CN110971383B

CN110971383B - Method and device for sending and receiving reference signal

Info

Publication number: CN110971383B
Application number: CN201910020561.0A
Authority: CN
Inventors: 费永强; 郭志恒; 谢信乾
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2018-09-28
Filing date: 2019-01-09
Publication date: 2021-07-16
Anticipated expiration: 2039-01-09
Also published as: CN110971383A

Abstract

The application provides a method and a device for sending and receiving reference signals, which are used for providing a method for measuring among base stations. The method comprises the following steps: the base station 1 transmits a reference signal on the second resource to the base station 2. The second resource comprises M continuous downlink OFDM symbols, and in the M continuous downlink OFDM symbols, reference signals borne between any two adjacent OFDM symbols meet the cyclic characteristic in a time domain, or phase difference values between the reference signals borne on subcarriers of any two OFDM symbols and subcarrier indexes are in a linear relation; the base station 2 determines a first resource for receiving the reference signal, where the first resource includes an uplink OFDM symbol and/or a guard interval, and the base station 2 receives the reference signal on the first resource.

Description

Method and device for sending and receiving reference signal

The present application claims priority of chinese patent application entitled "a method and apparatus for transmitting and receiving reference signal" filed by chinese patent office on 28/9/2018 with application number 201811143498.1, the entire contents of which are incorporated herein by reference.

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for transmitting and receiving a reference signal.

Background

In a wireless communication system, such as a New Radio (NR), a Long Term Evolution (LTE), an evolved LTE-advanced (LTE-a) and other communication systems, if the system uses a Time Division Duplex (TDD) duplex mode, a cross-link interference (CLI) may be generated between a Base Station (BS) and a base station. The term "alien interference between base stations" mainly refers to that a Downlink (DL) signal transmitted by one base station interferes with an Uplink (UL) signal of another base station, and the uplink signal may be a signal transmitted by a User Equipment (UE) to the base station, for example. For example, when a first base station transmits a downlink signal, a second base station is receiving the uplink signal, and the downlink signal transmitted by the first base station is generally high in power and may be received by the second base station, which may interfere with the second base station receiving the uplink signal.

CLI between base stations typically occurs in situations where the transmission directions of two TDD cells operating at the same frequency are different. Therefore, if the TDD cell has the same transmission direction, CLI is not usually generated. There are exceptions, however: two base stations located at far apart geographical locations, even though their transmission directions are the same (i.e. receiving uplink/simultaneously transmitting downlink signals), because the distance between them is long, the downlink signal transmitted by one base station has already passed a significant time delay when reaching another base station, and at this time, the other base station has already switched from the downlink transmission direction to the uplink reception direction, so the downlink signal of the far-end base station interferes with the reception of the uplink signal of the local base station, i.e. CLI is generated.

The ultra-far interference between base stations is usually due to tropospheric curvature phenomena; whether inter-base station interference, interference distance and time delay are caused is affected by geographical location and weather, and thus has a great uncertainty. In order to combat the ultra-long-distance interference, methods such as reducing the transmission power by the interfering station, reducing the number of downlink transmission symbols by the interfering station, etc. may be used, but before implementing the interference reduction scheme, measurement between base stations is first required to identify the existence of the ultra-long-distance interference or identify the interfering base station.

In NR, there is currently no standardization of reference signals for measurements between NR base stations (gdnodeb, gNB), i.e., between gNB and gNB, nor standardization of associated measurement procedures.

Disclosure of Invention

The application provides a method and a device for sending and receiving reference signals, which are used for providing a reference signal for measurement between NR base stations.

In a first aspect, an embodiment of the present application provides a method for sending a reference signal, where the method may be executed by a network device, and includes:

transmitting reference signals carried on M consecutive OFDM symbols;

in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is determined by an index of the first subcarrier, where the first OFDM symbol and the second OFDM symbol are any two OFDM symbols of the M consecutive OFDM symbols, and M is an integer greater than or equal to 2.

The scheme provides a method for measuring among base stations, and reference signals carried by different OFDM symbols meet the cyclic characteristic, so that a receiver can obtain a complete reference signal in a detection window when detecting the reference signals.

In one possible design, further comprising: in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is w1, a phase difference between a phase of a reference signal carried on a second subcarrier of the first OFDM symbol and a phase of a reference signal carried on a second subcarrier of the second OFDM symbol is w2, a phase difference between a phase of a reference signal carried on a third subcarrier of the first OFDM symbol and a phase of a reference signal carried on a third subcarrier of the second OFDM symbol is w3, and a phase difference between a phase of a reference signal carried on a fourth subcarrier of the first OFDM symbol and a phase of a reference signal carried on a fourth subcarrier of the second OFDM symbol is w 4; if the difference between the index of the second subcarrier and the index of the first subcarrier is equal to the difference between the index of the fourth subcarrier and the index of the third subcarrier, the value of (w2-w1) modulo 2 pi is equal to the value of (w4-w3) modulo 2 pi.

Through the design, the phase difference and the subcarrier index are in a linear relation between different OFDM symbols, so that the reference signals carried by different OFDM symbols meet the cyclic characteristic, and a receiving party can obtain a complete reference signal in a detection window.

In one possible design, the phase difference between the phase of the reference signal carried on the first subcarrier of the first OFDM symbol and the phase of the reference signal carried on the first subcarrier of the second OFDM symbol is further determined by the symbol length of the OFDM symbol and/or the cyclic prefix CP length of the OFDM symbol.

Through the design, the phase difference is determined based on the subcarrier index, the symbol length of the OFDM symbol and/or the cyclic prefix CP length of the OFDM symbol, so that reference signals carried by different OFDM symbols meet the cyclic characteristic, and a receiving party can obtain a complete reference signal in a detection window.

In one possible design, the first OFDM symbol is separated from the second OFDM symbol by X OFDM symbols, the first OFDM symbol is earlier in the time domain than the second OFDM symbol, and X is an integer greater than or equal to 0; the CP length of the OFDM symbol is determined by the CP lengths of the X OFDM symbols and the CP length of a second OFDM symbol.

The above design provides a relation between reference signals carried by different OFDM symbols in case of satisfying cyclic characteristics.

In one possible design, in any two adjacent OFDM symbols of the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a next OFDM symbol and a phase of a reference signal carried on a first subcarrier of a previous OFDM symbol is 2 pi Lk/N, where N is a symbol length of the OFDM symbol, L is a CP length of the OFDM symbol, and k is an index of the first subcarrier.

Through the determination mode of the phase difference between the reference signals carried by the adjacent OFDM symbols provided by the design, the reference signals carried by different OFDM symbols meet the cyclic characteristic, so that a receiving party can obtain a complete reference signal in a detection window.

In aIn a possible design, in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th OFDM symbol and a phase of a reference signal carried on a first subcarrier of a v-th OFDM symbol is

Wherein N is a symbol length of the OFDM symbol, Ln is a CP length of the nth OFDM symbol, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

Through the determination mode of the phase difference between the reference signals carried by different OFDM symbols provided by the design, the reference signals carried by different OFDM symbols meet the cyclic characteristic, so that a receiver can obtain a complete reference signal in a detection window.

In one possible design, the M consecutive OFDM symbols are the last M OFDM symbols of a downlink transmission portion of an uplink and downlink switching period.

In the above design, on one hand, the maximum range of interference can be determined, because the RS is the last N symbols of downlink transmission, after the receiver detects the RS, it can be determined that the range after the time domain position where the RS is located is not interfered by the transmitter in the different direction, so that interference cancellation means can be further applied, for example, lower-order modulation, lower code rate, and the like are applied to the region interfered by CLI; on the other hand, the success rate of detection can be guaranteed to the greatest extent.

In one possible design, the reference signal is carried on K subcarriers, K is less than or equal to Kmax, and Kmax is the maximum number of subcarriers in the system; through the design, the same OFDM symbol can not only carry reference signals, but also carry other signals, such as data signals, so that the base stations can carry out channel measurement between the base stations in the same time, and can also carry out data transmission between the base stations and user equipment.

In a second aspect, an embodiment of the present application provides a method for receiving a reference signal, where the method may be executed by a network device, and includes: determining a first resource for receiving a reference signal, wherein the first resource comprises an uplink OFDM symbol and/or a guard interval; receiving a reference signal on the first resource; the reference signal is sent through a second resource, where the second resource includes M consecutive downlink OFDM symbols; in the M consecutive downlink OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is determined by an index of the first subcarrier, where the first OFDM symbol and the second OFDM symbol are OFDM symbols of any two of the M consecutive downlink OFDM symbols, and M is an integer greater than or equal to 2.

In one possible design, further comprising:

in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is w1, a phase difference between a phase of a reference signal carried on a second subcarrier of the first OFDM symbol and a phase of a reference signal carried on a second subcarrier of the second OFDM symbol is w2, a phase difference between a phase of a reference signal carried on a third subcarrier of the first OFDM symbol and a phase of a reference signal carried on a third subcarrier of the second OFDM symbol is w3, and a phase difference between a phase of a reference signal carried on a fourth subcarrier of the first OFDM symbol and a phase of a reference signal carried on a fourth subcarrier of the second OFDM symbol is w 4;

if the difference between the index of the second subcarrier and the index of the first subcarrier is equal to the difference between the index of the fourth subcarrier and the index of the third subcarrier, the value of (w2-w1) modulo 2 pi is equal to the value of (w4-w3) modulo 2 pi.

In one possible design, in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th OFDM symbol and a phase of a reference signal carried on a first subcarrier of a v-th OFDM symbol is

In a third aspect, an embodiment of the present application provides a method for sending a reference signal, where the method may be executed by a network device, and includes: transmitting reference signals carried on M consecutive OFDM symbols; in the M consecutive OFDM symbols, any two adjacent OFDM symbols are, in the time domain, the same signal obtained by performing cyclic shift on the reference signal carried by the portion of the latter OFDM symbol excluding the CP as the reference signal carried by the portion of the former OFDM symbol excluding the CP, and the length of the cyclic shift is determined by the length of the cyclic prefix CP of the OFDM symbol.

According to the scheme, a method for measuring between base stations is provided, and two adjacent OFDM symbols meet the cyclic shift characteristic, so that reference signals carried by different OFDM symbols meet the cyclic characteristic, and a receiving party can obtain a complete reference signal in a detection window when detecting the reference signals.

In one possible design, the CP length of the OFDM symbol is a CP length of a subsequent OFDM symbol of the two adjacent OFDM symbols.

In one possible design, in M consecutive OFDM symbols, a cyclic shift (u-v) · L long is performed on the reference signal carried by the u-th OFDM symbol excluding the CP portion and the reference signal carried by the v-th OFDM symbol excluding the CP portion to obtain the same signal, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and L is the CP length of the OFDM symbol.

According to the design, the cyclic shift characteristic is satisfied between any two OFDM symbols, so that the cyclic characteristic is satisfied between reference signals carried by different OFDM symbols, and a receiver can obtain a complete reference signal in a detection window.

In one possible design, in the M consecutive OFDM symbols, the reference signal carried by the part of the u-th OFDM symbol excluding the CP is performed with the reference signal carried by the part of the v-th OFDM symbol excluding the CP

The signals obtained by long cyclic shift are the same, Ln is the CP length of the nth OFDM symbol, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than uAnd (4) counting.

In a fourth aspect, an embodiment of the present application provides a method for receiving a reference signal, where the method may be executed by a network device, and includes: determining a first resource for receiving a reference signal, wherein the first resource comprises an uplink OFDM symbol and/or a guard interval; receiving a reference signal on the first resource; the reference signal is sent through a second resource, where the second resource includes M consecutive downlink OFDM symbols; in the M consecutive OFDM symbols, in the time domain, any two adjacent OFDM symbols are the same as a signal obtained by performing cyclic shift on the reference signal carried by the part of the next OFDM symbol excluding the CP and the reference signal carried by the part of the previous OFDM symbol excluding the CP, and the length of the cyclic shift is determined by the length of the cyclic prefix CP of the OFDM symbol.

Signals obtained by long cyclic shift are the same, Ln is the CP length of the nth OFDM symbol, u is an integer which is greater than 1 and less than or equal to M, and v is an integer which is greater than or equal to 1 and less than u.

In a fifth aspect, an embodiment of the present application provides a method for receiving a reference signal, where the method may be executed by a network device, and includes:

determining a first resource for receiving a reference signal according to the obtained first information; wherein, the first information comprises time domain resource and/or frequency domain resource position information used for bearing reference signals; receiving a reference signal on the first resource.

According to the scheme, for the base stations with short distance, because the signal transmission time delay can be ignored, the sending time of the sending end can be regarded as the receiving time of the receiving end, and therefore the receiving end can know the resource position bearing the reference signal (namely the resource position of the reference signal sent by the sending end) in advance, and therefore the reference signal is received at the determined resource position. And then, channel measurement is carried out according to the reference signal, or an interference base station is determined.

In one possible design, further comprising: obtaining second information, wherein the second information comprises the reference signal or parameter information required for generating the reference signal; determining that the reference signal is received on the first resource according to the second information, or performing channel estimation according to the second information and the received reference signal.

In one possible design, the first resource may include a guard time interval, or the first resource may include M downlink OFDM symbols.

In a sixth aspect, an embodiment of the present application provides a method for sending a reference signal, including:

transmitting reference signals carried on Z consecutive basic resources; the basic resource comprises Y continuous third Orthogonal Frequency Division Multiplexing (OFDM) symbols, and a Cyclic Prefix (CP) and/or a Cyclic Suffix (CS); reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP;

in the Z consecutive basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is determined by an index of the first subcarrier, where the first basic resource and the second basic resource are any two basic resources of the Z consecutive basic resources, and Z and Y are integers greater than or equal to 2.

Illustratively, the length of the basic resource is equal to the sum of the lengths of Y fourth OFDM symbols, which include the CP.

Illustratively, the third OFDM symbol and the fourth OFDM symbol have the same symbol length, that is, the third OFDM symbol and the fourth OFDM symbol excluding the CP and/or CS are equal.

In one possible design, further comprising:

in the Z consecutive basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is w1, a phase difference between a phase of a reference signal carried on a second subcarrier of the first basic resource and a phase of a reference signal carried on a second subcarrier of the second basic resource is w2, a phase difference between a phase of a reference signal carried on a third subcarrier of the first basic resource and a phase of a reference signal carried on a third subcarrier of the second basic resource is w3, a phase difference between a phase of the reference signal carried on the fourth subcarrier of the first basic resource and a phase of the reference signal carried on the fourth subcarrier of the second basic resource is w 4;

In one possible design, when the basic resource includes only Y consecutive third OFDM symbols and one CP, a phase difference between a phase of a reference signal carried on the first subcarrier of the first basic resource and a phase of a reference signal carried on the first subcarrier of the second basic resource is further determined by a symbol length of the third OFDM symbol and/or a CP length of the basic resource.

In one possible design, the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CP length of the basic resource is determined by the CP lengths of the X basic resources and the CP length of the second basic resource.

