that have zero correlation values with sequences having different cyclic shift values from each other. The SRSs assigned to the same frequency domain at the same time using these characteristics can be classified according to the CAZAC sequence cyclic shift value set for each SRS in the base station.

The SRSs of the UEs can be classified according to the frequency position as well as the cyclic-shift value. The frequency position is divided into SRS subband unit allocation or Comb. In NR system, Comb2 and Comb4 are supported. In Comb2, one SRS is allocated only to even or odd subcarriers in the SRS subband, and each of even-numbered subcarriers and odd- .

Each terminal is allocated an SRS subband based on a tree structure. The UE performs hopping to the SRS allocated to each subband at each SRS transmission time. Accordingly, all the transmit antennas of the UE can transmit the SRS to the entire uplink data transmission bandwidth.

FIG. 3 is a diagram illustrating a structure in which SRS is allocated to each subband according to the prior art.

Referring to FIG. 3, SRS is allocated to each MS according to a tree structure set by a BS when a data transmission band corresponding to 40 RBs is provided on a frequency band.

In this example, when the level index of the tree structure is b, the highest level (b = 0) of the tree structure is composed of one SRS subband of 40RB bandwidth. At the second level (b = 1), two SRS subbands of 20RB bandwidth are generated from SRS subbands at level b = 0. Therefore, there are two SRS subbands in the entire data transmission band of the second level (b = 1). At the third level (b = 2), five 4RB SRS subbands are generated from one 20RB SRS subband at the immediately upper level (b = 1), and 10 4RB SRS subbands exist within one level.

The structure of such a tree structure has various levels of number of levels, SRS subband size, and SRS subband number per level, depending on the setting of the base station. Where the number of SRS subbands at level b generated from one higher-level SRS subband is Nb, and the index for this Nb SRS subbands is nb = {0, ..., , Nb-1}. As shown in FIG. 2, the subbands are assigned to subbands for each level. For example, terminal 1 200 is allocated to the first SRS subband (n1 = 0) of two SRS subbands having a bandwidth of 20RB at b = 1 level, and terminal 2 201 and terminal 3 202 Can be allocated to the first SRS subband (n2 = 0) and the third SRS subband (n2 = 2) under the second 20RB SRS subband. Through these procedures, the UE can simultaneously transmit SRS through a plurality of CCs, and can transmit SRSs in a plurality of SRS subbands simultaneously within one CC.

As mentioned above, the NR terminal supports the SU-MIMO scheme and has up to four transmit antennas. It is also possible to simultaneously transmit SRSs to multiple CCs, or to multiple SRS subbands in a CC. Unlike the LTE system, various numerologies are supported for the NR system, SRS transmission symbols can be variously set, and repeated transmission of the SRS transmission can be allowed. However, the NR system also decided to support SRS antenna switching for 1Tx (in the case of UE with 1T2R), 2Tx in the case of UE with 2T4R, and 4Tx in the case of UE with 1T4R. In the NR system, it is considered that it is important to construct four receiving antennas in the UE. In order to obtain all the channel information for the four receiving antennas considering the channel satisfying the UL / DL reciprocity, the SRS antenna switching should be effectively supported do. Therefore, it is necessary to transfer the SRS antenna using the multiple antennas in the NR system and to provide various techniques for operating the SRS antenna.

In case of SRS transmission, one or more SRS resource sets can be set as an upper layer in the NR terminal. And, each SRS resource set can be set to K ≥ 1 SRS resource as an upper layer. The SRS resource set can be determined according to the SRS-SetUse set in the upper layer. SRS-SetUse can be set to beamManagement, Codebook, NonCodbook, and Antenna switching. For example, when SRS-SetUse is set to Antenna switching, one SRS resource set can be set and the number of SRS resources set according to the antenna switching method can be changed. The NR terminal divides SRS resource transmission into two trigger types depending on whether it follows higher layer configuration or DCI setting.

● Trigger type 0: higher layer signaling

● Trigger type 1: DCI format

In the NR system, periodic, semi-persistent, and aperiodic transmission methods can be set for SRS transmission. According to the present 3GPP NR agreement, in case of periodic and semi-persistent transmission, the period and slot offset value for SRS transmission can be set by RRC as shown in Table 4 below. In case of semi-periodic SRS transmission, the SRS resource set for the semi-periodic SRS transmission by MAC CE can be enabled / disabled.

[Table 4] UE Specific SRS Periodicity and Slot Offset Configuration for trigger type 0

In case of aperiodic SRS transmission, non-periodic SRS transmission is triggered based on SRS resource set through DCI, and SRS resource set set in RRC can be set through 2bits aperiodic SRS request field in Table 5 below.

[Table 5] SRS request value for trigger type 1

In Table 5, codepoint " 00 " indicates that aperiodic SRS transmission is not set. However, there is no discussion of a specific method for transmitting aperiodic SRS when an aperiodic SRS transmission is triggered in the case of an aperiodic SRS transmission as opposed to a periodic and semi-persistent transmission.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiments of the present invention will be described below as an example of the NR system, but the embodiments of the present invention may be applied to other communication systems having a similar technical background or channel form. Therefore, the embodiments of the present invention can be applied to other communication systems by a person skilled in the art without departing from the scope of the present invention.

In the following description of the present invention, 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. The following terms are defined in consideration of the functions of the present invention, and these may be changed according to the intention of the user, the operator, or the like. Therefore, the definition should be based on the contents throughout this specification. Hereinafter, the base station may be at least one of an eNode B, a Node B, a base station (BS), a wireless access unit, a base station controller, or a node on a network. The terminal may include a user equipment (UE), a mobile station (MS), a cellular phone, a smart phone, a computer, or a multimedia system capable of performing communication functions. In the present invention, an uplink (UL) refers to a wireless transmission path of a signal transmitted from a terminal to a base station.

