CN103906103A - Method and system for detecting main synchronous signal in LTE system - Google Patents
Method and system for detecting main synchronous signal in LTE system Download PDFInfo
- Publication number
- CN103906103A CN103906103A CN201210587831.4A CN201210587831A CN103906103A CN 103906103 A CN103906103 A CN 103906103A CN 201210587831 A CN201210587831 A CN 201210587831A CN 103906103 A CN103906103 A CN 103906103A
- Authority
- CN
- China
- Prior art keywords
- opt
- mrow
- search term
- pwr
- synchronization signal
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
- 238000000034 method Methods 0.000 title claims abstract description 43
- 230000001360 synchronised effect Effects 0.000 title claims abstract description 10
- 238000001514 detection method Methods 0.000 claims abstract description 29
- 125000004122 cyclic group Chemical group 0.000 claims description 5
- 108700041286 delta Proteins 0.000 claims description 5
- 230000007774 longterm Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 238000010295 mobile communication Methods 0.000 description 4
- 238000005516 engineering process Methods 0.000 description 3
- 238000004364 calculation method Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 238000005070 sampling Methods 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000012935 Averaging Methods 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 238000007630 basic procedure Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000004422 calculation algorithm Methods 0.000 description 1
- 230000001413 cellular effect Effects 0.000 description 1
- 230000006854 communication Effects 0.000 description 1
- 238000012937 correction Methods 0.000 description 1
- 238000012217 deletion Methods 0.000 description 1
- 230000037430 deletion Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 239000004576 sand Substances 0.000 description 1
Images
Landscapes
- Mobile Radio Communication Systems (AREA)
- Synchronisation In Digital Transmission Systems (AREA)
Abstract
The invention provides a method and system for detecting a main synchronous signal in an LTE system. A related power curve /r(tau)/2 is relatively obtained through the main synchronous signal and a receiving signal under pre-added frequency offset fofst, the frequency offset between the receiving signal and the main synchronous signal can be compensated for through the pre-added frequency offset fofst, and therefore the main synchronous signal is easily detected, and reliability of detection of the main synchronous signal is improved.
Description
Technical Field
The invention relates to the technical field of mobile communication, in particular to a method and a system for detecting a primary synchronization signal in an LTE (Long term evolution) system.
Background
With the continuous development of mobile communication and broadband wireless access technologies, long term evolution lte (long term evolution) technology becomes the mainstream technology for the development of new-generation mobile communication with the advantages of its high transmission rate, small user plane delay, and support for high-speed movement of a terminal. For cellular mobile communication systems, cell search is the first step of a mobile terminal accessing a wireless network, and is one of the most basic procedures of the physical layer. When the terminal is started up for the first time to access the cell and perform handover, cell search is needed to establish time-frequency synchronization, the number in the physical layer cell group and other system configuration information are obtained, and after the terminal is accessed to the cell, the terminal can receive the cell system information, establish connection and perform a communication process.
LTE cell search is achieved through primary synchronization signal (P-SCH) and secondary synchronization signal (S-SCH) detection. The primary synchronization signal and the secondary synchronization signal are periodically transmitted at a fixed location of each radio frame, and the specific locations thereof are shown in fig. 1. In the frequency domain, the main synchronization signal is generated by a Zadoff-Chu sequence in the frequency domain, and the values are as follows:
wherein the value of u is numbered by the cell identity group
The specific relationship between the two is determined as shown in the following table one:
watch 1
The primary synchronization signal is located in the middle of the system bandwidth, and occupies 62 subcarriers, and five subcarriers on two adjacent sides of the primary synchronization signal are reserved and not used, and the frequency domain structure is shown in fig. 2.