In a possible design, when the basic resources only include Y consecutive third OFDM symbols and a cyclic prefix CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource of any two adjacent basic resources in the Z consecutive basic resources is 2 pi Lk/N, where N is a symbol length of the third OFDM symbol, L is a CP length of the basic resource, and k is an index of the first subcarrier.

In one possible design, when the basic resource includes only Y consecutive third OFDM symbols and one cyclic prefix CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th basic resource and a phase of a reference signal carried on a first subcarrier of a v-th basic resource in the Z consecutive basic resources is

Wherein N is a symbol length of the third OFDM symbol, Ln is a CP length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

In one possible design, when the basic resource includes only Y consecutive third OFDM symbols and one CS, a phase difference between a phase of a reference signal carried on the first subcarrier of the first basic resource and a phase of a reference signal carried on the first subcarrier of the second basic resource is further determined by a symbol length of the third OFDM symbol and/or a CS length of the basic resource.

In one possible design, the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CS length of the basic resource is determined by the CS lengths of the X basic resources and the CS length of the first basic resource.

In one possible design, when the basic resources include only Y consecutive third OFDM symbols and one CS, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource of any two adjacent basic resources in the Z consecutive basic resources is 2 pi Jk/N, where N is a symbol length of the third OFDM symbol, J is a CS length of the basic resource, and k is an index of the first subcarrier.

In one possible design, when the basic resources include only Y consecutive third OFDM symbols and one CS, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th basic resource and a phase of a reference signal carried on a first subcarrier of a v-th basic resource in the Z consecutive basic resources is

Wherein N is a symbol length of the third OFDM symbol, Jn is a CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

In one possible design, when the basic resources include Y consecutive third OFDM symbols, one CS, and one CP, a phase difference between a phase of a reference signal carried on the first subcarrier of the first basic resource and a phase of a reference signal carried on the first subcarrier of the second basic resource is further determined by a symbol length of the third OFDM symbol, a CS length of the basic resource, and a CP length of the basic resource.

In one possible design, the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CS length of the basic resource is determined by the CS lengths of the X basic resources and the CS length of the first basic resource, and the CP length of the basic resource is determined by the CP lengths of the X basic resources and the CP length of the second basic resource.

In one possible design, when the basic resources include Y consecutive third OFDM symbols, one CS, and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource of any two adjacent basic resources in the Z consecutive basic resources is 2 pi (L + J) k/N, where N is a symbol length of the third OFDM symbol, L is a CP length of the basic resource, J is a CS length of the basic resource, and k is an index of the first subcarrier.

In a possible design, when the basic resources include Y consecutive third OFDM symbols, one CS, and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th basic resource and a phase of a reference signal carried on a first subcarrier of a v-th basic resource in the Z consecutive basic resources is

Wherein N is a symbol length of the third OFDM symbol, Ln is a CP length of the nth basic resource, Jn is a CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

In one possible design, the Z consecutive basic resources are the last Z basic resources of the downlink transmission part of the uplink and downlink switching period.

In a seventh aspect, an embodiment of the present application provides a method for sending a reference signal, including:

transmitting reference signals carried on Z consecutive basic resources;

wherein the basic resource comprises Y continuous third Orthogonal Frequency Division Multiplexing (OFDM) symbols and a Cyclic Prefix (CP); reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP;

in the Z consecutive basic resources, in the time domain, any two adjacent basic resources are the same as a signal obtained by performing cyclic shift on a reference signal carried on a third OFDM symbol included in a subsequent basic resource and a reference signal carried on a third OFDM symbol included in a previous basic resource, and a length of the cyclic shift is determined by a CP length of the basic resource.

In one possible design, the CP length of the basic resource is the CP length of the latter basic resource of the two adjacent basic resources.

In one possible design, in Z consecutive basic resources, a reference signal carried on a third OFDM symbol included in a u-th basic resource is the same as a signal obtained by performing (u-v) · L-long cyclic shift on a reference signal carried on a third OFDM symbol included in a v-th basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and L is a CP length of the basic resource.

In one possible design, in the Z consecutive basic resources, a reference signal carried on a third OFDM symbol included in a u-th basic resource is performed with a reference signal carried on a third OFDM symbol included in a v-th basic resource

The signals obtained by the long cyclic shift are the same, Ln is the CP length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, and v is an integer greater than or equal to 1 and less than u.

In an eighth aspect, an embodiment of the present application provides a method for sending a reference signal, including:

transmitting reference signals carried on Z consecutive basic resources;

wherein the basic resource comprises Y continuous third Orthogonal Frequency Division Multiplexing (OFDM) symbols and a cyclic postfix (CS); reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP;

in the Z consecutive basic resources, in the time domain, a cyclic shift performed on a reference signal carried on a third OFDM symbol included in a subsequent basic resource is the same as a signal obtained by a cyclic shift performed on a reference signal carried on a third OFDM symbol included in a previous basic resource, and a length of the cyclic shift is determined by a CS length of the basic resource.

In one possible design, the CS length of the basic resource is the CS length of the previous basic resource in the two adjacent basic resources.

In one possible design, in Z consecutive basic resources, a reference signal carried on a third OFDM symbol included in a u-th basic resource is the same as a signal obtained by performing (u-v) · J-length cyclic shift on a reference signal carried on a third OFDM symbol included in a v-th basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and J is a CS length of the basic resource.

The signals obtained by the long cyclic shift are the same, Jn is the CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, and v is an integer greater than or equal to 1 and less than u.

In a ninth aspect, an embodiment of the present application provides a method for sending a reference signal, including:

transmitting reference signals carried on Z consecutive basic resources;

wherein the basic resource comprises Y consecutive third orthogonal frequency division multiplexing, OFDM, symbols, and a cyclic prefix, CP, and a cyclic suffix, CS; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP;

in the Z consecutive basic resources, in the time domain, a reference signal carried on a third OFDM symbol included in a subsequent basic resource is the same as a signal obtained by cyclically shifting a reference signal carried on a third OFDM symbol included in a previous basic resource, and a length of the cyclic shift is determined by a CP of the basic resource and a CS length of the basic resource.

In a possible design, the CS length of the basic resource is a CS length of a previous basic resource in the two adjacent basic resources, and the CP length of the basic resource is a CP length of a subsequent basic resource in the two adjacent basic resources.

In one possible design, in Z consecutive basic resources, a reference signal carried on a third OFDM symbol included in a u-th basic resource is the same as a signal obtained by performing (u-v) · (L + J) long cyclic shift on a reference signal carried on a third OFDM symbol included in a v-th basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, L is a CP length of the basic resource, and J is a CS length of the basic resource.

The signals obtained by the long cyclic shift are the same, Ln is the CP length of the nth basic resource, Jn is the CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, and v is an integer greater than or equal to 1 and less than u.

In a tenth aspect, an embodiment of the present application provides a method for receiving a reference signal, including:

determining a first resource for receiving a reference signal, wherein the first resource comprises an uplink OFDM symbol and/or a guard interval;

receiving a reference signal on the first resource; the reference signal is transmitted through a second resource, which includes Z consecutive basic resources; the basic resource comprises Y continuous third orthogonal frequency division multiplexing OFDM symbols, and a cyclic prefix CP and/or a cyclic suffix CS; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP; the second resource is a downlink transmission resource (for example, the second resource includes a downlink OFDM symbol which is a third OFDM symbol);

In one possible design, further comprising:

In one possible design, when the basic resources only include Y consecutive third OFDM symbols and one cyclic prefix CP, the Z consecutive basic resources are carried by the u-th basic resourceThe phase difference between the phase of the reference signal on the first subcarrier of the source and the phase of the reference signal carried on the first subcarrier of the v-th fundamental resource is

In one possible design, when the basic resources include only Y consecutive third OFDM symbols and one CS, of the Z consecutive basic resources, the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the v-th basic resource are the sameThe phase difference between the phases of the reference signals on the first subcarrier of the resource is

In one possible design, when the basic resource includes Y consecutive third OFDM symbols, one CS, and one CP, the Z consecutive basesIn the resource, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the first subcarrier of the v-th basic resource is

In an eleventh aspect, an embodiment of the present application provides a method for receiving a reference signal, including:

receiving a reference signal on the first resource; the reference signal is transmitted through a second resource, which includes Z consecutive basic resources; the basic resource comprises Y continuous third orthogonal frequency division multiplexing OFDM symbols and a cyclic prefix CP; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP; the second resource is a downlink transmission resource (for example, the second resource includes a downlink OFDM symbol which is a third OFDM symbol);

In a twelfth aspect, an embodiment of the present application provides a method for receiving a reference signal, including:

receiving a reference signal on the first resource; the reference signal is transmitted through a second resource, which includes Z consecutive basic resources; the basic resource comprises Y continuous third Orthogonal Frequency Division Multiplexing (OFDM) symbols and a cyclic suffix CS; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP; the second resource is a downlink transmission resource (for example, the second resource includes a downlink OFDM symbol which is a third OFDM symbol);

In a thirteenth aspect, an embodiment of the present application provides a method for receiving a reference signal, including:

receiving a reference signal on the first resource; the reference signal is transmitted through a second resource, which includes Z consecutive basic resources; the basic resource comprises Y continuous third orthogonal frequency division multiplexing OFDM symbols, a cyclic prefix CP and a cyclic suffix CS; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP; the second resource is a downlink transmission resource (for example, the second resource includes a downlink OFDM symbol which is a third OFDM symbol);

In a possible arrangementIn the Z consecutive basic resources, a reference signal carried on a third OFDM symbol included in a u-th basic resource is performed with a reference signal carried on a third OFDM symbol included in a v-th basic resource

In a fourteenth aspect, an apparatus is provided. The apparatus provided by the present application has the functionality to implement the network device behavior in the above-described method aspect, comprising means (means) for performing the steps or functionalities described in the above-described method aspect. The steps or functions may be implemented by software, or hardware (e.g., a circuit), or by a combination of hardware and software.

In one possible design, the apparatus includes one or more processors and a communication unit. The one or more processors are configured to support the apparatus to perform the corresponding functions of the network device in the above method. For example, a reference signal is carried on an OFDM symbol and transmitted. The communication unit is used for supporting the device to communicate with other equipment and realizing receiving and/or sending functions. For example, a reference signal is transmitted.

Optionally, the apparatus may also include one or more memories for coupling with the processor that hold the necessary program instructions and/or data for the apparatus. The one or more memories may be integral with the processor or separate from the processor. The present application is not limited.

The communication unit may be a transceiver, or a transceiving circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The apparatus may be a base station, a gNB, a TRP, or the like, and the communication unit may be a transceiver, or a transceiver circuit. Optionally, the transceiver may also be an input/output circuit or interface.

The device may also be a communication chip. The communication unit may be an input/output circuit or an interface of the communication chip.

In another possible design, the apparatus includes a transceiver, a processor, and a memory. The processor is configured to control the transceiver or the input/output circuit to transceive signals, the memory is configured to store a computer program, the processor is configured to execute the computer program in the memory, to cause the apparatus to perform the method performed by the network device in any one of the possible implementations of the first aspect or the first aspect, or to perform the method performed by the network device in any one of the possible implementations of the second aspect or the second aspect, or to perform the method performed by the network device in any one of the possible implementations of the third aspect or the third aspect, or to perform the method performed by the network device in any one of the possible implementations of the fourth aspect or the fourth aspect, or to perform the method performed by the network device in any one of the possible implementations of the fifth aspect or the fifth aspect, or to perform the method performed by the network device in any one of the possible implementations of the sixth aspect or the sixth aspect, or perform a method performed by a network device in any one of the seventh aspect or any one of the eighth aspect or the ninth aspect or any one of the tenth aspect or any one of the eleventh aspect or any one of the twelfth aspect or any one of the thirteenth aspect or any one of the possible implementations.

In a fifteenth aspect, a system is provided, which comprises at least two network devices as described above.

A sixteenth aspect provides a computer-readable storage medium for storing a computer program comprising instructions for carrying out the method of the first aspect or any one of the possible implementations of the first aspect, or comprising instructions for carrying out the method of the second aspect or any one of the possible implementations of the second aspect, or comprising instructions for carrying out the method of the third aspect or any one of the possible implementations of the third aspect, or comprising instructions for carrying out the method of the fourth aspect or any one of the possible implementations of the fourth aspect, or comprising instructions for carrying out the method of the fifth aspect or any one of the possible implementations of the fifth aspect, or comprising instructions for carrying out the method of the sixth aspect or any one of the possible implementations of the sixth aspect, or comprising instructions for carrying out the method of any one of the possible implementations of the seventh aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the eighth aspect or the eighth aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the ninth aspect or the ninth aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the tenth aspect or the tenth aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the eleventh aspect or the eleventh aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the twelfth aspect or the twelfth aspect, or comprise instructions for carrying out the method of any one of the possible implementations of the thirteenth aspect or the thirteenth aspect.

In a seventeenth aspect, a computer program product is provided, the computer program product comprising: computer program code for causing a computer to perform the method of any one of the possible implementations of the first aspect or the first aspect described above, or to perform the method of any one of the possible implementations of the second aspect or the second aspect, or to perform the method of any one of the possible implementations of the third aspect or the third aspect, or to perform the method of any one of the possible implementations of the fourth aspect or the fourth aspect, or to perform the method of any one of the possible implementations of the fifth aspect or the fifth aspect, or to perform the method of any one of the possible implementations of the sixth aspect or the sixth aspect, or to perform the method of any one of the possible implementations of the seventh aspect or the seventh aspect, or to perform the method of any one of the possible implementations of the eighth aspect or the eighth aspect, when the computer program code runs on a computer, or performing a method of any one of the possible implementations of the ninth aspect or the ninth aspect, or performing a method of any one of the possible implementations of the tenth aspect or the tenth aspect, or performing a method of any one of the possible implementations of the eleventh aspect or the tenth aspect, or performing a method of any one of the possible implementations of the twelfth aspect or the twelfth aspect, or performing a method of any one of the possible implementations of the thirteenth aspect or the thirteenth aspect.

