KR20210059559A - Method and apparatus for generation of srs(sounding reference signal) sequence for 5g nr(new radio) - Google Patents

Abstract

The present invention provides a method and an apparatus for configuring a sounding reference signal (SRS) sequence for a terminal performing 5G new radio (NR) communication in a wireless communication system. A method for transmitting an SRS by a terminal comprises the steps of: receiving, by the terminal, SRS sequence-related information including an SRS ID value from a base station; calculating, by the terminal, a root index q value on the basis of information received from the base station; generating, by the terminal, a base sequence from the root index q and applying a cyclic shift (CS) value to the same to generate an SRS sequence; and transmitting, by the terminal, the SRS sequence to the base station by mapping the generated SRS sequence to time-frequency resources. A case in which the SRS ID value is less than 1024 and a case in which the SRS ID value is 1024 or more are distinguished to calculate the root index q differently.

Description

SRS sequence generation method and apparatus for 5G NR {METHOD AND APPARATUS FOR GENERATION OF SRS(SOUNDING REFERENCE SIGNAL) SEQUENCE FOR 5G NR(NEW RADIO)}

The present invention relates to a method and apparatus for configuring a reference signal (RS) sequence in a wireless communication system. Specifically, the present invention relates to a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence for a terminal performing 5G NR (New Radio) communication.

ITU (International Telecommunication Union) is developing IMT (International Mobile Telecommunication) framework and standards, and recently, discussion for 5G (5G) communication is underway through a program called "IMT for 2020 and beyond". .

In order to meet the requirements presented in "IMT for 2020 and beyond", the 3GPP (3rd Generation Partnership Project) NR (New Radio) system takes into account various scenarios, service requirements, potential system compatibility, etc. It is being discussed in the direction of supporting various numerology on the basis of resource units.

In addition, discussions are underway to support Multiple Input Multiple Output (MIMO) in NR, and a method for efficiently generating a sequence of SRS (Sounding Reference Signal) used to measure an uplink channel in NR MIMO is needed. I can. In the following, a method of constructing a base sequence of an SRS sequence in order to efficiently generate an SRS sequence will be described.

The present invention can provide a method and apparatus for configuring a Sounding Reference Signal (SRS) in a wireless communication system.

An object of the present invention is to provide a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence for a terminal performing 5G New Radio (NR) communication in a wireless communication system.

An object of the present invention is to provide a method and apparatus for transmitting a sounding reference signal (SRS) configured by a terminal performing 5G New Radio (NR) communication in a wireless communication system, receiving it by a base station, and measuring a channel state. .

An object of the present invention is to provide a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence capable of having a larger number of base sequences in a wireless communication system.

An object of the present invention is to provide a method and apparatus for configuring an SRS sequence capable of maximally reducing interference between a plurality of sounding reference signals (SRSs) in a wireless communication system.

Other objects and advantages of the present invention can be understood by the following description, and will be more clearly understood by examples of the present invention. In addition, it will be easily understood that the objects and advantages of the present invention can be realized by the means shown in the claims and combinations thereof.

The present invention can provide a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence for a terminal performing 5G New Radio (NR) communication in a wireless communication system. In this case, in a method for transmitting a sounding reference signal (SRS) by the terminal, the terminal receiving SRS sequence-related information including an SRS ID value from a base station, and the terminal is routed based on the information received from the base station. Calculating an index q value, the terminal generating a base sequence from the root index q and applying a cyclic shift (CS) value thereto to generate an SRS sequence, and the terminal generating the generated SRS sequence at a time-frequency It may include the step of transmitting the SRS to the base station by mapping to a resource.

In this case, the root index q may be calculated differently by distinguishing between the case where the SRS ID value is less than 1024 and the case where the SRS ID value is 1024 or more.

Features briefly summarized above with respect to the present invention are merely exemplary aspects of the detailed description of the present disclosure to be described later, and do not limit the scope of the present disclosure.

According to an embodiment of the present invention, a method and apparatus for configuring a Sounding Reference Signal (SRS) in a wireless communication system can be provided.

According to an embodiment of the present invention, a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence for a terminal performing 5G New Radio (NR) communication in a wireless communication system can be provided.

According to an embodiment of the present invention, a terminal performing 5G NR (New Radio) communication in a wireless communication system transmits a configured SRS (Sounding Reference Signal), receives it, and provides a method and an apparatus for measuring a channel state. can do.

According to an embodiment of the present invention, it is possible to provide a method and apparatus for configuring a Sounding Reference Signal (SRS) sequence capable of having a greater number of base sequences in a wireless communication system.

According to an embodiment of the present invention, it is possible to provide a method and apparatus for configuring an SRS sequence capable of maximally reducing interference between a plurality of sounding reference signals (SRSs) in a wireless communication system.

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

1 is a diagram showing a frame structure for downlink/uplink transmission according to an embodiment of the present invention.
2 is a diagram illustrating a resource grid and a resource block according to an embodiment of the present invention.
3 is a diagram illustrating a method of configuring a root index value for an SRS sequence according to an embodiment of the present invention.
4 is a diagram showing the operation of a base station and a terminal according to an embodiment of the present invention.
5 is a diagram showing the configuration of a base station apparatus and a terminal apparatus according to an embodiment of the present invention.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the accompanying drawings so that those of ordinary skill in the art may easily implement the embodiments. However, the present disclosure may be implemented in various different forms and is not limited to the embodiments described herein.