In the first exemplary embodiment of the present invention described below, a method of setting the transmission time point of the aperiodic SRS based on one SRS resource when the aperiodic SRS transmission is triggered is proposed. In the second embodiment, a method of setting the transmission time point of the aperiodic SRS based on one SRS resource set when the aperiodic SRS transmission is triggered is proposed. In the third embodiment, when SRS antenna switching is supported for 1Tx (in the case of UE with 1T2R), 2Tx (in the case of UE with 2T4R) and 4Tx (in the case of UE with 1T4R) We propose a selection method. In the fourth embodiment, a method of setting the transmission timing when the SRS antenna switching proposed in the third embodiment is applied through the method of the first embodiment is proposed. In the fifth embodiment, a method of setting the transmission timing when the SRS antenna switching proposed in the third embodiment is applied through the method of the second embodiment is proposed. Finally, the sixth embodiment specifically describes the base station setting and the terminal operation for the timing of the aperiodic SRS transmission together with the antenna switching operation described in the fourth and fifth embodiments through the flowchart of FIG.

≪ Embodiment 1 >

The first embodiment proposes a method of setting a transmission time point of an aperiodic SRS based on one SRS resource when an aperiodic SRS transmission is triggered. When the NR system transmits aperiodic SRS, it has to determine the transmission timing. For NR systems, one or more SRS resource sets are configurable and one or more SRS resource configurations are possible in one SRS resource set. A method of setting a transmission timing offset value X for an aperiodic SRS transmission when an aperiodic SRS transmission is triggered can be considered. At this time, if it is assumed that the offset value X is set to RRC and that the X value is set in the slot unit, it is possible to set the non-periodic SRS to be transmitted to the X slot after the aperiodic SRS transmission is triggered. In this case, the second embodiment proposes a method in which the offset value X is set based on one SRS resource. Specifically, a method of setting an offset value for non-periodic SRS triggering based on one SRS resource is described in Table 7 below.

[Table 6] How the offset value for non-periodic SRS triggering is set based on one SRS resource

More specifically, the SRS resource related parameters set in the RRC in Table 6 are shown. As described above, when the offset value X is set based on one SRS resource, the AperiodicSRS-TriggeringOffset value can be further introduced to the SRS resource setting information. The AperiodicSRS-TriggeringOffset value X can be set to an appropriate value depending on the base station implementation, and the value range can be set from 0 to maxAperiodicSRS-TriggeringOffsetValue to set a maximum value. Therefore, it is assumed that the triggering for the aperiodic SRS occurs in slot n, and the setting of the aperiodic SRS triggering offset X can set the time at which the aperiodic SRS is transmitted in n + X for each SRS resource.

≪ Embodiment 2 >

The second embodiment proposes a method of setting the transmission time point of the aperiodic SRS based on one SRS resource set when the aperiodic SRS transmission is triggered. When the NR system transmits aperiodic SRS, it has to determine the transmission timing. For NR systems, one or more SRS resource sets are configurable and one or more SRS resource configurations are possible in one SRS resource set. A method of setting a transmission timing offset value X for an aperiodic SRS transmission when an aperiodic SRS transmission is triggered can be considered. At this time, if it is assumed that the offset value X is set to RRC and that the X value is set in the slot unit, it is possible to set the non-periodic SRS to be transmitted to the X slot after the aperiodic SRS transmission is triggered. In this case, in the first embodiment, a method of setting an offset value X based on one SRS resource set is proposed. Specifically, a method of setting an offset value for non-periodic SRS triggering based on one SRS resource set will be described with reference to Table 6 below.

[Table 7] How the offset value for non-periodic SRS triggering is set based on one SRS resource set

More specifically, SRS resource set related parameters set in the RRC in Table 7 are shown. As described above, when the offset value X is set based on one SRS resource set, the AperiodicSRS-TriggeringOffset value can be further introduced to the SRS resource setting information. The AperiodicSRS-TriggeringOffset value X can be set to an appropriate value depending on the base station implementation, and the value range can be set from 0 to maxAperiodicSRS-TriggeringOffsetValue to set a maximum value. Therefore, it is assumed that the triggering for the aperiodic SRS occurs in slot n, and the time when the aperiodic SRS is transmitted in n + X through the setting of the aperiodic SRS triggering offset X can be set for each SRS resource set.

≪ Third Embodiment >

The third embodiment considers frequency hopping when SRS antenna switching is supported for 1Tx (in the case of UE with 1T2R), 2Tx (in the case of UE with 2T4R) and 4Tx (in the case of UE with 1T4R) We propose an antenna selection method. In the NR system, it is considered that it is important to construct four receiving antennas in the UE. In order to obtain all the channel information for the four receiving antennas considering the channel satisfying the UL / DL reciprocity, the SRS antenna switching should be effectively supported do. Specifically, when a terminal has R receive antennas but transmits to a maximum of T antenna ports, when R > T, the base station measures all channels for R antennas to measure all DL channels from the UL SRS Should be able to. Therefore, SRS antenna switching is required for this. NR system supports SRS antenna switching for (R, T) = (2,1), (4,1), and (4,2), and more specifically, FIG. 4 shows the operation principle of SRS antenna switching Explain it. As described above, in the NR system, the symbol number N of the SRS can be set to 1, 2, 4 and can be transmitted in consecutive symbols. The NR system also allows repeated transmission of SRS symbols. Specifically, the repetition factor of the SRS symbol can be set to r ∈ {1,2,4} where r ≤ N.