In both time domain and frequency domain, the primary synchronization signal has good autocorrelation and cross-correlation characteristics, and 3 groups are provided for completing symbol timing and frequency offset correction, and simultaneously carrying the numbered information in the cell identification group. The prior art scheme utilizes the good auto-correlation and cross-correlation properties of the primary synchronization signal for multiple groups (fixed 10 groups)Averaging and combining the positions of the correlation peaks of the continuous 5ms time domain signal and the time domain primary synchronization signal to find the position of the correlation peak with the highest possibility, thereby determining the number in the cell identification group
However, in the LTE system, signals may be configured on multiple frequency bands, specifically please refer to the following table two:
watch two
In each frequency band, the interval of the center frequency points of adjacent channels is 100kHz, and the center frequency point is integral multiple of 100 kHz. LTE has a number of possible bandwidths, including 1.4MHz, 3MHz, 5MHz, 10MHz, 15MHz, and 20 MHz. For each bandwidth configuration, the synchronization signal is located at the middle 0.96MHz of the system bandwidth. The frequency point grid is 100kHz, so that the number of possible center frequency points in each frequency band is large, and the bandwidth is variable, so that the center frequency point is more difficult to determine. Taking band 40 (2300 MHz 2400 MHz) as an example, the possible number of center frequency points is about 1000 (here, the influence at the band boundary is not considered). The existing terminal implementation method is to obtain a group of central frequency point lists (with an interval of 100 kHz) ordered according to the possibility, and then to take out a central frequency point f from the lists in sequenceiAt fiAnd detecting the master synchronization signal. Mainly at fi+ΔfBA primary synchronization signal is detected at the frequency. When | Δ fBIf | is large, the probability that the primary synchronization signal cannot be detected increases sharply, and once f is reachedi+ΔfBThe receiver will jump to the next central frequency point f without detecting the main synchronous signaliContinue to detect because of | fj-fiThis will lose the chance of detecting the synchronization signal ≧ 100 kHz. In addition, in the prior art, when the channel environment is better, 10 groups of 5ms data still need to be received to complete the primary synchronization signalAnd the algorithm time complexity is high in number detection.
Disclosure of Invention
The invention aims to provide a method and a system for detecting a primary synchronization signal in an LTE (long term evolution) system, which aim to solve the problem that the primary synchronization signal is easy to be undetected in the prior art when the frequency offset is large.
In order to solve the above technical problem, the present invention provides a method for detecting a primary synchronization signal in an LTE system, where the method for detecting a primary synchronization signal in an LTE system includes:
configuring search terms, wherein each search term comprises synchronous code root u information and pre-applied frequency offset fofstInformation;
obtaining correlation peak information for the search term, comprising: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And the position of the correlation peak Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
And selecting a search term according to the acquired correlation peak information of the search term, and acquiring the main synchronization signal according to the synchronization code root u information in the search term.
Optionally, in the method for detecting a primary synchronization signal in an LTE system, acquiring correlation peak information of an enabling search term further includes: obtaining the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Where k is the record index.
Optionally, in the method for detecting a primary synchronization signal in an LTE system, the accumulated power pwr _ his [ i ] of a correlation peak is obtainedopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The method comprises the following steps:
in the same search term number ioptNext, the same correlation peak position Pos [ i ] existsopt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝Pwr[iopt,j]+pwr_his[iopt][k]Obtaining; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]X (1+ alpha), wherein 0 < alpha < 1.
Optionally, in the method for detecting a primary synchronization signal in an LTE system, the accumulated power pwr _ his [ i ] of a correlation peak is obtainedopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Further comprising:
in the same search term number ioptNext, there are adjacent correlation peak positions Pos [ i ]opt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝2-(Δ1+β)×Pwr[iopt,j]+pwr_his[iopt][k]Obtaining, wherein delta 1 belongs to {1,2,3}, and beta is more than 1 and less than 3; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]+22-Δ2Obtaining, wherein delta 2 is larger than {1,2 }.
Optionally, in the method for detecting a primary synchronization signal in an LTE system, selecting a search term includes:
obtaining a score [ i ] for a search termopt][k]Wherein, score [ i ]opt][k]＝pwr_his[iopt][k]×adj[iopt][k]；
Score for search term score [ i ]opt][k]Sorting and selecting the maximum value
And second maximum value
When in use
When 1 is more than lambda and less than 3, the maximum value is selected
The corresponding search term.
Optionally, in the method for detecting a primary synchronization signal in an LTE system, the maximum value is used
If not selected, the search term score [ i [ ] is assignedopt][k]And threshold gammaSCMaking a comparison when the search term is numbered ioptAll score [ i ] belowopt][k]Are all less than a threshold gammaSCWhen the search term is discarded, wherein
0.125＜γ＜0.5
Represents all search terms score [ i ]opt][k]Average value of (a).
Optionally, in the method for detecting a primary synchronization signal in an LTE system, the frequency offset f is pre-addedofstThe value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }.