In describing an embodiment of the present disclosure, when it is determined that a detailed description of a known configuration or function may obscure the subject matter of the present disclosure, a detailed description thereof will be omitted. In addition, parts not related to the description of the present disclosure in the drawings are omitted, and similar reference numerals are attached to similar parts.

In the present disclosure, when a component is said to be "connected", "coupled" or "connected" with another component, it is not only a direct connection relationship, but also an indirect connection relationship in which another component exists in the middle. It can also include. In addition, when a certain component "includes" or "have" another component, it means that other components may be further included rather than excluding other components unless otherwise stated. .

In the present disclosure, terms such as first and second are used only for the purpose of distinguishing one component from other components, and do not limit the order or importance of the components unless otherwise noted. Accordingly, within the scope of the present disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment is referred to as a first component in another embodiment. It can also be called.

In the present disclosure, components that are distinguished from each other are intended to clearly describe each feature, and do not necessarily mean that the components are separated. That is, a plurality of components may be integrated into one hardware or software unit, or one component may be distributed to form a plurality of hardware or software units. Therefore, even if not stated otherwise, such integrated or distributed embodiments are also included in the scope of the present disclosure.

In the present disclosure, components described in various embodiments do not necessarily mean essential components, and some may be optional components. Accordingly, an embodiment consisting of a subset of components described in an embodiment is also included in the scope of the present disclosure. In addition, embodiments including other elements in addition to the elements described in the various embodiments are included in the scope of the present disclosure.

In addition, this specification describes a wireless communication network, and operations performed in the wireless communication network are performed in the process of controlling the network and transmitting data in a system (for example, a base station) in charge of the wireless communication network, or The work can be done at a terminal coupled to the network.

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

In the present disclosure, transmitting or receiving a channel includes transmitting or receiving information or signals through the corresponding channel. For example, transmitting the control channel means transmitting control information or signals through the control channel. Similarly, transmitting a data channel means transmitting data information or signals through the data channel.

In the following description, the term NR (New Radio) system is used for the purpose of distinguishing a system to which various examples of the present disclosure are applied from an existing system, but the scope of the present disclosure is not limited by these terms. .

For example, the NR system supports various subcarrier spacing (SCS) in consideration of various scenarios, service requirements, and potential system compatibility. In addition, the NR system has multiple channels to overcome unfavorable channel environments such as high path-loss, phase-noise, and frequency offset occurring on a high carrier frequency. It is possible to support transmission of a physical signal/channel through a beam of. Through this, the NR system can support applications such as enhanced Mobile Broadband (eMBB), Massive Machine Type Communications (mMTC)/ultra Machine Type Communications (uMTC), and Ultra Reliable and Low Latency Communications (URLLC). However, in the present specification, the term NR system is used as an example of a wireless communication system, but the term NR system itself is not limited to the above-described features.

In addition, as an example, 5G mobile communication technology may be defined. In this case, as an example, the 5G mobile communication technology may be defined to include not only the NR system described above, but also an existing Long Term Evolution-Advanced (LTE-A) system. That is, 5G mobile communication may be a technology that operates in consideration of not only the newly defined NR system but also backward compatibility with the previous system.

For example, the 5G Multiple Input Multiple Output (MIMO) field may include both MIMO in LTE system and MIMO technology in NR system. In this case, the MIMO field may be an essential field for improving performance in 5G and integrating a variety of new services.

In the following, for convenience of description, operation and related information for a reference signal (RS) used in MIMO based on the NR system will be described. However, the following features may not be limited to a specific system, and may be equally applied to other systems implemented similarly, and are not limited to the above-described embodiments.

The NR system is described below. As an example, FIGS. 1 and 2 are diagrams illustrating a frame structure and a resource block for an NR system according to an embodiment of the present invention.

1 is a diagram showing an NR frame structure and a numerology according to an embodiment of the present invention.

일 수 있다. 이때,

이고,

일 수 있다. 또한,

는 NR 시간 단위와 LTE 시간 단위와의 배수 관계에 대한 상수일 수 있다. The basic unit of time domain in NR is

Can be At this time,

ego,

Can be Also,

May be a constant for a multiple relationship between the NR time unit and the LTE time unit.

,

및

가 정의될 수 있다.As a reference time unit, in LTE

,

And

Can be defined.