4 is a diagram illustrating an example of how an antenna can be mapped to SRS resources when SRS antenna switching is considered. For example, FIG. 10 shows a case where (R, T) = (2,1) is transmitted through two SRS symbols. In this case, N = 2, r = 1, one SRS resource is defined for each symbol, and different antennas p0 and p1 can be transmitted in each SRS resource. Figure d20 shows another case in which (R, T) = (2,1) is transmitted over four SRS symbols. In this case, N = 4 and r = 2, one SRS resource is defined for two neighboring symbols, and different antennas p0 and p1 can be transmitted in each SRS resource. FIG. 30 shows a case where (R, T) = (4,2) is transmitted through two SRS symbols. In this case, N = 2 and r = 1, one SRS resource is defined for each symbol, and two antennas pair0 (p0, p2) and pair1 (p1, p3) can be transmitted in each SRS resource. Here, the two antenna port pairs are composed of SRS port 0, 2 and port 1, 3, respectively, so that a coherent port is selected in consideration of UL codebook design. NR system, the UL codebook design consists of full, partial, and non-coherent precoder. In case of partial precoder, pair0 (p0, p2) and pair1 (p1, p3) are designed to coherent with 4 SRS ports have. Therefore, it is natural to select pair0 (p0, p2) and pair1 (p1, p3) when two are selected from four SRS ports considering the UL codebook characteristic. Also, when considering the multi-panel structure, port0 and 1 correspond to +45 pol and ports2 and 3 correspond to -45 pol. Therefore, it is natural to select pair0 (p0, p2), pair1 (p1, p3) when two of the four SRS ports are selected even when considering the panel selection side. FIG. 40 shows another case in which (R, T) = (4,2) is transmitted over four SRS symbols. In this case, N = 4 and r = 2, one SRS resource is defined for two neighboring symbols, and two antennas pair0 (p0, p2) and pair1 (p1, p3) have. The reason for selecting pair0 (p0, p2) and pair1 (p1, p3) in the case of selecting two in four SRS ports has been described above. Next, d50 is transmitted through four SRS symbols for (R, T) = (4, 1). In this case, N = 4 and r = 1, one SRS resource is defined for each symbol, and different antennas p0, p1, p2 and p3 can be transmitted in each SRS resource.

The number of SRS symbols used in the SRS antenna switching operation for (R, T) = (2,1), (4,1) and (4,2) described above depends on the Tx switching time (Y) . According to the input of RAN4, which is necessary for antenna switching, Tx switching time is required to be 15 μs. Therefore, considering 15kHz numerology, at least one symbol must be set to Y because the length of one symbol excluding CP is 66.67 μs. At this time, the maximum number of SRS symbols required is Y = 3 symbols for (R, T) = (4, 1), and a maximum of 7 symbols is required. Therefore, according to the current 3GPP NR agreement, the area where the SRS can be transmitted is the last six symbols of the slot. Therefore, in order to support intra-slot antenna switching for (R, T) = (2,1), (4,1), and (4,2) for at least 15 kHz numerology, Must be set to 7 symbols. In the NR system, intra- / inter-slot antenna switching can be considered for antenna switching because the number of symbols of the SRS can be set to N? {1,2,4} in one slot and periodic, Antenna switching can be distinguished according to semi-persistent and aperiodic transmission methods as follows.

● For periodic and semi-persistent SRS transmission,

■ Intra-slot antenna switching only

■ Inter-slot antenna switching only

■ Intra + inter-slot antenna switching

● For aperiodic SRS transmission,

■ Intra-slot antenna switching only

■ Inter-slot antenna switching only

■ Intra + inter-slot antenna switching

A more specific method of operating the intra- / inter-slot antenna switching for aperiodic SRS transmission will now be described in detail in the fourth and fifth embodiments.

In the present invention, the principle of SRS hopping and antenna selection pattern considering frequency hopping in SRS antenna switching is summarized as follows.

● Method 1: Antenna switching is supported to enable channel estimation for all antenna ports in one SRS subband.

● Method 2: An antenna selection is made so that the base station uniformly generates frequency hopping in the established SRS bandwidth so as to advantageously quickly obtain approximate channel information for the entire SRS transmission band in a short time.

● Method 3: When transmitting multiple SRS antennas at the same time, the port is selected and paring considering the UL codebook design and multi-panel characteristics.

는 SRS 전송에 대한 counting index를 나타내며 SRS가 전송되는 index

에 대하여 4개의 SRS 서브밴드 중 하나의 서브밴드에서 SRS 전송이 발생된다. 상기 제안 방법에 의해 SRS 호핑 및 안테나 선택을 할 경우 (R, T)=(2,1)에 대한 예시가 표8에 도시되었다. 표8에 따르면

가 총 8번에 걸쳐 일어나는 동안 설정된 전체 SRS 송신 대역에 대해 SRS 안테나 포트 0과 1에 대한 전송이 모두 이루어지게 된다.More specifically, in Table 8, Table 9, and Table 10, it is assumed that 1Tx (in the case of UE with 1T2R), 2Tx in the case of UE with 2T4R, and 4Tx (in the case of UE with 1T4R) An example of an antenna selection method when SRS antenna switching is supported is shown. In this example, the SRS bandwidth is divided into four SRS subbands. And frequency hopping occurs in SRS transmission. Tables 8, 9, and 10

Indicates the counting index for the SRS transmission, and the index at which the SRS is transmitted

The SRS transmission occurs in one of the four SRS subbands. An example of (R, T) = (2, 1) when SRS hopping and antenna selection are performed by the proposed method is shown in Table 8. According to Table 8

The transmission for both the SRS antenna ports 0 and 1 is performed for the entire set SRS transmission band.

[Table 8] An example of antenna switching with SRS frequency hopping, (R, T) = (2,1)

가 총 16번에 걸쳐 일어나는 동안 설정된 전체 SRS 송신 대역에 대해 SRS 안테나 포트 0~3에 대한 전송이 모두 이루어지게 된다. 표8와 비교하여 4개의 안테나 포트를 기지국에게 모두 보여주기 위해서 2배의

가 요구된다. 하지만 상기 방법2에 의해서

가 15에 다다르기 전에도 전체 SRS 송신 대역에 대한 대략적인 채널 정보를 획득할 수 있다. An example of (R, T) = (4,1) when SRS hopping and antenna selection are performed by the proposed method is shown in Table 9. According to Table 9

All of the transmissions to the SRS antenna ports 0 to 3 are performed for the entire set SRS transmission band. In comparison with Table 8, in order to show four antenna ports to the base station,

Is required. However, according to the method 2

It is possible to obtain approximate channel information for the entire SRS transmission band even before reaching the 15th.