Optionally, in the method for detecting a primary synchronization signal in the LTE system, the correlation power curve | r (τ) > is obtained as follows2：
Dividing the received time domain signal r (n) into M segments to obtain ri(m), wherein N is 0,1s-1，i＝0,1,...M-1；
To ri(m) performing a fast Fourier transform to obtain Ri(k)；
To Ri(k) Performing cyclic shift to obtain
Wherein,
obtaining a segment correlation power | ri(τ)|2Wherein <math>
<mrow>
<msup>
<mrow>
<mo>|</mo>
<msub>
<mi>r</mi>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>τ</mi>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>|</mo>
<mi>IFFT</mi>
<mrow>
<mo>(</mo>
<msub>
<mover>
<mi>R</mi>
<mo>~</mo>
</mover>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>·</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>P</mi>
<mrow>
<mi>P</mi>
<mo>-</mo>
<mi>SCH</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>)</mo>
</mrow>
<mo>*</mo>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>;</mo>
</mrow>
</math>
for segment correlation power | ri(τ)|2Splicing to obtain the associated power curve | r (tau) converter2。
The invention also provides a primary synchronization signal detection system in the LTE system, which comprises:
a search term configuration module for configuring search terms, each search term including information of synchronization code root u and pre-applied frequency offset fofstInformation;
the correlation peak information acquisition module is used for acquiring correlation peak information of the search term and comprises the following steps: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And the position of the correlation peak Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
And the main synchronization signal determining module is used for selecting a search term according to the acquired correlation peak information of the search term and acquiring the main synchronization signal according to the synchronization code root u information in the search term.
Optionally, in the primary synchronization signal detection system in the LTE system, the acquiring of the correlation peak information of the enabling search term by the correlation peak information acquiring module further includes: obtaining the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Where k is the record index.
Optionally, in the primary synchronization signal detection system in the LTE system, the correlation peak information obtaining module obtains the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The method comprises the following steps:
in the same search term number ioptNext, the same correlation peak position Pos [ i ] existsopt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝Pwr[iopt,j]+pwr_his[iopt][k]Obtaining; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]X (1+ alpha), wherein 0 < alpha < 1.
Optionally, in the primary synchronization signal detection system in the LTE system, the correlation peak information obtaining module obtains the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And degree of positional adjacency of correlation peaksadj[iopt][k]Further comprising:
in the same search term number ioptNext, there are adjacent correlation peak positions Pos [ i ]opt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝2-(Δ1+β)×Pwr[iopt,j]+pwr_his[iopt][k]Obtaining, wherein delta 1 belongs to {1,2,3}, and beta is more than 1 and less than 3; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]+22-Δ2Obtaining, wherein delta 2 is larger than {1,2 }.
Optionally, in the primary synchronization signal detection system in the LTE system, the selecting a search term by the primary synchronization signal determining module includes:
obtaining a score [ i ] for a search termopt][k]Wherein, score [ i ]opt][k]＝pwr_his[iopt][k]×adj[iopt][k]；
Score for search term score [ i ]opt][k]Sorting and selecting the maximum value
And second maximum value
When in use
When 1 is more than lambda and less than 3, the maximum value is selected
The corresponding search term.
Optionally, in the primary synchronization signal detection system in the LTE system, the primary synchronization signal determining module is configured to determine a maximum value of the primary synchronization signal
If not selected, search terms are selectedScore [ i ]opt][k]And threshold gammaSCMaking a comparison when the search term is numbered ioptAll score [ i ] belowopt][k]Are all less than a threshold gammaSCWhen the search term is discarded, wherein0.125＜γ＜0.5
Represents all search terms score [ i ]opt][k]Average value of (a).
Optionally, in the primary synchronization signal detection system in the LTE system, the pre-offset fofstThe value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }.
Optionally, in the primary synchronization signal detection system in the LTE system, the correlation peak information obtaining module obtains the correlation power curve | r (τ) | n according to the following method2：
Dividing the received time domain signal r (n) into M segments to obtain ri(m), wherein N is 0,1s-1，i＝0,1,...M-1；
To ri(m) performing a fast Fourier transform to obtain Ri(k)；
To Ri(k) Performing cyclic shift to obtain
Wherein,
obtaining a segment correlation power | ri(τ)|2Wherein <math>
<mrow>
<msup>
<mrow>
<mo>|</mo>
<msub>
<mi>r</mi>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>τ</mi>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>|</mo>
<mi>IFFT</mi>
<mrow>
<mo>(</mo>
<msub>
<mover>
<mi>R</mi>
<mo>~</mo>
</mover>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>·</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>P</mi>
<mrow>
<mi>P</mi>
<mo>-</mo>
<mi>SCH</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>)</mo>
</mrow>
<mo>*</mo>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>;</mo>
</mrow>
</math>
for segment correlation power | ri(τ)|2Splicing to obtain the associated power curve | r (tau) converter2。
In the method and system for detecting the primary synchronization signal in the LTE system provided by the invention, the related power curve | r (tau) <' > is not calculation2By pre-biasing fofstThe primary synchronization signal is acquired in relation to the received signal, thereby enabling the use of a pre-offset fofstThe frequency offset between the received signal and the master synchronizing signal is compensated, so that the master synchronizing signal is easy to detect, and the reliability of the detection of the master synchronizing signal is improved.