Frame structure

를 가질 수 있다. 이 때, 하나의 프레임은

시간에 해당하는 10개의 서브프레임으로 구성된다. 서브프레임마다 연속적인 OFDM 심볼의 수는

일 수 있다. 또한, 각 프레임은 2개의 하프 프레임(half frame)으로 나누어지며, 하프 프레임은 0~4 서브프레임과 5~9 서브프레임으로 구성될 수 있다. 이때, 하프 프레임 1 (half frame 1)은 0~4 서브프레임으로 구성되고, 하프 프레임 2(half frame 2)는 5~9 서브프레임으로 구성될 수 있다. 1, the time structure of a frame for downlink and uplink (Downlink/Uplink, DL/UL) transmission is

Can have. At this time, one frame

It consists of 10 subframes corresponding to time. The number of consecutive OFDM symbols per subframe is

Can be In addition, each frame is divided into two half frames, and the half frame may be composed of 0 to 4 subframes and 5 to 9 subframes. At this time, half frame 1 may be composed of 0 to 4 subframes, and half frame 2 may be composed of 5 to 9 subframes.

In this case, the transmission timing of the uplink transmission frame i is determined based on the downlink reception timing in the terminal based on Equation 1 below.

은 듀플렉스 모드(duplex mode) 차이 등으로 발생하는 TA 오프셋(TA offset) 값일 수 있다. 기본적으로 FDD(Frequency Division Duplex)에서

은 0을 가지지만 TDD(Time Division Duplex)에서는 DL-UL 스위칭 시간에 대한 마진을 고려해서

고정된 값으로 정의될 수 있다.In Equation 1 below

May be a TA offset value generated due to a difference in duplex mode or the like. Basically in FDD (Frequency Division Duplex)

Has 0, but in TDD (Time Division Duplex), considering the margin for the DL-UL switching time

It can be defined as a fixed value.

[Equation 1]

2 is a diagram illustrating a resource grid and a resource block.

Referring to FIG. 2, a resource element in a resource grid may be indexed according to each subcarrier spacing (SCS). In this case, one resource grid may be generated for each antenna port and for each subcarrier spacing. Uplink and downlink transmission and reception may be performed based on the corresponding resource grid.

)를 구성할 수 있다. 자원 블록에 대한 인덱스는 특정 주파수 대역 또는 시스템 대역폭 내에서 활용될 수 있다.One resource block is composed of 12 resource elements in the frequency domain, and an index for one resource block per 12 resource elements as shown in Equation 2 below (

) Can be configured. The index for the resource block may be utilized within a specific frequency band or system bandwidth.

[Equation 2]

Numerologies

Numerology can be configured in various ways to satisfy the various services and requirements of the NR system. For example, unlike the existing LTE/LTE-A system supporting one subcarrier spacing (SCS), a plurality of SCSs may be supported.

A new neurology for NR systems that includes supporting multiple SCSs is 3GHz or less to solve the problem of not being able to use a wide bandwidth in the existing frequency range such as 700MHz or 2GHz or a carrier. , 3GHz~6GHz or 6GHZ~52.6GHz can operate in the same frequency range or carrier. However, the scope of the present disclosure is not limited thereto.

As an example, referring to Table 1 below, the numanology may be defined based on subcarrier spacing (SCS), CP length, and the number of OFDM symbols per slot used in an Orthogonal Frequency Division Multiplexing (OFDM) system. have. The above-described values may be provided to the terminal through higher layer parameters DL-BWP-mu and DL-BWP-cp (DL) and UL-BWP-mu and UL-BWP-cp (UL).

가 2인 경우로서 서브캐리어 스페이싱이 60kHz인 경우에서 일반 CP(Normal CP) 및 확장 CP(Extended CP)가 적용될 수 있으며, 다른 대역에서는 일반 CP만 적용될 수 있다.In addition, as an example, in Table 1 below

When is 2, when subcarrier spacing is 60 kHz, normal CP (CP) and extended CP (Extended CP) may be applied, and only normal CP may be applied in other bands.

[Table 1]

In this case, a normal slot may be defined as a basic time unit used to transmit one data and control information basically in the NR system. The length of a general slot may basically consist of the number of 14 OFDM symbols. Also, unlike a slot, a subframe has an absolute time length corresponding to 1 ms in the NR system and can be used as a reference time for the length of another time period. In this case, for coexistence or backward compatibility of LTE and NR systems, a time interval such as an LTE subframe may be required in the NR standard.

For example, in LTE, data may be transmitted based on a transmission time interval (TTI), which is a unit time, and the TTI may be configured in units of one or more subframes. In this case, even in LTE, one subframe may be set to 1 ms, and 14 OFDM symbols (or 12 OFDM symbols) may be included.

In addition, a non-slot may be defined in NR. The non-slot may mean a slot having a number smaller than a normal slot by at least one symbol. For example, in the case of providing a low delay time such as an Ultra-Reliable and Low Latency Communications (URLLC) service, the delay time may be reduced through a non-slot having a smaller number of symbols than a normal slot. In this case, the number of OFDM symbols included in the non-slot may be determined in consideration of the frequency range. For example, in a frequency range of 6 GHz or higher, a non-slot having a length of 1 OFDM symbol may be considered. As another example, the number of OFDM symbols defining a non-slot may include at least two OFDM symbols. In this case, the range of the number of OFDM symbols included in the non-slot may be configured as a mini-slot length up to (general slot length) -1. However, as a non-slot standard, the number of OFDM symbols may be limited to 2, 4, or 7 symbols, but is not limited to the above-described embodiment.

