CN105122751B

CN105122751B - It is a kind of for synchronous signaling method and device

Info

Publication number: CN105122751B
Application number: CN201480000855.2A
Authority: CN
Inventors: 黎超
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-03-19
Filing date: 2014-03-19
Publication date: 2019-04-12
Anticipated expiration: 2034-03-19
Also published as: CN105122751A; WO2015139249A1

Abstract

It is a kind of for synchronous signaling method, comprising: utilize sequence b (n) generate be used for synchronization signal sequence d (n)；The sequence d (n) is mapped to corresponding resource location, generates synchronous baseband signal s；After carrying out radio frequency processing to the baseband signal s, send；Wherein, the length of the sequence d (n) for synchronization signal is not less than the length of the sequence b (n).The embodiment of the present invention is also disclosed a kind of for synchronous sender unit.Using the embodiment of the present invention, the communication performance of D2D communication system can be effectively improved.

Description

Signal sending method and device for synchronization

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a signal transmission method and apparatus for synchronization.

Background

Synchronization is a key technology for communication systems, especially wireless communication systems. Whether the receiver can synchronize efficiently to the transmitter will greatly affect the performance of the actual communication system.

Currently, 3GPP (The 3rd Generation Partnership Project) is implementing a communication system named D2D (Device to Device to Device), i.e. multiple UEs (user equipment) can directly perform inter-Device communication, and The data to be communicated does not need to pass through The base station for relaying.

Referring to fig. 1, a scene diagram of a typical D2D system is shown. As shown in fig. 1, a base station of LTE (Long term evolution) transmits a Primary Synchronization Signal to a serving UE therebelow through PSS (Primary Synchronization Signal).

The UE in the cellular link receives the PSS from the LTE base station, the receiver detects and processes the received PSS to obtain time synchronization and frequency synchronization with the base station, and then the UE starts to receive data from the base station to realize subsequent communication.

The UE on the D2D link, whose transmitter transmits a PD2DSS (Primary D2D synchronizing signal, Primary D2D synchronization signal), so that the receiver of the UE on the D2D link can synchronize to the transmitter of D2D based on the received PD2DSS to receive data from the D2D transmitter.

In fig. 1, D2D communication may be either within the range of cellular coverage (as shown by UE1 and UE2 in fig. 1) or outside the range of cellular coverage (as shown by UE3 and UE4 in fig. 1). In addition, the same UE may perform cellular communication or D2D communication (as shown by UE5 in fig. 1). Specifically, which communication is performed is not divided by the UE, but by the link on which the UE is located. I.e., a UE on a cellular link or a UE on a D2D link, and for the same UE, the transition between the two links is handled in a TDD (Time Division Duplex) manner.

In the prior art, PSS is generally adopted directly as PD2DSS used in D2D system. However, as shown in fig. 1, in the TDD mode, the D2D system may use either an uplink subframe or a downlink subframe. While using the downlink subframe, if the PD2DSS is the same as the PSS, this will cause the receiver of the UE of the D2D link to erroneously detect the downlink PSS of the LTE cell as PD2 DSS. Likewise, the receiver of the UE of the cellular link may also erroneously detect as PSS the PD2DSS transmitted by the UE of the D2D link.

Therefore, in the prior art, the PD2DSS and the PSS are the same, which may cause signal detection errors in the D2D system, thereby reducing the communication performance of the communication system.

Disclosure of Invention

Embodiments of the present invention provide a signal sending method and apparatus for synchronization, which can effectively improve communication performance of a D2D communication system.

In a first aspect, a signaling apparatus for synchronization is disclosed, the apparatus comprising:

a first generation unit configured to generate a sequence d (n) for a synchronization signal using the sequence b (n); wherein the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n);

a second generating unit, configured to map the sequence d (n) to a corresponding resource location, and generate a synchronized baseband signal s;

the radio frequency processing unit is used for carrying out radio frequency processing on the baseband signal s;

and the transmitting unit is used for transmitting the signals processed by the radio frequency processing unit.

In a first possible implementation manner of the first aspect, the sequence b (n) is:

the original value of the perfect sequence;

or,

the perfect sequence is generated after Discrete Fourier Transform (DFT);

or,

the perfect sequence is subjected to Inverse Discrete Fourier Transform (IDFT) to generate a sequence;

wherein the perfect sequence is a ZC sequence or a GCL sequence.

With reference to the first aspect and the first possible implementation manner of the first aspect, in a second possible implementation manner of the first aspect, the first generating unit generates the sequence d (n) by using the following formula:

wherein L is an odd number.

With reference to the second possible implementation manner of the first aspect, in a third possible implementation manner of the first aspect, the sequence b (n) is:

wherein:orj is an imaginary unit; u is the root sequence number of the sequence b (n); the u and the L are prime numbers.

With reference to the third possible implementation manner of the first aspect, in a fourth possible implementation manner of the first aspect, the sequence d (n) generated by the first generating unit is:

wherein u is the root sequence number of the sequence d (n).

With reference to the third possible implementation manner of the first aspect, in a fifth possible implementation manner of the first aspect, the sequence d (n) generated by the first generating unit is:

wherein u is the root sequence number of the sequence d (n).

With reference to the first aspect and any one of the foregoing possible implementation manners of the first aspect, in a sixth possible implementation manner of the first aspect, the second generating unit includes:

a first mapping subunit, configured to continuously map sequences d (0) to d ((L-1)/2) to one side of a subcarrier with an index k, and continuously map sequences d ((L +1)/2) to d (L) to the other side of the subcarrier with the index k; and the data on the subcarrier with the index of k is 0.

With reference to the sixth possible implementation manner of the first aspect, in a seventh possible implementation manner of the first aspect, the second generating unit further includes:

and the first baseband signal generating subunit is configured to generate the synchronized baseband signal s by using an orthogonal frequency division multiplexing, OFDM, method.

With reference to the seventh possible implementation manner of the first aspect, in an eighth possible implementation manner of the first aspect, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

wherein v ═ L-u, u and v are the root sequence numbers of s (n), and s is_u(n) and s_v(n) is s (n) an expression using root sequence numbers u and v.

With reference to the first aspect and any one of the foregoing possible implementation manners of the first aspect, in an eighth possible implementation manner of the first aspect, the second generating unit includes:

and a second mapping subunit, configured to map the sequences d (0) to d (L) onto L +1 consecutive equally-spaced frequency-domain subcarriers.

