CN108282432B

CN108282432B - Synchronous signal transmission method, synchronous signal detection method, base station and user equipment

Info

Publication number: CN108282432B
Application number: CN201710011352.0A
Authority: CN
Inventors: 曲秉玉; 刘建琴
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2017-01-06
Filing date: 2017-01-06
Publication date: 2020-06-02
Anticipated expiration: 2037-01-06
Also published as: WO2018127085A1; CN108282432A

Abstract

The embodiment of the invention discloses a synchronous signal transmission method, a synchronous signal detection method, a base station and user equipment. The base station acquires a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N); the base station generates a synchronization signal sequence with the length of M according to the first root sequence index; and the base station maps the synchronization signal sequence with the length of M on the M subcarriers and transmits the synchronization signal sequence.

Description

Synchronous signal transmission method, synchronous signal detection method, base station and user equipment

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a synchronization signal transmission method, a synchronization signal detection method, a base station, and a user equipment.

Background

In a communication system, a base station performs downlink time and frequency coarse Synchronization through a Synchronization Signal during downlink transmission, where the Synchronization Signal includes, for example, a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), or the like. In designing a synchronization signal in the fifth Generation mobile communication (5 th-Generation, 5G) technology, a low Peak to Average power ratio (PAPR) property and a good anti-frequency offset property need to be considered simultaneously to complete better time synchronization and initial access.

In a synchronization signal designed in a current Long Term Evolution (LTE) system, for example, a base station (evolved Node B, eNB) generates a primary synchronization signal, where the primary synchronization signal is used to transmit information of a physical layer cell identifier. The specific method comprises the following steps: the eNB associates the information of the physical layer cell identification with a Root Sequence Index (Root Sequence Index) u, and then codes to generate 1 synchronization signal Sequence d with the length of 62_uAnd (n) mapping the current cell identifier to a Resource Element (RE) corresponding to the PSS, wherein the UE can acquire the physical layer cell identifier information of the current cell by blindly detecting the primary synchronization sequence. Usually, the primary synchronization signal sequence is a complex sequence of length 62, and the primary synchronization signal sequence is a ZC sequence of length 63 (Zadoff-Chu )The root sequence index of the ZC sequence has 3 different values for indicating the information of the physical layer cell id in the physical layer cell id group, for example,

the primary synchronization signal may use a synchronization signal sequence with a length of 62, and the three different cell identification values respectively correspond to root sequence indexes, that is, sequences with u being 25,29 and 34.

For various system bandwidths (e.g., 5, 10, 15, 20MHz), the transmission bandwidth of the synchronization signal is the same, occupying a bandwidth of 1.08MHz in the center of the band. The signal occupies 62 sub-carriers, and two sides reserve 5 sub-carriers respectively as guard bands.

When designing the synchronization signal in the 5G technology, the length of the 5G synchronization signal may be greater than or equal to that in LTE, for example, the 5G synchronization signal needs to adopt a synchronization signal sequence with a length of 127 (127-length). In the prior art, a synchronization signal sequence and a root sequence index thereof designed in an LTE system cannot meet the requirements of low PAPR and better frequency offset resistance.

Disclosure of Invention

The embodiment of the invention provides a synchronous signal transmission method, a synchronous signal detection method, a base station and user equipment, which can obtain low PAPR and better frequency deviation resistance.

In order to solve the above technical problems, embodiments of the present invention provide the following technical solutions:

in a first aspect, an embodiment of the present invention provides a synchronization signal transmission method, including: a base station acquires a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (modN); the base station generates a synchronization signal sequence with the length of M according to the first root sequence index; and the base station maps the synchronization signal sequence with the length of M on M subcarriers and sends the synchronization signal sequence. In the embodiment of the invention, a synchronous signal sequence is generated by a first root sequence index, and as the first root sequence index is a root sequence index of a ZC sequence, ZC sequences with different root sequence indexes of the same length have good cross-correlation characteristics, and the cross-correlation value is close to zero, the synchronous signal sequence generated by the first root sequence index has the characteristic of low PAPR, in the embodiment of the invention, any root sequence index u in a set consisting of T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, a being an element in a subset of the root picking parameter set {3, 4, 5, 6, 7, 8 }. The frequency offset in signal transmission can bring about the time shift of the received signal, and when the time-shifted interval of the received signal is greater than or equal to the multipath time delay, the correct reception of the signal can be realized. The time shift length of the received signal is related to the value of the root sequence index of the ZC sequence, the root sequence index u in the embodiment of the application meets the root selection condition, when a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, the frequency offset peak value and the multipath peak value can be distinguished while the low PAPR is kept, and therefore the better frequency offset resistance characteristic is realized.

In one possible design, the ZC sequence includes: a first ZC sequence and a second ZC sequence; the base station generates a synchronization signal sequence with the length of M according to the first root sequence index, and the method comprises the following steps: the base station generates the synchronization signal sequence according to a first ZC sequence with a length of N1 and a second ZC sequence with a length of N2, wherein both N1 and N2 are less than M. Base station can pass through by length N₁And a first ZC sequence of length N₂Generates a synchronization signal sequence of length M, N₁And N₂Are smaller than M, and therefore, in some embodiments of the present invention, the first ZC sequence and the second ZC sequence may be subjected to short sequence concatenation, so as to generate a synchronization signal sequence of any length.

In one possible design, the ZC sequence includes: a first ZC sequence and a second ZC sequence; the base station maps the synchronization signal sequence with the length of M on M subcarriers, and the method comprises the following steps: the base station will have a length of N₁Is mapped to N of M sub-carriers₁On the sub-carriers, the length is N₂Is mapped to N of M subcarriers₂On subcarriers, the N₁And said N₂The sum is less than or equal to said M. Through the foregoing subcarrier mapping manner, the synchronization signal sequence may be sent to the user equipment through M subcarriers.

In one possible design, the obtaining, by the base station, a first root sequence index from a set of T root sequence indexes includes: and the base station acquires a first root sequence index from a set consisting of the T root sequence indexes according to the cell identification ID information. The base station can realize the acquisition of the first root sequence index through the cell identification, thereby providing the available first root sequence index for generating the synchronous signal sequence.

In a second aspect, an embodiment of the present invention further provides a synchronization signal detection method, including: the method comprises the steps that user equipment obtains a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N); the user equipment generates a synchronization signal sequence with the length of M according to the first root sequence index; and the user equipment processes the received signal by using the synchronization signal sequence with the length of M. In the embodiment of the present application, a synchronization signal sequence is generated by a first root sequence index, and since the first root sequence index is a root sequence index of a ZC sequence, ZC sequences with different root sequence indexes having the same length have good cross-correlation characteristics, and a cross-correlation value is close to zero, a synchronization signal sequence generated by the first root sequence index has a low PAPR, and in the embodiment of the present application, any one root sequence index u in a set of T root sequence indexes satisfies the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, a being an element in a subset of the root picking parameter set {3, 4, 5, 6, 7, 8 }. The frequency offset in signal transmission can bring about the time shift of the received signal, and when the time-shifted interval of the received signal is greater than or equal to the multipath time delay, the correct reception of the signal can be realized. The time shift length of the received signal is related to the value of the root sequence index of the ZC sequence, the root sequence index u in the embodiment of the application meets the root selection condition, when a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, the frequency offset peak value and the multipath peak value can be distinguished while the low PAPR is kept, and therefore the better frequency offset resistance characteristic is realized.

In one possible design, the ZC sequence includes: a first ZC sequence and a second ZC sequence; the user equipment generates a synchronization signal sequence with the length of M according to the first root sequence index, and the method comprises the following steps: the user equipment is N according to the length₁And a first ZC sequence of length N₂The second ZC sequence of (1) generates the synchronization signal sequence, the N₁And said N₂Are both less than said M. The user equipment can pass the channel with the length of N₁And a first ZC sequence of length N₂Generates a synchronization signal sequence of length M, so that the first ZC sequence and the second ZC sequence may be mapped to each other in some embodiments of the present inventionAnd carrying out short sequence cascade to generate a synchronous signal sequence with any length.