Drawings
FIG. 1 is a schematic diagram of the location of a synchronization signal in the time domain;
FIG. 2 is a schematic diagram of a structure of a primary synchronization signal in a frequency domain;
fig. 3 is a flowchart illustrating a primary synchronization signal detection method in an LTE system according to an embodiment of the present invention;
fig. 4 is a schematic block diagram of a primary synchronization signal detection system in an LTE system according to an embodiment of the present invention.
Detailed Description
The following describes the method and system for detecting a primary synchronization signal in an LTE system in detail with reference to the accompanying drawings and specific embodiments. Advantages and features of the present invention will become apparent from the following description and from the claims. It is to be noted that the drawings are in a very simplified form and are not to precise scale, which is merely for the purpose of facilitating and distinctly claiming the embodiments of the present invention.
Please refer to fig. 3, which is a flowchart illustrating a primary synchronization signal detection method in an LTE system according to an embodiment of the present invention. As shown in fig. 3, the method for detecting a primary synchronization signal in an LTE system includes:
s30: configuring search terms, wherein each search term comprises synchronous code root u information and pre-applied frequency offset fofstInformation;
s31: obtaining correlation peak information for the search term, comprising: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And the position of the correlation peak Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
S32: and selecting a search term according to the acquired correlation peak information of the search term, and acquiring the main synchronization signal according to the synchronization code root u information in the search term.
Accordingly, the present embodiment further provides a primary synchronization signal detection system in an LTE system, and specifically, please refer to fig. 4, which is a schematic block diagram of the primary synchronization signal detection system in the LTE system according to the embodiment of the present invention. As shown in fig. 4, the primary synchronization signal detection system in the LTE system includes:
a search term configuration module 40 for configuring search terms, each search term comprising information of synchronization code root u and pre-biased frequency fofstInformation;
the correlation peak information obtaining module 41 is configured to obtain correlation peak information of the search term, and includes: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And the position of the correlation peak Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
And the master synchronization signal determining module 42 is configured to select a search term according to the obtained correlation peak information of the search term, and obtain a master synchronization signal from the synchronization code root u information in the search term.
Wherein the synchronization code root u belongs to {25,29,34}, that is, the synchronization code root u and the serial number in the cell identification group
And (7) corresponding. Preferably, the pre-frequency offset fofstThe value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }. Here, the pre-biased frequency deviation f is obtained according to the simulation resultofstThe preferable value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }; in other embodiments of the present invention, the pre-biased frequency offset f is set when the channel state changesofstOther frequency values may also be taken.
In this embodiment, each search term may further include an enable signal Flag, and the enable signal Flag is used to indicate whether a correlation peak information acquisition operation needs to be performed on the search term, so that the process may be simplified.
In this embodiment, the correlation peak information enabling the search term is obtainedThe method also comprises the following steps: obtaining the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Where k is the record index. Here, the adjacency degree adj [ iopt][k]Position Pos [ i ] according to one or more correlation peaks (wherein the correlation peaks are obtained by receiving data for 5ms for multiple times, which is prior art and is not described herein again)opt,j]The spacing/relationship between them is obtained. Wherein the numbers i are based on the same search termoptNext, the difference in the positional relationship between correlation peaks, the accumulated power pwr _ his [ i [ ]opt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The method can be specifically determined by the following method:
in the same search term number ioptNext, the same correlation peak position Pos [ i ] existsopt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝Pwr[iopt,j]+pwr_his[iopt][k]Obtaining; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]X (1+ alpha), wherein alpha is more than 0 and less than 1;
in the same search term number ioptNext, there are adjacent correlation peak positions Pos [ i ]opt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝2-(Δ1+β)×Pwr[iopt,j]+pwr_his[iopt][k]Obtaining, wherein delta 1 belongs to {1,2,3}, and beta is more than 1 and less than 3; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]+22-Δ2Obtaining, wherein delta 2 is larger than {1,2 }.
In addition, when the same search term number ioptNext, Pos [ i ] can be set when the correlation peaks are neither in the same position nor adjacent to each otheropt,j]And Pwr [ i ]opt,j]And adding the correlation peak information to the end of each search term record, namely performing a record work of the correlation peak information. At the same time, it can also be used for adj [ iopt][k]An initial value is set, which can be selected according to the channel status, for example, an initial value of 8,this application is not limited thereto.