With reference to the ninth possible implementation manner of the first aspect, in a tenth possible implementation manner of the first aspect, the second generating unit further includes:

and the second baseband signal generating subunit is used for generating the synchronous baseband signal s by adopting a single carrier frequency division multiple access (SC-FDMA) method.

With reference to the tenth possible implementation manner of the first aspect, in an eleventh possible implementation manner of the first aspect, a sampling signal s (n) of the baseband signal s has an anti-centrosymmetry property and an anti-conjugate equality property; respectively as follows:

s(n)＝-s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

In a twelfth possible implementation manner of the first aspect, the generating, by the first generating unit, the sequence d (n) by using the following formula includes:

d(n)＝b(n),n＝0,1,...,L-1

wherein L is an even number.

With reference to the twelfth possible implementation manner of the first aspect, in a thirteenth possible implementation manner of the first aspect, the sequence b (n) is:

wherein,orj is an imaginary unit; u is the root sequence number of the sequence b (n); the u and the L are prime numbers.

With reference to the thirteenth possible implementation manner of the first aspect, in a fourteenth possible implementation manner of the first aspect, the second generating unit includes:

and a third mapping subunit, configured to map the sequences d (0) to d (L-1) onto L consecutive equally-spaced frequency-domain subcarriers.

With reference to the fourteenth possible implementation manner of the first aspect, in a fifteenth possible implementation manner of the first aspect, the second generating unit further includes:

and the third baseband signal generating subunit is used for generating the synchronous baseband signal s by adopting a single carrier frequency division multiple access (SC-FDMA) method.

With reference to the fifteenth possible implementation manner of the first aspect, in a sixteenth possible implementation manner of the first aspect, the second generating unit further includes:

and the fourth baseband signal generating subunit is used for sequentially arranging and placing the chips of the sequence d (n) in the synchronization signal of the time domain.

With reference to the sixteenth possible implementation manner of the first aspect, in a seventeenth possible implementation manner of the first aspect, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

wherein v is 2m L-u, m being an integer; u and v are the root sequence number of s (n), s_u(n) and s_v(n) is an expression using root sequence numbers u and v for s (n).

In a second aspect, a signaling method for synchronization is disclosed, the method comprising:

generating a sequence d (n) for a synchronization signal using the sequence b (n);

mapping the sequence d (n) to a corresponding resource position to generate a synchronous baseband signal s;

carrying out radio frequency processing on the baseband signal s and then sending out the baseband signal s;

wherein the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n).

In a first possible implementation manner of the second aspect, the sequence b (n) is:

the original value of the perfect sequence;

or,

the perfect sequence is generated after Discrete Fourier Transform (DFT);

or,

wherein the perfect sequence is a ZC sequence or a GCL sequence.

With reference to the second aspect and the first possible implementation manner of the first aspect, in a second possible implementation manner of the second aspect, the generating a sequence d (n) for a synchronization signal by using the sequence b (n) includes:

wherein L is an odd number.

With reference to the second possible implementation manner of the second aspect, in a third possible implementation manner of the second aspect, the sequence b (n) is:

With reference to the third possible implementation manner of the second aspect, in a fourth possible implementation manner of the second aspect, the sequence d (n) is:

wherein u is the root sequence number of the sequence d (n).

With reference to the third possible implementation manner of the second aspect, in a fifth possible implementation manner of the second aspect, the sequence d (n) is:

wherein u is the root sequence number of the sequence d (n).

With reference to the second aspect and any one of the foregoing possible implementations of the first aspect, in a sixth possible implementation of the second aspect, the mapping the sequence d (n) to a corresponding resource location includes:

the data on the subcarrier with the index of k is 0;

the sequences d (0) to d ((L-1)/2) are consecutively mapped to one side of the subcarrier with index k, and the sequences d ((L +1)/2) to d (L) are consecutively mapped to the other side of the subcarrier with index k.

With reference to the sixth possible implementation manner of the second aspect, in a seventh possible implementation manner of the second aspect, the synchronized baseband signal s is generated by using an orthogonal frequency division multiplexing, OFDM, method.

With reference to the seventh possible implementation manner of the second aspect, in an eighth possible implementation manner of the second aspect, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

With reference to the second aspect and any one of the foregoing possible implementations of the first aspect, in an eighth possible implementation of the second aspect, the mapping the sequence d (n) to a corresponding resource location includes:

the sequences d (0) to d (L) are mapped onto L +1 consecutive equally spaced frequency domain subcarriers.

With reference to the ninth possible implementation manner of the second aspect, in a tenth possible implementation manner of the second aspect, the synchronized baseband signal s is generated by a single carrier frequency division multiple access SC-FDMA method.

With reference to the tenth possible implementation manner of the second aspect, in an eleventh possible implementation manner of the second aspect, a sampling signal s (n) of the baseband signal s has an anti-centrosymmetry and an anti-conjugate equality; respectively as follows:

s(n)＝-s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

In a twelfth possible implementation manner of the second aspect, the generating a sequence d (n) for a synchronization signal by using the sequence b (n) includes:

d(n)＝b(n),n＝0,1,...,L-1

wherein L is an even number.

With reference to the twelfth possible implementation manner of the second aspect, in a thirteenth possible implementation manner of the second aspect, the sequence b (n) is:

With reference to the thirteenth possible implementation manner of the second aspect, in a fourteenth possible implementation manner of the second aspect, the mapping the sequence d (n) to a corresponding resource location includes:

sequences d (0) to d (L-1) are mapped onto L consecutive equally spaced frequency domain subcarriers.

With reference to the fourteenth possible implementation manner of the second aspect, in a fifteenth possible implementation manner of the second aspect, the synchronized baseband signal s is generated by a single carrier frequency division multiple access SC-FDMA method.

With reference to the fifteenth possible implementation manner of the second aspect, in a sixteenth possible implementation manner of the second aspect, the generating the synchronized baseband signal s includes:

and sequentially arranging the chips of the sequence d (n) in a synchronization signal of a time domain.

With reference to the sixteenth possible implementation manner of the second aspect, in a seventeenth possible implementation manner of the second aspect, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

wherein v is 2m L-u, m being an integer; u and v are the root sequence number of s (n), s_u(n) and s_v(n) is s (n) an expression using root sequence numbers u and v

In the method and apparatus according to the embodiment of the present invention, the sequence d (n) for the synchronization signal is generated by using the sequence b (n), and the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n). While typical PSS are generated from odd sequences of length L to even sequences of length L-1.