Drawings

Fig. 1 is a diagram of a communication system architecture provided by an embodiment of the present application;

fig. 2 is a schematic diagram of an alien interference according to an embodiment of the present application;

fig. 3 is a schematic diagram of another alien interference according to an embodiment of the present application;

fig. 4 is a schematic diagram of generating an OFDM symbol according to an embodiment of the present application;

fig. 5 is a schematic diagram of frequency domain correlation detection provided in the embodiment of the present application;

FIG. 6 is a schematic diagram illustrating a failure of the cycling behavior provided by an embodiment of the present application;

fig. 7A is a schematic diagram of a 1 st OFDM symbol according to an embodiment of the present application;

fig. 7B is a schematic diagram of a 2 nd OFDM symbol according to an embodiment of the present application;

fig. 7C is a schematic diagram of two adjacent OFDM symbols satisfying a cyclic characteristic according to an embodiment of the present application;

fig. 7D is a schematic diagram of three consecutive OFDM symbols satisfying a cyclic characteristic according to an embodiment of the present application;

fig. 7E is a schematic diagram of two adjacent OFDM symbols satisfying a cyclic characteristic according to an embodiment of the present application;

fig. 8 is a schematic diagram illustrating a relationship between RSs carried on different OFDM symbols according to an embodiment of the present disclosure;

fig. 9A is a time domain diagram of a first basic resource structure for carrying a reference signal according to an embodiment of the present application;

fig. 9B is a time domain diagram of a reference signal carried by a second basic resource structure according to an embodiment of the present application;

fig. 9C is a time domain diagram of a reference signal carried by a third basic resource structure according to the embodiment of the present application;

FIG. 10 is a schematic diagram illustrating the corruption of the cyclic nature between the underlying resources provided by an embodiment of the present application;

fig. 11 is a schematic diagram of two adjacent basic resources satisfying a cyclic characteristic according to an embodiment of the present application;

fig. 12 is a schematic diagram of two adjacent basic resources satisfying a cyclic characteristic according to an embodiment of the present application;

fig. 13 is a schematic time domain and frequency domain diagram of a basic resource-bearing reference signal according to an embodiment of the present application;

fig. 14 is a schematic diagram illustrating a relationship between RSs carried on different basic resources according to an embodiment of the present application;

FIG. 15 is a flow chart of a method provided by an embodiment of the present application;

fig. 16 is a schematic diagram of a transceiving time configuration according to an embodiment of the present application;

fig. 17 is a schematic diagram illustrating normal and abnormal RS transmissions according to an embodiment of the present application;

fig. 18 is a schematic diagram of a timing relationship between a reference signal transmitted by a base station 1 and a reference signal detected by a base station 2 according to an embodiment of the present application;

FIG. 19 is a flow chart of another method provided by embodiments of the present application;

fig. 20A is a schematic diagram of a resource occupation location by reference signals according to an embodiment of the present application;

fig. 20B is a schematic diagram of another resource occupation location of a reference signal according to an embodiment of the present application;

fig. 20C is a schematic diagram of a resource location corresponding to reference signal transceiving according to an embodiment of the present application;

FIG. 21A is a schematic diagram of an apparatus according to an embodiment of the present disclosure;

fig. 21B is a schematic structural diagram of a network device according to an embodiment of the present application;

fig. 22 is a schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

The embodiment of the present application may be applied to, but not limited to, a 5G system, such as an NR system, an LTE system, a long term evolution-advanced (LTE-a) system, an enhanced long term evolution-advanced (LTE) communication system, and the like, and may also be extended to a related cellular system, such as wireless fidelity (WiFi), worldwide interoperability for microwave access (wimax), and 3 GPP. Specifically, as shown in fig. 1, the communication system architecture applied in the embodiment of the present application may include at least two network devices, which are a network device 1 and a network device 2, respectively, where the network device 1 serves the terminal device 1, and the network device 2 serves the terminal device 2. Network device 1 and network device 2 may be network devices that are geographically remote. It should be noted that, in the embodiment of the present application, the number of terminal devices and network devices in the communication system shown in fig. 1 is not limited.

Hereinafter, some terms in the present application are explained to facilitate understanding by those skilled in the art.

1) A network device is a device for accessing a terminal to a wireless network in a communication system. The network device is a node in a radio access network, which may also be referred to as a base station, and may also be referred to as a Radio Access Network (RAN) node (or device). In the following description, a base station will be referred to as an example. Currently, some examples of network devices are: a gbb, a Transmission Reception Point (TRP), an evolved Node B (eNB), a Radio Network Controller (RNC), a Node B (NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a home base station (e.g., home evolved Node B, or home Node B, HNB), a Base Band Unit (BBU), or a wireless fidelity (Wifi) Access Point (AP), etc. In addition, in a network structure, the network device may include a Centralized Unit (CU) node and a Distributed Unit (DU) node. The structure separates the protocol layers of the eNB in a Long Term Evolution (LTE) system, the functions of part of the protocol layers are centrally controlled by the CU, the functions of the rest part or all of the protocol layers are distributed in the DU, and the DU is centrally controlled by the CU.

2) A terminal, also referred to as a terminal device, a User Equipment (UE), a Mobile Station (MS), a Mobile Terminal (MT), etc., is a device for providing voice and/or data connectivity to a user, for example, a handheld device with a wireless connection function, a vehicle-mounted device, etc. Currently, some examples of terminals are: a mobile phone (mobile phone), a tablet computer, a notebook computer, a palm top computer, a Mobile Internet Device (MID), a wearable device, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in self driving (self driving), a wireless terminal in remote surgery (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (transportation safety), a wireless terminal in city (smart city), a wireless terminal in smart home (smart home), and the like.

3) Heterointerference (CLI):

the CLI between base stations mainly means that a Downlink (DL) signal transmitted by one base station interferes with an Uplink (UL) signal of another base station, and the uplink signal may be a signal transmitted to the base station by the UE, for example. Referring to fig. 2, left and right cells belonging to two base stations operate in the same frequency band, the left cell belongs to a first base station, and the right cell belongs to a second base station. In the left cell, the first base station is transmitting DL signals to the UE1, while in the right cell, the second base station is receiving UL signals transmitted by the UE2, but the DL signals transmitted by the first base station can also be received by the second base station, so the downlink signals of the left cell interfere with the reception of the right cell.

CLI between base stations typically occurs in situations where the transmission directions of two TDD cells operating at the same frequency are different. Therefore, if the TDD cell keeps the transmission direction the same, CLI is not usually generated. There are exceptions, however: two base stations located far apart from each other in geographical position, even if their transmission directions are the same (i.e. receiving uplink/simultaneously transmitting downlink signals), due to the far geographical position, a significant time delay is passed when the downlink signal transmitted from one base station reaches another base station, and the other base station has switched from the downlink transmission direction to the uplink reception direction, thereby generating CLI, as shown in fig. 3: a time delay occurs when a downlink signal transmitted by the base station 1 arrives at the base station 2, and the CLI is generated when the base station 2 is receiving an uplink signal.

4) Cyclic shift:

the cyclic shift is to use the bits of the original range before the shift as the complementary bits of the other end without losing the bits at the time of the shift. For example, taking the left cyclic shift as an example, the sequence a is 123456, and the sequence B after the sequence a is two-bit cyclic shifted is: and B is 345612. Taking the cyclic right shift as an example, the sequence C after the sequence a performs two-bit cyclic shift is: and C is 561234. That is, when the sequence x (N), N ═ 0,1,2, …, and N-1 are subjected to cyclic left shift of K bits to obtain the sequence y (N), x (N) and y (N) satisfy y (N) ═ x (N + K)_NN-0, 1,2, …, N-1, where x (N)_NRepresents the period extension of x (n). Without loss of generality, "left" may denote "earlier/earlier in time" and "right" may denote "later/later in time" for sequences with chronological precedence; for example, the sequence a ═ 123456, since "1" is to the left of "2", 1 is earlier than 2.

5) An orthogonal frequency division system:

an Orthogonal Frequency Division Multiplexing (OFDM) communication system belongs to a multi-carrier system. In the frequency domain, one OFDM symbol occupies a plurality of orthogonal subcarriers (subcarriers). In the time domain, one OFDM symbol includes a plurality of sampling points (samples), also called sampling points; the signal carried by one OFDM symbol is a signal obtained by superimposing N orthogonal subcarrier signals. An OFDM symbol is usually generated by first carrying a signal to be transmitted in a frequency domain, and then converting the signal into a time domain by inverse fourier transform; the OFDM symbol converted into the time domain also needs to add a Cyclic Prefix (CP), that is, several sampling points at the end are added to the head end as the CP to form an OFDM symbol containing the CP, as shown in fig. 4. One square in the time domain sequence in fig. 4 represents one or more subcarriers and one square in the time domain sequence represents one or more samples.

In order to combat the CLI existing between the base stations at an ultra-long distance, the measurement between the base stations is firstly needed, and in NR, the reference signal for the measurement of the channel condition between the NR base stations is not standardized at present, and the related measurement process is not standardized.

The applicant has found that if ultra-long distance measurement between base stations is to be performed, the problem of uncertainty of the arrival time between Reference Signals (RS) needs to be considered. This is because the distance between the base stations where the super-far interference occurs is not constant, and therefore, the time when the RS transmitted from the base station 1 reaches the base station 2 is not determined. Due to the uncertainty of the RS time delay, one base station can only detect the reference signal by a blind detection method. If the correlation detection is carried out in the time domain, the time domain sliding correlation window detection needs to be carried out on sampling points one by one, the convolution calculation needs to be carried out on the position of each sampling point, and the calculation cost is very high. And the correlation detection in the frequency domain can obtain the correlation calculation results corresponding to a plurality of sampling points at one time through Fourier transform, frequency domain point multiplication and inverse Fourier transform, so the complexity of the frequency domain correlation detection is low, and the frequency domain correlation detection is more advantageous for the measurement between the base stations. The frequency domain correlation detection needs to ensure that at least one complete sample to be detected can be observed in a detection window in the time domain, and the observed sample to be detected can be a sample to be detected after cyclic shift. Therefore, if the frequency domain correlation detection method is used to detect the reference signal, it should be ensured that the reference signal has the cyclic shift characteristic, that is, the reference signal may include a plurality of repeated portions, each portion is the same, and each portion is equivalent to a complete sample to be detected. Mathematically, for a sequence x (N) of a loop of total length N, x (N) ═ x (N + K) should be satisfied, where N ═ 0,1,2, …, N-K-1, and K is a constant associated with the loop characteristics, such as the length of each segment. The reference signal may be determined to be detected when at least one of the at least repeated portions is detected in the detection window.

For example, if the detection window is one OFDM symbol long and the reference signal includes a repeated portion that is also one OFDM symbol long, it is required that the reference signals carried in consecutive OFDM symbols are the same. As shown in fig. 5, the base station 2 performs frequency domain correlation detection on the RS transmitted by the base station 1. According to the characteristics of frequency domain correlation detection, the RSs carried in consecutive OFDM symbols transmitted by the base station 1 are the same, and the cyclic characteristics are guaranteed. In fig. 5, as an example, it is assumed that the detection window is 1 OFDM symbol long, and the RS occupies 2 consecutive OFDM symbols.

In order to achieve that at least one complete RS is included in the detection window, one possible design is to make the RS carried by two consecutive OFDM symbols before and after the same.

However, carrying the same RS directly on the two previous OFDM symbols would destroy the cyclic characteristics due to the addition of the respective CP on each OFDM symbol. For example, referring to fig. 6, different padded symbols respectively represent a first OFDM symbol and a second OFDM symbol, and the two former OFDM symbols and the latter OFDM symbols both carry the same RS, i.e. 12345678 as viewed from the time domain. However, after each OFDM symbol is added with CP, the transmitted RS is in the form of "78-12345678-78-12345678", which is cyclic only in one OFDM symbol (i.e. in the form of 78-12345678), but it is not cyclic between two OFDM symbols, and the cyclic characteristic between two OFDM symbols needs to be guaranteed to have the form of "12345678 + 12345678". Because the cyclic characteristic is destroyed, the receiving end cannot effectively carry out blind detection by a frequency domain correlation method.

Based on this, embodiments of the present application provide a method and an apparatus for transmitting and receiving a reference signal, so as to solve the problem in the prior art that channel measurement cannot be performed between two remote base stations. The method and the device are based on the same inventive concept, and because the principles of solving the problems of the method and the device are similar, the implementation of the device and the method can be referred to each other, and repeated parts are not described again.

The base station 1 at the transmitting end may carry the reference signal over multiple symbols to the base station 2 at the receiving end, for example, the base station 1 may carry the reference signal over M consecutive OFDM symbols to transmit.

The continuity referred to herein means continuity in the time domain. In addition, on one hand, the OFDM symbol referred to in the embodiment of the present application may be an OFDM symbol to which a CP is added, and on the other hand, the OFDM symbol may also be an OFDM symbol to which a Cyclic Suffix (CS) is added.

The following describes the relationship between reference signals respectively carried by M consecutive OFDM symbols in the time domain and the frequency domain.

First, taking an OFDM symbol with CP added as an example, the following description will be made in terms of the time domain:

in the time domain, in M consecutive OFDM symbols, the reference signal carried by the portion of the first OFDM symbol excluding the CP is the same as the signal obtained by performing W long cyclic shift on the reference signal carried by the portion of the second OFDM symbol excluding the CP. The first and second OFDM symbols are any two of the M consecutive OFDM symbols.

If the first OFDM symbol is later than the second OFDM symbol in the time domain, the cyclic shift is a cyclic left shift, and W may be determined according to the CP length of the OFDM symbol spaced between the first OFDM symbol and the second OFDM symbol and the CP length of the first OFDM symbol.

If the first OFDM symbol is earlier in time domain than the second OFDM symbol, the cyclic shift is a cyclic right shift, and W may be determined according to a CP length of an OFDM symbol spaced from the first OFDM symbol and the second OFDM symbol and a CP length of the second OFDM symbol.

In a possible example, the first OFDM symbol and the second OFDM symbol are two adjacent OFDM symbols in the time domain, and then the two adjacent OFDM symbols, in the time domain, the reference signal carried by the portion of the latter OFDM symbol from which the CP is removed is the same as the signal obtained by cyclically shifting (cyclically left-shifting) the reference signal carried by the portion of the former OFDM symbol from which the CP is removed, and the length of the cyclic shift is determined by the CP length of the OFDM symbol.

Illustratively, the CP length of the OFDM symbol is a CP length of a latter OFDM symbol of the two adjacent OFDM symbols.

Wherein, the latter and former refer to the time before and after.

If the length of the CP from the second OFDM symbol to the mth OFDM symbol in the M OFDM symbols is the same, for example, all the CP lengths are L, the length of the cyclic shift performed on the reference signal carried by the portion of the previous OFDM symbol from which the CP is removed is L, that is, the signal obtained by cyclically shifting (cyclically left shifting) the L bit of the reference signal carried by the portion of the previous OFDM symbol from which the CP is removed is the same as the reference signal carried by the portion of the next OFDM symbol from which the CP is removed.

In another possible example, in M consecutive OFDM symbols, a reference signal carried by the part of the u-th OFDM symbol excluding the CP is the same as a signal obtained by performing (u-v) · L long cyclic shift on a reference signal carried by the part of the v-th OFDM symbol excluding the CP, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and L is a CP length of the OFDM symbol. For example, when v is 1, the reference signal carried by the part of the u-th OFDM symbol excluding the CP is the same as a signal obtained by performing (u-1) · L long cyclic shift (cyclic left shift) on the reference signal carried by the part of the 1-th OFDM symbol excluding the CP, and the CP lengths of the 2 nd to M-th OFDM symbols are all L.