In one possible design, the ZC sequence includes: a first ZC sequence and a second ZC sequence; the user equipment processes the received signal by using the synchronization signal sequence with the length of M, and the method comprises the following steps: n of M subcarriers for the user equipment₁On a subcarrier, and N out of M subcarriers₂And processing the received signal by using the synchronization signal sequence with the length of M on the sub-carrier. N of user equipment in M sub-carriers₁N on and among the M subcarriers₂The processing of the synchronization signal sequence can be completed on the sub-carriers, so that the user equipment can obtain the signal sent by the base station.

In one possible design, the obtaining, by the ue, a first root sequence index from a set of T root sequence indexes includes: the user equipment obtains at least one root sequence index in a set formed by the T root sequence indexes as a first root sequence index. The user equipment can acquire at least one root sequence index in a set consisting of the T root sequence indexes as a first root sequence index in a blind detection mode, and an implementable scheme is provided for acquiring the first root sequence index.

In one possible design, the processing, by the ue, the received signal using the synchronization signal sequence with length M includes: and the user equipment performs correlation operation by using the synchronization signal with the length of M and the received signal. Through the correlation operation, the user equipment can obtain the signal transmitted by the base station.

In a possible design of the above method embodiment, a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }. The embodiment of the invention provides a specific numerical value of a, and the feasibility of the scheme is improved.

In a possible design of the above method embodiment, N is an odd number or a prime number, and the embodiment of the present invention provides a specific value of the ZC sequence length, thereby improving the implementability of the scheme.

In one possible design of the above method embodiment, when N is equal to M, the ZC sequence is a synchronization signal sequence; when the N is larger than the M, a truncation sequence of the ZC sequence is the synchronous signal sequence; when the N is less than the M, the cyclic extension sequence of the ZC sequence is the synchronization signal sequence. The ZC sequence or the sequence generated by the ZC sequence in the mode can be used for generating a synchronous signal sequence, and a specific embodiment is provided for generating the synchronous signal sequence.

In one possible design of the above method embodiment, when N is 61 and T is 3, the set of T root sequence indexes is any three of 20, 41, 15, and 46. The embodiment of the invention provides specific numerical values of T root sequence indexes, and improves the implementability of the scheme.

In one possible design of the above method embodiment, when N is 63 and T is 3, the set of T root sequence indexes is any three of 8, 55, 16, and 47. The embodiment of the invention provides specific numerical values of T root sequence indexes, and improves the implementability of the scheme.

In one possible design of the above method embodiment, when N is 127 and T is 3, the set of T root sequence indexes is any three of 42, 85, 32, and 95. The embodiment of the invention provides specific numerical values of T root sequence indexes, and improves the implementability of the scheme.

In one possible design of the foregoing method embodiment, the synchronization signal sequence includes: a primary synchronization signal sequence, or a secondary synchronization signal sequence. The embodiment of the invention provides a specific implementation mode of the synchronous signal sequence, and the implementability of the scheme is improved.

In a third aspect, an embodiment of the present invention further provides a base station, including: a processing module, configured to obtain a first root sequence index from a set of T root sequence indexes, where T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any root sequence index u in the set of T root sequence indexes satisfies a root selection condition as follows: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N); the processing module is configured to generate a synchronization signal sequence with a length of M according to the first root sequence index; the processing module is configured to map the synchronization signal sequence with the length of M onto M subcarriers; a sending module, configured to send the synchronization signal sequence with the length M mapped on the M subcarriers by the processing module.

In the third aspect of the present invention, the constituent modules of the base station may further perform the steps described in the foregoing first aspect and various possible implementations, for details, see the foregoing description of the first aspect and various possible implementations.

In a fourth aspect, an embodiment of the present invention further provides a user equipment, including: a processing module, configured to obtain a first root sequence index from a set of T root sequence indexes, where T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any root sequence index u in the set of T root sequence indexes satisfies a root selection condition as follows: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (modN); the processing module is configured to generate a synchronization signal sequence with a length of M according to the first root sequence index; and the processing module is used for processing the received signal by using the synchronization signal sequence with the length of M.

In a fourth aspect of the present invention, the component module of the user equipment may further perform the steps described in the foregoing second aspect and in various possible implementations, for details, see the foregoing description of the second aspect and in various possible implementations.

In a fifth aspect, an embodiment of the present invention further provides a base station, where the base station has a function of implementing a behavior of the base station in the foregoing method, and the function may be implemented by hardware, or may be implemented by hardware executing corresponding software. The hardware or software includes one or more modules corresponding to the above-described functions.

In one possible design, the structure of the base station includes a receiver and a transmitter, and the transmitter and the receiver are configured to support the base station to communicate with the user equipment, and to transmit or receive information or instructions related to the method described above to the user equipment. The base station may further comprise a memory and a processor configured to support the base station to perform corresponding functions in the above-described method, and to store programs and instructions necessary for the base station.

In a sixth aspect, an embodiment of the present invention further provides a user equipment, where the user equipment has a function of implementing a behavior of the user equipment in the above method design. The functions can be realized by hardware, and the functions can also be realized by executing corresponding software by hardware. The hardware or software includes one or more modules corresponding to the above-described functions. The modules may be software and/or hardware.

In one possible design, the structure of the user equipment includes a receiver, a processor, and a transmitter, where the transmitter and the receiver are configured to support the user equipment to communicate with the base station, and to transmit or receive information or instructions related to the method to or from the base station, and the processor is configured to support the base station to perform corresponding functions in the method. The base station may also include a memory for storing programs and instructions necessary for the base station.

Drawings

Fig. 1 is a schematic diagram of a system architecture to which a synchronization signal transmission method according to an embodiment of the present invention is applied;

fig. 2 is a schematic flow chart diagram illustrating a synchronization signal transmission method according to an embodiment of the present invention;

fig. 3-a is a schematic diagram of dealing with multipath interference by using time offset according to an embodiment of the present invention;

FIG. 3-b is a schematic diagram illustrating a frequency offset generated during signal transmission according to an embodiment of the present invention;

fig. 4 is a schematic flowchart illustrating a method for detecting a synchronization signal according to an embodiment of the present invention;

fig. 5 is a schematic flow chart illustrating another synchronization signal transmission method according to an embodiment of the present invention;

fig. 6 is a schematic flow chart illustrating another synchronization signal detection method according to an embodiment of the present invention;

fig. 7 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 8 is a schematic structural diagram of a user equipment according to an embodiment of the present invention;

fig. 9 is a schematic structural diagram of a base station according to an embodiment of the present invention;

fig. 10 is a schematic structural diagram of a user equipment according to an embodiment of the present invention.

Detailed Description

The embodiment of the invention provides a synchronous signal transmission method, a synchronous signal detection method, a base station and user equipment, which can realize low PAPR and better frequency deviation resistance.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

The terms "first," "second" (if any), and the like in the description and in the claims, as well as in the drawings, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and are merely descriptive of the invention in its embodiments for distinguishing between objects of the same nature. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of elements is not necessarily limited to those elements, but may include other elements not expressly listed or inherent to such process, method, article, or apparatus.

The following are detailed below.