Therefore, the synchronization signal used for the D2D obtained in the embodiment of the present invention is different from the PSS, so that the problem of a signal detection error of the D2D system caused by the fact that the synchronization signal of the D2D is the same as the PSS is avoided, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic diagram of a typical D2D system;

fig. 2 is a flowchart of a signal transmission method for synchronization according to a first embodiment of the present invention;

FIG. 3 is a diagram illustrating the sequence d (n) mapped by frequency domain according to the second embodiment of the present invention;

fig. 4 is a schematic diagram of time domain synchronization signal transmitter mapping according to a third embodiment of the present invention;

FIG. 5 is a diagram illustrating the sequence d (n) mapped by frequency domain according to the third embodiment of the present invention;

FIG. 6 is another diagram illustrating the sequence d (n) mapped by frequency domain according to the third embodiment of the present invention;

FIG. 7 is a block diagram of an exemplary receiver;

fig. 8 is a block diagram of a signal transmitting apparatus for synchronization according to an embodiment of the present invention.

Detailed Description

In order to make the technical solutions in the embodiments of the present invention better understood and make the above objects, features and advantages of the embodiments of the present invention more comprehensible, the technical solutions in the embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

Embodiments of the present invention provide a method and an apparatus for sending a synchronization signal, which can effectively improve communication performance of a D2D communication system.

The method and the device of the embodiment of the invention have the core thought that: to a new sequence for generating a synchronization signal of D2D such that the synchronization signal is different from the PSS and the generated synchronization signal is used with good correlation and symmetry. Therefore, on the premise of not influencing the detection performance and not improving the detection complexity, the problem of signal detection error of the D2D system caused by the fact that the synchronization signal of the D2D is the same as the PSS can be solved, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

Fig. 2 is a flowchart of a signal transmission method for synchronization according to a first embodiment of the present invention. As shown in fig. 2, the method comprises the steps of:

step S101: generating a sequence d (n) for a synchronization signal using the sequence b (n); wherein the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n).

Step S102: mapping the sequence d (n) to a corresponding resource position to generate a synchronous baseband signal s;

step S103: and after the baseband signal s is subjected to radio frequency processing, sending out the baseband signal s.

In the method according to the embodiment of the present invention, the sequence d (n) for the synchronization signal is generated by using the sequence b (n), and the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n). While typical PSS are generated from odd sequences of length L to even sequences of length L-1. Therefore, the synchronization signal of the D2D obtained by the embodiment of the invention is different from the PSS, the problem of signal detection error of the D2D system caused by the fact that the synchronization signal of the D2D is the same as the PSS is solved, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

The following describes a signal transmission method for synchronization according to an embodiment of the present invention in detail with reference to specific embodiments.

Example two:

in the method according to the second embodiment of the present invention, the length of the generated sequence for the synchronization signal is odd, and the method can be directly applied to a time domain scene or a frequency domain scene using multi-carrier modulation.

Specifically, in the second embodiment, the generating sequence d (n) by using the sequence b (n) is specifically:

wherein, b (n), n ═ 0, 1., L-1; l is an odd number.

Thus, b (n) is an odd sequence of length L, and an even sequence d (n) of length (L +1) is generated using sequence b (n). The length of the sequence d (n) is larger than that of the sequence b (n).

In the prior art, the PSS is an even sequence with a length of L-1 generated by an odd sequence with a length of L, so that the finally obtained synchronization signal is different from the PSS.

Further, the sequence b (n) may be a perfect sequence. The perfect sequence refers to a sequence having ideal periodic autocorrelation function values. Specifically, the perfect sequence satisfies the following formula (2):

wherein mod is a modulo function, | b (n) non-volatile memory²Expressed as the arithmetic square of the absolute value of b (n).

It should be noted that, in the method according to the embodiment of the present invention, the perfect sequence b (n) may specifically be: a ZC (Zadoff-Chu) sequence or a GCL sequence.

Wherein, the ZC sequence and the GCL sequence both have very good autocorrelation and very low cross correlation, and the performance can be used for generating a synchronization signal, so that a receiver can realize the synchronization detection of time and frequency according to the received synchronization signal. Specifically, when a ZC sequence is used as the sequence b (n), the sequence b (n) can be expressed as:

wherein:orj is an imaginary unit; u is a root sequence number of the ZC sequence.

Specifically, when a GCL sequence is used as the sequence b (n), the sequence b (n) can be represented by:

b(n)＝c(n)*g((n)mod m),n＝0,1,...,L-1 (4)

wherein L is s m²(ii) a c (n) is a perfect sequence; g (n), where n is 0,1, and m-1 is a complex number of 1 for each element of length m, i.e.: 1, | g (n) | 1, n ═ 0, 1. An example of a sequence g (n) may be: any row or column in a Hadamard (Hadamard) matrix of length m.

It should be further noted that, in the embodiment of the present invention, the sequence b (n) may be an original value (shown in equations 3 and 4) of a perfect sequence (e.g., a ZC sequence or a GCL sequence), or may be a value obtained by performing DFT (Discrete Fourier Transform) or IDFT (Inverse Discrete Fourier Transform) on the perfect sequence.

Specifically, the following description will take ZC sequence as an example.

When the value of the ZC sequence after DFT is used as the sequence b (n), the sequence b (n) may be represented as:

when a value obtained by IDFT of a ZC sequence is used as the sequence b (n), the sequence b (n) can be expressed as:

wherein b in the formulae (5) and (6)_t(m) is the original value of the ZC sequence.

Several cases in which the sequence b (n) can be used are described above. It should be emphasized that, in practical applications, the perfect sequence is not limited to ZC sequence and GCL sequence, and in fact, any perfect sequence satisfying equation (2) can be used for the sequence b (n) described in the embodiments of the present invention to achieve the object of the present invention, and will not be described herein again.

Still taking ZC sequence as an example, when ZC sequence is used as sequence b (n), sequence d (n) for synchronization signal generated in the embodiment of the present invention can be specifically expressed as:

or,

in the second embodiment, L is an odd number, the length of the sequence d (n) is L +1, u is the root sequence number of the sequence d (n), and n represents chips at different positions of the sequence. Wherein, the above formulas (7) and (8) are sequences d (n) that can be used to generate the method of the embodiment of the present invention.