In addition toIn one possible example, in the M consecutive OFDM symbols, the reference signal carried by the part of the u-th OFDM symbol excluding the CP is performed with the reference signal carried by the part of the v-th OFDM symbol excluding the CP

Signals obtained by long cyclic shift are the same, Ln is the CP length of the nth OFDM symbol, u is an integer which is greater than 1 and less than or equal to M, and v is an integer which is greater than or equal to 1 and less than u. For example, when v is 1, the reference signal carried by the CP-removed part of the u-th OFDM symbol is performed with the reference signal carried by the CP-removed part of the 1 st OFDM symbol

The signals resulting from a long cyclic shift (cyclic left shift) are identical.

The following description will be made in terms of time domain, taking CS-added OFDM symbols as an example:

in the time domain, in M consecutive OFDM symbols, the reference signal carried by the portion of the first OFDM symbol excluding CS is the same as the signal obtained by performing W long cyclic shift on the reference signal carried by the portion of the second OFDM symbol excluding CS. The first and second OFDM symbols are any two of the M consecutive OFDM symbols.

If the first OFDM symbol is later than the second OFDM symbol in the time domain, the cyclic shift is a cyclic left shift, and W may be determined according to a CS length of an OFDM symbol spaced between the first OFDM symbol and the second OFDM symbol and a CS length of the second OFDM symbol.

If the first OFDM symbol is earlier in time domain than the second OFDM symbol, the cyclic shift is a cyclic right shift, and W may be determined according to a CS length of an OFDM symbol spaced between the first OFDM symbol and the second OFDM symbol and the CS length of the first OFDM symbol.

In a possible example, the first OFDM symbol and the second OFDM symbol are two adjacent OFDM symbols in the time domain, and then the two adjacent OFDM symbols, in the time domain, a part of the reference signal carried by the latter OFDM symbol except the CS is the same as a signal obtained by cyclically shifting (cyclically left shifting) a part of the reference signal carried by the former OFDM symbol except the CS, and the length of the cyclic shift is determined by the CS length of the OFDM symbol.

Illustratively, the CS length of the OFDM symbol is the CS length of the previous OFDM symbol in the two adjacent OFDM symbols.

If the length of CS from the first OFDM symbol to the M-1 th OFDM symbol in the M OFDM symbols is the same, for example, all CS lengths are L, the length of cyclic shift performed on the reference signal carried by the part of the previous OFDM symbol excluding CS is L, that is, the signal obtained by cyclic shift (cyclic left shift) L of the reference signal carried by the part of the previous OFDM symbol excluding CS is the same as the reference signal carried by the part of the next OFDM symbol excluding CS.

In another possible example, in M consecutive OFDM symbols, a cyclic shift (u-v) · L long is performed on the reference signal carried by the u-th OFDM symbol except for the CS portion and the reference signal carried by the v-th OFDM symbol except for the CS portion to obtain the same signal, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and L is the CS length of the OFDM symbol. For example, when v is 1, the reference signal carried by the u-th OFDM symbol excluding CS is the same as a signal obtained by performing (u-1) · L long cyclic shift (cyclic left shift) on the reference signal carried by the 1-th OFDM symbol excluding CS, and the CS lengths of the 2 nd to M-th OFDM symbols are all L.

In yet another possible example, the reference signal carried by the CS-removed part of the u-th OFDM symbol is performed with the reference signal carried by the CS-removed part of the v-th OFDM symbol in the M consecutive OFDM symbols

The signals obtained by the long cyclic shift are the same, Ln is the CS length of the nth OFDM symbol, u is an integer greater than 1 and less than or equal to M, and v is an integer greater than or equal to 1 and less than u. For example, when v is 1, the reference signal carried by the part of the u-th OFDM symbol excluding CS is performed with the reference signal carried by the part of the 1 st OFDM symbol excluding CS

In the following, taking the 1 st OFDM symbol and the 2 nd OFDM symbol of M OFDM symbols including the CP as an example, it will be described that any two OFDM symbols satisfy the cyclic characteristic by cyclic shift.

For example, the 1 st OFDM symbol is x₁(N) the length when no CP is included is N, then after it is added with an L-long CP, it will satisfy the N-point cyclic shift characteristic in the range of N-0, 1,2, …, L-1, that is, satisfy the condition shown in formula (1):

x₁(n)＝x₁(n+N)，n＝0,1,2,…,L-1 (1)

as shown in fig. 7A, N is 8 as an example.

The 2 nd OFDM symbol is x₂(m) the length when CP is not included is N, then after it is added with L long CP, it will satisfy N-point cyclic shift characteristics in the range of

m

0,1,2, …, L-1, that is, satisfy the condition shown in formula (2):

x₂(m)＝x₂(m+N)，m＝0,1,2,…,L-1 (2)

as shown in fig. 7B, N is 8.

By concatenating the 1 st OFDM symbol (including CP) with the 2 nd OFDM symbol (including CP) in the time domain, the 2 nd OFDM symbol follows the 1 st OFDM symbol, we can get N ═ N + L, N + L +1, N + L +2, …,2N +2L-1 with x in the range₁(N) and m ═ 0,1,2, …, x in the range of N + L-1₂(m) that satisfies the condition shown in formula (3):

x₁(n)＝x₂(n-N-L)，n＝N+L,N+L+1,N+L+2,…,2N+2L-1 (3)

within the 1 st and 2 nd OFDM symbols, x₁(N) the condition that the cycle characteristic of N points is satisfied is shown in formula (4):

x₁(n)＝x₁(n+N)，n＝0,1,2,…,L-1,L,L+1,L+2,…,N+2L-1 (4)

in the formula (4), N is selected from the range of 0,1,2, …, L-1, L +1, L +2, …, and N + 2L-1. Combining equation (3) and equation (4), equation (5) can be derived:

x₂(n)＝x₁(n+N+L)＝x₁(n+L)，n＝0,1,2,…,N+L-1 (5)

equation (5) embodies x₁(n) and x₂(n) in the above formula (I). But further, consider x₁(n) and x₂Since (N) is actually a sequence defined as N long and L is the number of points to which a CP is added, it is necessary to obtain x in a range defined by N-0, 1,2, … N-1 (or N-L, L +1, … L + N-1, both of which are equivalent) as well₁(n) and x₂(n) in the above formula (I). Further, combining formula (1), formula (2), and formula (5), formula (6) can be obtained:

as can be seen from equation (6), x₁(n) and x₂(N) the sequences obtained after the connection still meet the condition of N-point cycle characteristics: x is the number of₂(n) sequences obtained by cyclic shift of L points and x₁(n) are the same.

Illustratively, as shown in FIG. 7C, when x₁(n) and x₂After (N) concatenation, x is used to ensure that the sequence as a whole still satisfies the cyclic property of N points (N is 8 in fig. 7C)₂(n) "12345678" needs to be equal to x₁"34567812" of (n), corresponding to x₂(n) sequences obtained by cyclic shifting of L points of the part not including CP and x₁The same applies to the portion excluding CP in (n) (fig. 7C illustrates L as 2).

The above conclusion can also be extended to the case where the reference signal is mapped onto multiple symbols, as shown in fig. 7D, taking three symbols as an example: when x is₁(n)、x₂(n) and x₃After (N) concatenation, x is used to ensure that the sequence as a whole still satisfies the cyclic property of N points (N is 8 in fig. 7D)₂(n) "12345678" needs to be equal to x₁"34567812" of (n) corresponds to x₂(n) sequences obtained by cyclic shift of L points and x₁(n) the same (fig. 7D, for example, L ═ 2); x is the number of₃(n)' 12345678 "needs to be equal to x₂"34567812" of (n) corresponds to x₃(n) sequences obtained by cyclic shifting of L points of the part not including CP and x₂The portion of (n) not including CP is the same, while x₃(n) "12345678" also equals x₁"56781234" of (n) corresponds to x₃(n) sequence obtained by cyclic shift of 2L points on part not including CP and x₁The same applies to the portion of (n) excluding CP.

As an example, referring to FIG. 7E, two reference signal sequences added with CS are x respectively₄(n) and x₅(n)，x₄(n) is "1234567812" if x₄(n) and x₅(N) after connection, in order to ensure that the sequence as a whole meets the cyclic characteristic of N points, N is the length of two reference signal sequences without adding CS, and x₅(n) should be "3456781234".

The following description is made in the frequency domain:

in terms of frequency domain, in the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is determined by an index of the first subcarrier, where the first OFDM symbol and the second OFDM symbol are any two of the M consecutive OFDM symbols, and M is an integer greater than or equal to 2. It should be noted that one OFDM symbol occupies multiple subcarriers in the frequency domain, and the number of occupied subcarriers is related to the system bandwidth. The first subcarrier occupies any one subcarrier of a plurality of subcarriers in a frequency domain for one OFDM symbol.

For an OFDM multi-carrier system such as NR and LTE, it is possible that not only RS but also data to be sent to UE need to be carried on one OFDM symbol, that is, for the base station 1, the RS sent to the base station 2 and the data sent to the UE served by itself are carried on different subcarriers of the same OFDM symbol. If the second OFDM symbol is directly cyclically shifted in the time domain, it may cause the terminal device to perform inaccurate estimation on its downlink channel, and fail to correctly receive and demodulate the data on the cyclically shifted OFDM symbol. Therefore, by the frequency domain adjusting means provided in the embodiment of the present application, on the premise of ensuring that RSs of M OFDM symbols can be correctly detected, the reception of data thereof is not affected.

The cyclic shift of the OFDM signal in the time domain may appear in the frequency domain as a phase offset of a corresponding frequency domain signal (i.e., a phase difference between reference signals carried by two OFDM symbols on the same subcarrier), and the phase offset between the reference signals carried by the same subcarrier of the two OFDM symbols is determined according to an index of the subcarrier. For a complex number Ae^iθI represents

Theta is its phase. The phase of a complex number is usually considered to be its value in the interval 0-2 pi, i.e. the value of θ modulo 2 pi (θ mod 2 pi), since for a complex number a phase of θ and a phase of (θ +2 pi) are equivalent. The phase shift amount (phase difference) is proportional to the variation of the subcarrier k, that is, the phase difference is linear with the index k of the subcarrier.

The linear relationship between the phase difference value w of the reference signal carried by the subcarrier k by the two OFDM symbols and the subcarrier index k is represented by a relationship between the phase difference values w and k in a linear function, for example, w ═ Ak + C, where a and C are constants independent of k. Illustratively, of the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is w1, a phase difference between a phase of a reference signal carried on a second subcarrier of the first OFDM symbol and a phase of a reference signal carried on a second subcarrier of the second OFDM symbol is w2, a phase difference between a phase of a reference signal carried on a third subcarrier of the first OFDM symbol and a phase of a reference signal carried on a third subcarrier of the second OFDM symbol is w3, the phase difference between the phase of the reference signal carried on the fourth subcarrier of the first OFDM symbol and the phase of the reference signal carried on the fourth subcarrier of the second OFDM symbol is w 4; if the difference between the index of the second subcarrier and the index of the first subcarrier is equal to the difference between the index of the fourth subcarrier and the index of the third subcarrier, the value of (w2-w1) modulo 2 pi is equal to the value of (w4-w3) modulo 2 pi.

In one possible implementation, for an OFDM symbol containing a CP, the phase difference between the phase of the reference signal carried on the first subcarrier of the first OFDM symbol and the phase of the reference signal carried on the first subcarrier of the second OFDM symbol is also determined by the symbol length of the OFDM symbol and/or the cyclic prefix CP length of the OFDM symbol.

For OFDM symbols containing CS, the phase difference between the phase of the reference signal carried on the first subcarrier of the first OFDM symbol and the phase of the reference signal carried on the first subcarrier of the second OFDM symbol is also determined by the symbol length of the OFDM symbol and/or the CS length of the OFDM symbol.

Exemplarily, taking an OFDM symbol including a CP as an example, the first OFDM symbol is separated from the second OFDM symbol by X OFDM symbols, the first OFDM symbol is earlier than the second OFDM symbol in the time domain, and X is an integer greater than or equal to 0; the CP length of the OFDM symbol is determined by the CP lengths of the X OFDM symbols and the CP length of a second OFDM symbol. For example, the first OFDM symbol is adjacent to the second OFDM symbol, and the CP length of the OFDM symbol is the CP length of the second OFDM symbol. For example, the first OFDM symbol is separated from the second OFDM symbol by 2 OFDM symbols, and the CP length of the OFDM symbol is determined according to the CP lengths of the separated 2 OFDM symbols and the CP length of the second OFDM symbol. One possible method is that the phase difference is determined by the sum of the CP length of the 2 spaced OFDM symbols and the CP length of the second OFDM symbol.

In another possible implementation manner, for an OFDM symbol including a CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a next OFDM symbol and a phase of a reference signal carried on a first subcarrier of a previous OFDM symbol of any two adjacent OFDM symbols among the M consecutive OFDM symbols is 2 pi Lk/N, where N is a symbol length of the OFDM symbol, L is a CP length of the OFDM symbol, and k is an index of the first subcarrier. Illustratively, L is the CP length of the latter OFDM symbol. Where the length N does not include part of the CP.

For an OFDM symbol including CS, in any two adjacent OFDM symbols of the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a next OFDM symbol and a phase of a reference signal carried on a first subcarrier of a previous OFDM symbol is 2 pi Lk/N, where N is a symbol length of the OFDM symbol, L is a CS length of the OFDM symbol, and k is an index of the first subcarrier. Illustratively, L is the CS length of the previous OFDM symbol. Where the length N does not include a portion of CS.

In yet another possible implementation manner, for the OFDM symbol including the CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th OFDM symbol and a phase of a reference signal carried on a first subcarrier of a v-th OFDM symbol in the M consecutive OFDM symbols is

For the OFDM symbol containing CS, in the M continuous OFDM symbols, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th OFDM symbol and the phase of the reference signal carried on the first subcarrier of the v-th OFDM symbol is

Wherein N is a symbol length of the OFDM symbol, Ln is a CS length of the nth OFDM symbol, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

Exemplarily, taking an OFDM symbol including a CP as an example, if v is 1, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th OFDM symbol and a phase of a reference signal carried on a first subcarrier of a 1-th OFDM symbol is represented by

For example, in the M consecutive OFDM symbols, the CP lengths of the 2 nd to M th OFDM symbols are equal and all L, and the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th OFDM symbol and the phase of the reference signal carried on the first subcarrier of the v-th OFDM symbol is

For example, in the M consecutive OFDM symbols, the CP lengths of the 2 nd to M th OFDM symbols are equal and all L, and the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th OFDM symbol and the phase of the reference signal carried on the first subcarrier of the 1 st OFDM symbol is

I.e., 2 π (u-1) Lk/N.