First, a system architecture applied to the synchronization signal transmission method provided by the embodiment of the present invention is explained, and the embodiment of the present invention is applicable to a 5G communication system or a 4G communication system, for example, the embodiment of the present invention is applicable to a Long Term Evolution (LTE) system, a Wideband Code Division Multiple Access (W-CDMA) system, and the like. Referring to fig. 1, a schematic diagram of a system architecture applied to a synchronization signal transmission method according to an embodiment of the present invention is shown, where the system includes: the base station and the user equipment, wherein the user equipment may specifically be a mobile phone, a notebook, a tablet computer, and the like. Based on the system architecture provided by the embodiment of the invention, the base station can perform downlink transmission to the user equipment, for example, the user equipment under the base station sends a synchronous signal sequence. The user equipment may transmit uplink to the base station. The transmission herein may specifically refer to data transmission and control signaling transmission.

In some embodiments of the present invention, first, a method for transmitting a synchronization signal from a base station side is described, please refer to fig. 2, where the method for transmitting a synchronization signal according to an embodiment of the present invention may include:

201. the base station acquires a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N).

In the embodiment of the present invention, a base station first determines a set formed by T root sequence indexes, where the set includes the T root sequence indexes, the T root sequence indexes are root sequence indexes of a ZC sequence, and a value of T is a positive integer, for example, T may be greater than or equal to 1. After determining a set of T root sequence indices, a first root sequence index is obtained from the set, where the first root sequence index refers to one or some root sequence indices of the T root sequence indices, and for example, an arbitrary root sequence index may be selected from the T root sequence indices as the first root sequence index. The determination of the T root sequence indices is illustrated.

In some embodiments of the present invention, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any one root sequence index u in a set of T root sequence indexes satisfies the following root selection condition:

(a × u) mod N ═ 1, or (a × u) mod N ═ N-1,

wherein N is an integer greater than 1, u is an integer, mod represents a remainder operation from 0 to N-1, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following conditions: b ≠ c (mod N).

The meaning of the formula b ≠ c (mod N) is now exemplified. N is an integer greater than 1, u is an integer greater than or equal to 1 and less than N, and the values of a and u can be determined by the root selection condition. Any two root sequence indexes b and c in the set formed by the T root sequence indexes meet the following conditions: b is not equal to c (mod N), namely the result after the operation of bmod N is not equal to the result after the operation of cmodN, namely bmod N is not equal to cmod N, and b and c are not equal in the meaning of mod N. If b is c (mod N), the sequences determined by the two root sequence indexes are the same and not different sequences. In general, b ═ c (mod N) means that b and c are the same in the sense of mod N.

In some embodiments of the present invention, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and the root selection parameter set {3, 4, 5, 6, 7, 8} may include a plurality of subsets, for example, a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8}, then a may be an element of {3, 4} or {3, 4, 6, 8 }. The value of a may be selected from the root selection parameter set {3, 4, 5, 6, 7, 8} or a subset of the set, for example, the value of a may be 3, or 4, etc. Illustratively, the value of a may also be obtained from a set {3, 4, 5, 6, 7, 8, 9, 10} {3, 4, 5, 6, 7, 8, 9}, for example, the value of a may also be 9, or 10, and so on. The values of a, u, and N satisfy the root selection condition, and the values of u are illustrated in detail in the following embodiments.

In an embodiment of the present invention, in step 201, the base station obtains a first root sequence index from a set of T root sequence indexes, including:

a1, the base station obtains the first root sequence index from the set of T root sequence indexes u according to the cell Identity (ID) information.

After the base station determines a set of T root sequence indexes, the base station may select a first root sequence index from the set of T root sequence indexes according to a mapping relationship between a cell ID and the root sequence index, where the cell ID is specifically a physical cell identity (physical cell identity), for example.

In some embodiments of the present invention, the value of N may be all integers. The other value mode is as follows: n is odd or prime. The value of N can be determined in combination with the need to generate ZC sequences in a specific scenario.

202. And the base station generates a synchronization signal sequence with the length of M according to the first root sequence index.

In the embodiment of the invention, after the base station selects the first root sequence index of the ZC sequence, the first root sequence index can be used for generating a synchronization signal sequence with the length of M, and the value of M can be determined by combining the requirement of generating the synchronization sequence under a specific scene. In some embodiments of the invention, the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

In some embodiments of the present invention, a generation manner of the synchronization signal sequence with the length M is illustrated, for example, the synchronization signal sequence is generated by the following manner:

b1, when N is equal to M, ZC sequence is a synchronous signal sequence;

b2, when N is larger than M, the truncation sequence of the ZC sequence is a synchronous signal sequence;

and B3, when N is less than M, the cyclic extension sequence of the ZC sequence is a synchronous signal sequence.

After the base station acquires the first root sequence index, the base station may generate a synchronization signal sequence with a length of M through a ZC sequence with a length of N, and for different values between N and M, the synchronization signal sequence may be generated in the above three ways.

In some embodiments of the invention, the ZC sequence comprises: a first ZC sequence and a second ZC sequence. Step 202, the base station generates a synchronization signal sequence with length M according to the first root sequence index, including:

c1, the base station is N according to the length₁And a first ZC sequence of length N₂Generates a synchronization signal sequence, N₁And N₂Are both less than M.

Specifically, the ZC sequence with length N may include ZC sequences with multiple lengths, for example, as follows, the first root sequence index is a root sequence index of the ZC sequence, and the ZC sequence may include: a first ZC sequence and a second ZC sequence, the length of the first ZC sequence being N₁The length of the second ZC sequence is N₂E.g. N₁Adding N₂Equal to N, e.g. N₁Is equal to N₂And are all equal to N/2. N is a radical of₁And N₂The value may be specifically selected in combination with an application scenario, and is not limited herein. Base station can pass through by length N₁And a first ZC sequence of length N₂Generates a synchronization signal sequence of length M, N₁And N₂Are smaller than M, and therefore, in some embodiments of the present invention, the first ZC sequence and the second ZC sequence may be subjected to short sequence concatenation, so as to generate a synchronization signal sequence of any length.

For example, the synchronization signal sequence may be a ZC sequence, and the ZC sequence has good autocorrelation, that is, an arbitrary ZC sequence is uncorrelated with a sequence other than itself obtained by cyclic shifting the ZC sequence by n bits, that is, a correlation value is zero. ZC sequences of different indices of the same length may have good cross-correlation properties with cross-correlation values close to zero. The ZC sequence has a low PAPR, and remains as the ZC sequence after Fast Fourier Transform (FFT) or Inverse Fast Fourier Transform (IFFT). ZC sequences can be represented as follows:

when N is an odd number, the following expression is adopted:

when N is an even number, the following expression is adopted:

wherein, in the above expression, N is the length of the ZC sequence, u is a prime natural number with N, and 0 < u < N, which is a root sequence index of the ZC sequence, different u values correspond to different ZC sequences, and L is an integer and may take a zero value. For example, when N is 11, u may take a value of 1 to 10. It should be noted that u may also be any integer, but if the two integer indices are equal after the modN operation, the corresponding sequences are the same sequence.

In some embodiments of the present invention, the synchronization signal sequence is a ZC sequence or a sequence generated by a ZC sequence, and in particular, the synchronization signal sequence may be obtained by cyclically extending or truncating the ZC sequence. Further, the cyclic shift sequence of ZC sequence in time domain can be generated, assuming that the sequence is { s_iI is 0,1,2,.., P-1, and the time-domain cyclic shift sequence is { s }_ie^2πijαi is 0,1,2,.., P-1}, α is a real number, j is an imaginary unit, different time domain cyclic shift sequences of the ZC sequence have the same root sequence index, and the length of the synchronization signal in the 5G system may be any prime value, such as 23, 31, 61, length 127, etc., and is not limited to thisAnd (4) determining. And synchronization signal sequences longer than the ZC sequence of length 63 in the LTE system, such as a ZC sequence of length 127, may also be considered. The synchronization signal sequence with any length in the embodiment of the invention meets the following properties: low PAPR property and superior frequency offset resistance.