It should be further noted that the sequence d (n) (for example, shown in formula 7 or formula 8) obtained in the embodiment of the present invention has central symmetry, that is, the sequence d (n) satisfies:

d(n)＝d(L-n),n＝0,1,...,L (9)

and, the sequence d (n) also satisfies the conjugate equality:

where, when v is L-u, u and v are the root sequence numbers of the sequence d (n), and d_u(n) and d_v(n) is d (n) an expression using root sequence numbers u and v.

In practical application, the value of L in the sequence d (n) can be specifically set according to actual needs. In a preferred embodiment, L may be 61.

Specifically, when L is 61, the specific expression of the corresponding sequence d (n) with the length of 62 is as follows:

or,

it should be noted that the length of the synchronization signal is limited. In the LTE system, the PSS is a bandwidth of 6 PRBs occupying the most center of a bandwidth of one OFDM (Orthogonal Frequency Division Multiplexing) symbol. In an LTE system, one PRB occupies 12 subcarriers in the frequency domain, each subcarrier being 15 kHz.

Therefore, the PSS signal occupies 6 × 12 × 15 ═ 1.08 MHz. That is, in the LTE system, the PSS signal occupies no more than 72 subcarriers in the frequency domain. Meanwhile, considering that 5 subcarriers are required to be left on both sides of the frequency domain of the PSS signal, the length of the PSS signal is generally 62. The length of the similar synchronization signal will not exceed 72, and considering the number of guard sub-carriers and the complexity of the receiver, the preferred length will not exceed 64 sub-carriers, which leave 4 sub-carriers on both sides.

For the sequence d (n) for the synchronization signal generated in the second embodiment of the present invention, mapping the sequence d (n) to the corresponding resource location specifically includes: referring to fig. 3, a schematic diagram of mapping the sequence d (n) using frequency domain according to the second embodiment of the present invention is shown. In fig. 3, a frequency domain sequence d (n) with a length of 62 is placed on 72 subcarriers in total of 6 PRBs in the LTE system.

As shown in FIG. 3, the sequence d (n) having a length of 62 is described as an example. It should be noted that, in fig. 3, for an unused carrier, the data mapped to the unused carrier is 0.

Specifically, the method for mapping the sequence d (n) with the length of L +1 to the frequency domain includes:

no chip of the sequence is mapped on the subcarrier with index k, on which the data is 0.

D (0), d ((L-1)/2) are mapped consecutively to consecutive equally spaced subcarriers located on one side (typically the left side) of the subcarrier with index k. D ((L +1)/2),. -, d (L) are successively mapped onto successive equally spaced subcarriers located on the other side (typically the right side) of the subcarrier with index k. Subcarrier k may be a DC subcarrier. It should be noted that the DC subcarrier is for the receiver, i.e. the position corresponding to the center frequency of the receiver, and at the transmitter it corresponds to the center subcarrier of the transmitter on the system bandwidth. In the present embodiment, DC subcarrier is simply referred to.

In general, the k-indexed subcarrier may be a DC subcarrier. Specifically, the d (n) and the data a on each subcarrier mapped on the carrier frequency by the baseband signal_kThe mapping relationship between the two is as follows:

a_k＝d(n),n＝0,1,...,L (13)

wherein k is N- (L +1)/2+ N/2;

wherein the parameter N value is used for the downlink OFDM modulation of LTEWhereinThe number of RBs configured in the downlink bandwidth,the size of the resource block in the frequency domain is 12 in the LTE protocol, and the maximum value of N is the number of points of the IDFT corresponding to the frequency domain bandwidth occupied by the time domain signal, for example, N is 2048 for 20MHz bandwidth.

At this time, d (0),.. d,. d ((L-1)/2) is continuously mapped to subcarriers having relative indexes of- (L +1)/2, …, -1 located at the left side of the DC subcarrier. D ((L +1)/2),. -, d (L) are consecutively mapped onto subcarriers with relative indices 1, …, (L +1)/2 located to the right of the DC subcarrier.

With reference to fig. 3, the description will be given taking L61 as an example, and for a sequence d (n) having a length of 62: d (0), d (30) is mapped consecutively to subcarriers with relative indices-31, …, -1 located to the left of the DC subcarrier. D (31), d (61) is mapped successively to subcarriers with relative indices 1, …,31 located to the right of the DC subcarrier; the data on the DC subcarrier is 0. Specifically, at this time, the d (n) and the data a on each subcarrier mapped on the carrier frequency by the baseband signal are_kThe mapping relationship between the two is as follows:

a_k＝d(n),n＝0,1,...,61 (14)

wherein k is N-31+ N/2

In the second embodiment of the present invention, after the frequency domain mapping of the sequence d (n) is completed according to the above method, the obtained frequency domain signal is subjected to OFDM transform or IDFT transform, the frequency domain signal is converted into a time domain signal, a synchronous baseband signal s is generated, and the baseband signal s is subjected to radio frequency processing and then transmitted.

Specifically, the radio frequency processing may be processing such as up-conversion and filtering on a baseband signal.

Thereby, the signal transmission method for synchronization according to the second embodiment of the present invention is implemented.

The method for generating the baseband signal s in the second embodiment of the present invention is completely the same as the method for generating the downlink baseband signal in the LTE system. And will not be described in detail herein.

The time domain signal generated by OFDM-transforming the frequency domain signal will be briefly described below. Specifically, in the second embodiment of the present invention, the expression of the time domain signal may be:

wherein t represents the time argument of the time domain signal s (t);

Δ f is the subcarrier spacing, which in an LTE system may be 15kHz or 7.5 kHz;

a_kthe values are corresponding values after the frequency domain data are mapped to corresponding carriers, and comprise the values after the synchronous sequence is mapped;

wherein, for downlink OFDM modulation of LTEWhereinThe number of RBs configured in the downlink bandwidth,the size of the resource block in the frequency domain is 12 in the LTE protocol, and the maximum value of N is the number of points of the IDFT corresponding to the frequency domain bandwidth occupied by the time domain signal, for example, N is 2048 for 20MHz bandwidth.

The root sequence generated by the above equation (15) is a sampling signal s (n) of the u baseband signal s, which may be denoted as s for convenience_u(N), N ═ 0,1, 2.., N-1, the sampling signal s_u(n) may include both synchronization signals and data signals on other carriers.

The following are specifically mentioned: because the sequence d (n) generated in the embodiment of the present invention has central symmetry (shown in formula 9) and conjugate equivalence (shown in formula 10), and the mapping method shown in fig. 3 is adopted, the sampling signal s (n) that only includes the baseband signal s generated in this embodiment also has central symmetry and conjugate correlation characteristics.