가 1 및 2에 해당하는 서브캐리어 스페이싱이 사용되고, 6GHz 초과의 비면허 대역에서는

에서는 3 및 4에 해당하는 서브캐리어 스페이싱이 사용될 수 있다.In addition, as an example, in the unlicensed band below 6GHz

Subcarrier spacing corresponding to 1 and 2 is used, and in the unlicensed band exceeding 6 GHz,

In the subcarrier spacing corresponding to 3 and 4 may be used.

슬롯 당 OFDM 심볼의 수

를 나타낸다. 표 2는 표 1에서 제공하는 바와 같이 각 서브캐리어 스페이싱 값에 따른 슬롯 당 OFDM 심볼의 수, 프레임 당 슬롯의 수 및 서브프레임 당 슬롯의 수를 나타낸다. 이때, 표 2에서는 14개의 OFDM 심볼을 갖는 일반 슬롯을 기준으로 상술한 값들을 나타낸다.In addition, Table 2 shows for each subcarrier spacing setting in the case of a general CP.

Number of OFDM symbols per slot

Represents. Table 2 shows the number of OFDM symbols per slot, the number of slots per frame, and the number of slots per subframe according to each subcarrier spacing value, as provided in Table 1. In this case, Table 2 shows the above-described values based on a general slot having 14 OFDM symbols.

[Table 2]

가 2인 경우로서 서브캐리어 스페이싱이 60kHz일 때 확장 CP가 적용될 수 있다. 표 3은 확장 CP인 경우로서

슬롯 당 OFDM 심볼의 수

는 12인 일반 슬롯을 기준으로 각각의 값을 나타낼 수 있다. 이때, 표 3을 참조하면, 60kHz 서브캐리어 스페이싱을 따르는 확장 CP인 경우, 슬롯 당 심볼의 수, 프레임 당 슬롯의 수 및 서브프레임당 슬롯의 수를 나타낼 수 있다.In addition, as described above,

When is 2 and the subcarrier spacing is 60 kHz, the extended CP may be applied. Table 3 is a case of extended CP

Number of OFDM symbols per slot

May represent each value based on a 12-player general slot. In this case, referring to Table 3, in the case of an extended CP following 60 kHz subcarrier spacing, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe may be indicated.

[Table 3]

In addition, as described above, one subframe may correspond to 1 ms on the time axis. In addition, one slot may correspond to 14 symbols on the time axis. In addition, as an example, one slot may correspond to 7 symbols on the time axis. Accordingly, the number of slots and symbols that can be considered may be set differently within 10 ms corresponding to one radio frame. Table 4 may indicate the number of slots and the number of symbols according to each SCS. In this case, as an example, the SCS of 480 KHz in Table 4 below may not be considered, and is not limited to the above-described embodiment.

[Table 4]

Hereinafter, a sounding reference signal (SRS) in NR (New Radio) Rel-15 (Release-15) will be described.

[Table 5]

가 3개의 PRB(Physical Resource Block)에서 사용되는 서브캐리어의 개수(여기서 1개의 PRB에서 사용되는 서브캐리어의 개수는

로 표기함)보다 같거나 클 경우, 베이스 시퀀스(base sequence)는 수학식 3과 같이 Zadoff-chu 시퀀스 기반으로 구성된다. 이 때, 수학식 3에서

는

를 만족하는 수들 중에서 가장 큰 소수(prime number)이다. 예를 들어,

=36(3개의 PRB에서의 서브캐리어 개수와 동일)일 때

=31일 수가 있으며,

= 72(6개의 PRB에서의 서브캐리어 개수와 동일)일 때

=71일 수가 있으며,

=144(12개의 PRB에서의 서브캐리어 개수와 동일)일 때

=139일 수가 있다.As shown in Table 5, the length of the sequence

The number of subcarriers used in three PRBs (Physical Resource Blocks) (where the number of subcarriers used in one PRB is

), the base sequence is configured based on the Zadoff-chu sequence as shown in Equation 3. At this time, in Equation 3

Is

It is the largest prime number among numbers that satisfy. For example,

When =36 (equal to the number of subcarriers in 3 PRBs)

Can be =31,

= 72 (same as the number of subcarriers in 6 PRBs)

Can be =71,

When =144 (equal to the number of subcarriers in 12 PRBs)

=139 could be.

[Equation 3]

와 시퀀스 넘버(sequence number)

를 통해 계산되어지는 루트 인덱스(root index)

값에 따라 서로 다른 시퀀스를 생성하게 된다.In this case, the Zadoff-chu sequence is a sequence group

And sequence number

The root index calculated through

Different sequences are created depending on the value.