Referring to fig. 3-a, fig. 3-a is a schematic diagram of using time offset to cope with multipath interference, fig. 3-b is a schematic diagram of generating frequency offset in the signal transmission process. The frequency offset in signal transmission may cause a shift of a received signal in time, for example, a frequency offset (hereinafter also referred to as frequency offset) is generated in the transmission process of the subcarrier 1 and the subcarrier 2, and when an interval after the received signal is deflected or shifted in time is greater than or equal to a multipath time delay, correct reception of the signal can be achieved. The length of the time shift of the received signal is related to the value of the root sequence index of the ZC sequence, e.g., the value of the one-sided time shift of the received signal is a function of the root sequence index u and the length N. For example, the shift value delta _ T is p × u, the unit of multipath delay is T/N, T may be the length of an Orthogonal Frequency Division Multiplexing (OFDM) symbol, p is greater than 0, p represents positive Frequency offset, and-p represents negative Frequency offset. In order to overcome the frequency offset of signal transmission and to combat the multipath interference of fading channel, the root sequence index u should be selected to satisfy: n-t₁＞(±p×u)mod N＞t₁，t₁And the unit of the multipath time delay is T/N. Assuming that p is 1 and the multipath delay is N/10, 9N/10 > (p.u) mod N > N/10. In addition, it is necessary to distinguish between positive frequency offset and negative frequency offset, and therefore, it is required that the cyclic shift interval between (-p · u) mod N and (p · u) mod N is sufficiently large, and the cyclic shift interval between multipath windows in the case of positive and negative frequency offsets is sufficiently large, so that there is no overlap between multipaths, for example, larger than multipath time delay. The cyclic shift interval for two values x, y is defined as min { (x-y) mod N, N- ((x-y) mod N) }.

Illustratively, if u satisfies (a × u) mod N is 1, or (a × u) mod N is N-1, then p is +1 or p is-1, and the delay caused by the frequency offset is approximately 1/a of the whole symbol time T, so that a relatively small a is selected, and multipath and frequency offset can be distinguished to different shifts, and at the same time, a sequence with a relatively low PAPR is selected. However, the sequence corresponding to a-1 and a-2 cannot effectively distinguish between frequency offset and multipath-induced shift. In the case of ZC sequences without oversampling, the PAPR is zero dB, but the PAPR with oversampling differs depending on the sequence.

Then, the values of u are illustrated for the values of different N, and u satisfying the above conditions and having a lower PAPR can be selected as follows:

for example, see table 1 below for an example description of N ═ 61:

thus, the set of a is {3, 4}, {3, 4, 6, 5}, a subset of the set of a being the set of a itself {3, 4}, {3, 4, 6, 5 }.

For another example, see the following example 2:

for another example, see example specification in table 3 below:

thus, the set of a is {3, 4}, {3, 4, 7}, {3, 4, 8}, {3, 4, 7, 8}, a subset of the set of a being the set of a itself {3, 4}, {3, 4, 7}, {3, 4, 8}, {3, 4, 7, 8 }.

Assuming that the length of the ZC sequence is N and the root sequence index (assuming that its value is denoted by u) that satisfies the above selection principle is any one of a plurality of values described below:

a u value satisfying (3 × u) mod N ═ 1 or (3 × u) mod N ═ N-1, where 1< ═ u < ═ N;

a u value satisfying (4 × u) mod N ═ 1 or (4 × u) mod N ═ N-1, where 1< ═ u < ═ N;

a u value satisfying (6 × u) mod N ═ 1 or (6 × u) mod N ═ N-1, where 1< ═ u < ═ N;

a u value satisfying (8 × u) mod N ═ 1 or (8 × u) mod N ═ N-1, where 1< ═ u < ═ N;

in addition to the above values, a u value of (5 × u) mod N ═ 1 or (5 × u) mod N ═ N-1 is satisfied, where 1< ═ u < ═ N; and a u value satisfying (7 × u) mod N ═ 1 or (7 × u) mod N ═ N-1, where 1< ═ u < ═ N can also be considered without being particularly limited.

Further, a-9 and a-11 may be included in the parameter set for determining u.

Further, a-10 may be included in the parameter set for determining u.

Further, a-12 may be included in the parameter set for determining u.

Further, a-13 may be included in the set of parameters for determining u.

Illustratively, the root-selection parameter set of a is {3, 4, 5, 6, 7, 8}, {3, 4, 5, 6, 7, 8, 9, 10, 12, 13 }.

In some embodiments of the present invention, when N is 61 and T is 3, the set of T root sequence indices is any three of 20, 41, 15, and 46. When T is 4, the elements of the set of T root sequence indices are 20, 41, 15, and 46. The set of a is 3, 4, and a subset of the set of a is 3, 4, 6, 3, 4, 5.

Next, a synchronization signal sequence d of length 60 will be described by taking N61 as an example_u(n) when implemented with a ZC sequence of length 61 with the center element removed, can be expressed as:

d_u(n)＝z_u(n),n＝0,1,2,...,29

d_u(n)＝z_u(n+1),n＝30,31,...,59

wherein z is_u(n) is an element of a length-61 ZC sequence with a root sequence index u.

The u values satisfying the above-described (3 × u) mod N ═ 1 or (3 × u) mod N ═ 1 are 20 and 41, respectively, and the u values satisfying the above-described (4 × u) mod N ═ 1 or (4 × u) mod N ═ 1 are 15 and 46, respectively. Assuming that the number of root sequence indexes to be selected is 3, when N is 61, the root sequence index of the synchronization signal sequence with the length of 61 is any one of 20, 41, 15, and 46. When T is 3, the values of the 3 root sequence indexes satisfy the following table 4:

	u
		0	20
1	41
		2	15

in some embodiments of the present invention, when N is 63 and T is 3, the set of T root sequence indices is any three of 8, 55, 16, and 47. When T is 4, the elements of the set of T root sequence indices are 8, 55, 16, 47. The set of a is 4, 8, and a subset of the set of a is 4, 8.

Next, a sync signal sequence d of length 62 will be described by taking N63 as an example_u(n) when implemented by removing center element using ZC sequence of length 63It can be expressed as:

d_u(n)＝z_u(n),n＝0,1,2,...,30

d_u(n)＝z_u(n+1),n＝31,32,...,61

wherein z is_u(n) is an element of a length-63 ZC sequence with a root sequence index u.

When N is 63, the root sequence index of the ZC sequence is any one of 8, 55, 16, and 47. When T is 3, the values of the 3 root sequence indexes satisfy the following table 5:

	u
		0	8
1	55
		2	16

in some embodiments of the present invention, when N is 127 and T is 3, the set of T root sequence indices is any three of 42, 85, 32, and 95. When T is 4, the elements of the set of T root sequence indices are 42, 85, 32, 95. The set of a is {3, 4}, and a subset of the set of a is {3, 4 }.

Next, a length 126 synchronization signal sequence d will be described by taking N as an example 127_u(n) when implemented with a ZC sequence of length 127, can be expressed as:

d_u(n)＝z_u(n),n＝0,1,2,...,62

d_u(n)＝z_u(n+1),n＝63,64,...,125

wherein z is_u(n) is an element of a length 127 ZC sequence with a root sequence index u.

The u values satisfying the above-described (3 × u) mod N ═ 1 or (3 × u) mod N ═ 1 are 42 and 85, respectively, and the u values satisfying the above-described (4 × u) mod N ═ 1 or (4 × u) mod N ═ 1 are 32 and 95, respectively. Assuming that the number of root sequence indexes to be selected is 3, the values of the selectable root sequence indexes are any three of 42, 85, 32, and 95, and the values of the 3 root sequence indexes satisfy the following table 6:

	u
		0	32
1	95
		2	42

in addition to the above-mentioned synchronization signal sequences of two lengths, other synchronization signal sequences of arbitrary length are not excluded, which follow a design principle similar to the above-mentioned synchronization signal sequences of length 61 and length 127. And will not be described in detail herein. Other values of N may also be 11, 19, 31, 37, 41, etc., and are not limited herein.