Specifically, the sampling signal s (n) of the baseband signal s has central symmetry:

s(n)＝s(N-n),n＝1,2,...,N-1 (16)

when v-L-u, the sequence has the property of conjugate equality:

denotes s_v(n) complex conjugate operation of (n). After the receiver receives the signal synchronization signal, the baseband acquisition is obtained through samplingAnd (2) a sample signal r (n), wherein r (n) has the symmetrical characteristics of the above equations (14) and (15), and the receiver can perform simplified operation of receiving matched filtering according to the characteristics of the above equations (16) and (17).

Further, taking the conventional typical PSS sequence with a length of 62 as an example, the PSS sequence is generated from a ZC sequence with a length of 63, but in the embodiment of the present invention, the sequence d (n) may be generated using a ZC sequence with a length of 61. When choosing a ZC sequence, its root sequence number u must be prime to the length L of the ZC sequence. Then, in the prior art, for a ZC sequence of length 63, the set of root sequence numbers that can be selected is: {1,2,4,5,8,10,11,13,16,17,19,20,21,22,23,25,26,29,31,32,34,37,38,40,41,43,44,46,47,49,50,53,55,58,59,61,62}, a total of 37 sequences.

And, in order to ensure cross-correlation between sequences, the difference between the root sequence numbers of any two sequences must be relatively prime to the sequence length L. The 3 sequences of PSS in LTE are still examples. The root sequence numbers of the 3 sequences of PSS are 25, 29, 34, respectively, and the difference between the root sequence numbers of 25 and 34 is 9, 9 and 63 are not in a reciprocal relationship, so that the cross-correlation between the two sequences of 25 and 34 is poor in practice.

For the sequence with the length of 61 described in the second embodiment of the present invention, because 61 itself is a prime number, if the sequences with the root sequence numbers u of 25, 29 and 34 are still used, the difference between the root sequence numbers of any two sequences and the sequence length 61 are all prime, so that the correlation between multiple sequences is ensured. And because 61 is a prime number, 60 sequences with different root sequence number u values can be generated in total, and the correlation between the sequences can be guaranteed no matter which of the 60 sequences is adopted to generate different synchronous signals.

It can be seen that the method of the present embodiment provides a new option for selecting a sequence during generation of a sync signal of a specific length, and has obvious advantages in a design process similar to that for a sync signal of length 62.

Therefore, if the transmitter transmits the synchronization signal by using the method provided by the second embodiment of the present invention, when more than 1 synchronization signal needs to be transmitted, the sequence can be generated in a v-L-u pair-wise manner as much as possible.

As can be seen from the above description, in the method according to the second embodiment of the present invention, the perfect sequence b (n) is used to generate the sequence d (n) for the synchronization signal, and the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n). Therefore, the synchronization signal obtained by the embodiment of the invention is different from the PSS, the problem of D2D system signal detection error caused by the fact that the synchronization signal is the same as the PSS is solved, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

Meanwhile, in the second embodiment of the present invention, a perfect sequence (e.g., ZC sequence or GCL sequence) of odd length long by L is used to generate a sequence of even length long by L + 1. Compared with the existing method for generating the even-numbered sequence with the length of L-1 from the odd-numbered sequence with the length of L, the method for selecting the parameters is added to the sequence generated in the second embodiment of the invention.

Furthermore, the method of the second embodiment of the invention has obvious advantages under certain parameters. For example, when a length-62 sequence is to be generated, a related art method is to generate using a length-63 ZC sequence. And 63 is a non-prime integer, so the correlation performance and the parameter selection of the root sequence number of the generated sequence are greatly limited. By adopting the method of the second embodiment of the present invention, the ZC sequence with the length of 61 can be used to generate the sequence with the length of 62, and since 61 is a prime number, there is no limitation on the root number of the generated sequence, and the correlation performance is better.

Example three:

in the method according to the third embodiment of the present invention, the length of the generated sequence for the synchronization signal is an even number, and the method can be directly applied to a time domain scene or a Frequency domain SC-FDMA (Single-carrier Frequency-Division Multiple Access) modulation scene without a DC carrier.

Specifically, in the third embodiment, the generating sequence d (n) by using the sequence b (n) is specifically:

d(n)＝b(n),n＝0,1,...,L-1 (18)

wherein L is an even number.

In the third embodiment of the present invention, the length of the sequence b (n) and the length of the sequence d (n) are both L.

Further, the sequence b (n) may be a perfect sequence. The perfect sequence is the same as described in example two. In particular, the perfect sequence b (n) may be specifically: a ZC sequence or a GCL sequence.

Specifically, when a ZC sequence is used as the sequence b (n), the sequence b (n) can be expressed as:

wherein:orL is the length of the sequence; u is the root sequence number of the sequence; the u and the L are prime numbers.

It should be further noted that, in the third embodiment of the present invention, the sequence b (n) may be an original value of a perfect sequence (e.g., ZC sequence or GCL sequence), or may be a DFT or IDFT value of the perfect sequence.

Specifically, the following description will take ZC sequence as an example.

wherein b in the formulae (20) and (21)_t(m) is the original value of the ZC sequence.

In the third embodiment of the present invention, L is an even number, the length of the generated sequence d (n) is L, u is the root sequence number of the sequence d (n), which is required to be relatively prime to the sequence length L, further, when u is a prime number, the correlation performance of the sequence is more guaranteed, and n represents chips at different positions of the sequence.

It should be further noted that the sequence d (n) obtained in the embodiment of the present invention has central symmetry, that is, the sequence d (n) satisfies:

d(n)＝d(L-n),n＝1,...,L-1 (22)

and, the sequence d (n) also satisfies the conjugate equality:

wherein u + v is 2mL, m ∈ Z, u and v are root sequence numbers of the sequence d (n), and d_u(n) and d_v(n) is d (n)Expressions for root sequence numbers u and v are used.

If m is 0 or m is 1, there are: v-u, v-2L-u.

In practical application, the value of L in the sequence d (n) can be specifically set according to actual needs. In a preferred embodiment, L may be 64 or 62.

Specifically, when L is 64, the specific expression of the corresponding sequence d (n) with the length of 64 is as follows:

or,

specifically, when L is 62, the specific expression of the corresponding sequence d (n) with the length of 62 is as follows:

or,

it should be noted that the method described in the third embodiment of the present invention may be used in a time domain and also in a frequency domain scenario without a DC carrier.