In this embodiment, a search term is specifically selected by the following method, so that the master synchronization signal is obtained from the selected search term:
obtaining a score [ i ] for a search termopt][k]Wherein, score [ i ]opt][k]＝pwr_his[iopt][k]×adj[iopt][k]；
Score for search term score [ i ]opt][k]Sorting and selecting the maximum valueAnd second maximum value
When in useWhen 1 is more than lambda and less than 3, the maximum value is selected
The corresponding search term.
Here, the accumulated power pwr _ his [ i ] is passed through the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The performance of the corresponding search term is obtained, here with a score [ i [ ]opt][k]And (5) characterizing. Satisfied when the search term with the best performance is between the search term with the second best performance
And then, according to the simulation result, the search term with the optimal performance can be selected, so that the main synchronization signal is obtained.
In this embodiment, when a search term cannot be selected temporarily, a search term deletion operation is further performed on a plurality of search terms to be selected, specifically, the following method is implemented:
score the search term score [ i ]opt][k]And threshold gammaSCMaking a comparison when the search term is numbered ioptAll score [ i ] belowopt][k]Are all less than a threshold gammaSCWhen the search term is discarded, wherein
0.125＜γ＜0.5
Represents all search terms score [ i ]opt][k]Average value of (a).
By the method, the search terms are deleted to a certain extent until the last search term is left, so that the search term is the selected search term, and the main synchronization signal is determined according to the selected search term.
According to the method, under the optimal condition, the main synchronizing signal can be obtained only by receiving one 5ms of data, so that the detection process of the main synchronizing signal is greatly simplified.
Furthermore, in this embodiment, the correlation power curve | r (τ) is obtained by segmenting the signal2Thereby simplifying calculation of the correlation power curve | r (tau) & lt2The specific method of the acquisition process is as follows:
dividing the received time domain signal r (n) into M segments to obtain ri(m), wherein N is 0,1s-1，i＝0,1,...M-1，m＝0,1,...NFFT-1; preferably, adjacent segments overlap by NovA sampling point, where M and NovThe value of (a) can be flexibly adjusted according to actual requirements, and is in the last section rM-1(m) end padding 0.
To ri(m) performing a fast Fourier transform to obtain Ri(k)；
To Ri(k) Performing cyclic shift to obtain
Wherein,
wherein<·>NMeaning taking the modulus of the positive integer N, making the sampling rate of the received signal fsAnd f is andsadjustable, FFT point number NFFTCan be adjusted according to actual requirements, then
Adjacent frequency point spacing equal to deltaf＝fs·(NFFT)-1Then, there is a relationship: f. ofofst＝Δofst·Δf
Obtaining a segment correlation power | ri(τ)|2Wherein <math>
<mrow>
<msup>
<mrow>
<mo>|</mo>
<msub>
<mi>r</mi>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>τ</mi>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>|</mo>
<mi>IFFT</mi>
<mrow>
<mo>(</mo>
<msub>
<mover>
<mi>R</mi>
<mo>~</mo>
</mover>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>·</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>P</mi>
<mrow>
<mi>P</mi>
<mo>-</mo>
<mi>SCH</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>)</mo>
</mrow>
<mo>*</mo>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>;</mo>
</mrow>
</math> where (-) is a conjugate operation, IFFT (-) is a fast inverse Fourier transform, PP-SCH(k) Is a primary synchronization code frequency domain signal.
For segment correlation power | ri(τ)|2Splicing to obtain the associated power curve | r (tau) converter2。
Wherein the correlation power curve | r (τ) converter2The acquisition method has the following theoretical basis:
the correlation of the time domain signals x (n) and y (n) is denoted as:
fourier transforms of x (n) and y (n) into X (K) and Y (K), theoretical analysis proves
And X*(k) Y (k) is a pair of fourier transforms, so correlation can be achieved quickly with an FFT.
In summary, in the present embodiment, the correlation power curve | r (τ) & ltY & gt is zero2By pre-biasing fofstThe primary synchronization signal is acquired in relation to the received signal, thereby enabling the use of a pre-offset fofstThe frequency offset between the received signal and the master synchronizing signal is compensated, so that the master synchronizing signal is easy to detect, and the reliability of the detection of the master synchronizing signal is improved.
The above description is only for the purpose of describing the preferred embodiments of the present invention, and is not intended to limit the scope of the present invention, and any variations and modifications made by those skilled in the art based on the above disclosure are within the scope of the appended claims.