[Table 9] An example of antenna switching with SRS frequency hopping, (R, T) = (4,1)

가 총 8번에 걸쳐 일어나는 동안 설정된 전체 SRS 송신 대역에 대해 SRS 안테나 포트 0~3에 대한 전송이 모두 이루어지게 된다. 표10에서는 표9과 비교하여 한번에 2개의 안테나 전송이 이루어지기 때문에 전체 SRS 송신 대역에 대한 채널을 모두 획득하는데 1/2배의

가 요구된다. 또한 두 개의 안테나 동시 전송 시 안테나 pair가 pair0(p0, p2), pair1(p1, p3)로 이루어졌다. 이는 상기 방법3에 의해 제안된 방법으로 UL 코드북 디자인과 multi-panel 특성을 고려하여 port가 pairing되는 것을 고려한 방법이다. An example of (R, T) = (4,2) when SRS hopping and antenna selection are performed by the proposed method is shown in Table 10. According to Table 10

All of the transmissions for the SRS antenna ports 0 to 3 are performed for the entire set SRS transmission band. In Table 10, since two antennas are transmitted at a time in comparison with Table 9, all the channels for the entire SRS transmission band are obtained.

Is required. Also, when two antennas are simultaneously transmitted, the antenna pairs are composed of pair0 (p0, p2) and pair1 (p1, p3). This is a method considering the pairing of ports considering the UL codebook design and multi-panel characteristics in the method proposed by the method 3 above.

[Table 10] An example of antenna switching with SRS frequency hopping, (R, T) = (4,2)

및 두 개의 안테나 선택에 대한 포트 pair 인덱스

가 정의된다.Antenna selection method when SRS antenna switching is supported by the proposed method will be described in more detail with reference to Table 11 below. In Table 11, when the UE supports antenna selection for SRS antenna switching, a port index

And the port pair index for the two antenna selections

Is defined.

[Table 11] Detailed Procedure for SRS antenna switching operation for (R, T) = (2,1), (4,2), and (4,1)

When the UE supports SRS antenna switching, the base station sets SRS-SetUse to 'antenna switching' in the Higer layer parameter setting and UE antenna swithcing is activated, and is set to one of the following three configurations according to the UE capability.

● Config-1: One SRS resource set is composed of two SRS resouces transmitted to different symbols. Each SRS resource is composed of one SRS port.

), 단말이 전송하는 하나의 SRS port index

는 SRS 전송 카운터

에 대해서

로 설정된다.■ Config-1-1: if frequency hopping is disabled (ie,

), One SRS port index transmitted by the UE

SRS transmission counter

about

.

), 단말이 전송하는 하나의 SRS port index

는 SRS 전송 카운터

에 대해서 다음과 같이 설정된다:■ Config-1-2: if frequency hopping is enabled (ie,

), One SRS port index transmitted by the UE

SRS transmission counter

Is set as follows:

,

그리고

,

,

값들은 TS38.211에 정의되어 있다. here

,

And

,

,

The values are defined in TS38.211.

● Config-2: One SRS resource set is composed of two SRS resouces transmitted to different symbols. Each SRS resource is port-paring to two different SRS ports.

), 단말이 전송하는 두개의 안테나 포트 pair index

는 P SRS 전송 카운터

에 대해서

로 설정되며 여기서

이다.■ Config-2-1: when frequency hopping is disabled (ie,

), The two antenna ports transmitted by the terminal pair index

P SRS transmission counter

about

Lt; / RTI >

to be.

), 단말이 전송하는 두개의 안테나 포트 pair index

는 SRS 전송 카운터

에 대해서

로 설정되며 여기서 ■ Config-2-2: when frequency hopping is enabled (ie,

), The two antenna ports transmitted by the terminal pair index

SRS transmission counter

about

Lt; / RTI >

,

그리고

,

,

값들은 TS38.211에 정의되어 있다. Also

,

And

,

,

The values are defined in TS38.211.

● Config-3: One SRS resource set is composed of four SRS resouces transmitted to different symbols. Each SRS resource is composed of one SRS port.

), 단말이 전송하는 하나의 SRS port index

는 SRS 전송 카운터

에 대해서

로 설정된다.■ Config-3-1: when frequency hopping is disabled (ie,

), One SRS port index transmitted by the UE

SRS transmission counter

about

.

), 단말이 전송하는 하나의 SRS port index

는 SRS 전송 카운터

에 대해서 다음과 같이 설정된다:■ Config-3-2: when frequency hopping is enabled (ie,

), One SRS port index transmitted by the UE

SRS transmission counter

Is set as follows:

,

그리고

,

,

값들은 TS38.211에 정의되어 있다.here

,

And

,

,

The values are defined in TS38.211.

When multiple SRS resouces are transmitted in one slot, the guard period required for antenna switching between each SRS resouce is set to Y symbol, and the UE does not transmit another signal during the guard period.

을 설정하는 방법은 상기에 설명한 방법3에 의한 제안이다. 또한 Config-3에서 에서 4Tx 안테나 스위칭을 위해서 선택된 z의 값은 상기에 설명한 방법1과 방법2에 의해 z=16으로 설정되는 것을 제안한다. 표11의 Config-2와 Config-3에서 두 개의 안테나 선택에 대한 포트 pair 인덱스

에 대한 수학식은 및 4Tx 안테나 스위칭을 위한 수식은 NR시스템에서뿐만 아니라 LTE 시스템에서 2Tx (in the case of UE with 2T4R)나 4Tx (in the case of UE with 1T4R)가 지원될 경우에도 사용될 수 있다.More specifically, in Table 11, Config-1, 2 and 3 are respectively 1 Tx (in the case of UE with 1T2R), 2Tx in the case of UE with 2T4R, and 4Tx in the case of UE with 1T4R Indicates the SRS antenna switching setting. As described above, 1Tx (in the case of UE with 1T2R) represents a case where (R, T) = (2,1), 2Tx in the case of UE with 2T4R is (R, T) = , 2), and 4Tx (in the case of UE with 1T4R) represents the case of (R, T) = (4,1). And Config-1-1 indicates that frequency hopping is disabled when (R, T) = (2,1), and Config-1-2 indicates frequency indicates that hopping is enabled. Config-2-1 indicates that frequency hopping is disabled when (R, T) = (4,2) and Config-2-2 indicates frequency hopping when (R, T) = (4,2) Is enabled. Finally, Config-3-1 indicates that frequency hopping is disabled when (R, T) = (4,1), and Config-3-2 indicates that when (R, T) = (4,1) Indicates when frequency hopping is enabled. In Table 11, Config-2 and Config-3 are antenna switching newly introduced in the NR system. In the Config-2, the port pair index

Is proposed by the method 3 described above. We also propose that the value of z selected for 4Tx antenna switching in Config-3 is set to z = 16 by Method 1 and Method 2 described above. The port pair index for the two antenna selections in Config-2 and Config-3 of Table 11

And the formula for 4Tx antenna switching can be used not only in the NR system but also when the 2Tx (in the case of UE with 2T4R) or 4Tx (in the case of UE with 1T4R) is supported in the LTE system.