(1) Third, the method of the embodiment of the invention is applied to a time domain modulation scene

Fig. 4 is a schematic diagram of time domain synchronization signal transmitter mapping in the third embodiment of the present invention. When the method is used in a time domain scenario, as shown in fig. 4, at least one synchronization signal is placed in a certain frame or sub-frame of the baseband signal for the transmitter side. Specifically, the frame or the subframe is only a time length for placing data, and the synchronization signal is placed at a position of the time length. In the synchronization signal, the chips of the sequence d (n) generated in the third embodiment of the present invention are arranged in sequence as shown in fig. 4.

When the method is used in a time domain scenario, the base-band signal s of the synchronization signal generated by the ZC sequence with the root sequence u may be denoted as s again for convenience of notation_u(N), N ═ 0,1, 2.., N-1. On the receiving side, the equivalent sampling signal s (n) of the baseband signal s in the receiver also has central symmetry, i.e.:

s(n)＝s(N-n),n＝1,...,N-1 (28)

wherein N is the number of sampling points.

And when v is 2mL-u, m ∈ Z, the sequence s_u(n) and the sequence s_v(n) has conjugate equality property:

when m is 0, v is-u, and when m is 1, v is 2L-u.

(2) Third, the method of the embodiment of the invention is applied to SC-FDMA modulation scenes

For the sequence d (n) for PD2DSS generated in the third embodiment of the present invention, mapping the sequence d (n) to a corresponding resource location specifically includes: fig. 5 and fig. 6 are a schematic diagram and another schematic diagram of mapping the sequence d (n) using frequency domain according to a third embodiment of the present invention. In fig. 5 and 6, a frequency domain sequence d (n) with a length of 64 is placed on 72 subcarriers in total of 6 PRBs in an LTE system as an example for explanation

As shown in FIG. 5, the sequence d (n) having a length of 64 will be described as an example. In the third embodiment of the present invention, the sequence d (n) is mapped onto L consecutive equally spaced frequency domain subcarriers from d (0) to d (L-1). The L consecutive equally spaced frequency domain subcarriers may include a DC subcarrier, or may not include a DC subcarrier.

Specifically, if the L consecutive equally spaced frequency domain subcarriers include a DC subcarrier, as shown in fig. 5, a chip d (L/2) of a sequence d (n) is mapped on the DC subcarrier.

If the DC subcarrier is not included in the L consecutive non-spaced frequency domain subcarriers, as shown in fig. 6.

In the third embodiment of the present invention, after the frequency domain mapping of the sequence d (n) is completed according to the above method, SC-FDMA conversion is performed on the obtained frequency domain signal, the frequency domain signal is converted into a time domain signal, and a synchronous baseband signal s (n) is generated and sent out.

Therefore, the method for transmitting the signal for synchronization according to the third embodiment of the present invention is implemented.

The generation method of the SC-FDMA baseband signal s (n) in the third embodiment of the invention is completely the same as the generation method of the uplink SC-FDMA baseband signal in the LTE system. And will not be described in detail herein.

Specifically, in the third embodiment of the present invention, the expression of the SC-FDMA baseband signal may be:

where Δ f is the subcarrier spacing, which in an LTE system may be 15kHz or 7.5kHz, where t represents the time argument of the time domain signal s (t);

ak is a corresponding value after mapping the frequency domain data to a corresponding carrier, and comprises a value after mapping a synchronization sequence;

for uplink SC-FDMA modulation of LTEWhereinIndicates the number of RBs configured in the uplink bandwidth,the size of the resource block in the frequency domain is 12 in the LTE protocol, and the maximum value of N is the number of points of the IDFT corresponding to the frequency domain bandwidth occupied by the time domain signal, for example, N is 2048 for 20MHz bandwidth.

The method of the third embodiment of the invention is suitable for signal transmission based on an LTE uplink SC-FDMA modulation mode. In the study of D2D, a modulation scheme using SC-FDMA is required for uplink transmission in both FDD (Frequency Division duplex) and TDD (time Division duplex). Therefore, if the UE in the D2D system transmits the synchronization signal according to the third embodiment, the system will be simpler, and the advantage of low peak-to-average ratio can be obtained.

Here, the basic structure and operation principle of the receiver of the UE will be briefly described. Referring to fig. 7, a block diagram of a typical receiver is shown. Of course, in practical applications, the mechanism of the receiver is not limited to that shown in fig. 7, and the embodiment of the present invention is only a brief description of the operation process of the receiver by taking the structure shown in fig. 7 as an example.

As shown in fig. 7, a receiver of the UE receives r (t) including a synchronization signal from a transmitter at an antenna 701, and transmits the r (t) to an RF (Radio Frequency) module 702 of the receiver for processing, wherein the RF module 702 includes a series of filtering down-conversion processes, and the purpose of the filtering down-conversion processes is to limit the signal within a certain bandwidth, so that an ADC (Analog to Digital Converter) 703 can perform efficient sampling. The quantized data output by the ADC 703 is then processed by down-conversion (down-converter 704) for the purpose of converting the signal to a baseband signal. The signal output by the down converter 704 is passed through a low pass filter 705 to obtain the desired baseband signal r (n).

When synchronization is required, it is necessary to filter out at least the signal on the bandwidth where the synchronization signal is located, so that the receiver can perform detection of the synchronization signal. Particularly, when the modulation scheme of SC-FDMA is used, the receiver needs to remove 1/2 offset values of the carrier before the baseband signal, and then perform baseband processing on the obtained baseband signal. The process of de-1/2 carrier can be implemented in the RF module 702 or the down converter 704. The method is realized by that the receiver removes 1/2 carrier frequency offset value during frequency conversion.

For the received signal ru (n) with 1/2 carrier offset removed, it has central symmetry, that is:

r_u(n)＝r_u(N-n),n＝1,...,N-1 (31)

when v is 2mL-u, and m is Z, r is_u(n) and r_v(n) conjugate equality:

example four:

in the fourth embodiment of the present invention, the method for generating the sequence d (n) is the same as that of the first embodiment of the present invention, and the odd-numbered sequence b (n) with the length L is used to generate the even-numbered sequence d (n) with the length (L + 1). Only brief introduction is given below, and the specific generation process is the same as that described in embodiment two, and is not described again.

Specifically, in the fourth embodiment, the generating sequence d (n) by using the sequence b (n) is specifically:

wherein, b (n), n ═ 0, 1., L-1; l is an odd number.

Thus, b (n) is a sequence of length L, and d (n) of length (L +1) is generated using the sequence b (n). The length of the sequence d (n) is larger than that of the sequence b (n).