According to the nature of the OFDM system, the cyclic shift of an OFDM signal in the time domain will appear in the frequency domain as a phase offset of the corresponding frequency domain signal (i.e. a phase difference between reference signals carried by two OFDM symbols on the same subcarrier), the phase offset being determined according to the index of the subcarrier, in other words, the cyclic shift of an OFDM signal in the time domain will appear in the frequency domain as a linear phase sequence linearly related to the subcarrier index k by multiplying the corresponding frequency domain signal point by a phase sequence. Taking OFDM symbols containing CP as an example, the corresponding derivation is as follows:

let y (n) be an L-point cyclic shift sequence of the x (n) sequence, then y (n) satisfies equation (7):

y(n)＝x(n+L)_NR_N(n) (7)

wherein, x (n + L)_NRepresents a cyclic extension sequence of x (n) sequence shifted by L points, R_NAnd (N) represents a window function with the length of N, so that the sequence obtained by circularly shifting y (N) and x (N) through L points can be represented to be the same. Note X [ k ]]Represents x (n) a frequency domain signal after being spread by fourier transform in the frequency domain, as shown in equation (8):

equation (8) is the principle of OFDM systems, i is

k is in the range of 0,1,2, … N-1. For example, Y [ k ]]Represents y (n) a frequency domain signal after fourier transform expansion in the frequency domain, as shown in equation (9):

let n + L be n', then equation (9) may further become equation (10):

due to x (n')_NIs a periodic sequence, thus x (n')_NIn the interval [ L, L +1, …, N + L-1]Integral over (i.e. sum) with x (n')_NIn the interval [0,1, …, N-1]Is the same, so there are:

thus, as can be seen from the above equation (11), the phase difference of the reference signals carried by the two OFDM symbols on the subcarrier with index k is determined by the subcarrier k and also by the symbol length N (i.e. fourier transform) of the OFDM symbolPoints exchanged) and L. For cyclic shift between two adjacent OFDM negative signs caused by CP, the length L of the cyclic shift is the CP length of the OFDM symbol. And, the phase difference of the reference signals carried by the two OFDM symbols on the subcarrier with the index of k is

It increases linearly with the index k of the subcarrier. The phase difference can also be seen as a line that varies with k and has a slope of 2 pi L/N.

That is, if an RS signal is carried on each OFDM symbol in a plurality of consecutive OFDM symbols, and the RS carried on the kth subcarrier of the 1 st OFDM symbol is s (k), the RS carried on the subcarrier k for the 2 nd OFDM symbol should be s (k) multiplied by a complex compensation quantity, the phase of which is

I.e. the complex compensation amount is

For the No. 3, No. 4, No. … … Mth OFDM symbol, the phase of the complex compensation quantity needed to be multiplied by the RS carried on the subcarrier k on the Mth OFDM symbol is

Ln is the length of CP corresponding to the nth OFDM symbol; if the length of the CP from the 2 nd OFDM symbol to the mth OFDM symbol is L, the phase of the complex compensation quantity to be multiplied by the RS carried on the subcarrier k on the mth OFDM symbol is L

That is, the phase compensation amount corresponding to the reference signal carried on the subcarrier k from the 2 nd OFDM symbol to the mth OFDM symbol has the phase

Therefore, for the base station sending the reference signal, the linear phase compensation can be performed on the reference signal loaded on different OFDM symbols on the frequency domain, so that the effect equivalent to the time domain cyclic shift is realized; the base station transmitting the reference signal transmits the reference signal so that the base station receiving the reference signal can detect the reference signal in a frequency domain correlation manner. The sending base station may generate a reference signal carried on one OFDM symbol first, and then generate reference signals carried on other OFDM symbols according to a relationship between reference signals between different OFDM symbols in a time domain/frequency domain in the embodiment of the present application, or the sending base station may directly generate reference signals carried on multiple OFDM symbols according to a relationship between reference signals between different OFDM symbols in a time domain/frequency domain in the embodiment of the present application, or generate reference signals in other manners, which is not limited in the present application.

For example, taking an OFDM symbol occupying 8 subcarriers, as shown in fig. 8, RSs carried on 8 subcarriers of the 1 st OFDM are S (0), S (1), S (2), …, and S (7), respectively. By the scheme provided by the embodiment of the present application, the RSs carried on 8 subcarriers of the 2 nd OFDM symbol are S (0) × exp (i × 0 × 2 × L/N), S (1) × exp (i × 1 × 2 × L/N), S (2) × exp (i × 2 pi L/N), …, S (7) × exp (i × 7 × 2 pi L/N), and the RSs carried on 8 subcarriers of the 3 rd OFDM symbol are S (0) × exp (i × 2 × 0 pi L/N), S (1) × (i 2 × 1 pi L/N), S (2) × (i × 2 pi L/N), S (7) × 2 × 3 pi L/N, S (7) × 2 × 3 × L/N, respectively. Wherein exp (x) represents e^x。

It should be noted that, the above is based on the previous OFDM symbol, and the RS of the next OFDM symbol is dot-by-dot multiplied by one in the frequency domain

Linear phase of "is described, but it can also be based on the next OFDM symbol, and the RS of the previous OFDM symbol is dot-multiplied by one in the frequency domain

Linear phase "of the OFDM symbol is substantially the same, i.e. two adjacent OFDM symbols have k-indexed subcarriersThe phase difference between RS on the wave is

In the embodiments of the present application, the scheme provided by the embodiments of the present application is described in terms of symbols carrying reference signals, and as described in the foregoing embodiments, the following is described in terms of basic resources formed by a plurality of OFDM symbols carrying reference signals. The base station 1 at the transmitting end may transmit the reference signal to the base station 2 at the receiving end on a plurality of basic resources.

In this embodiment of the present application, resources used for carrying RSs measured between base stations include one or more basic resources, each basic resource includes Y consecutive third OFDM symbols (the third OFDM symbols do not include a CP or a CS) in a time domain, and Y is an integer greater than or equal to 2; the RS carried by each third OFDM symbol in one basic resource is the same. The time domain length of one basic resource is equal to the length of Y fourth OFDM symbols including the CP. The fourth OFDM symbol in the embodiment of the present application denotes an OFDM symbol including a CP and/or a CS. And the third OFDM symbol is an OFDM symbol excluding the CP and the CS.

Illustratively, the third OFDM symbol and the fourth OFDM symbol have the same symbol length, i.e., the third OFDM symbol and the fourth OFDM symbol excluding the CP and/or CS have the same length.

It should be understood that OFDM symbols, which are not explicitly described in the embodiments of the present application, all refer to OFDM symbols including CP and/or CS.

Alternatively, for convenience, the RS carried by one third OFDM symbol may be referred to as one RS time domain sequence in the time domain.

Each basic resource may include one CP and/or one CS, and thus, the basic resources may be divided into the following three structures.

The first basic resource structure: the basic resource only comprises the CP, the CP of the basic resource is at the forefront of the basic resource, and the CP length of the basic resource is equal to the sum of the CP lengths of the Y fourth OFDM symbols. For example, referring to fig. 9A, fig. 9A illustrates that the time domain length of the basic resource is equal to two fourth OFDM symbols. One basic resource includes two third OFDM symbols and one CP.

Second basic resource structure: the basic resource includes only CS, and the CS of the basic resource is at the last end of the basic resource, and the length of the CS of the basic resource is equal to the sum of the CP lengths of the Y fourth OFDM symbols. For example, referring to fig. 9B, the time domain length of the basic resource is equal to two fourth OFDM symbols in fig. 9B. One basic resource includes two third OFDM symbols and one CS.

The third basic resource structure: the basic resource comprises a CP and a CS, the CS of the basic resource is at the rearmost end of the basic resource, and the CP of the basic resource is at the foremost end of the basic resource. For example, as shown in fig. 9C, the time domain length of the basic resource is equal to two fourth OFDM symbols in fig. 9C. One basic resource includes two third OFDM symbols and one CP and one CS.

Because the RS time domain sequence carried by each third OFDM symbol in one basic resource is the same, the RS in one basic resource meets the cyclic characteristic on the time domain; however, in Z consecutive basic resources, even if the RS sequences carried are the same, the CP and/or CS in each basic resource are added separately, which destroys the overall cyclic characteristics. For example, taking a basic resource structure as an example, as shown in fig. 10, each basic resource includes multiple RS sequences and one CP, and each basic resource includes the same RS sequence, i.e., "12345678" as viewed from the time domain. After each basic resource is added with a CP, the transmitted RS is "5678 + 12345678", which is cyclic in one basic resource, but the RS "5678 + 12345678 + 5678 + 12345678" in the two basic resources is not cyclic, and the cyclic characteristics in the two basic resources need to ensure the form of "12345678 + 12345678". Because the cyclic characteristic between two basic resources is destroyed, when the detection window of the receiving end observes the RS between the two basic resources, the blind detection still cannot be effectively performed by the frequency domain correlation method.

Based on this, the scheme provided by the embodiment of the application can solve the problem that the cycle characteristics among a plurality of basic resources are damaged.

The base station 1 at the transmitting end may carry the reference signal on a plurality of basic resources and transmit the reference signal to the base station 2 at the receiving end, for example, the base station 1 carries the reference signal on Z consecutive basic resources and transmits the reference signal. The continuity referred to herein means continuity in the time domain. In addition, on one hand, the fourth OFDM symbol referred to in the embodiments of the present application may be an OFDM symbol to which a CP is added, and on the other hand, the fourth OFDM symbol may also be an OFDM symbol to which a Cyclic Suffix (CS) is added.

The following describes the relationship between the reference signals respectively carried by the Z consecutive basic resources in the time domain and the frequency domain.

First, taking the structure of the first basic resource as an example, that is, the basic resource including only the CP, the following is explained in terms of the time domain:

in the Z consecutive basic resources, the reference signal included in the first basic resource is identical to the signal obtained by performing W-long cyclic shift on the reference signal included in the second basic resource in terms of the time domain. The first and second basic resources are any two basic resources of the Z consecutive basic resources.

It should be understood that, a feasible understanding is that the reference signal carried by the basic resource in the embodiment of the present application refers to a reference signal carried by a symbol portion included in the basic resource, that is, a reference signal carried by Y third OFDM symbols included in the basic resource; in another feasible understanding, the reference signal carried by the basic resource in this embodiment refers to a reference signal carried by any one of Y third OFDM symbols included in the basic resource.

If the first basic resource is later than the second basic resource in the time domain, the cyclic shift is a cyclic left shift, and W may be determined according to the CP length of the basic resource between the first basic resource and the second basic resource and the CP length of the first basic resource.

If the first basic resource is earlier than the second basic resource in the time domain, the cyclic shift is a cyclic right shift, and W may be determined according to the CP length of the basic resource separated from the second basic resource by the first basic resource and the CP length of the second basic resource.

In a possible example, the first basic resource and the second basic resource are two adjacent basic resources in a time domain, and then, in the time domain, a reference signal carried by a subsequent basic resource is the same as a signal obtained by performing cyclic shift (cyclic left shift) on a reference signal carried by a previous basic resource by the two adjacent basic resources, and a length of the cyclic shift is determined by a CP length of the basic resource.

Illustratively, the CP length of the basic resource is the CP length of the latter basic resource of the two adjacent basic resources.

Wherein, the latter and former refer to the time before and after.

If the CP lengths from the second basic resource to the Z-th basic resource in the Z basic resources are the same, for example, all CP lengths are L, the length of the cyclic shift performed on the reference signal carried by the previous basic resource is L, that is, the signal obtained by cyclic shifting (cyclic left shift) the reference signal carried by the previous basic resource by L bits is the same as the reference signal carried by the next basic resource.

In another possible example, in Z consecutive basic resources, a reference signal carried by the u-th basic resource is the same as a signal obtained by performing (u-v) · L-long cyclic shift on a reference signal carried by the v-th basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and L is a CP length of the basic resource. For example, when v is 1, the reference signal carried by the u-th basic resource is the same as a signal obtained by performing (u-1) · L long cyclic shift (cyclic left shift) on the reference signal carried by the 1-th basic resource, and the CP lengths of the 2 nd to Z-th basic resources are all L.

In yet another possible example, in the Z consecutive basic resources, the reference signal carried by the u-th basic resource is performed with the reference signal carried by the v-th basic resource

Long cyclic shifted resulting signalSimilarly, Ln is the CP length of the nth base resource, u is an integer greater than 1 and less than or equal to Z, and v is an integer greater than or equal to 1 and less than u. For example, when v is 1, the reference signal carried by the u-th basic resource is performed with the reference signal carried by the 1 st basic resource

For example, referring to fig. 11, taking Z as 2, Y as 2, and L as 4 as an example, after the 2 nd basic resource is later than the 1 st basic resource, in order to ensure that the sequence still satisfies the cyclic characteristic after the 1 st basic resource and the 2 nd basic resource are connected, the RS time domain sequence of the 2 nd basic resource needs to be equal to the L as 4 point cyclic shift of the RS time domain sequence "12345678" of the 1 st basic resource, that is, "78156234". By the cyclic shift, the entirety of RSs included in the 1 st and 2 nd basic resources satisfy a cyclic characteristic in the time domain.

The above conclusion may also be extended to the case that the reference signal is mapped to multiple basic resources, and the application principle of the scheme of the present application is the same as that described above, and is not described herein again.

Next, taking the structure of the second basic resource as an example, that is, only the basic resource including CS, the following is explained from the time domain:

If the first basic resource is later than the second basic resource in the time domain, the cyclic shift is a cyclic left shift, and W may be determined according to the CS length of the second basic resource and the CS length of the interval between the first basic resource and the second basic resource.

If the first basic resource is earlier than the second basic resource in the time domain, the cyclic shift is a cyclic right shift, and W may be determined according to the CS length of the first basic resource and the CS length of the basic resource spaced between the first basic resource and the second basic resource.

In a possible example, the first basic resource and the second basic resource are two adjacent basic resources in a time domain, and then, in the time domain, a reference signal carried by a subsequent basic resource is the same as a signal obtained by cyclically shifting (cyclically left shifting) a reference signal carried by a previous basic resource by the two adjacent basic resources, and a length of the cyclic shift is determined by a CS length of the basic resource.

Illustratively, the CS length of the basic resource is the CS length of the previous basic resource in the two adjacent basic resources.

Wherein, the latter and former refer to the time before and after.

If the lengths of the CSs from the first basic resource to the Z-1 th basic resource in the Z basic resources are the same, for example, all the CSs are J, the length of the cyclic shift performed on the reference signal carried by the previous basic resource is J, that is, a signal obtained by cyclically shifting (cyclically left shifting) the J bit of the reference signal carried by the previous basic resource is the same as the reference signal carried by the next basic resource.

In another possible example, in Z consecutive basic resources, a reference signal carried by a u-th basic resource is identical to a signal obtained by cyclic shifting a reference signal carried by a v-th basic resource by a length of (u-v) · J, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and J is a CS length of the basic resource. For example, when v is 1, the reference signal carried by the u-th basic resource is the same as a signal obtained by performing cyclic shift (cyclic left shift) of (u-1) · J length on the reference signal carried by the 1 st basic resource, and the CS lengths of the 1 st to Z-1 st basic resources are all J.