<Fourth Embodiment>

The fourth embodiment proposes a method of setting the transmission timing when the SRS antenna switching proposed in the third embodiment is applied through the method of the first embodiment. In the first embodiment, when the aperiodic SRS transmission is triggered, a method of setting an SRS triggering offset X in units of slots based on one SRS resource as the transmission time point of the aperiodic SRS has been described. In the third embodiment, And intra- / inter-slot antenna switching may be considered during transmission.

● For aperiodic SRS transmission,

■ Intra-slot antenna switching only

■ Inter-slot antenna switching only

■ Intra + inter-slot antenna switching

A method for determining the transmission timing for intra- / inter-slot antenna switching for aperiodic SRS transmission when the non-periodic SRS transmission is triggered and the transmission time point of the aperiodic SRS is set based on one SRS resource 5. 5 illustrates an example in which an aperiodic SRS is transmitted at n + X through the setting of aperiodic SRS triggering offset X, assuming that triggering for aperiodic SRS occurs in slot n.

Priority e10 shows a method for setting the transmission timing of an aperiodic SRS transmission in case of performing intra-slot antenna switching for aperiodic SRS transmission. For the intra-slot antenna switching, the aperiodic SRS transmission timing should be set so that all the SRS resources set for antenna switching are transmitted in one slot, and when the aperiodic SRS triggering offset X is set based on one SRS resource, By setting the aperiodic SRS triggering offset X value for all the SRS resources set for switching to be the same, antenna switching can be performed in one slot as shown in e10.

Next, e20 shows a method of setting the transmission timing of the aperiodic SRS transmission in the case of inter-slot antenna switching for aperiodic SRS transmission. For inter-slot antenna switching, it is necessary to set the non-periodic SRS transmission timing such that the SRS resources set for antenna switching are transmitted to different slots, and when the non-periodic SRS triggering offset X is set based on one SRS resource, It is possible to set an SRS triggering offset X value for the SRS resource set for SRS resource to be different for the SRS resource so that the antenna switching can be performed between the other slots as shown in e20. For example, if the non-periodic SRS triggering offset X _A = 0 for SRS resource A and the non-periodic SRS triggering offset X _B = 1 for SRS resource B are set to 1 in e20, inter-slot antenna switching .

Finally, e30 shows a method of setting the transmission timing of the aperiodic SRS transmission in the case of Intra + inter-slot antenna switching for aperiodic SRS transmission. For Intra + inter-slot antenna switching, the non-periodic SRS transmission timing should be set so that two or more of the SRS resources set for antenna switching are transmitted in one slot and at least one of the other SRS resources is transmitted to the other slot. When the periodic SRS triggering offset X is set based on one SRS resource, the non-periodic SRS triggering offset X value for the SRS resource set for antenna switching is set differently for the SRS resource, Antenna switching can occur. For example, in FIG. 30, when four SRS resources are set for antenna switching, two of the SRS resources are set to be transmitted to one slot and the other two to be transmitted to another slot. Specifically, when the set triggering aperiodic SRS offset X _B SRS resource for C and D by an aperiodic SRS triggering offset X _A for SRS resource A and B will occur is Intra + inter-slot antenna switching.

<Fifth Embodiment>

The fifth embodiment proposes a method of setting the transmission timing when the SRS antenna switching proposed in the third embodiment is applied through the method of the second embodiment. In the second embodiment, a method of setting an SRS triggering offset X in units of slots based on one SRS resource set when a non-periodic SRS transmission is triggered is described. In the third exemplary embodiment, It has been demonstrated that intra- / inter-slot antenna switching can be considered for SRS transmission.

● For aperiodic SRS transmission,

■ Intra-slot antenna switching only

■ Inter-slot antenna switching only

■ Intra + inter-slot antenna switching

A method of determining the transmission timing for intra- / inter-slot antenna switching for aperiodic SRS transmission when the aperiodic SRS transmission is triggered and the transmission time of the aperiodic SRS is set based on one SRS resource set This will be described in more detail with reference to FIG.

FIG. 6 is a diagram illustrating an example of determining the timing at which an aperiodic SRS is transmitted through the setting of aperiodic SRS triggering offset X, assuming that triggering for aperiodic SRS occurs in slot n.

Priority f 10 shows a method for setting the transmission timing of the aperiodic SRS transmission in the case of intra-slot antenna switching for aperiodic SRS transmission. For intra-slot antenna switching, non-periodic SRS transmission timing should be set so that all SRS resources set for antenna switching are transmitted in one slot, and when non-periodic SRS triggering offset X is set based on one SRS resource set Since there is only one SRS resource set that can be set for antenna switching, an intra-slot antenna switching operation is automatically performed. As shown in Figure 10, the aperiodic SRS triggering offset X for the SRS resource set is set in one slot, and the aperiodic SRS is transmitted at n + X.

Next, f20 shows a method of setting the transmission timing of the aperiodic SRS transmission in the case of inter-slot antenna switching for aperiodic SRS transmission. For inter-slot antenna switching, non-periodic SRS transmission timing should be set so that SRS resources set for antenna switching are transmitted to different slots, and when non-periodic SRS triggering offset X is set based on one SRS resource set, Inter A separate base station setup is needed for -slot antenna switching. In the present invention, when the aperiodic SRS triggering offset X is set based on one SRS resource set in the RRC and the mode setting for the intra- / inter-slot antenna switching is selected as the inter-slot antenna switching, A method for determining the transmission time point is proposed as follows.