[Equation 4]

[Table 6]

로부터 4개의 서브캐리어마다 SRS 시퀀스를 매핑할 경우 comb=4이며,

로부터 2개의 서브캐리어마다 SRS 시퀀스를 매핑할 경우 comb=2이다. 이 때, SRS 시퀀스는 4의 배수에 해당되는 PRB(Physical Resource Block)에 매핑될 수 있으며, 최소 4개의 PRB와 최대 272개의 PRB에 전송될 수 있다. 한편, SRS는 하나의 슬롯 내에서 연속적인 1개, 2개 또는 4개의 심볼에 대해서 전송될 수 있으며, 슬롯 내 시작 심볼 위치

는

로 표현될 수 있다. 이 때,

={0, 1, ..., 5}이다.As shown in Table 6, the SRS sequence is generated by applying a CS (Cyclic Shift) value to the base sequence. The number of antenna ports used for SRS transmission may be 1, 2 or 4, and the CS value is {A+0} when using 1 antenna port, and {A+0} when comb=4 when using 2 antenna ports , A+6} and comb=2 means {A+0, A+4}, and when using 4 antenna ports, comb=4 means {A+0, A+6, A+3, A+9} and comb If =2, it is {A+0, A+4, A+2, A+6}. At this time, CS value A is one of 12 values of {0, 1, ...., 11} when comb=4, and 8 of {0, 1, ...., 7} when comb=2 It is one of the values of eggplant. Also comb is the mapping start subcarrier index of the frequency axis.

When mapping the SRS sequence for every 4 subcarriers from, comb=4,

When the SRS sequence is mapped for every two subcarriers from, comb=2. In this case, the SRS sequence may be mapped to a physical resource block (PRB) corresponding to a multiple of 4, and may be transmitted to a minimum of 4 PRBs and a maximum of 272 PRBs. Meanwhile, the SRS can be transmitted for one, two, or four consecutive symbols in one slot, and the start symbol position in the slot

Is

It can be expressed as At this time,

={0, 1, ..., 5}.

[Table 7]

와 시퀀스 넘버(sequence number)

는 의사 랜덤(pseudo random) 시퀀스 c(n)을 기반으로 그 값이 결정될 수 있다. 이 때, c(n)은 아래 수학식 7에서 보는 것과 같이 매 무선 프레임(radio frame)의 시작에서 그 초기화 값으로 SRS ID를 사용하며, 무선 프레임 내에서 SRS가 전송되는 슬롯/심볼 위치에 따라 최종 값 역시 달라지게 된다. 이 때, SRS ID

는 {0, 1, 2, ...., 1023}의 1024가지의 값 중 하나가 상위단 시그널링(high layer signaling)으로 전송될 수 있다.즉, 아래 수학식 5 및 수학식 6에서 보는 것과 같이 시퀀스 그룹(sequence group)

와 시퀀스 넘버(sequence number)

는 SRS ID와 무선 프레임 내에서 SRS가 전송되는 슬롯/심볼 위치에 따라 서로 다른 값을 가질 수가 있고, 이를 통해 Zadoff-chu 시퀀스 기반의 SRS 를 위한 베이스 시퀀스의 루트 인덱스(rood index) q가 결정되어지므로, 결국 SRS ID 및 무선 프레임 내에서 SRS가 전송되는 슬롯/심볼 위치에 따라 서로 다른 SRS 시퀀스가 생성되게 되는 것이다. As shown in Table 7, sequence group

And sequence number

A value may be determined based on a pseudo random sequence c(n). At this time, c(n) uses the SRS ID as its initialization value at the beginning of each radio frame as shown in Equation 7 below, and according to the slot/symbol position in which the SRS is transmitted within the radio frame. The final value will also be different. At this time, SRS ID

One of 1024 values of {0, 1, 2, ...., 1023} may be transmitted through high layer signaling. That is, as shown in Equations 5 and 6 below, Sequence group together

And sequence number

May have different values according to the SRS ID and the slot/symbol position in which the SRS is transmitted in the radio frame, and through this, the root index q of the base sequence for the Zadoff-chu sequence-based SRS is determined. Therefore, in the end, different SRS sequences are generated according to the SRS ID and the slot/symbol position in which the SRS is transmitted in the radio frame.

[Equation 5]

[Equation 6]

-1) When neither group hopping nor sequence hopping is used

-2) When only group hopping is used and sequence hopping is not used

-3) When only sequence hopping is used and group hopping is not used

[Equation 7]

[Table 8]

와 시퀀스 넘버(sequence number)

에 대해서 상기 수학식 4를 통해

값을 3개 PRB, 6개 PRB, 12개 PRB에 대해서 계산한 결과 값들이다.Table 8 shows each sequence group

And sequence number

For through Equation 4 above

These are the results calculated for 3 PRBs, 6 PRBs, and 12 PRBs.

[Table 9]

As shown in Table 9, the root index values used in the existing SRS sequence are 30 when the length of the SRS sequence is between 36 and 60, and 60 when the length of the SRS sequence is 72 or more.

In the case of NR, a wider bandwidth can be supported for high frequency transmission (for example, a 400Mhz channel bandwidth), and if this is considered, the number of subcarriers used can be significantly increased. Accordingly, since the length of the SRS sequence may be increased, there is a room for additionally selecting a larger number of root indices.

In this situation, NR has twice the physical cell ID (physical cell ID) than LTE, and can have a large number of terminals (User Equipment, UE) access density (for example, 1,000,000 devices/km2) between cells/ When considering inter-terminal interference, a larger number of SRS sequences is required than before.