Claims (16)
1. A method for detecting a primary synchronization signal in an LTE system is characterized by comprising the following steps:
configuring search terms, wherein each search term comprises synchronous code root u information and pre-applied frequency offset fofstInformation;
obtaining correlation peak information for the search term, comprising: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And correlation peak ofPosition Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
And selecting a search term according to the acquired correlation peak information of the search term, and acquiring the main synchronization signal according to the synchronization code root u information in the search term.
2. The method of detecting a primary synchronization signal in an LTE system as claimed in claim 1, wherein obtaining the correlation peak information of the enabling search term further comprises: obtaining the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Where k is the record index.
3. The method of claim 2, wherein the accumulated power pwr _ his [ i ] of the correlation peak is obtainedopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The method comprises the following steps:
in the same search term number ioptNext, the same correlation peak position Pos [ i ] existsopt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝Pwr[iopt,j]+pwr_his[iopt][k]Obtaining; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]X (1+ alpha), wherein 0 < alpha < 1.
4. The method of claim 2, wherein the accumulated power pwr _ his [ i ] of the correlation peak is obtainedopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Further comprising:
in the same search term number ioptNext, there are adjacent correlation peak positions Pos [ i ]opt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝2-(Δ1+β)×Pwr[iopt,j]+pwr_his[iopt][k]Obtaining, wherein delta 1 belongs to {1,2,3}, and beta is more than 1 and less than 3; said positions being adjacent to each otherDegree adj [ iopt][k]According to adj [ iopt][k]＝adj[iopt][k]+22-Δ2Obtaining, wherein delta 2 is larger than {1,2 }.
5. The method of detecting primary synchronization signal in LTE system as claimed in claim 2, wherein selecting a search term comprises:
obtaining a score [ i ] for a search termopt][k]Wherein, score [ i ]opt][k]＝pwr_his[iopt][k]×adj[iopt][k]；
Score for search term score [ i ]opt][k]Sorting and selecting the maximum value
And second maximum value
When in use
When 1 is more than lambda and less than 3, the maximum value is selected
The corresponding search term.
6. The method of detecting primary synchronization signal in LTE system of claim 5 wherein, when maximum value is reachedIf not selected, the search term score [ i [ ] is assignedopt][k]And threshold gammaSCMaking a comparison when the search term is numbered ioptAll score [ i ] belowopt][k]Are all less than a threshold gammaSCWhen the search term is discarded, wherein
0.125＜γ＜0.5
Represents all search terms score [ i ]opt][k]Average value of (a).
7. Method for primary synchronization signal detection in an LTE system according to any of claims 1 to 6 characterized in that said pre-frequency offset fofstThe value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }.
8. Method for primary synchronization signal detection in an LTE system according to any of claims 1 to 6 wherein said correlation power curve | r (τ) is obtained as follows2：
Dividing the received time domain signal r (n) into M segments to obtain ri(m), wherein N is 0,1s-1，i＝0,1,...M-1；
To ri(m) performing a fast Fourier transform to obtain Ri(k)；
To Ri(k) Performing cyclic shift to obtain
Wherein,
obtaining a segment correlation power | ri(τ)|2Wherein <math>
<mrow>
<msup>
<mrow>
<mo>|</mo>
<msub>
<mi>r</mi>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>τ</mi>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>|</mo>
<mi>IFFT</mi>
<mrow>
<mo>(</mo>
<msub>
<mover>
<mi>R</mi>
<mo>~</mo>
</mover>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>·</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>P</mi>
<mrow>
<mi>P</mi>
<mo>-</mo>
<mi>SCH</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>)</mo>
</mrow>
<mo>*</mo>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>;</mo>
</mrow>
</math>
for segment correlation power | ri(τ)|2Splicing to obtain the associated power curve | r (tau) converter2。
9. A primary synchronization signal detection system in an LTE system, comprising:
a search term configuration module for configuring search terms, each search term including information of synchronization code root u and pre-applied frequency offset fofstInformation;
the correlation peak information acquisition module is used for acquiring correlation peak information of the search term and comprises the following steps: obtaining pre-applied frequency deviation fofstLower primary synchronization signal and associated power curve | r (tau) of received signal2(ii) a Obtaining a correlation power curve | r (τ) visually2Middle front NmaxPower Pwr [ i ] of maximum correlation peakopt,j]And the position of the correlation peak Pos [ i ]opt,j]Wherein ioptRepresents the search term number, j ∈ {0,1max-1}；
And the main synchronization signal determining module is used for selecting a search term according to the acquired correlation peak information of the search term and acquiring the main synchronization signal according to the synchronization code root u information in the search term.
10. The primary synchronization signal detection system in the LTE system as claimed in claim 9, wherein the correlation peak information obtaining module obtaining the correlation peak information of the enabled search term further comprises: obtaining the accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Where k is the record index.