● For aperiodic SRS transmission and inter-slot antenna switching only, if aperiodic SRS triggering offset X is configured by RRC on a per-

■ The first SRS resource follows aperiodic SRS triggering offset X

■ The second SRS resource follows aperiodic SRS triggering offset X + 1, implicitly

■ If there is third and fourth SRS resources are exist

◆ The third SRS resource follows aperiodic SRS triggering offset X + 2, implicitly

◆ The fourth SRS resource follows aperiodic SRS triggering offset X + 3, implicitly

In Fig. 20, an example is shown through the above principle when two SRS resources are set for antenna switching. In Figure 20, SRS resource A follows the aperiodic SRS triggering offset X set for the SRS resource set, and SRS resource B is automatically set to SRS triggering offset X + 1. Inter-slot antenna switching occurs in successive slots using this method.

Finally, FIG. 30 shows a method of setting the transmission timing of the aperiodic SRS transmission in the case of Intra + inter-slot antenna switching for aperiodic SRS transmission. For Intra + inter-slot antenna switching, the non-periodic SRS transmission timing should be set so that two or more of the SRS resources set for antenna switching are transmitted in one slot and at least one of the other SRS resources is transmitted to the other slot. If periodic SRS triggering offset X is set based on one SRS resource set, a separate base station setup is required for Intra + inter-slot antenna switching. In the present invention, when the aperiodic SRS triggering offset X is set based on one SRS resource set in the RRC and the mode setting for the intra- / inter-slot antenna switching is selected as Intra + inter-slot antenna switching, A method of determining the transmission time point of the SRS is proposed as follows.

● For aperiodic SRS transmission and Intra + inter-slot antenna switching, if aperiodic SRS triggering offset X is configured by RRC on a per-

■ The first and second SRS resources follows aperiodic SRS triggering offset X

■ The third and fourth SRS resources follows aperiodic SRS triggering offset X + 1, implicitly

In Fig. 30, an example is shown through the above principle when four SRS resources are set for antenna switching. In Figure 30, SRS resources A and B follow the aperiodic SRS triggering offset X set for the SRS resource set, and the SRS resources C and D are automatically set to the SRS triggering offset X + 1. Intra + inter-slot antenna switching occurs in consecutive slots using this method. In case of Intra + inter-slot in the aspect of implementation, it may be limited to the case where switching is performed in intra-slot by two when four SRS resources are set as described above. However, if four SRS resources are set using a method similar to the above, one SRS resource is transmitted in one slot and the remaining three SRS resources are transmitted in the other slot. For non-periodic SRS for Intra + inter- The timing can be set by the base station in the RRC in a similar manner. In the fifth embodiment, when a non-periodic SRS transmission of the second exemplary embodiment is triggered, a method of setting an SRS triggering offset X in units of slots on the basis of one SRS resource set as a transmission time point of an aperiodic SRS SRS triggering offset is implicitly applied to SRS resource. Although SRS triggering offsets are implicitly applied to different SRS resources in the above description, the present invention is applicable to beam management and other SRS applications. Also, according to the description of the embodiment, for the four SRS resources set when SRS triggering offsets are implicitly applied to different SRS resources, the first SRS resource follows the SRS triggering offset X set based on the SRS resource set, and the second SRS resource , The SRS triggering offset X + 1 for the third SRS resource, the SRS triggering offset X + 2 for the third SRS resource, and the SRS triggering offset X + 3 for the fourth SRS resource. Lt; / RTI &gt; In the above, a method of setting an SRS triggering offset X on a per-slot basis based on one SRS resource set as a transmission point of an aperiodic SRS is proposed in which a SRS triggering offset is implicitly applied to different SRS resources when necessary However, since an SRS resource is mapped to different antenna ports in an antenna switching operation, a method of implicitly applying an SRS triggering offset based on an antenna port can also be considered. For example, in an antenna switching of 1T2R or 1T4R, since different SRS ports are mapped to different SRS resources, an SRS triggering offset value K can be implicitly set for an SRS port. In an antenna switching of 2T4R, Since an SRS port pair composed of two different antennas is mapped, an SRS triggering offset value K can be implicitly set for an SRS port pair.

<Sixth Embodiment>

The sixth embodiment specifically describes the base station setting and the terminal operation for the timing of the aperiodic SRS transmission together with the antenna switching operation described in the fourth embodiment and the fifth embodiment through the sequence flow chart.

FIG. 7 is a diagram illustrating an order flow between base station units for timing of aperiodic SRS transmission together with an antenna switching operation. FIG. First, the UE transmits UE capability for antenna switching to the BS. Specifically, during the SRS antenna switching for 1Tx (in the case of UE with 1T2R), 2Tx in the case of UE with 2T4R, and 4Tx in the case of UE with 1T4R, To the base station. The base station receiving this information transmits relevant SRS information to the mobile station so that the mobile station can perform antenna switching. Table 6 and Table 7 are used to refer to the RRC information set in the SRS resource and the SRS resource set. One SRS resource set is set in consideration of antenna switching and information about the related SRS resource is set in the RRC. Next, for the aperiodic SRS transmission, the base station performs Aperiodic SRS triggering through DCI. Then, the UE transmits the Aperiodic SRS at a predetermined point by referring to the Aperiodic SRS triggering offset information set in the RRC.

8 is a view showing the operation of the base station side for timing setting in the aperiodic SRS transmission together with the antenna switching operation. In step h10, the BS selects an SRS antenna switching mode from the UE capability received from the UE. In step h20, related RRC information is set so that the UE can perform SRS antenna switching. As described in the fifth embodiment, when aperiodic SRS transmission is triggered, when the aperiodic SRS triggering offset X is set based on one SRS resource set, the operation of inter-slot antenna switching and inter-slot antenna switching is set Lt; / RTI &gt; field may be added. Table 12 below shows an example of setting the antenna switching mode in the SRS resource configuration.