In particular, 1) transmission of more TX beams from more terminals for a multi-panel terminal and/or acquisition of Channel State Information (CSI) in a single/multi-TRP (Transmission Reception Point) scenario For, 2) In order to support SRS transmission of a higher frequency for a medium/high speed terminal by a reduced channel coherence time, 3) a hot-spot area (for example, 800 The number of SRS base sequences taking into account extremely low intra-cell interference and backward compatibility in order to support SRS transmission from more terminals in an area where more than one terminal is connected) There is a need for an increase.

[Table 10]

That is, as shown in Table 10, the root index values used in the SRS sequence proposed in the present invention are 30 when the SRS sequence length is between 36 and 60, and 60 when the SRS sequence length is between 72 and 120. The number is the same as before, but when the length of the SRS sequence is 144 or more, it can be increased to 120.

Accordingly, in the present invention, a method and apparatus for generating an SRS base sequence capable of maintaining backward compatibility with extremely low intra-cell interference will be described.

3 is a diagram illustrating a method of configuring a root index value for an SRS sequence to which the present disclosure can be applied.

를 유도하기 위한

`값은

를 31등분 한 후에

값을 구하여 계산되어 진다. 여기서

={0, 1, ..., 29}의 30개의 값 중에 하나이며, SRS ID는 {0, 1, ..., 1023}의 1024개의 값 중 하나의 값을 상위단 시그널링을 통해 전송 받게 된다. 이를 통해 총 30개의 서로 다른 루트 인덱스 값의 생성이 가능하다. 여기서 SRS 시퀀스의 길이

에 대하여,

를 만족하는 수들 중에서 가장 큰 소수(prime number)이다. 또한 31등분 하는 것은 3개의 PRB에 해당하는 36개의 서브캐리어에 대응되는

=36를 기준으로 할 경우,

=31이기 때문이다.As shown in the top drawing of Fig. 3, the existing root index value

To induce

`The value is

After dividing into 31 equal parts

It is calculated by finding the value. here

= One of the 30 values of {0, 1, ..., 29}, and the SRS ID receives one of the 1024 values of {0, 1, ..., 1023} through upper level signaling do. Through this, it is possible to create a total of 30 different root index values. Where the length of the SRS sequence

about,

It is the largest prime number among numbers that satisfy. In addition, division into 31 equals 36 subcarriers corresponding to 3 PRBs.

If you base on =36,

Because =31.

As shown in the figure in the middle of FIG. 3, in order to create a total of 30 different root index values, a total of 120 different root index values can be generated. If it is changed to one, backward compatibility is broken when compared with the existing method shown in the top drawing of FIG. 3.

를 유도하기 위한

`값은

를 139등분 한 후에

값을 구하여 계산되어 진다. 여기서

={0, 1, ..., 119}의 120개의 값 중에 하나이며, SRS ID는 {0, 1, ..., 1023}의 1024개의 값 중 하나의 값을 상위단 시그널링을 통해 전송 받게 된다. 이를 통해 총 120개의 서로 다른 루트 인덱스 값의 생성이 가능하다. 여기서 SRS 시퀀스의 길이

에 대하여,

를 만족하는 수들 중에서 가장 큰 소수(prime number)이다. 또한 139등분 하는 것은 12개의 PRB에 해당하는 144개의 서브캐리어에 대응되는

=144를 기준으로 할 경우,

=139이기 때문이다.That is, the root index value

To induce

`The value is

After dividing it into 139 equal parts

It is calculated by finding the value. here

= It is one of 120 values of {0, 1, ..., 119}, and SRS ID receives one of 1024 values of {0, 1, ..., 1023} through upper level signaling do. Through this, it is possible to create a total of 120 different root index values. Where the length of the SRS sequence

about,

It is the largest prime number among numbers that satisfy. In addition, dividing 139 into equal parts corresponds to 144 subcarriers corresponding to 12 PRBs.

If you base on =144,

Because =139.

`값들 사이에서 가운데 지점을

`로 사용하고, 그 이후 추가되는 1024개의 SRS ID에 대해서는 31등분해서 구해진 연속된 2개의

`값들 사이에서 1/4에 해당하는 지점을

`로 사용하고, 그 이후 추가되는 1024개의 SRS ID에 대해서는 31등분해서 구해진 연속된 2개의

`값들 사이에서 3/4 지점을

`로 사용한다.As shown in the bottom drawing of FIG. 3, in order to allow generation of a total of 30 different root index values, a total of 120 different root index values can be generated, the first 1024 SRS IDs have been In the same manner as in 31 divisions, and for 1024 SRS IDs added thereafter, two consecutive two obtained by dividing into 31 divisions.

`Move the middle point between values

Used as `, and for 1024 SRS IDs added thereafter, two consecutive

`Put a quarter of the point between the values.

Used as `, and for 1024 SRS IDs added thereafter, two consecutive

`Take 3/4 points between values

Used as `.

` 가지므로 역-호환성(backward compatibility)이 유지될 수 있으며, 추가되는

` 값으로 정확히 기존 값들의 사이에서 1/2, 1/4, 3/4 지점으로 최적화된 값을 사용하기에 극히 낮은 셀 내(intra-cell) 간섭(interference)을 기대할 수 있는 장점이 있다. In this case, for the first 1024 SRS IDs,

`As it has, backward compatibility can be maintained, and

`As a value, since the optimized value is used at 1/2, 1/4, 3/4 point between the existing values, there is an advantage that extremely low intra-cell interference can be expected.