In some embodiments of the present invention, the ZC sequence or the sequence generated by the ZC sequence has a good PAPR, but the PAPR of the oversampled time domain signal may vary depending on the root sequence index. From the list of N-61, N-63, and N-127, it can be seen that the PAPR is arranged in order from low to high according to the change of the root sequence index, and in the embodiment of the present invention, the root sequence index with the lowest PAPR needs to be selected as much as possible.

Any root sequence index u in a set consisting of T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N). The one subset may be any non-empty subset of the root selection parameter set, including the root selection parameter set itself.

Further, the T root sequence index sets satisfy the following characteristics: for any element a in the subset, one element u in a set formed by the T root sequence indexes meets a root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1. a is a parameter used to determine the root sequence index u, uxa mod N ═ 1, or uxa mod N ═ N-1. In some embodiments of the present invention, the set of a may be the smallest K positive integer values among positive integers satisfying N ═ 1(mod a) or N ═ 1(mod a), and a is not equal to 1,2, 1,2 cannot be selected since it cannot be distinguished that a shift is caused by a frequency offset. K is a positive integer, such as 2, 3, 4, or 5, and so forth. mod N equals the values of two a, the determined root sequence indices are the same. Therefore a may be required to be less than N. The value of K may be chosen to be relatively small so that a is not too large, for example so that a is less than N/2.

For example, when N is 61, all positive integers a less than N and not 1 or 2 satisfying N1 (mod a) or N-1 (mod a) are {3, 4, 5, 6, 10, 12, 15, 20, 30, 31, 60}, and 1 or 2 cannot be an element in the set of a. Illustratively, K is 2, then the set of a is {3, 4 }. K4, then the set of a is {3, 4, 5, 6}, and a subset of the set of a may be {3, 4}, {3, 4, 6}, {3, 4, 5, 6}, considering the order of PAPR from low to high. K is 5, the set of a is {3, 4, 5, 6, 10}, and so on.

Illustratively, when N is 63, all positive integers a less than N and not 1,2 satisfying N1 (mod a) or N-1 (mod a) are {4, 8, 16, 31, 32, 62}, and 2 cannot be an element in the set of a. For another example, if K is 2, the set of a is {4, 8 }.

Illustratively, when N is 127, all positive integers a less than N that satisfy N-1 (mod a) or N-1 (mod a) are {3, 4, 6, 7, 8, 9, 14, 16, 18, 21, 32, 42, 63, 64, 126 }. When K is 2, the set of a is {3, 4}, and K is 3, the set of a is {3, 4, 6}, and a subset of the set of a is {3, 6}, {3, 4}, and {4, 6 }. K4, the set of a is {3, 4, 6, 7}, and a subset of the set of a may be {3, 4, 6}, {3, 4, 7}, {4, 6, 7}, and {3, 6, 7 }. K5, the set of a is {3, 4, 6, 7, 8}, a subset of the set of a may be any subset of {3, 4, 6, 7, 8}, and a subset of the set of a may be {3, 4}, or {3, 4, 7}, {3, 4, 7, 8}, and {3, 4, 7, 8, 6}, in view of the order of the corresponding PAPR from low to high, and the number of required root sequence indices. When K is 5, the set of a is {3, 4, 6, 7, 8, 9 }.

Illustratively, when N is 113, all a's that satisfy N1 (mod a) or N-1 (mod a) positive integers smaller than N and are not 1 or 2 at the same time are {3, 4, 6, 7, 8, 14, 16, 19, 28, 38, 56, 57, 112 }. Therefore, when K is 2, the set of root selection parameters a is {3, 4 }. When K is 3, the set of root selection parameters a is {3, 4, 6 }. When K is 4, the set of root selection parameters a is {3, 4, 6, 7 }. When K is 5, the set of root selection parameters a is {3, 4, 6, 7, 8 }. Through PAPR simulation verification, when the values of a are sequentially the elements in the set {4, 3, 7, 6, 8}, the PAPR is arranged from low to high.

For example, when N is 63, the set of a used to determine the T root sequence indexes may be {4, 8, 5, 13}, and the subset of the set of a is {4, 8}, {4, 5}, {8, 5}, {4, 13}, {8, 13}, {4, 8, 5}, {4, 8, 13}, {8, 5, 13}, {4, 8, 5, 13 }. Or when N63, the subset of a set of a used to determine the T root sequence indices includes at least one further value other than a 5, a 13, belonging to {4, 8}, or belonging to one of the smallest K positive integer values that satisfy N-1 (mod a) or N-1 (mod a), e.g., K-2, or K-3. Unlike the set of root sequence indices in the LTE system, the subset of the corresponding set of a in the LTE system is {5, 13 }.

It should be noted that, based on the foregoing examples, in the embodiments of the present invention, a better or more sequence may also be adopted, which is not described herein one by one, and the above method for determining T root sequence indexes may be applied to the foregoing embodiments of the present invention.

In the embodiment of the invention, the effect of low PAPR and better frequency deviation resistance characteristic support can be realized simultaneously by carrying out reasonable root selection design according to the length N of the synchronous signal sequence. Therefore, the time frequency coarse synchronization of the synchronization signal can be better realized.

203. And the base station maps the synchronization signal sequence with the length of M on the M subcarriers and transmits the synchronization signal sequence.

In the embodiment of the present invention, after the base station generates the synchronization signal sequence with the length M, the base station may use M subcarriers to transmit the synchronization signal sequence with the length M, for example, the base station transmits the synchronization signal sequence with the length M on the M subcarriers in a broadcast manner. For example, M subcarriers are distributed at equal intervals continuously, and in this implementation scenario, the base station maps a synchronization signal sequence with a length of M on the M subcarriers distributed at equal intervals continuously.

In some embodiments of the present invention, step 203, the base station maps a synchronization signal sequence with a length of M on M subcarriers, including:

d1, the base station maps the synchronization signal sequence with the length of M on M subcarriers distributed at continuous equal intervals; or the like, or, alternatively,

d2, the base station maps the synchronization signal sequence with the length of M on M sub-carriers except the center sub-carrier.

The base station may adopt multiple ways when mapping the synchronization signal sequence on M subcarriers, for example, the base station maps the synchronization signal sequence with length M on M subcarriers that are continuously distributed at equal intervals, and for example, the base station maps the synchronization signal sequence with length M on M subcarriers except for the center subcarrier, and the specific mapping way depends on an application scenario, which is not limited herein.

In some embodiments of the invention, the ZC sequence comprises: a first ZC sequence and a second ZC sequence, the length of the first ZC sequence being N₁The length of the second ZC sequence is N₂Step 203, the base station maps the synchronization signal sequence with length M on M subcarriers, including:

e1, the base station has the length of N₁Is mapped to N of M sub-carriers₁On the sub-carriers, the length is N₂Is mapped to N of M subcarriers₂On sub-carriers, N₁And N₂The sum is less than or equal to M.

The ZC sequence with length N may specifically include multiple types of ZC sequences, and may include, for example, as follows: the first ZC sequence and the second ZC sequence, the base station can adopt various modes when mapping the synchronous signal sequence on M sub-carriers, for example, the base station maps the length to be N₁Is mapped to N of M sub-carriers₁On the sub-carriers, the length is N₂Is mapped to N of M subcarriers₂On the subcarriers.