[Table 12] How the offset value for non-periodic SRS triggering is set based on one SRS resource

In the Antenna Switching Mode of Table 12, IntraOnly represents a case in which Intra-slot antenna switching only operates, IntraOnly denotes a case in which Intra-slot antenna switching only operates, and InterIntra denotes a case in which Intra + inter-slot antenna switching operates. As described in the third embodiment, the setting can be set according to a transmission method such as periodic, semi-persistent, and aperiodic, and can be periodically, semi-periodically, Depending on the mode, some antenna switching may be limited. Also, in the case of Intra + inter-slot antenna switching, as described in the fifth embodiment, it is possible to set various methods according to need, or to set only one case. Next, the base station triggers the aperiodic SRS through the DCI at step h30 and finally receives the aperiodic SRS from the terminal at step h40.

9 is a diagram illustrating terminal side operation for setting timing for aperiodic SRS transmission together with antenna switching operation. In step i10, the UE transmits the UE capability for SRS antenna switching to the BS. Next, in step i20, the SRS related RRC information set by the station is received. At this time, the SRS-related RRC information also includes setting information for antenna switching. Next, in step i30, the UE recognizes that the aperiodic SRS is triggered through the DCI. In step i40, the Aperiodic SRS is transmitted to the base station at a predetermined time from the Aperiodic SRS triggering offset information set in the RRC.

<Seventh Embodiment>

The seventh embodiment proposes a further invention in case SRS antenna switching is supported for aperiodic SRS transmission. FIG. 10 is a diagram illustrating another example of supporting SRS antenna switching for aperiodic SRS transmission. As described above, it is possible to perform antenna switching for the aperiodic SRS transmission in the following manner.

● For aperiodic SRS transmission,

■ Method 1: Intra-slot antenna switching only

■ Method 2: Inter-slot antenna switching only

■ Method 3: Intra + inter-slot antenna switching

Also, various methods for supporting the antenna switching for aperiodic SRS transmission have been proposed through the fourth and fifth embodiments. The antenna switching operation principle for 1T2R, 2T4R, and 1T4R is described in detail in the third embodiment. In case of 1T2R and 2T4R antenna switching, two SRS resources should be set and in case of 1T4R antenna switching, four SRS resources should be set. Therefore, in the aperiodic SRS transmission, in the case of 1T2R and 2T4R antenna switching, four SRS resources are transmitted in one slot in the case of 1T4R antenna switching, compared to the method 1 in which two SRS resources are transmitted in one slot. Applying the above-mentioned method 1 for transmitting may have a considerable burden on the use of resources. Specifically, in order to apply the method 1 in the case of 1T4R antenna switching, at least 7 symbols are required. Alternatively, three symbols may be supported in the case of 1T2R, 2T4R antenna switching. For the sake of convenience of operation, as shown in FIG. 10, if the setting of antenna switching is set to 1T2R and 2T4R when transmitting aperiodic SRS in j10 step, it moves to step j20 and supports only method 1. If it is set to 1T4R, We propose a support method that supports only Method 2 or 3.

&Lt; Eighth Embodiment >

The eighth embodiment proposes a solution to the inconsistency in semi-static slot format information (SFI) and dynamically set slot format information. Specifically, a solution will be described as an example of SRS transmission focusing on the present invention. Before describing the contents of the invention, the information setting and signaling method for the slot format will be described. One slot in the normal cyclic prefix (CP) is composed of 14 OFDM symbols. Each symbol is represented by Downlink (denoted by 'D'), flexible (denoted by 'X') and Uplink (denoted by 'U' Can be set. Here, flexible can be configured as downlink or uplink, and it is also possible to leave it not set as downlink or uplink. Below is a summary of how slot format information is set up.

&Lt; Setting and Signaling Method of Information on Slot Format >

■ SIB (System Information Bit) to configure the cell common slot format information Downlink / Uplink / flexible setup and signaling

■ RRC allows UE-specific setting and signaling of the slot format for flexible (can be set to Downlink, Uplink or Flexible)

■ If the base station is set to dynamically change the slot format information, you can set and signal the slot format for flexible via Group common DCI (flexible can be set to Downlink, Uplink or Flexible)

As described above, since the setting of the slot format can be changed dynamically through the DCI, a problem may occur when the downlink or uplink transmission area to be transmitted is not guaranteed. For example, when the aperiodic SRS transmission is triggered in the second embodiment, a method of setting an SRS triggering offset X in units of slots based on one SRS resource set is proposed in the transmission time point of the aperiodic SRS. In the example, a method for determining transmission timing for intra- / inter-slot antenna switching for aperiodic SRS transmission has been described. In the sixth embodiment, the setting for intra- / inter-slot antenna switching for aperiodic SRS transmissions The method comprising this RRC has been described. In this case, when the aperiodic SRS transmission is set through the RRC, the SRS is transmitted to the area set as the uplink in the slot, but if the slot format is changed dynamically, the SRS may not be transmitted. This problem has the same issue in periodic and semi-periodic SRS transmissions as well as in aperiodic SRS transmissions. In the case of periodic and semi-periodic SRS transmissions, the cycle and slot offset value for SRS transmission are set through the RRC. However, there is the same problem when the slot format is changed dynamically in intra- / inter-slot transmission . Therefore, although the description of the following embodiments focuses on the aperiodic SRS, the method proposed in the eighth embodiment is a method in which information on semi-static slot format information and dynamically set slot format information Note that it can be applied in all cases where a downlink or uplink transmission area is not guaranteed. First, an example of a case where a problem occurs will be described with reference to FIG. The slot transmission timing of FIG. 14 will be described in detail with reference to the above description of the embodiment. In FIG. 13, k10 shows a case where four SRS resources are transmitted in different slots. At this time, the slot format for the area for transmitting SRS in the second, third, and fourth slots by the DCI is changed to DL, A case where a problem occurs is shown. Similarly, in FIG. 13, k11 shows a case where two SRS resources among four SRS resources are transmitted in different slots. At this time, the slot format for the SRS transmission region in the second slot is changed to DL by the DCI, And shows a case where a problem occurs in transmission. As shown in the example of FIG. 13, the transmission of the SRS should be transmitted in the symbol region set to the UL in the slot format, but the slot format for the symbol is changed to the DL, so that the SRS transmission can not be performed.