In addition, the base station can control whether the SRS ID has the same values as before or has more values by higher-level signaling, and the SRS base sequence added accordingly can be adjusted. There is an advantage that the terminal can easily recognize.

That is, summarized as follows.

When this is expressed as Equation 4, Equation 4 may be changed as shown in Equation 8 below.

[Equation 8]

In addition, Equations 5 and 7 may be changed to Equations 9 and 10, respectively, when considering backward compatibility.

[Equation 9]

[Equation 10]

[Table 11]

와 시퀀스 넘버(sequence number)

에 대해서 상기 수학식 8를 통해

값을 6개 PRB, 12개 PRB에 대해서 계산한 결과 값들이다.Table 11 shows each sequence group

And sequence number

For through Equation 8 above

These are the result values calculated for 6 PRBs and 12 PRBs.

값을 0, 1, -1, 2의 총 4개를 사용하여 총 120개의 서로 다른 루트 인덱스 값의 생성이 가능하도록 하여 SRS 베이스 시퀀스의 개수를 늘릴 수도 있다.As another embodiment of the present invention, a sequence number

A total of 120 different root index values can be generated by using a total of 4 values of 0, 1, -1, and 2, thereby increasing the number of SRS base sequences.

값을 0 또는 1이며, SRS ID가 {1024, 1025, ..., 2047}의 추가되는 1024개의 값 중 하나 일 경우 시퀀스 넘버(sequence number)

값을 -1 또는 2이다. 본 실시예 또한 상위단 시그널링의 의해 SRS ID가 기존과 동일하게 {0, 1, ..., 1023}이 값들을 가지는지 아니면 그 이상의 값들을 가지는 지 기지국은 조절할 수 있고, 이에 따라 추가되는 SRS 베이스 시퀀스를 단말이 쉽게 인식할 수 있다.At this time, if the SRS ID is one of 1024 values of {0, 1, ..., 1023}, the sequence number is the same as before.

If the value is 0 or 1, and the SRS ID is one of the additional 1024 values of {1024, 1025, ..., 2047}, the sequence number

The value is -1 or 2. In this embodiment, the base station can control whether the SRS ID has the same values as the previous ones or more values of {0, 1, ..., 1023} by higher-end signaling, and the SRS added accordingly The base sequence can be easily recognized by the terminal.

That is, summarized as follows.

When this is expressed by Equation 6, a part of Equation 6 may be changed as shown in Equation 11 below.

[Equation 11]

In addition, Equations 5 and 7 may be changed to Equations 9 and 10, respectively, when considering backward compatibility.

[Table 12]

와 시퀀스 넘버(sequence number)

에 대해서, 상기 수학식 4에 상기 수학식 11을 통해 변경된

에 대한 계산식을 적용하여

값을 12개 PRB에 대해서 계산한 결과 값들이다.Table 12 shows each sequence group

And sequence number

For, the changed through Equation 11 in Equation 4

By applying the formula for

These are the results of calculating the values for 12 PRBs.

4 is a diagram illustrating an operation of a base station and a terminal to which the present disclosure can be applied.

Referring to FIG. 4, a base station 410 may provide SRS sequence related information including an SRS ID value to UEs through higher layer signaling (411). As an example, based on the above, the SRS ID may be one of 1024 values of {0, 1, ..., 1023} as before, and 1024 to increase the number of SRS sequences by generating an additional root index value. It may be more than one value.

The terminal 420 may calculate the root index q value in consideration of the transmitted SRS ID value (421). For example, based on the above, if the SRS ID is the same as before, when the value is 1024 values of {0, 1, ..., 1023}, the root index q value of the same value is calculated, but the SRS ID is 1024 or more. In this case, as described in Equations 8 to 11, an additional root index q value may be calculated.

The terminal 420 may generate a base sequence from the root index q and apply a cyclic shift (CS) value to generate an SRS sequence (422).

The terminal 420 may transmit the SRS to the base station by mapping the generated SRS sequence to a specific time-frequency resource in the slot (423).

The base station 410 may receive the SRS transmitted from the terminal (412).

The base station 410 extracts the SRS sequence from the SRS received from the terminal, and compares the SRS sequence generated by itself through the SRS sequence-related information transmitted to the terminal in the presence of the base station with the extracted SRS sequence to measure the uplink channel. There is (413).

5 is a diagram illustrating a configuration of a base station apparatus and a terminal apparatus to which the present disclosure can be applied.

The base station apparatus 500 may include a processor 520, an antenna unit 512, a transceiver 514, and a memory 517.

The processor 520 performs baseband-related signal processing and may include an upper layer processing unit 530 and a physical layer processing unit 540. The upper layer processor 530 may process an operation of a medium access control (MAC) layer, a radio resource control (RRC) layer, or an upper layer higher than the medium access control (MAC) layer. The physical layer processing unit 540 may process an operation of a physical (PHY) layer (eg, uplink reception signal processing, downlink transmission signal processing, sidelink transmission signal processing, sidelink reception signal processing). . In addition to performing baseband-related signal processing, the processor 520 may control the overall operation of the base station apparatus 500.