Therefore, the finally obtained synchronization signal of the embodiment of the invention is different from the PSS.

In the method according to the fourth embodiment of the present invention, the perfect sequence b (n) may specifically be: a ZC sequence or a GCL sequence.

When a ZC sequence is employed as the sequence b (n), the sequence b (n) can be expressed as:

When a ZC sequence is used as the sequence b (n), the sequence d (n) for the synchronization signal generated in the embodiment of the present invention may be specifically represented as:

or,

in the fourth embodiment, L is an odd number, the length of the sequence d (n) is L +1, u is the root sequence number of the sequence d (n), and n represents chips at different positions of the sequence. Wherein, the above formulas (7) and (8) are sequences d (n) that can be used to generate the method of the embodiment of the present invention.

It should be further noted that, in the embodiment of the present invention, the sequence d (n) with the root sequence number u generated by using the ZC sequence (for example, as shown in formula 7 or formula 8) has central symmetry, that is, the sequence d (n) satisfies, for convenience of description, where d (n) is expressed by du (n):

d(n)＝d(L-n),n＝0,1,...,L (9)

and, the sequence d (n) also satisfies the conjugate equality:

The difference from the second embodiment of the present invention is that, in the fourth embodiment of the present invention, the frequency domain mapping method and the SC-FDMA modulation method described in the third embodiment are adopted for the generated sequence d (n).

Specifically, in the fourth embodiment of the present invention, the sequence d (n) is mapped onto L +1 consecutive frequency domain subcarriers from d (0) to d (L). The L +1 consecutive non-spaced frequency domain subcarriers may include a DC subcarrier, or may not include a DC subcarrier.

Specifically, in the fourth embodiment of the present invention, after the frequency domain mapping of the sequence d (n) is completed according to the above method, SC-FDMA conversion is performed on the obtained frequency domain signal, the frequency domain signal is converted into a time domain signal, and a synchronous baseband signal s (n) is generated and sent out.

Therefore, the method for transmitting the signal for synchronization according to the fourth embodiment of the present invention is implemented.

It should be noted that, the receiver structure of the fourth embodiment of the present invention is similar to that of the third embodiment of the present invention, and the difference is that the receiver of the fourth embodiment does not filter out the frequency offset of the 1/2 carriers before the baseband signal in the process of receiving the synchronization signal. That is, the baseband signal of the synchronization signal includes the frequency offset of the 1/2 carriers introduced in the SC-FDMA modulation process.

This difference is that, in the fourth embodiment of the present invention, the sampling signal s (n) of the generated SC-FDMA baseband signal s has an anti-center symmetry, that is:

s(n)＝-s(N-n),n＝1,2,...,N-1 (33)

wherein N is the number of sampling points.

And, when v ═ L-u, the sequence s_u(n) and the sequence s_v(n) has the characteristics of reverse conjugate equality between:

after receiving the oversampled version of the signal s (n), the receiver may perform simplified operations of receiving matched filtering according to the features of the above equation (33) and the above equation (34).

The above-mentioned method for transmitting the synchronization signal according to the embodiment of the present invention is described in detail with reference to three specific embodiments. As can be seen from the foregoing embodiments, in the method according to the second embodiment of the present invention, the perfect sequence b (n) is used to generate the sequence D (n) of the synchronization signal for D2D, so that the synchronization signal obtained by using the second embodiment of the present invention is different from the PSS, the problem of signal detection error of the D2D system caused by the fact that the synchronization signal of D2D is the same as the PSS is avoided, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

Further, in the second and fourth embodiments of the present invention, a perfect sequence (e.g., ZC sequence or GCL sequence) of odd length long by L is used to generate a sequence of even length long by L + 1. Compared with the existing method for generating the even-numbered sequence with the length of L-1 from the odd-numbered sequence, the method for selecting the parameters of the sequence generated by the embodiment of the invention has the advantage that the method for selecting the parameters is more.

Furthermore, the methods described in the third and fourth embodiments of the present invention can be applied to a frequency domain SC-FDMA modulation scenario, and solve the problem that the method in the prior art cannot be directly applied to a system of an SC-FDMA modulation scheme.

Corresponding to the signal sending method for synchronization provided by the embodiment of the invention, the embodiment of the invention also provides a signal sending device for synchronization. Fig. 8 is a block diagram of a signal transmitting apparatus for synchronization according to an embodiment of the present invention.

As shown in fig. 8, the apparatus may include: a first generating unit 801, a second generating unit 802, a radio frequency processing unit 803 and a transmitting unit 804.

The first generating unit 801 is configured to generate a sequence d (n) for a synchronization signal using the sequence b (n); wherein the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n).

The second generating unit 802 is configured to map the sequence d (n) to a corresponding resource location, and generate a synchronized baseband signal s.

The radio frequency processing unit 803 is configured to perform radio frequency processing on the baseband signal s.

The sending unit 804 is configured to send out the signal processed by the radio frequency processing unit 803.

In the apparatus according to the embodiment of the present invention, the sequence d (n) for the synchronization signal is generated by using the sequence b (n), and the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n). While typical PSS are generated from odd sequences of length L to even sequences of length L-1. Therefore, the synchronization signal of the D2D obtained by the embodiment of the invention is different from the PSS, the problem of signal detection error of the D2D system caused by the fact that the synchronization signal of the D2D is the same as the PSS is solved, and the synchronization performance and the communication performance of the D2D communication system are effectively improved.

Preferably, the sequence b (n) may be: the original value of the perfect sequence; or, the perfect sequence is generated after Discrete Fourier Transform (DFT); or, the perfect sequence is generated after IDFT.

Wherein, the perfect sequence can be a ZC sequence or a GCL sequence.

In the first case, the length of the sequence for the synchronization signal generated by the embodiment of the present invention is odd, and the method can be directly applied to a time domain scenario or a frequency domain scenario using multi-carrier modulation.

At this time, the first generation unit 801 generates the sequence d (n) using the following equation:

wherein L is an odd number.

Specifically, the sequence b (n) may be:

Correspondingly, the sequence d (n) generated by the first generation unit 801 is:

wherein u is the root sequence number of the sequence d (n).

Alternatively, the sequence d (n) generated by the first generation unit 801 may be:

wherein u is the root sequence number of the sequence d (n).