In order to solve such a problem, the following three methods are proposed. As a concrete example, as shown in FIG. 14, when the SRS transmission area is not guaranteed in the aperiodic SRS transmission, the first method that can solve this problem is as follows.

■ Method 1: Following the information on the semi-static slot format, the base station does not change the slot format dynamically.

The method 1 can be interpreted as expecting that the terminal does not change the slot format for the SRS transmission. Alternatively, the MS may be interpreted to ignore the slot format information dynamically set for the SRS transmission and give priority to the semi-static slot format information. An example of Method 1 will be described in more detail with reference to FIG. 14 shows a case where two SRS resources among four SRS resources are transmitted to different slots, and the UL setting is always ensured for the SRS transmission region by the method 1 in FIG. Alternatively, Method 2 can be considered as follows.

■ Method 2: Allow the base station to change the slot format dynamically, dropping the transmission in all cases where downlink or uplink transmission area is not guaranteed.

The method 2 can be interpreted that the terminal does not transmit the SRS when the slot format is changed and the SRS transmission can not be performed. An example of Method 1 will be described in more detail with reference to FIG. 14 illustrates a case where two SRS resources among four SRS resources are transmitted in different slots. In method 2, if the slot format is changed in the second slot and SRS transmission can not be performed, SRS transmission is not performed Drop the transmission. Finally, Method 3 can be considered as follows.

■ Method 3: The base station allows the slot format to be changed dynamically, thus delaying the transmission in all cases where the downlink or uplink transmission area is not guaranteed. And performs the transmission in the area where the next uplink or uplink transmission area is guaranteed.

If the SRS transmission is not possible due to the change of the slot format, the method 3 can be interpreted that the SRS transmission is delayed and the UL transmission is performed when the latest UL area is allocated. An example of Method 1 will be described in more detail with reference to FIG. 14, l30 shows a case where two SRS resources among four SRS resources are transmitted in different slots. In the case where SRS transmission is impossible because the SRS transmission region is set to DL in the second slot, the SRS transmission region Is set to UL, the SRS transmission is performed according to the method 3. In FIG. 14, l40 shows a case where two SRS resources among four SRS resources are transmitted in different slots. In the second slot, a part of the SRS transmission region is set to UL and a part of the SRS transmission region is set to DL, In this case, the dual transmittable part performs transmission in the second slot and the non-transmittable SRS performs the SRS transmission according to the method 3 when the SRS transmission area is set to UL after the Y slot. In addition, it is possible to consider dropping the SRS transmission by the method 2 if the threshold value is set in the method 3 and the threshold value is exceeded. Specifically, it is possible to introduce a method of dropping the SRS transmission when the threshold value is set in the Y-slot unit and Y exceeds 5.

In order to perform the above-described embodiments of the present invention, the transmitter, receiver and processing unit of the terminal and the base station are shown in FIGS. 11 and 12, respectively. A timing setting method for aperiodic SRS transmission from the first to sixth embodiments is shown. To perform this, a base station and a receiving unit, a processing unit, and a transmitting unit of the UE must operate according to the embodiments, respectively.

11 is a block diagram illustrating an internal structure of a terminal according to an embodiment of the present invention. 11, the terminal of the present invention may include a terminal receiving unit 1800, a terminal transmitting unit 1804, and a terminal processing unit 1802. [ The terminal receiving unit 1800 and the terminal may be collectively referred to as a transmitting unit 1804 in the embodiment of the present invention. The transmitting and receiving unit can transmit and receive signals to and from the base station. The signal may include control information and data. To this end, the transmitting and receiving unit may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, an RF receiver for low-noise amplifying the received signal and down-converting the frequency. The transceiving unit may receive a signal through a wireless channel, output the signal to the terminal processing unit 1802, and transmit the signal output from the terminal processing unit 1802 through a wireless channel. The terminal processor 1802 may control a series of processes so that the terminal can operate according to the embodiment of the present invention described above. For example, the terminal processor 1802 may transmit an aperiodic SRS signal from the terminal transmitter 1804 to the base station based on the aperiodic SRS transmission timing set by the base station.

12 is a block diagram showing an internal structure of a base station according to an embodiment of the present invention. 12, the base station of the present invention may include a base station receiving unit 1901, a base station transmitting unit 1905, and a base station processing unit 1903. The base station receiving unit 1901 and the base station transmitting unit 1905 may be collectively referred to as a transmitting / receiving unit in the embodiment of the present invention. The transmitting and receiving unit can transmit and receive signals to and from the terminal. The signal may include control information and data. To this end, the transmitting and receiving unit may include an RF transmitter for up-converting and amplifying the frequency of a transmitted signal, an RF receiver for low-noise amplifying the received signal and down-converting the frequency. The transceiving unit may receive a signal through a wireless channel, output the signal to the base station processing unit 1903, and transmit the signal output from the terminal processing unit 1903 through a wireless channel. The base station processor 1903 can control a series of processes so that the base station can operate according to the above-described embodiment of the present invention. For example, the base station receiver 1901 may receive a signal transmitted by the terminal, and the base station processor 1903 may set a timing for an aperiodic SRS transmission and process the received signal. In addition, the base station transmitter 1905 may transmit timing information for aperiodic SRS transmission and a signal for triggering aperiodic SRS.

It should be noted that the embodiments of the present invention disclosed in the present specification and drawings are only illustrative of the present invention in order to facilitate the understanding of the present invention and are not intended to limit the scope of the present invention. That is, it will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention are possible. Further, each of the above embodiments can be combined with each other as needed. For example, all of the embodiments of the present invention can be combined with each other to operate a base station and a terminal.

Claims (1)

A method for processing a control signal in a wireless communication system,
Receiving a first control signal transmitted from a base station;
Processing the received first control signal; And
And transmitting the second control signal generated based on the process to the base station.

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