As can be seen from the foregoing illustration, in the embodiment of the present application, the synchronization signal sequence is generated by the first root sequence index, and since the first root sequence index is the root sequence index of the ZC sequence, ZC sequences with different root sequence indexes having the same length have good cross-correlation properties, and the cross-correlation value is close to zero, the synchronization signal sequence generated by the first root sequence index has a low PAPR property, in the embodiment of the present application, any root sequence index u in the set of T root sequence indexes satisfies the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, a being an element in a subset of the root picking parameter set {3, 4, 5, 6, 7, 8 }. The frequency offset in signal transmission can bring about the time shift of the received signal, and when the time-shifted interval of the received signal is greater than or equal to the multipath time delay, the correct reception of the signal can be realized. The time shift length of the received signal is related to the value of the root sequence index of the ZC sequence, the root sequence index u in the embodiment of the application meets the root selection condition, when a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, the frequency offset peak value and the multipath peak value can be distinguished while the low PAPR is kept, and therefore the better frequency offset resistance characteristic is realized.

The foregoing embodiment describes a synchronization signal transmission method provided by the embodiment of the present invention from a base station side, and next introduces a synchronization signal detection method provided by the embodiment of the present invention from a user equipment side, please refer to fig. 4, where the synchronization signal detection method provided by the embodiment of the present invention includes:

401. the user equipment acquires a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N).

In some embodiments of the present invention, a subset of the root pick parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

In some embodiments of the invention, N is odd or prime.

In some embodiments of the invention, the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

h1, when N is equal to M, ZC sequence is synchronous signal sequence;

h2, when N is larger than M, the truncation sequence of the ZC sequence is a synchronous signal sequence;

h3, when N is less than M, the cyclic extension sequence of ZC sequence is synchronous signal sequence.

For the description of the root selection condition and the first root sequence index, refer to the description of the foregoing embodiments, and are not described herein again.

In some embodiments of the present invention, step 401, acquiring, by a user equipment, a first root sequence index from a set of T root sequence indexes, includes:

f1, the user equipment obtains at least one root sequence index in the set formed by the T root sequence indexes as a first root sequence index.

The user equipment may obtain at least one root sequence index in a set of T root sequence indexes as a first root sequence index in a blind detection manner, for example, the user equipment obtains all root sequence indexes in the set of T root sequence indexes as the first root sequence index, and for example, the user equipment obtains a part of root sequence indexes in the set of T root sequence indexes as the first root sequence index, a specific implementation manner depends on an application scenario, and is not limited herein. For example, in the case of target cell search, the user equipment may determine a partial root sequence index as a first root sequence index according to information of the target cell.

402. And the user equipment generates a synchronization signal sequence with the length of M according to the first root sequence index.

In some embodiments of the invention, a ZC sequence comprises: a first ZC sequence and a second ZC sequence.

Step 402, the user equipment generates a synchronization signal sequence with length M according to the first root sequence index, including:

i1, the user equipment is N according to the length₁And a first ZC sequence of length N₂Generates a synchronization signal sequence, N₁And N₂Are both less than M.

In some embodiments of the present invention, when N is 61 and T is 3, the set of T root sequence indices is any three of 20, 41, 15, and 46.

In some embodiments of the present invention, when N is 63 and T is 3, the set of T root sequence indices is any three of 8, 55, 16, and 47.

In some embodiments of the present invention, when N is 127 and T is 3, the set of T root sequence indices is any three of 42, 85, 32, and 95.

403. The user equipment processes the received signal using a synchronization signal sequence of length M.

In some embodiments of the present invention, the step 403, the ue processes the received signal by using a synchronization signal sequence with length M, including:

j1, the user equipment uses the synchronization signal sequence with length M to process the received signal on the M continuous sub-carriers distributed at equal intervals;

or the like, or, alternatively,

j2, the user equipment processes the received signal on M sub-carriers except the center sub-carrier by using the synchronization signal sequence with length M.

In some embodiments of the invention, a ZC sequence comprises: a first ZC sequence and a second ZC sequence;

step 403, the ue processes the received signal by using the synchronization signal sequence with length M, including:

k1, N of user equipment in M sub-carriers₁On a subcarrier, and N out of M subcarriers₂And processing the received signals on the subcarriers by using a synchronization signal sequence with the length of M.

l1, the ue performs correlation operation using the length M synchronization signal and the received signal.

Fig. 2 illustrates a synchronization signal transmission method according to an embodiment of the present invention, and next, another synchronization signal transmission method according to an embodiment of the present invention is described from a base station side, please refer to fig. 5, where the synchronization signal transmission method according to an embodiment of the present invention includes:

501. the base station generates a synchronization signal sequence with the length of M according to a unique first root sequence index, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and a first root sequence index u meets the following root selection conditions: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, and a is an element in a subset of the following root selection parameter sets {3, 4, 5, 6, 7, 8 }.

In the embodiment of the present invention, different from the foregoing embodiment shown in fig. 2, a base station does not need to obtain a first root sequence index from a set of T root sequence indexes, where the first root sequence index is a unique root sequence index, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set of T root sequence indexes satisfies the following root selection condition:

(a × u) mod N ═ 1, or (a × u) mod N ═ N-1,

where N is an integer greater than 1, u is an integer, mod represents a remainder operation with a remainder from 0 to N-1, and a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8 }. For example, N is an integer greater than 1, u is an integer greater than or equal to 1 and less than N, and the values of a and u may be determined by the root selection condition.

502. And the base station maps the synchronization signal sequence with the length of M on the M subcarriers and transmits the synchronization signal sequence.

See the detailed description of the embodiment shown in fig. 2, which is not repeated herein.

Fig. 4 illustrates a synchronization signal detection method according to an embodiment of the present invention, and next, another synchronization signal detection method according to an embodiment of the present invention is described from a user equipment side, please refer to fig. 6, where the synchronization signal detection method according to an embodiment of the present invention includes:

601. the user equipment generates a synchronization signal sequence with the length of M according to a unique first root sequence index, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and the first root sequence index u meets the following root selection conditions: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, mod represents a remainder operation with a remainder from 0 to N-1, and a is an element in a subset of the root pick parameter set {3, 4, 5, 6, 7, 8 };

602. the user equipment processes the received signal using a synchronization signal sequence of length M.

See the detailed description of the embodiment shown in fig. 4, which is not repeated herein.

As can be seen from the illustration of fig. 5 and fig. 6, in the embodiment of the present application, the synchronization signal sequence is generated by the first root sequence index, since the first root sequence index is the root sequence index of the ZC sequence, ZC sequences with different root sequence indexes of the same length have good cross-correlation characteristics, and the cross-correlation value is close to zero, the synchronization signal sequence generated by the first root sequence index has a low PAPR, and the first root sequence index u satisfies the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, a being an element in a subset of the root picking parameter set {3, 4, 5, 6, 7, 8 }. The frequency offset in signal transmission can bring about the time shift of the received signal, and when the time-shifted interval of the received signal is greater than or equal to the multipath time delay, the correct reception of the signal can be realized. The time shift length of the received signal is related to the value of the root sequence index of the ZC sequence, the root sequence index u in the embodiment of the application meets the root selection condition, when a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, the frequency offset peak value and the multipath peak value can be distinguished while the low PAPR is kept, and therefore the better frequency offset resistance characteristic is realized.

It should be noted that, for simplicity of description, the above-mentioned method embodiments are described as a series of acts or combination of acts, but those skilled in the art will recognize that the present invention is not limited by the order of acts, as some steps may occur in other orders or concurrently in accordance with the invention. Further, those skilled in the art should also appreciate that the embodiments described in the specification are preferred embodiments and that the acts and modules referred to are not necessarily required by the invention.

To facilitate a better implementation of the above-described aspects of embodiments of the present invention, the following also provides relevant means for implementing the above-described aspects.