11. The primary synchronization signal detection system in the LTE system according to claim 10, wherein the correlation peak information obtaining module obtains accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]The method comprises the following steps:
in the same search term number ioptNext, the same correlation peak position Pos [ i ] existsopt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝Pwr[iopt,j]+pwr_his[iopt][k]Obtaining; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]X (1+ alpha), wherein 0 < alpha < 1.
12. The primary synchronization signal detection system in the LTE system according to claim 10, wherein the correlation peak information obtaining module obtains accumulated power pwr _ his [ i ] of the correlation peakopt][k]And the degree of positional adjacency of the correlation peaks adj [ i ]opt][k]Further comprising:
in the same search term number ioptNext, there are adjacent correlation peak positions Pos [ i ]opt,j]While, the accumulated power pwr _ his [ i ]opt][k]According to pwr _ his [ i ]opt][k]＝2-(Δ1+β)×Pwr[iopt,j]+pwr_his[iopt][k]Obtaining, wherein delta 1 belongs to {1,2,3}, and beta is more than 1 and less than 3; the degree of positional adjacency adj [ i ]opt][k]According to adj [ iopt][k]＝adj[iopt][k]+22-Δ2Obtaining, wherein delta 2 is larger than {1,2 }.
13. The primary synchronization signal detection system of claim 10, wherein the primary synchronization signal determination module selects a search term comprising:
obtaining a score [ i ] for a search termopt][k]Wherein, score [ i ]opt][k]＝pwr_his[iopt][k]×adj[iopt][k]；
Score for search term score [ i ]opt][k]Sorting and selecting the maximum value
And second maximum value
When in use
When 1 is more than lambda and less than 3, the maximum value is selected
The corresponding search term.
14. The system for detecting primary synchronization signal in LTE system as claimed in claim 13, wherein said primary synchronization signal determining module determines the maximum valueIf not selected, the search term score [ i [ ] is assignedopt][k]And threshold gammaSCMaking a comparison when the search term is numbered ioptAll score [ i ] belowopt][k]Are all less than a threshold gammaSCWhen the search term is discarded, wherein
0.125＜γ＜0.5Represents all search terms score [ i ]opt][k]Average of (2)The value is obtained.
15. The primary synchronization signal detection system in LTE system of any of claims 9 to 14, wherein said pre-offset fofstThe value range of (1) is { -15kHz, -7.5kHz,0,7.5kHz,15kHz }.
16. The primary synchronization signal detection system in the LTE system according to any of claims 9 to 14, wherein the correlation peak information obtaining module obtains the correlation power curve | r (τ) | y2：
Dividing the received time domain signal r (n) into M segments to obtain ri(m), wherein N is 0,1s-1，i＝0,1,...M-1；
To ri(m) performing a fast Fourier transform to obtain Ri(k)；
To Ri(k) Performing cyclic shift to obtainWherein,
obtaining a segment correlation power | ri(τ)|2Wherein <math>
<mrow>
<msup>
<mrow>
<mo>|</mo>
<msub>
<mi>r</mi>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>τ</mi>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>=</mo>
<msup>
<mrow>
<mo>|</mo>
<mi>IFFT</mi>
<mrow>
<mo>(</mo>
<msub>
<mover>
<mi>R</mi>
<mo>~</mo>
</mover>
<mi>i</mi>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>·</mo>
<mrow>
<mo>(</mo>
<msub>
<mi>P</mi>
<mrow>
<mi>P</mi>
<mo>-</mo>
<mi>SCH</mi>
</mrow>
</msub>
<mrow>
<mo>(</mo>
<mi>k</mi>
<mo>)</mo>
</mrow>
<mo>)</mo>
</mrow>
<mo>*</mo>
<mo>)</mo>
</mrow>
<mo>|</mo>
</mrow>
<mn>2</mn>
</msup>
<mo>;</mo>
</mrow>
</math>
for segment correlation power | ri(τ)|2Splicing to obtain the associated power curve | r (tau) converter2。
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210587831.4A CN103906103B (en) | 2012-12-28 | 2012-12-28 | Master sync signal detection method and detecting system in LTE system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201210587831.4A CN103906103B (en) | 2012-12-28 | 2012-12-28 | Master sync signal detection method and detecting system in LTE system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN103906103A true CN103906103A (en) | 2014-07-02 |
| CN103906103B CN103906103B (en) | 2017-10-31 |
Family
ID=50997207
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201210587831.4A Active CN103906103B (en) | 2012-12-28 | 2012-12-28 | Master sync signal detection method and detecting system in LTE system |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN103906103B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114554525A (en) * | 2022-02-22 | 2022-05-27 | 上海星思半导体有限责任公司 | Signal processing method, signal processing apparatus, electronic device, storage medium, and program product |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102148785A (en) * | 2010-02-05 | 2011-08-10 | 中兴通讯股份有限公司 | Methods and devices for detecting main synchronous signal and generating sequence in LTE (Long Term Evolution) system |