The antenna unit 512 may include one or more physical antennas, and may support multiple input multiple output (MIMO) transmission and reception when a plurality of antennas are included. The transceiver 514 may include a radio frequency (RF) transmitter and an RF receiver. The memory 517 may store information processed by the processor 520, software related to the operation of the base station apparatus 500, an operating system, an application, and the like, and may include components such as a buffer.

The processor 520 of the base station 500 may be configured to implement the operation of the base station in the embodiments described in the present invention.

The terminal device 550 may include a processor 570, an antenna unit 562, a transceiver 564, and a memory 566.

The processor 570 performs baseband-related signal processing and may include an upper layer processing unit 580 and a physical layer processing unit 590. The upper layer processing unit 580 may process the operation of the MAC layer, the RRC layer, or higher layers. The physical layer processing unit 590 may process operations of the PHY layer (eg, downlink reception signal processing, uplink transmission signal processing, sidelink transmission signal processing, sidelink reception signal processing). In addition to performing baseband-related signal processing, the processor 570 may also control the overall operation of the terminal device 550.

The antenna unit 562 may include one or more physical antennas, and may support MIMO transmission/reception when including a plurality of antennas. The transceiver 564 may include an RF transmitter and an RF receiver. The memory 566 may store information processed by the processor 570, software related to the operation of the terminal device 550, an operating system, an application, and the like, and may include components such as a buffer.

The processor 570 of the terminal device 550 may be set to implement the operation of the terminal in the embodiments described in the present invention.

In this case, as an example, the processor 520 of the base station device 500 may transmit SRS sequence related information including the SRS ID value to the terminal device 1750 through higher layer signaling, as described above.

In addition, as an example, the processor 520 of the base station apparatus 500 extracts the SRS sequence from the SRS received from the terminal, and extracts the SRS sequence generated by the base station through the SRS sequence related information previously transmitted to the terminal. The uplink channel can be measured by comparing it with the sequence.

In addition, as an example, the processor 570 of the terminal device 550 may calculate the root index q value in consideration of the SRS ID value transmitted from the base station device 500 as described above. That is, based on the above, when the SRS ID is the same as before, when 1024 values of {0, 1, ..., 1023} are calculated, the root index q value of the same value is calculated, but when the SRS ID is 1024 or more. As described in Equations 8 to 11, an additional root index q value may be calculated.

In addition, as an example, the processor 570 of the terminal device 550 may generate a base sequence from the root index q as described above and apply a cyclic shift (CS) value to generate an SRS sequence.

In the operation of the base station apparatus 1700 and the terminal apparatus 1750, the items described in the examples of the present invention may be equally applied, and redundant descriptions will be omitted.

Although the exemplary methods of the present disclosure are expressed as a series of operations for clarity of description, this is not intended to limit the order in which steps are performed, and each step may be performed simultaneously or in a different order if necessary. In order to implement the method according to the present disclosure, the exemplary steps may include additional steps, other steps may be included excluding some steps, or may include additional other steps excluding some steps.

Various embodiments of the present disclosure are not intended to list all possible combinations, but to describe representative aspects of the present disclosure, and matters described in the various embodiments may be applied independently or may be applied in combination of two or more.

In addition, various embodiments of the present disclosure may be implemented by hardware, firmware, software, or a combination thereof. For implementation by hardware, one or more ASICs (Application Specific Integrated Circuits), DSPs (Digital Signal Processors), DSPDs (Digital Signal Processing Devices), PLDs (Programmable Logic Devices), FPGAs (Field Programmable Gate Arrays), general purpose It may be implemented by a processor (general processor), a controller, a microcontroller, a microprocessor, or the like.

The scope of the present disclosure is software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that cause an operation according to the method of various embodiments to be executed on a device or computer, and such software or It includes a non-transitory computer-readable medium (non-transitory computer-readable medium) which stores instructions and the like and is executable on a device or a computer.

Base Station: 500 Processor: 520
Upper layer processing unit: 530 Physical layer processing unit: 540
Antenna part: 512 Transceiver: 514
Memory: 516 Terminal: 550
Processor: 570 Upper layer processing unit: 580
Physical layer processing unit: 590 Antenna unit: 562
Transceiver: 564 Memory: 566

Claims (1)

In a method for a terminal to transmit a sounding reference signal (SRS),
Receiving, by the terminal, SRS sequence related information including an SRS ID value from a base station,
Calculating, by the terminal, a root index q value based on information received from the base station,
Generating, by the terminal, a base sequence from the root index q and applying a cyclic shift (CS) value thereto to generate an SRS sequence; and
A communication method comprising the step of the UE mapping the generated SRS sequence to a time-frequency resource and transmitting the SRS to the base station,
A communication method in which a root index q is calculated differently by distinguishing between the case where the SRS ID value is less than 1024 and the case where the SRS ID value is 1024 or more.

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