Long cyclic shiftThe obtained signals are the same, Jn is the CS length of the nth basic resource, u is an integer which is greater than 1 and less than or equal to Z, and v is an integer which is greater than or equal to 1 and less than u. For example, when v is 1, the reference signal carried by the u-th basic resource and the reference signal carried by the 1 st basic resource are performed

Again, the structure of the third basic resource is taken as an example, that is, the basic resource including the CP and the CS is taken as an example, and the explanation is performed from the time domain:

If the first basic resource is later than the second basic resource in the time domain, the cyclic shift is a cyclic left shift, and W may be determined according to the CS length of the second basic resource, the CP length and the CS length of the basic resource spaced between the first basic resource and the second basic resource, and the CP length of the first basic resource.

If the first basic resource is earlier than the second basic resource in the time domain, the cyclic shift is a cyclic right shift, and W may be determined according to the CS length of the first basic resource, the CP length and CS length of the basic resource spaced between the first basic resource and the second basic resource, and the CP length of the second basic resource.

In a possible example, the first basic resource and the second basic resource are two adjacent basic resources in a time domain, and then, in the time domain, a reference signal carried by a subsequent basic resource is the same as a signal obtained by cyclically shifting (cyclically left shifting) a reference signal carried by a previous basic resource by the two adjacent basic resources, and a length of the cyclic shift is determined by a CP length and a CS length of the basic resource.

Illustratively, the CP length of the basic resource is a CP length of a subsequent basic resource in the two adjacent basic resources, and the CS length of the basic resource is a CS length of a previous basic resource in the two adjacent basic resources.

Wherein, the latter and former refer to the time before and after.

If, of the Z basic resources, the CP lengths from the second basic resource to the Z-th basic resource are the same, for example, are all L, and the CS lengths from the first basic resource to the Z-1 th basic resource are the same, for example, are all J, the length of the cyclic shift performed on the reference signal carried by the previous basic resource is L + J, that is, the signal obtained by cyclically shifting (cyclically left shifting) the L + J position of the reference signal carried by the previous basic resource is the same as the reference signal carried by the next basic resource.

In another possible example, in Z consecutive basic resources, a reference signal carried by the u-th basic resource is the same as a signal obtained by performing (u-v) · (L + J) long cyclic shift on a reference signal carried by the v-th basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, L is a CP length of the basic resource, and L is a CS length of the basic resource. For example, when v is 1, the reference signal carried by the u-th basic resource is the same as a signal obtained by performing (u-1) · (L + J) -long cyclic shift (cyclic left shift) on the reference signal carried by the 1 st basic resource, the CP lengths of the 2 nd to Z-th basic resources are all L, and the CS lengths of the 1 st to Z-1 th basic resources are all J.

The signals obtained by the long cyclic shift are the same, Ln is the CP length of the nth basic resource, Jn is the CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, and v is an integer greater than or equal to 1 and less than u. For example, when v is 1, the reference signal carried by the u-th basic resource and the reference carried by the 1 st basic resourceExamination signal proceeding

For example, referring to fig. 12, taking Z as 2, Y as 2, L as 2, and J as 2 as an example, the 2 nd basic resource is later than the 1 st basic resource, and after the 1 st basic resource and the 2 nd basic resource are connected, in order to ensure that the sequence as a whole still satisfies the cyclic characteristic, the RS time domain sequence of the 2 nd basic resource needs to be equal to the L + J of the RS time domain sequence "12345678" of the 1 st basic resource, that is, "56781234". By the cyclic shift, the entirety of the RSs included in the 1 st basic resource and the 2 nd basic resource satisfy the cyclic characteristic in the time domain.

The present application is explained above in the time domain, and the following is explained below in the frequency domain:

in terms of frequency domain, in Z consecutive basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is determined by an index of the first subcarrier, where the first basic resource and the second basic resource are any two basic resources of the Z consecutive basic resources, and Z is an integer greater than or equal to 2. It should be noted that one basic resource includes a plurality of third OFDM symbols, and one third OFDM symbol occupies a plurality of subcarriers in the frequency domain, where the number of occupied subcarriers is related to the system bandwidth. The first subcarrier occupies any subcarrier of a plurality of subcarriers for one third OFDM symbol in the frequency domain.

First, take the structure of the first basic resource as an example, that is, the basic resource includes CP and does not include CS. Fig. 13 shows a time domain and frequency domain diagram of a basic resource carrying reference signal. Exemplarily, Y ═ 2. RS frequency domain sequences are carried on subcarriers, for example, s (k) denotes RS carried on subcarrier k, k is 0,1, … …, 7. Since the reference signals carried on the plurality of third OFDM symbols included in one basic resource are all the same, the reference signal on the subcarrier k of one basic resource can be regarded as the reference signal on the subcarrier k of any one OFDM symbol in the basic resource.

In one possible implementation, for the basic resource containing the CP, a phase difference between a phase of a reference signal carried on the first subcarrier of the first basic resource and a phase of a reference signal carried on the first subcarrier of the second basic resource is further determined by a symbol length of the third OFDM symbol and/or a cyclic prefix CP length of the basic resource.

Exemplarily, taking a basic resource including a CP as an example, the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in a time domain, and X is an integer greater than or equal to 0; the CP length of the basic resource is determined by the CP lengths of the X basic resources and the CP length of a second basic resource. For example, the first basic resource is adjacent to the second basic resource, and the CP length of the basic resource is the CP length of the second basic resource. For example, the first basic resource is separated from the second basic resource by 2 basic resources, and the CP length of the basic resource is determined according to the CP lengths of the separated 2 basic resources and the CP length of the second basic resource. One possible method is that the phase difference is determined by the sum of the CP length of the 2 basic resources and the CP length of the second basic resource.

In another possible implementation manner, for the basic resource including the CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource of any two adjacent basic resources in the Z consecutive basic resources is 2 pi Lk/N, where N is a symbol length of the third OFDM symbol, L is a CP length of the basic resource, and k is an index of the first subcarrier. Illustratively, L is the CP length of the latter base resource.

In yet another possible implementation manner, for the basic resource including the CP, in the Z consecutive basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of the u-th basic resource and a phase of a reference signal carried on a first subcarrier of the v-th basic resource is

Exemplarily, taking basic resources including a CP as an example, if the CP lengths of the 2 nd to the Z th basic resources in the Z consecutive basic resources are equal and are all L, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the first subcarrier of the 1 st basic resource is L

I.e. 2 pi (u-1) Lk/N, k being the index of the first subcarrier and N being the symbol length of the third OFDM symbol.

For example, taking an example that one basic resource includes 2 third OFDM symbols, and each third OFDM symbol occupies 8 subcarriers, referring to fig. 14, RSs carried on 8 subcarriers of the third OFDM symbol of the 1 st basic resource are S (0), S (1), S (2), …, and S (7), respectively. By the scheme provided by the embodiment of the present application, the RSs carried on the 8 subcarriers of the third OFDM symbol of the 2 basic resources are S (0) × exp (i × 0 × 2 pi L/N), S (1) × exp (i × 1 × 2 pi L/N), S (2) × exp (i × 2 pi L/N), …, S (7) × (i × 7 × 2 pi L/N), and the RSs carried on the 8 subcarriers of the OFDM symbol of the 3 basic resources are S (0) × exp (i × 2 × 0 pi L/N), S (1) × 2 pi L/N), S (2) × 2 pi L/N, S (i × 2 pi L/N), and S (7) × 2 pi L/N). Wherein exp (x) represents e^x。

Next, the structure of the second basic resource is taken as an example, that is, the basic resource includes a CS.

For a basic resource containing CS, the phase difference between the phase of the reference signal carried on the first subcarrier of the first basic resource and the phase of the reference signal carried on the first subcarrier of the second basic resource is also determined by the symbol length of the third OFDM symbol and/or the CS length of the basic resource.

For the basic resource containing CS, in any two adjacent basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource is 2 pi Lk/N, where N is a symbol length of the third OFDM symbol, L is a CS length of the basic resource, and k is an index of the first subcarrier. Illustratively, L is the CS length of the previous base resource.

For the basic resource containing CS, in the Z continuous basic resources, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the first subcarrier of the v-th basic resource is

Wherein N is a symbol length of the third OFDM symbol, Ln is a CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

Secondly, take the structure of the third basic resource as an example, that is, the basic resource includes CS and CP.

For the basic resource containing the CP and the CS, a phase difference between a phase of the reference signal carried on the first subcarrier of the first basic resource and a phase of the reference signal carried on the first subcarrier of the second basic resource is further determined by a symbol length of the third OFDM symbol and/or a CP length of the basic resource and a CS length. For the basic resources including CP and CS, in any two adjacent basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource is 2 pi (L + J) k/N, where N is a symbol length of the third OFDM symbol, L is a CP length of the basic resource, J is a CS length of the basic resource, and k is an index of the first subcarrier. Illustratively, L is the CP length of the next basic resource, and J is the CS length of the previous basic resource.

For the basic resources including the CP and the CS, in the Z consecutive basic resources, a phase difference between a phase of a reference signal carried on a first subcarrier of the u-th basic resource and a phase of a reference signal carried on a first subcarrier of the v-th basic resource is

Exemplarily, taking basic resources including CP and CS as an example, in the Z consecutive basic resources, the CP lengths of the 2 nd to Z th basic resources are equal and are all L, the CS lengths of the 1 st to Z-1 th basic resources are equal and are all J, and then the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the first subcarrier of the 1 st basic resource is J

I.e., 2 pi (u-1) (L + J) k/N, k being the index of the first subcarrier and N being the length of the third OFDM symbol excluding the CP or CS.

It should be noted that, the above is based on the previous basic resource, and the RS of the next basic resource is point-by-point multiplied by one in the frequency domain

Linear phase of the base resource, but also can be based on the next base resource, and the RS of the previous base resource is point-by-point multiplied by one on the frequency domain

The two are substantially the same, that is, the phase difference between the RSs on the k-index subcarrier in the two adjacent basic resources is

It should be understood that, since the length of the third OFDM symbol is the same as the length of the fourth OFDM symbol except for the CP of the fourth OFDM symbol, in the above, the phase difference of the reference signal on the first subcarrier of different basic resources may be determined not only according to the length of the third OFDM symbol but also according to the length of the fourth OFDM symbol. For example, if the third OFDM symbol is N, the fourth OFDM symbol is Ncp, and the CP length of the fourth OFDM symbol is Lcp, then N is Ncp-Lcp.

The principle that the cyclic shift of the basic resource in the time domain appears as a linear phase offset of the corresponding frequency domain signal in the frequency domain (i.e. the linear relationship between the phase difference and the index k of the subcarrier) is described above and is not described herein again.

For a base station sending a reference signal, linear phase compensation can be performed on the reference signal loaded on different basic resources on a frequency domain, so that an effect equivalent to time domain cyclic shift is achieved; the base station transmitting the reference signal transmits the reference signal so that the base station receiving the reference signal can detect the reference signal in a frequency domain correlation manner. The sending base station may generate the reference signal carried on one basic resource first, and then generate the reference signal carried on another basic resource according to the relationship, in the time domain/frequency domain, of the reference signal between different basic resources in the embodiment of the present application, or the sending base station may directly generate the reference signal carried on multiple basic resources according to the relationship, in the time domain/frequency domain, of the reference signal between different basic resources in the embodiment of the present application, or generate the reference signal in another manner, which is not limited in the present application.

In addition, in the embodiment of the present application, the RS for measurement between base stations may not occupy all subcarriers of one OFDM symbol in the frequency domain. For example, the total number of subcarriers of one OFDM symbol is N, the RS may occupy only M subcarriers, and M ≦ N. But the phase difference of two OFDM symbols on the same subcarrier is related to the length N of one OFDM symbol. In general, the number of time domain samples of an OFDM symbol is the same as the total number of subcarriers, and therefore the phase difference can also be considered to be related to the total number of subcarriers N of one OFDM symbol.

Usually, the frequency domain resources occupied by the RS on the two OFDM symbols before and after or the two RSs on the two basic resources before and after are the same frequency domain resources, that is, are carried on the same subcarrier. If the number of subcarriers carrying the reference signal is smaller than the number of subcarriers carrying the OFDM symbol, other signals, such as data signals between the base station and the user equipment, may be carried on other subcarriers. If other signals carried in different OFDM symbols are different, the time domain signals superimposed on the time domain by all subcarriers of the OFDM symbols may not satisfy the cyclic characteristic, but the time domain signals superimposed on the time domain by only the subcarriers carrying the reference signals still satisfy the cyclic characteristic, so the reference signals can still be detected in a blind detection manner.

The embodiment of the application is also suitable for the situation that the frequency domain resources occupied by the RS on the front OFDM symbol and the rear OFDM symbol or the RS on the front basic resource and the rear basic resource are different. For example, referring to fig. 8, the 1 st OFDM symbol occupies the 1 st subcarrier to the 4 th carrier, and the 2 nd OFDM symbol occupies the 5 th subcarrier to the 8 th subcarrier. For another example, referring to fig. 8, the 1 st OFDM symbol occupies the 1 st subcarrier to the 6 th carrier, and the 2 nd OFDM symbol occupies the 3 rd subcarrier to the 8 th subcarrier.

The specific sequence of the measurement RS is not limited in the embodiments of the present application. For example, the RS may be a pseudo-random sequence based on Gold sequence and QPSK modulation, or based on Zadoff-Chu (Z)C) A low peak to average power ratio (PAPR) sequence of the sequence. In particular, if the RS is a ZC sequence or a low peak-to-average ratio sequence based on a ZC sequence, the RS is point-by-point linear phase due to the characteristics of the sequence

Which is also equivalent to the L-point cyclic shift of the RS. For example, if an RS signal is carried on each OFDM symbol of M consecutive OFDM symbols, CP lengths of 2 nd to M th OFDM symbols are all L, and RS carried on k-th subcarrier of 1 st OFDM symbol is S (k), RS carried on subcarrier k of M-th OFDM symbol is S (k + (M-1) × L), that is, S (k + (M-1) × L) and S (k + (M-1) × L)

Are equal.

If base station 1 transmits on the downlink symbols when base station 1 is far from base station 2, base station 2 may need to receive on the guard interval and/or on the uplink OFDM symbols due to the delay.

See fig. 15 for an illustration:

s901, the base station 1 transmits a reference signal to the base station 2 on a second resource. Wherein the second resource is a downlink transmission resource.

The first mode is as follows: the second resource includes M consecutive downlink OFDM symbols. The M consecutive downlink OFDM symbols satisfy the above-mentioned relationship in the time domain and/or the frequency domain, and are not described herein again.

In a second way, the second resource comprises Z consecutive basic resources; the Z consecutive basic resources satisfy the relationship described above in the time domain and/or the frequency domain, and are not described herein again. The OFDM symbols included in the basic resource are downlink OFDM symbols.

S902, the base station 2 determines a first resource for receiving a reference signal, where the first resource includes an uplink OFDM symbol and/or a guard interval.

S903, the base station 2 receives the reference signal on the first resource.

Optionally, for the first manner, before S901, the base station 1 generates a sequence corresponding to the reference signal.