In the first case, the second generating unit 802 may include:

Further, the second generating unit 802 may further include:

Preferably, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1 (16)

wherein, N is the number of sampling points of s (N);

Further, the second generating unit 802 may further include:

Correspondingly, the second generating unit 802 further includes:

Preferably, the sampling signal s (n) of the baseband signal s has an anti-centrosymmetry and an anti-conjugate equality; respectively as follows:

s(n)＝-s(N-n),n＝1,2,...,N-1 (33)

wherein, N is the number of sampling points of s (N);

In the second case, the length of the sequence for the synchronization signal generated by the embodiment of the present invention is even, and the method can be directly applied to a time domain scenario or a frequency domain SC-FDMA modulation scenario without a DC carrier.

d(n)＝b(n),n＝0,1,...,L-1 (18)

wherein L is an even number.

Specifically, the sequence b (n) is:

In a second case, the second generating unit 802 may include:

Further, the second generating unit 802 may further include:

Preferably, the second generating unit 802 further includes:

Specifically, a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1 (28)

wherein, N is the number of sampling points of s (N);

wherein v is 2m L-u, m being an integer; u and v are the root sequence number of s (n), s_u(n) and s_v(n) is s (n) an expression using root sequence numbers u and v.

The embodiments in the present specification are described in a progressive manner, and the same and similar parts among the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. In particular, for the system embodiment, since it is substantially similar to the method embodiment, the description is simple, and for the relevant points, reference may be made to the partial description of the method embodiment.

The above-described embodiments of the present invention do not limit the scope of the present invention. Any modification, equivalent replacement, and improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A signal transmission apparatus for synchronization, the apparatus comprising:

the transmitting unit is used for transmitting the signals processed by the radio frequency processing unit;

the first generation unit generates the sequence d (n) using the following formula:

wherein L is an odd number.

2. The signaling apparatus for synchronization according to claim 1, wherein said sequence b (n) is:

the original value of the perfect sequence;

or,

the perfect sequence is generated after Discrete Fourier Transform (DFT);

or,

wherein the perfect sequence is a ZC sequence or a GCL sequence.

3. The signaling apparatus for synchronization according to claim 1, wherein said sequence b (n) is:

4. The signal transmission apparatus for synchronization according to claim 3, wherein the sequence d (n) generated by the first generation unit is:

wherein u is the root sequence number of the sequence d (n).

5. The signal transmission apparatus for synchronization according to claim 4, wherein the sequence d (n) generated by the first generation unit is:

wherein u is the root sequence number of the sequence d (n).

6. The signal transmission apparatus for synchronization according to any one of claims 1 to 5, wherein the second generation unit includes:

7. The signal transmission apparatus for synchronization according to claim 6, wherein the second generation unit further comprises:

8. The signal transmission apparatus for synchronization according to claim 7, wherein a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

9. The signal transmission apparatus for synchronization according to any one of claims 1 to 5, wherein the second generation unit includes:

10. The signal transmission apparatus for synchronization according to claim 9, wherein the second generation unit further includes:

11. The signal transmission apparatus for synchronization according to claim 10, wherein a sampling signal s (n) of the baseband signal s has an anti-centrosymmetry and an anti-conjugate equality; respectively as follows:

s(n)＝-s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

wherein v ═ L-u, u and v are the root sequence numbers of s (n), and s is_u(n) and s_v(n) is s (n) useExpressions for root sequence numbers u and v are shown.

12. The signal transmission apparatus for synchronization according to claim 1 or 2, wherein the first generation unit generates the sequence d (n) using the following equation:

d(n)＝b(n),n＝0,1,...,L-1

wherein L is an even number.

13. The signaling apparatus for synchronization according to claim 12, wherein said sequence b (n) is:

14. The signal transmission apparatus for synchronization according to claim 12, wherein the second generation unit includes:

15. The signal transmission apparatus for synchronization according to claim 14, wherein the second generation unit further comprises:

16. The signal transmission apparatus for synchronization according to claim 12, wherein the second generation unit further comprises:

17. The signal transmission apparatus for synchronization according to claim 16, wherein a sampling signal s (n) of the baseband signal s has central symmetry and conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

18. A method for signaling synchronization, the method comprising:

wherein the length of the sequence d (n) for the synchronization signal is not less than the length of the sequence b (n);

the generating of the sequence d (n) for the synchronization signal using the sequence b (n) comprises:

wherein L is an odd number.

19. The method according to claim 18, wherein the sequence b (n) is:

the original value of the perfect sequence;

or,

the perfect sequence is generated after Discrete Fourier Transform (DFT);

or,

wherein the perfect sequence is a ZC sequence or a GCL sequence.

20. The method according to claim 18, wherein the sequence b (n) is:

21. The method of claim 20, wherein the sequence d (n) is:

wherein u is the root sequence number of the sequence d (n).

22. The method of claim 20, wherein the sequence d (n) is:

wherein u is the root sequence number of the sequence d (n).

23. The method according to any of claims 18 to 22, wherein mapping the sequence d (n) to a corresponding resource location comprises:

the data on the subcarrier with the index of k is 0;

24. The method according to claim 23, characterized in that said synchronized baseband signal s is generated by means of orthogonal frequency division multiplexing, OFDM.

25. The method according to claim 24, characterized in that the sampled signal s (n) of the baseband signal s has a central symmetry and a conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

26. The method according to any of claims 18 to 22, wherein mapping the sequence d (n) to a corresponding resource location comprises:

27. The method according to claim 26, characterized in that the synchronized baseband signal s is generated by means of single carrier frequency division multiple access, SC-FDMA.

28. The method according to claim 27, wherein the sampled signal s (n) of the baseband signal s has an anti-centrosymmetry and an anti-conjugate equality; respectively as follows:

s(n)＝-s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);

29. The method according to claim 18 or 19, wherein the generating of the sequence d (n) for the synchronization signal using the sequence b (n) comprises:

d(n)＝b(n),n＝0,1,...,L-1

wherein L is an even number.

30. The method according to claim 29, wherein the sequence b (n) is:

31. The method of claim 29, wherein mapping the sequence d (n) to a corresponding resource location comprises:

32. The method according to claim 31, characterized in that the synchronized baseband signal s is generated using the method of single carrier frequency division multiple access, SC-FDMA.

33. The method of claim 29, wherein generating the synchronized baseband signal s comprises:

34. The method according to claim 33, wherein the sampled signal s (n) of the baseband signal s has a central symmetry and a conjugate equality; respectively as follows:

s(n)＝s(N-n),n＝1,2,...,N-1

wherein, N is the number of sampling points of s (N);