Referring to fig. 7, a base station 700 according to an embodiment of the present invention includes: a processing module 701 and a sending module 702, wherein,

a processing module 701, configured to obtain a first root sequence index from a set of T root sequence indexes, where T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any root sequence index u in the set of T root sequence indexes satisfies a root selection condition as follows: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N);

the processing module 701 is configured to generate a synchronization signal sequence with a length of M according to the first root sequence index;

the processing module 701 is configured to map the synchronization signal sequence with the length of M on M subcarriers;

a sending module 702, configured to send the synchronization signal sequence with the length M mapped on the M subcarriers by the processing module.

In some embodiments of the present invention, a subset of the set of root selection parameters {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

In some embodiments of the invention, the N is odd or prime.

In some embodiments of the present invention, the,

when the N is equal to the M, the ZC sequence is the synchronization signal sequence;

when the N is larger than the M, a truncation sequence of the ZC sequence is the synchronous signal sequence;

when the N is less than the M, the cyclic extension sequence of the ZC sequence is the synchronization signal sequence.

In some embodiments of the present invention, the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

the processing module is specifically configured to be N according to length₁And a first ZC sequence of length N₂The second ZC sequence of (1) generates the synchronization signal sequence, the N₁And said N₂Are both less than said M.

the processing module is specifically used for converting the length into N₁Is mapped to N of M sub-carriers₁On the sub-carriers, the length is N₂Is mapped to N of M subcarriers₂On subcarriers, the N₁And said N₂The sum is less than or equal to said M.

In some embodiments of the present invention, when N is 61 and T is 3, the set of T root sequence indexes is any three of 20, 41, 15, and 46.

In some embodiments of the present invention, when N is 127 and T is 3, the set of T root sequence indexes is any three of 42, 85, 32, and 95.

In some embodiments of the present invention, the processing module is specifically configured to obtain the first root sequence index from a set of T root sequence indexes according to the cell identification ID information.

Referring to fig. 8, a user equipment 800 according to an embodiment of the present invention may include: the processing block 801, wherein,

a processing module 801, configured to obtain a first root sequence index from a set of T root sequence indexes, where T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any root sequence index u in the set of T root sequence indexes satisfies a root selection condition as follows: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N);

the processing module 801 is configured to generate a synchronization signal sequence with a length M according to the first root sequence index;

the processing module 801 is configured to process the received signal by using the synchronization signal sequence with the length M.

In some embodiments of the invention, the N is odd or prime.

In some embodiments of the present invention, the,

when the N is equal to the M, the ZC sequence is a synchronization signal sequence;

when the N is larger than the M, a truncation sequence of the ZC sequence is the synchronous signal sequence; when the N is less than the M, the cyclic extension sequence of the ZC sequence is the synchronization signal sequence.

the processing module is used for obtaining the length N₁And a first ZC sequence of length N₂The second ZC sequence of (1) generates the synchronization signal sequence, the N₁And said N₂Are both less than said M.

the processing module is specifically configured to N out of M subcarriers₁On a subcarrier, and N out of M subcarriers₂And processing the received signal by using the synchronization signal sequence with the length of M on the sub-carrier.

In some embodiments of the present invention, the processing module is specifically configured to obtain at least one root sequence index in a set of T root sequence indexes as a first root sequence index.

In some embodiments of the present invention, the processing module is specifically configured to perform a correlation operation using the synchronization signal with the length M and the received signal.

It should be noted that, because the contents of information interaction, execution process, and the like between the modules/units of the apparatus are based on the same concept as the method embodiment of the present invention, the technical effect brought by the contents is the same as the method embodiment of the present invention, and specific contents may refer to the description in the foregoing method embodiment of the present invention, and are not described herein again.

An embodiment of the present invention further provides a computer storage medium, where the computer storage medium stores a program, and the program executes some or all of the steps described in the above method embodiments.

Referring to fig. 9, another base station according to an embodiment of the present invention is described, in which a base station 900 includes:

a receiver 901, a transmitter 902, a processor 903 and a memory 904 (wherein the number of processors 903 in the base station 900 may be one or more, one processor is taken as an example in fig. 9). In some embodiments of the present invention, the receiver 901, the transmitter 902, the processor 903 and the memory 904 may be connected by a bus or other means, wherein the connection by the bus is exemplified in fig. 9.

The memory 904 may include both read-only memory and random-access memory, and provides instructions and data to the processor 903. A portion of Memory 904 may also include Non-volatile random Access Memory (NVRAM). The memory 904 stores an operating system and operating instructions, executable modules or data structures, or a subset or an expanded set thereof, wherein the operating instructions may include various operating instructions for performing various operations. The operating system may include various system programs for implementing various basic services and for handling hardware-based tasks.

The processor 903 controls the operation of the base station, and the processor 903 may also be referred to as a Central Processing Unit (CPU). In a particular application, the various components of the base station are coupled together by a bus system that may include a power bus, a control bus, a status signal bus, etc., in addition to a data bus. For clarity of illustration, the various buses are referred to in the figures as a bus system.

The method disclosed by the above embodiments of the present invention may be applied to the processor 903, or implemented by the processor 903. The processor 903 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be performed by integrated logic circuits of hardware or instructions in the form of software in the processor 903. The processor 903 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, discrete hardware component. The various methods, steps and logic blocks disclosed in the embodiments of the present invention 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 invention 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 the memory 904, and the processor 903 reads information in the memory 904 and performs the steps of the above method in combination with hardware thereof.

The receiver 901 may be used to receive input numeric or character information and generate signal inputs related to the relevant settings and function control of the base station, the transmitter 902 may include a display device such as a display screen, and the transmitter 902 may be used to output numeric or character information through an external interface.

In this embodiment of the present invention, the processor 903 is configured to execute the synchronization signal transmission method executed by the base station.

Referring to another ue provided in the embodiment of the present invention, referring to fig. 10, a ue 1000 includes:

a receiver 1001, a transmitter 1002, a processor 1003 and a memory 1004 (wherein the number of processors 1003 in the user equipment 1000 may be one or more, one processor is taken as an example in fig. 10). In some embodiments of the present invention, the receiver 1001, the transmitter 1002, the processor 1003 and the memory 1004 may be connected by a bus or other means, wherein the connection by the bus is exemplified in fig. 10.

The memory 1004 may include a read-only memory and a random access memory, and provides instructions and data to the processor 1003. A portion of the memory 1004 may also include NVRAM. The memory 1004 stores an operating system and operating instructions, executable modules or data structures, or a subset or an expanded set thereof, wherein the operating instructions may include various operating instructions for performing various operations. The operating system may include various system programs for implementing various basic services and for handling hardware-based tasks.

The processor 1003 controls the operation of the user equipment, which processor 1003 may also be referred to as a CPU. In a particular application, the various components of the user device are coupled together by a bus system that may include a power bus, a control bus, a status signal bus, etc., in addition to a data bus. For clarity of illustration, the various buses are referred to in the figures as a bus system.

The method disclosed in the above embodiments of the present invention may be applied to the processor 1003 or implemented by the processor 1003. The processor 1003 may be an integrated circuit chip having signal processing capabilities. In implementation, the steps of the above method may be implemented by integrated logic circuits of hardware or instructions in the form of software in the processor 1003. The processor 1003 may be a general purpose processor, DSP, ASIC, FPGA or other programmable logic device, discrete gate or transistor logic device, discrete hardware component. The various methods, steps and logic blocks disclosed in the embodiments of the present invention 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 invention 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 the memory 1004, and the processor 1003 reads the information in the memory 1004, and completes the steps of the method in combination with the hardware thereof.

In this embodiment of the present invention, the processor 1003 is configured to execute the synchronization signal detection method executed by the ue side.

It should be noted that the above-described embodiments of the apparatus are merely schematic, where the units described as separate parts may or may not be physically separate, and the parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on multiple network units. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution of the present embodiment. In addition, in the drawings of the embodiment of the apparatus provided by the present invention, the connection relationship between the modules indicates that there is a communication connection between them, and may be specifically implemented as one or more communication buses or signal lines.