The sequence corresponding to the reference signal may be a sequence mapped onto one OFDM symbol or basic resource, and based on the relationship in the time domain and/or the frequency domain between different OFDM symbols or between different basic resources described in this embodiment of the application, a sequence on another OFDM symbol or a sequence on another basic resource may be generated.

The sequences mapped to the M OFDM symbols or the Z basic resources may also be directly generated according to the relationship between different OFDM symbols or basic resources in the time domain and/or the frequency domain in the embodiment of the present application.

For the second resource described in the first mode, the base station 1 transmits the reference signal to the base station 2 on the second resource, and includes:

the base station 1 maps a sequence corresponding to a reference channel to Resource Elements (REs) (k, l) of M consecutive OFDM symbols. k denotes a subcarrier index and l denotes an OFDM symbol index.

Exemplarily, the reference signal sequence a (k, l) carried on RE (k, l) satisfies the condition shown in formula (12):

wherein j is

l_startFor the index of the l-th OFDM symbol among the M OFDM symbols carrying the RS,

indicates the length of the CP corresponding to the ith OFDM symbol,

which represents the bandwidth of the system, i.e., the total number of subcarriers in one OFDM symbol. k has a certain correspondence with k ', e.g. k' ═ m × k + k_offsetWherein m and k_offsetIs a predefined or configurable value. Examples of the inventionSexual, m ═ 1, k_offsetWhen k 'is equal to 0, k' is equal to k.

For the second resource described in the second manner, the base station 1 transmits the reference signal to the base station 2 on the second resource, including:

the base station 1 maps the sequence corresponding to the reference channel to the resource elements (k, l') of each third OFDM symbol in Z consecutive basic resources. k denotes a subcarrier index and l' denotes a basic resource index.

Exemplarily, the reference signal sequence a (k, l ') carried on RE (k, l') satisfies the condition shown in formula (13):

wherein j is

l′_startFor the index of the l' th basic resource among the Z bases carrying the RS,

indicates the length of the CP corresponding to the ith' basic resource,

which represents the bandwidth of the system, i.e. the total number of subcarriers in one OFDM symbol. k has a certain correspondence with k ', e.g. k' ═ m × k + k_offsetWherein m and k_offsetA predefined or configurable value. Exemplarily, m is 1, k_offsetWhen k 'is equal to 0, k' is equal to k.

In a possible embodiment, the same transceiver-time configuration may be used between the

base stations

1 and 2 participating in the measurement. The transceiving time configuration information includes at least one of: uplink and downlink switching period, latest downlink sending time and earliest uplink receiving time. The base station 2 may determine the transceiving time configuration according to the transceiving time configuration information, and determine the start time of the blind detection RS.

The time domain positions for sending the reference signals between the base stations can also adopt the same time domain position, so that when the base station 2 receives and blindly detects an RS, the interference range can be determined according to the fixed time domain position, the range of resources needing interference elimination can be determined, the distance between an interference source (the base station 1) and the base station can be more conveniently calculated, and the positioning of the interference source base station is facilitated. As shown in fig. 16.

In this embodiment of the present application, the M OFDM symbols carrying the RS may occupy the last M symbols of the downlink transmission time, or the Z basic resources carrying the RS may occupy the last Z basic resources of the downlink transmission time. Taking the last M symbols of the downlink transmission time occupied by the M RS-bearing OFDM symbols as an example, on one hand, the maximum interference range can be determined, because the RS is the last M symbols of the downlink transmission, after the base station 2 detects the RS, it can be determined that the range after the time domain position where the RS is located is not interfered by the base station 1 in the different direction, so that interference cancellation means can be further applied, for example, lower-order modulation, lower code rate, and the like are applied to the region interfered by the CLI; on the other hand, the success rate of detection can be guaranteed to the maximum extent, as shown in fig. 17, if the RS is not in the last M symbols of the DL portion, there is a possibility that the RS is still in the DL region after the delay, and the interfered station cannot detect the RS, in this case, the DL portion of the interfering base station 1 still generates the anisotropic interference to the UL portion of the interfered base station 2.

Based on this, optionally, in S901, before the base station 1 transmits the reference signal to the base station 2 on the second resource, the method further includes:

s904, the base station 1 and/or the base station 2 receives the transceiving time configuration information.

The transmit-receive time configuration information may be notified to the receiving base station 2 by the base station 1, or may be notified to the receiving base station 1 by the base station 2; or, the transceiver-transmitter time configuration information may be configured to the base station 1 and/or the base station 2 by a higher-level control node, or configured in the base station 1 and/or the base station 2 when an engineer performs network deployment. When the base station 2 receives the reference signal on the first resource, the base station 2 may locally generate an RS1, perform frequency domain cross-correlation operation with the received reference signal using a local RS1, perform inverse fourier transform on the result of the frequency domain cross-correlation, and transform the result to a time domain to obtain a correlation peak; when the correlation peak exceeds a certain threshold, the base station 2 may determine that the reference signal RS1 transmitted from the base station 1 is received.

As an example, referring to fig. 18, base station 1 sends a downlink OFDM symbol used by RS1, and base station 1 detects a reference signal on uplink OFDM due to a time delay caused by the long distance between base station 1 and base station 2.

In addition, the execution time of step S903 in the above steps may be earlier than step S901, and since the base station 1 is far away from the base station 2 and the troposphere affects the propagation of the signal to the warp effect, the base station 2 does not determine when the reference signal from the base station 1 arrives, so the base station 2 may detect whether there is RS1 on all the symbols that may receive the reference signal, and step S903 may be executed earlier than step S901. However, although the bs 2 can start the detection as early as possible, the bs 2 can detect the RS1 transmitted by the bs 1 only after the RS1 of the bs 1 reaches the bs 2.

The design method of the reference signals between the base stations at a longer distance provided by the embodiment of the application can also be applied to a measurement scene between adjacent base stations (base stations at a shorter distance). In the measurement scenario of the neighboring base station, the time delay due to the geographical distance is negligible. For example, base station 1 and base station 3 are two adjacent base stations, and the time when base station 1 transmits the reference signal can be regarded as the time when base station 3 receives the reference signal.

See fig. 19 for a view:

s1301, the base station 1 transmits a reference signal on the second resource. Wherein the second resource is a downlink transmission resource.

The second resource includes M consecutive downlink OFDM symbols, or the second resource includes a guard time interval (GP). Still alternatively, the second resource includes Z consecutive basic resources. The OFDM symbols included in the basic resource are downlink OFDM symbols.

For example, the reference signals carried by M consecutive OFDM symbols or Z consecutive basic resources satisfy the relationship in the time domain and/or the frequency domain, and are not described herein again.

S1302, the base station 3 determines a first resource for receiving the reference signal according to the obtained first information. Wherein the first information includes time-frequency resource location information for carrying the reference signal. That is, the first information includes the time domain resource and/or the frequency domain resource location of the second resource.

The first information may be notified to the receiving base station 3 by the base station 1, or may be configured to the base station 3 by a higher-level control node, or configured in the base station 3 when an engineer performs network deployment.

S1303, the base station 3 receives the reference signal on the first resource.

In a possible implementation, the base station 3 may further obtain second information, where the second information includes the reference signal or parameter information required for generating the reference signal; thereby determining that the reference signal is received on the first resource based on the second information or performing channel estimation based on the second information and the received reference signal.

The first information and the second information may be included in the same configuration information and sent to the base station 3 by the base station 1, or may be configured to the base station 3 by a higher-level control node, or configured in the base station 3 by an engineer during network deployment. The first information and the second information may be included in different configuration information and transmitted to the base station 3 by the base station 1 through the same message or different messages, or may be configured to the base station 3 by a higher-level control node through the same message or different messages.

For example, the parameter information required for generating the reference signal may be an initial phase of a Gold sequence, a root sequence of a ZC sequence, or the like. The base station 3 may receive the reference signal (as a local reference signal) or locally generate the same reference signal as the reference signal transmitted by the base station 1 (the generated reference signal is used as a local reference signal). On the one hand, whether the sending base station sends the RS can be detected through the cross correlation between the local reference signal and the received signal. On the other hand, the base station 3 can perform channel estimation by using a local reference signal and a received signal (including the RS transmitted by the base station 1).

For example, referring to fig. 20A, the base station 1 transmits a reference signal in the GP, and the base station 3 receives a reference signal in the GP.

In fig. 20A, DL symbols and UL symbols are for terminal devices, which do not normally transceive in the GP; therefore, when the base stations perform measurement, the RS can be transmitted and received within the GP range, and at this time, the RS does not interfere with data transmitted by the terminal device and data that needs to be received by the UE.

For another example, referring to fig. 20B, the base station 1 transmits the reference signal in the downlink OFDM symbols occupying M, and the base station 3 receives the reference signal in the GP. Thus, it can be ensured that the RS transmitted from the base station 1 does not interfere with the uplink part of the base station 3.

In the embodiment of the present application, the same RS may be multiplexed for the super-long-range interference measurement and the interference measurement of the neighboring base station, as shown in fig. 20C. The base station 1 sends the same RS to the

base stations

2 and 3, and the RS is used for ultra-long distance measurement and measurement between adjacent base stations; for the base station 3, since it is a neighbor station, it can be determined that the receiving time is determined according to the transmitting time of the base station 1, and it is not necessary to perform "blind" detection in all GP and/or UL regions; for the measurement between the base station 1 and the base station 3, it is necessary to perform "blind" detection in the UL region, which is specifically referred to the above description that the reference signal carried between the OFDM symbols satisfies the relationship in the time domain and/or the frequency domain, and is not described herein again.

The communication device according to the embodiment of the present application will be described in detail below with reference to fig. 21A, 21B, and 22.

Based on the same inventive concept as the method embodiment described above, referring to fig. 21A, a schematic structural diagram of an apparatus provided in the embodiment of the present application may include a transceiver 1510 and a processing unit 1520.

In a possible embodiment, the apparatus may be applied to a base station of a transmitting side, and the transceiving unit 1510 may be configured to transmit a reference signal to a base station of a receiving side, or receive transceiving time configuration information transmitted by a higher layer control node, and the like. Illustratively, the transceiving unit 1510 performs step S901, or S1301. The processing unit 1520 may be configured to generate a reference signal, and the like, and the specific processing unit 1510 may be configured to implement the functions performed by the base station 1 in the embodiment corresponding to fig. 15 or fig. 19.

In a possible embodiment, the apparatus may be configured to receive a reference signal transmitted by the base station of the receiving side, or receive the transceiving time configuration information transmitted by the higher-level control node, or receive the first information, the second information, and so on. Illustratively, the transceiving unit 1510 may be configured to perform step S903, or step 1303. The processing unit 1520, which may be configured to determine resources for receiving a reference signal, or determine an interfering base station according to the received reference signal, or perform channel estimation, etc., is exemplary, and the processing unit 1520, which is configured to perform step S902 or step S1302. The specific processing unit 1510 may be configured to implement the functions performed by the base station 2 in the embodiments corresponding to fig. 15 or fig. 19.

Fig. 21B is a schematic structural diagram of a network device according to an embodiment of the present application, for example, a schematic structural diagram of a base station. As shown in fig. 21B, the base station may be applied to the system shown in fig. 1, and performs the functions of the network device (or the base station) in the above method embodiment. The base station 150 may include one or more radio frequency units, such as a Remote Radio Unit (RRU) 1501 and one or more baseband units (BBUs) (which may also be referred to as digital units, DUs) 1502. The RRU 1501, which may be referred to as a transceiver unit, transceiver circuit, or transceiver, etc., may include at least one antenna 15011 and a radio frequency unit 15012. The RRU 1501 is mainly used for transceiving radio frequency signals and converting the radio frequency signals and baseband signals, for example, for sending the reference signals described in the above embodiments to a terminal device. The BBU 1502 is mainly used for performing baseband processing, controlling a base station, and the like. The RRU 1501 and the BBU 1502 may be physically disposed together or may be physically disposed separately, that is, a distributed base station.

The BBU 1502 is a control center of a base station, and may also be referred to as a processing unit, and is mainly used for performing baseband processing functions, such as channel coding, multiplexing, modulation, spreading, and the like. For example, the BBU (processing unit) 1502 can be used to control the base station to execute the operation flow related to the network device (or base station) in the above method embodiment.

In an example, the BBU 1502 may be formed by one or more boards, and the boards may jointly support a radio access network (e.g., an LTE network or a 5G network) with a single access indication, or may respectively support radio access networks of different access systems (e.g., an LTE network, a 5G network or other networks). The BBU 1502 further includes a memory 15021 and a processor 15022, the memory 15021 being used to store the necessary instructions and data. The processor 15022 is configured to control the base station to perform necessary actions, for example, to control the base station to perform the operation flow of the above method embodiment with respect to the network device (or the base station). The memory 15021 and processor 15022 may serve one or more boards. That is, the memory and processor may be provided separately on each board. Multiple boards may share the same memory and processor. In addition, each single board can be provided with necessary circuits.

Fig. 22 shows a schematic diagram of a communication device 1600. The apparatus 1600 may be used to implement the methods described in the above method embodiments, which may be referred to as descriptions in the above method embodiments. The communication device 1600 may be a chip, a network device (e.g., a base station), etc.

The communication device 1600 includes one or more processors 1601. The processor 1601 may be a general purpose processor or a special purpose processor, etc. For example, a baseband processor, or a central processor. The baseband processor may be used to process communication protocols and communication data, and the central processor may be used to control a communication device (e.g., a base station, a terminal, or a chip), execute a software program, and process data of the software program. The communication device may include a transceiving unit to enable input (reception) and output (transmission) of signals. For example, the communication device may be a chip, and the transceiving unit may be an input and/or output circuit of the chip, or a communication interface. The chip can be used for a terminal or a base station or other network equipment. As another example, the communication device may be a base station or a network device, and the transceiver unit may be a transceiver, a radio frequency chip, or the like.

The communication device 1600 comprises one or more processors 1601, wherein the one or more processors 1601 are capable of implementing the method performed by the base station (base station 1, base station 2, or base station 3) in the embodiment shown in fig. 15 or fig. 19.

In one possible design, the communications apparatus 1600 includes means (means) for generating a reference signal, and means (means) for transmitting the reference signal. The functions of generating the means for the reference signal and transmitting the means for the reference signal may be implemented by one or more processors. The reference signal may be generated, for example, by one or more processors, and transmitted through a transceiver, or an interface of an input/output circuit, or chip. The reference signal can be found in the related description of the above method embodiments.

In one possible design, the communications apparatus 1600 includes means (means) for receiving reference signals. The reference signal may be received, for example, by a transceiver, or an input/output circuit, or an interface of a chip.

Optionally, the processor 1601 may also implement other functions than the method of the embodiment shown in fig. 15 or fig. 19.

Alternatively, in one design, the processor 1601 may execute instructions that cause the communication device 1600 to perform the methods described in the method embodiments above. The instructions may be stored in whole or in part within the processor, such as instructions 1603, or may be stored in whole or in part in a memory 1602 coupled to the processor, such as instructions 1604, or may collectively cause the communication apparatus 1600 to perform the method described in the above method embodiments by

instructions

1603 and 1604.