Through the above description of the embodiments, those skilled in the art will clearly understand that the present invention may be implemented by software plus necessary general hardware, and may also be implemented by special hardware including special integrated circuits, special CPUs, special memories, special components and the like. Generally, functions performed by computer programs can be easily implemented by corresponding hardware, and specific hardware structures for implementing the same functions may be various, such as analog circuits, digital circuits, or dedicated circuits. However, the implementation of a software program is a more preferable embodiment for the present invention. Based on such understanding, the technical solutions of the present invention may be embodied in the form of a software product, which is stored in a readable storage medium, such as a floppy disk, a usb disk, a removable hard disk, a Read-Only Memory (ROM), a Random Access Memory (RAM), a magnetic disk or an optical disk of a computer, and includes instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute the methods according to the embodiments of the present invention.

Claims

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

a base station acquires a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) modN ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N);

the base station generates a synchronization signal sequence with the length of M according to the first root sequence index;

and the base station maps the synchronization signal sequence with the length of M on M subcarriers and sends the synchronization signal sequence.

2. The method of claim 1, wherein a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

3. The method of claim 1, wherein N is odd or prime.

4. The method of claim 1,

5. The method of claim 1, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

the base station generates a synchronization signal sequence with the length of M according to the first root sequence index, and the method comprises the following steps:

the base station is N according to the length₁And a first ZC sequence of length N₂The second ZC sequence of (1) generates the synchronization signal sequence, the N₁And said N₂Are both less than said M.

6. The method according to claim 1 or 5, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

the base station maps the synchronization signal sequence with the length of M on M subcarriers, and the method comprises the following steps:

the base station will have a length of N₁Is mapped to N of M sub-carriers₁On the sub-carriers, the length is N₂Is mapped to N of M subcarriers₂On subcarriers, the N₁And said N₂The sum is less than or equal to said M.

7. The method according to claim 1, wherein when N-61 and T-3, the set of T root sequence indices is any three of 20, 41, 15, and 46.

8. The method according to claim 1, wherein when N is 63 and T is 3, the set of T root sequence indexes is any three of 8, 55, 16, and 47.

9. The method according to claim 1, wherein when N is 127 and T is 3, the set of T root sequence indices is any three of 42, 85, 32, and 95.

10. The method of claim 1, wherein the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

11. The method of claim 1, wherein the base station obtains a first root sequence index from a set of T root sequence indexes, comprising:

and the base station acquires a first root sequence index from a set consisting of the T root sequence indexes according to the cell identification ID information.

12. A synchronization signal detection method, comprising:

the method comprises the steps that user equipment obtains a first root sequence index from a set consisting of T root sequence indexes, wherein T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the length of the ZC sequence is N, and any root sequence index u in the set consisting of the T root sequence indexes meets the following root selection condition: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N);

the user equipment generates a synchronization signal sequence with the length of M according to the first root sequence index;

and the user equipment processes the received signal by using the synchronization signal sequence with the length of M.

13. The method of claim 12, wherein a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

14. The method of claim 12, wherein N is odd or prime.

15. The method of claim 12,

16. The method of claim 12, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

the user equipment generates a synchronization signal sequence with the length of M according to the first root sequence index, and the method comprises the following steps:

the user equipment is N according to the length₁And a first ZC sequence of length N₂The second ZC sequence of (1) generates the synchronization signal sequence, the N₁And said N₂Are both less than said M.

17. The method according to claim 12 or 16, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

the user equipment processes the received signal by using the synchronization signal sequence with the length of M, and the method comprises the following steps:

n of M subcarriers for the user equipment₁On a subcarrier, and N out of M subcarriers₂And processing the received signal by using the synchronization signal sequence with the length of M on the sub-carrier.

18. The method according to claim 12, wherein when N-61 and T-3, the set of T root sequence indices is any three of 20, 41, 15, and 46.

19. The method according to claim 12, wherein when N is 63 and T is 3, the set of T root sequence indexes is any three of 8, 55, 16, and 47.

20. The method according to claim 12, wherein when N is 127 and T is 3, the set of T root sequence indices is any three of 42, 85, 32, and 95.

21. The method of claim 12, wherein the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

22. The method of claim 12, wherein the obtaining, by the ue, a first root sequence index from a set of T root sequence indexes comprises:

the user equipment obtains at least one root sequence index in a set formed by the T root sequence indexes as a first root sequence index.

23. The method of claim 12, wherein the ue processes the received signal using the length-M synchronization signal sequence, and comprises:

and the user equipment performs correlation operation by using the synchronization signal with the length of M and the received signal.

24. A base station, comprising:

a processing module, configured to obtain a first root sequence index from a set of T root sequence indexes, where T is a positive integer, the first root sequence index is a root sequence index of a ZC sequence, the ZC sequence has a length of N, and any root sequence index u in the set of T root sequence indexes satisfies a root selection condition as follows: (a × u) mod N ═ 1, or (a × u) mod N ═ N-1, where N is an integer greater than 1, u is an integer, a is an element in a subset of the root selection parameter set {3, 4, 5, 6, 7, 8}, and any two root sequence indices b, c in the set of T root sequence indices satisfy the following condition: b ≠ c (mod N);

the processing module is configured to generate a synchronization signal sequence with a length of M according to the first root sequence index;

the processing module is configured to map the synchronization signal sequence with the length of M onto M subcarriers;

a sending module, configured to send the synchronization signal sequence with the length M mapped on the M subcarriers by the processing module.

25. The base station of claim 24, wherein a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

26. The base station of claim 24, wherein N is odd or prime.

27. The base station of claim 24,

28. The base station of claim 24, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

29. The base station according to claim 24 or 28, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

30. The base station of claim 24, wherein when N is 61 and T is 3, the set of T root sequence indexes is any three of 20, 41, 15, and 46.

31. The base station of claim 24, wherein when N is 63 and T is 3, the set of T root sequence indexes is any three of 8, 55, 16, and 47.

32. The base station of claim 24, wherein when N is 127 and T is 3, the set of T root sequence indexes is any three of 42, 85, 32, and 95.

33. The base station of claim 24, wherein the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

34. The base station of claim 24, wherein the processing module is specifically configured to obtain a first root sequence index from a set of T root sequence indexes according to cell identification ID information.

35. A user device, comprising:

and the processing module is used for processing the received signal by using the synchronization signal sequence with the length of M.

36. The UE of claim 35, wherein a subset of the root selection parameter set {3, 4, 5, 6, 7, 8} is: {3, 4} or {3, 4, 6, 8 }.

37. The UE of claim 35, wherein N is odd or prime.

38. The user equipment of claim 35,

39. The UE of claim 35, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

40. The UE of claim 35 or 39, wherein the ZC sequence comprises: a first ZC sequence and a second ZC sequence;

41. The ue of claim 35, wherein when N is 61 and T is 3, the set of T root sequence indexes is any three of 20, 41, 15, and 46.

42. The ue of claim 35, wherein when N is 63 and T is 3, the set of T root sequence indexes is any three of 8, 55, 16, and 47.

43. The ue of claim 35, wherein when N is 127 and T is 3, the set of T root sequence indexes is any three of 42, 85, 32, and 95.

44. The UE of claim 35, wherein the synchronization signal sequence comprises: a primary synchronization signal sequence, or a secondary synchronization signal sequence.

45. The ue of claim 35, wherein the processing module is specifically configured to obtain at least one root sequence index in a set of T root sequence indexes as a first root sequence index.

46. The UE of claim 35, wherein the processing module is specifically configured to perform a correlation operation using the synchronization signal with length M and the received signal.