In yet another possible design, the communication apparatus 1600 may also include a circuit, which may implement the functions of the network device (or the base station) in the foregoing method embodiments.

In yet another possible design, the communication device 1600 may include one or more memories 1602 having stored thereon instructions 1604 that are executable on the processor to cause the communication device 1600 to perform the methods described in the above method embodiments. Optionally, the memory may further store data therein. Instructions and/or data may also be stored in the optional processor. For example, the one or more memories 1602 may store the corresponding relations described in the above embodiments, or the related parameters or tables referred to in the above embodiments. The processor and the memory may be provided separately or integrated together.

In yet another possible design, the communication device 1600 may further include a transceiver 1605 and an antenna 1606. The processor 1601 may be referred to as a processing unit and controls a communication device (a terminal or a base station). The transceiving unit 1605 may be referred to as a transceiver, transceiving circuit, transceiver, or the like, for implementing transceiving function of the communication device through the antenna 1606.

The present application also provides a communication system comprising a plurality of network devices (or base stations) as described above. One or more terminal devices may also be included.

It should be noted that the processor in the embodiments of the present application may be an integrated circuit chip having signal processing capability. In implementation, the steps of the above method embodiments may be performed by instructions in the form of integrated logic circuits of hardware or software in a processor. The processor may be a general purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA) or other programmable logic device, discrete gate or transistor logic device, or discrete hardware components. The methods, steps and logic blocks disclosed in the embodiments of the present application may be implemented or performed. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in ram, flash memory, rom, prom, or eprom, registers, etc. storage media as is well known in the art. The storage medium is located in a memory, and a processor reads information in the memory and completes the steps of the method in combination with hardware of the processor.

It will be appreciated that the memory in the embodiments of the subject application can be either volatile memory or nonvolatile memory, or can include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), Synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchlink DRAM (SLDRAM), and direct bus RAM (DR RAM). It should be noted that the memory of the systems and methods described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

The present application further provides a computer-readable medium, on which a computer program is stored, where the computer program is executed by a computer to implement the communication method in any of the above method embodiments.

The embodiment of the present application further provides a computer program product, and when executed by a computer, the computer program product implements the communication method described in any of the above method embodiments.

In the above embodiments, the implementation may be wholly or partially realized by software, hardware, firmware, or any combination thereof. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions may be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disk (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

The embodiment of the application also provides a processing device, which comprises a processor and an interface; the processor is configured to execute the communication method in any of the above method embodiments.

It should be understood that the processing device may be a chip, the processor may be implemented by hardware or software, and when implemented by hardware, the processor may be a logic circuit, an integrated circuit, or the like; when implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory, which may be integrated in the processor, located external to the processor, or stand-alone.

It should be appreciated that reference throughout this specification to "one embodiment" or "an embodiment" means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present application. Thus, the appearances of the phrases "in one embodiment" or "in an embodiment" in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. It should be understood that, in the various embodiments of the present application, the sequence numbers of the above-mentioned processes do not mean the execution sequence, and the execution sequence of each process should be determined by its function and its inherent logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

Additionally, the terms "system" and "network" are often used interchangeably herein. The term "and/or" herein is merely an association describing an associated object, meaning that three relationships may exist, e.g., a and/or B, may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" in this document generally indicates that the preceding and following associated objects are in an "or" relationship.

It should be understood that in the embodiment of the present application, "B corresponding to a" means that B is associated with a, from which B can be determined. It should also be understood that determining B from a does not mean determining B from a alone, but may be determined from a and/or other information.

Those of ordinary skill in the art will appreciate that the elements and algorithm steps of the examples described in connection with the embodiments disclosed herein may be embodied in electronic hardware, computer software, or combinations of both, and that the components and steps of the examples have been described in a functional general in the foregoing description for the purpose of illustrating clearly the interchangeability of hardware and software. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It is clear to those skilled in the art that, for convenience and brevity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, a division of a unit is merely a logical division, and an actual implementation may have another division, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may also be an electric, mechanical or other form of connection.

Units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiments of the present application.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit. The integrated unit can be realized in a form of hardware, and can also be realized in a form of a software functional unit.

Through the above description of the embodiments, it is clear to those skilled in the art that the present application can be implemented by hardware, firmware, or a combination thereof. When implemented in software, the functions described above may be stored on or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media includes both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage media may be any available media that can be accessed by a computer. Taking this as an example but not limiting: computer-readable media can include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Furthermore, the method is simple. Any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL), or wireless technologies such as infrared, radio, and microwave, the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the fixation of the belonging medium. Disk and disc, as used herein, includes Compact Disc (CD), laser disc, optical disc, Digital Versatile Disc (DVD), floppy Disk and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of protection of computer-readable media.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present application without departing from the scope of the application. Thus, if such modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is intended to include such modifications and variations as well.

Claims

1. A method for transmitting a reference signal, comprising:

transmitting reference signals carried on M consecutive OFDM symbols;

2. The method of claim 1, further comprising:

3. The method of claim 1, wherein:

the phase difference between the phase of the reference signal carried on the first subcarrier of the first OFDM symbol and the phase of the reference signal carried on the first subcarrier of the second OFDM symbol is also determined by the symbol length of the OFDM symbol and/or the cyclic prefix CP length of the OFDM symbol.

4. The method of claim 3, wherein:

the first OFDM symbol is separated from the second OFDM symbol by X OFDM symbols, the first OFDM symbol is earlier than the second OFDM symbol in a time domain, and X is an integer greater than or equal to 0; the CP length of the OFDM symbol is determined by the CP lengths of the X OFDM symbols and the CP length of a second OFDM symbol.

5. The method of any one of claims 1-4, wherein:

in any two adjacent OFDM symbols of the M consecutive OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a next OFDM symbol and a phase of a reference signal carried on a first subcarrier of a previous OFDM symbol is 2 pi Lk/N, where N is a symbol length of the OFDM symbol, L is a CP length of the OFDM symbol, and k is an index of the first subcarrier.

6. The method of any one of claims 1-4, wherein:

in the M continuous OFDM symbols, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th OFDM symbol and the phase of the reference signal carried on the first subcarrier of the v-th OFDM symbol is

Wherein N is a symbol length of the OFDM symbol, Ln is a CP length of an nth OFDM symbol, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

7. The method of any of claims 1-4, wherein the M consecutive OFDM symbols are the last M OFDM symbols of a downlink transmission portion of an uplink and downlink switching period.

8. A method for receiving a reference signal, comprising:

receiving a reference signal on the first resource; the reference signal is sent through a second resource, where the second resource includes M consecutive downlink OFDM symbols; in the M consecutive downlink OFDM symbols, a phase difference between a phase of a reference signal carried on a first subcarrier of a first OFDM symbol and a phase of a reference signal carried on a first subcarrier of a second OFDM symbol is determined by an index of the first subcarrier, where the first OFDM symbol and the second OFDM symbol are any two OFDM symbols of the M consecutive downlink OFDM symbols, and M is an integer greater than or equal to 2.

9. The method of claim 8, further comprising:

10. The method of claim 8, wherein:

11. The method of claim 10, wherein:

12. The method of any one of claims 8-11, wherein:

13. The method of any one of claims 8-11, wherein:

14. The method according to any of claims 8-11, wherein the M consecutive OFDM symbols are the last M OFDM symbols of the downlink transmission part of the uplink and downlink switching period.

15. A method for transmitting a reference signal, comprising:

transmitting reference signals carried on M consecutive OFDM symbols;

in the M consecutive OFDM symbols, any two adjacent OFDM symbols are, in the time domain, the same signal obtained by performing cyclic shift on the reference signal carried by the portion of the latter OFDM symbol excluding the CP as the reference signal carried by the portion of the former OFDM symbol excluding the CP, and the length of the cyclic shift is determined by the length of the cyclic prefix CP of the OFDM symbol.

16. The method of claim 15, wherein:

the CP length of the OFDM symbol is the CP length of the next OFDM symbol in the two adjacent OFDM symbols.

17. The method according to claim 15 or 16, wherein, in M consecutive OFDM symbols, the reference signal carried by the part of the u-th OFDM symbol excluding the CP is the same as the signal obtained by performing (u-v) · L-long cyclic shift on the reference signal carried by the part of the v-th OFDM symbol excluding the CP, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and L is the CP length of the OFDM symbol.

18. The method of claim 15, wherein the reference signal carried by the portion of the u-th OFDM symbol excluding the CP is performed with the reference signal carried by the portion of the v-th OFDM symbol excluding the CP in the M consecutive OFDM symbols

The signals obtained by long cyclic shift are the same, Ln is the CP length of the nth OFDM symbol, and u is more than 1 and less than or equal to MV is an integer greater than or equal to 1 and less than u.

19. The method of claim 15 or 16, wherein the M consecutive OFDM symbols are the last M OFDM symbols of a downlink transmission part of an uplink and downlink switching period.

20. A method for receiving a reference signal, comprising:

receiving a reference signal on the first resource; the reference signal is sent through a second resource, where the second resource includes M consecutive downlink OFDM symbols; in the M consecutive OFDM symbols, any two adjacent OFDM symbols are, in the time domain, the same signal obtained by performing cyclic shift on the reference signal carried by the portion of the latter OFDM symbol excluding the CP as the reference signal carried by the portion of the former OFDM symbol excluding the CP, and the length of the cyclic shift is determined by the length of the cyclic prefix CP of the OFDM symbol.

21. The method of claim 20, wherein:

22. The method according to claim 20 or 21, wherein, in M consecutive OFDM symbols, the reference signal carried by the part of the u-th OFDM symbol excluding the CP is the same as the signal obtained by performing (u-v) · L-long cyclic shift on the reference signal carried by the part of the v-th OFDM symbol excluding the CP, u is an integer greater than 1 and less than or equal to M, v is an integer greater than or equal to 1 and less than u, and L is the CP length of the OFDM symbol.

23. The method of claim 20, wherein the u-th OFDM symbol is removed from the M consecutive OFDM symbolsThe reference signal carried by the part of the CP is carried out with the reference signal carried by the part of the v-th OFDM symbol except the CP

24. The method of claim 20 or 21, wherein the M consecutive OFDM symbols are the last M OFDM symbols of a downlink transmission part of an uplink and downlink switching period.

25. A method for transmitting a reference signal, comprising:

transmitting reference signals carried on Z consecutive basic resources;

the basic resource comprises Y continuous third orthogonal frequency division multiplexing OFDM symbols, and a cyclic prefix CP and/or a cyclic suffix CS; reference signals carried on Y third OFDM symbols included in one basic resource are the same; the third OFDM symbol does not include a CP;

26. The method of claim 25, further comprising:

27. The method of claim 25, wherein when the basic resources include only Y consecutive third OFDM symbols and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is further determined by a symbol length of the third OFDM symbol and/or a CP length of the basic resources.

28. The method of claim 27, wherein:

the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CP length of the basic resource is determined by the CP lengths of the X basic resources and the CP length of a second basic resource.

29. The method according to any of claims 25-28, wherein when the basic resources only include Y consecutive third OFDM symbols and one cyclic prefix CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a following basic resource and a phase of a reference signal carried on a first subcarrier of a preceding basic resource of any two adjacent basic resources among the Z consecutive basic resources is 2 pi Lk/N, where N is a symbol length of the third OFDM symbol, L is a CP length of a basic resource, and k is an index of the first subcarrier.

30. The method according to any of claims 25-28, wherein when the basic resource comprises only Y consecutive third OFDM symbols and one cyclic prefix CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th basic resource and a phase of a reference signal carried on a first subcarrier of a v-th basic resource among the Z consecutive basic resources is

31. The method of claim 25, wherein when the basic resources include only Y consecutive third OFDM symbols, and one CS, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is further determined by a symbol length of the third OFDM symbol and/or a CS length of the basic resources.

32. The method of claim 31, wherein:

the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CS length of the basic resource is determined by the CS lengths of the X basic resources and the CS length of the first basic resource.

33. The method according to any of claims 25-26, 31, wherein when the basic resources only comprise Y consecutive third OFDM symbols and one CS, a phase difference between a phase of a reference signal carried on a first subcarrier of a following basic resource and a phase of a reference signal carried on a first subcarrier of a preceding basic resource of any two adjacent basic resources among the Z consecutive basic resources is 2 pi Jk/N, where N is a symbol length of the third OFDM symbol, J is a CS length of a basic resource, and k is an index of the first subcarrier.

34. The method according to any of claims 25-26, 31, wherein when the basic resource comprises only Y consecutive third OFDM symbols and one CS, the phase difference between the phase of the reference signal carried on the first subcarrier of the u-th basic resource and the phase of the reference signal carried on the first subcarrier of the v-th basic resource in the Z consecutive basic resources is

35. The method of claim 25, wherein when the basic resources include Y consecutive third OFDM symbols, one CS, and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a first basic resource and a phase of a reference signal carried on a first subcarrier of a second basic resource is further determined by a symbol length of the third OFDM symbol, a CS length of the basic resource, and a CP length of the basic resource.

36. The method of claim 35, wherein:

the first basic resource is separated from the second basic resource by X basic resources, the first basic resource is earlier than the second basic resource in the time domain, and X is an integer greater than or equal to 0; the CS length of the basic resource is determined by the CS lengths of the X basic resources and the CS length of the first basic resource, and the CP length of the basic resource is determined by the CP lengths of the X basic resources and the CP length of the second basic resource.

37. The method according to any of claims 25-26, 35, wherein when the basic resources comprise Y consecutive third OFDM symbols, one CS and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a subsequent basic resource and a phase of a reference signal carried on a first subcarrier of a previous basic resource is 2 pi (L + J) k/N for any two adjacent basic resources among the Z consecutive basic resources, where N is a symbol length of the third OFDM symbol, L is a CP length of a basic resource, J is a CS length of a basic resource, and k is an index of the first subcarrier.

38. The method according to any of claims 25-26, 35, wherein when the basic resources comprise Y consecutive third OFDM symbols, one CS and one CP, a phase difference between a phase of a reference signal carried on a first subcarrier of a u-th basic resource and a phase of a reference signal carried on a first subcarrier of a v-th basic resource among the Z consecutive basic resources is

Wherein N is a symbol length of the third OFDM symbol, Ln is a CP length of an nth basic resource, Jn is a CS length of the nth basic resource, u is an integer greater than 1 and less than or equal to Z, v is an integer greater than or equal to 1 and less than u, and k is an index of the first subcarrier.

39. The method according to any of claims 25-28, wherein said Z consecutive basic resources are the last Z basic resources of the downlink transmission part of the uplink and downlink switching period.

40. A communication apparatus configured to perform the method of any of claims 1-39.

41. A communications apparatus, comprising: a processor coupled with a memory;

a memory for storing a computer program;

a processor for executing a computer program stored in the memory to cause the apparatus to perform the method of any of claims 1-39.

42. A readable storage medium comprising a program or instructions for performing the method of any one of claims 1-39 when the program or instructions are run on a computer.