| EP2383950A2 (en) * | 2010-03-10 | 2011-11-02 | Broadcom Corporation | A method and system for iterative multiple frequency hypothesis testing with cell-id detection in an e-ultra/lte ue receiver |
| CN102480455A (en) * | 2010-11-26 | 2012-05-30 | 联芯科技有限公司 | Detecting method and detecting device for primary synchronization signals in long-term evolution system |
-
2012
- 2012-12-28 CN CN201210587831.4A patent/CN103906103B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102148785A (en) * | 2010-02-05 | 2011-08-10 | 中兴通讯股份有限公司 | Methods and devices for detecting main synchronous signal and generating sequence in LTE (Long Term Evolution) system |
| EP2383950A2 (en) * | 2010-03-10 | 2011-11-02 | Broadcom Corporation | A method and system for iterative multiple frequency hypothesis testing with cell-id detection in an e-ultra/lte ue receiver |
| CN102480455A (en) * | 2010-11-26 | 2012-05-30 | 联芯科技有限公司 | Detecting method and detecting device for primary synchronization signals in long-term evolution system |
Non-Patent Citations (1)
| Title |
|---|
| 白海龙等: "FDD-LTE小区搜索同步信号检测算法研究", 《移动通信》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114554525A (en) * | 2022-02-22 | 2022-05-27 | 上海星思半导体有限责任公司 | Signal processing method, signal processing apparatus, electronic device, storage medium, and program product |
| CN114554525B (en) * | 2022-02-22 | 2024-02-06 | 上海星思半导体有限责任公司 | Signal processing method, device, electronic equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| CN103906103B (en) | 2017-10-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| TWI271048B (en) | Cell search method for orthogonal frequency division multiplexing based cellular communication system | |
| RU2464721C2 (en) | Methods and devices for synchronisation and detection in wireless communication systems | |
| CN101656700B (en) | Method and device for detecting cyclic prefix type during initial cell search in long-term evolution system | |
| CN107959922B (en) | Method and device for detecting main sidelink synchronization signal in D2D | |
| KR101895980B1 (en) | Method and apparatus for transmitting and receiving signal for searching for cell in wireless communication system | |
| EP2692176B1 (en) | Fast radio access technology detection for cell search | |
| US20140321450A1 (en) | Method, receiver and system for signal synchronization | |
| CN107820273B (en) | Method and device for detecting synchronization signal of sidelink in D2D | |
| US9065630B1 (en) | Systems and methods for detecting secondary synchronization signals in a wireless communication system | |
| RU2009130349A (en) | SECONDARY SYNCHRONIZATION SEQUENCES FOR DETECTION OF CELL GROUPS IN THE CELLULAR SYSTEM | |
| WO2014063275A1 (en) | Method for determining remote same-frequency interference source and locating method therefor | |
| US8630279B2 (en) | Method for generating downlink signal, and method for searching cell | |
| CN106797362A (en) | For cell search in wireless network and the signal format of synchronization | |
| WO2009082940A1 (en) | Method, system and apparatus for transmitting, receiving sync sequence | |
| CN104754623A (en) | Cell searching method and system based on interference elimination of LTE (Long Term Evolution) system | |
| CN105007095B (en) | Integer frequency offset estimation method and device during a kind of cell initial search | |
| CN102638801A (en) | Method and device for planning physical cell in long term evolution (LTE) system | |
| CN102857457B (en) | Time division duplexing-long term evolution (TDD-LTE) downlink synchronizing method | |
| CN103906103B (en) | Master sync signal detection method and detecting system in LTE system | |
| CN103002469B (en) | Method and device for detecting primary synchronous codes | |
| KR20110009552A (en) | The method of frame synchronization acquisition and the cell search method robust to a interference of multi-cell | |
| KR100874485B1 (en) | Method and apparatus andfor generating down link frame, method and apparatus for cell search in cellular syste | |
| KR20110009551A (en) | The location determination method based on the signal phase measurement in wireless network | |
| CN102695183B (en) | Signature detection and time bias estimation | |
| KR100819129B1 (en) | Method for generating downlink signal and method for searching cell |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20191106 Address after: 1-1-609-a, North Zone, financial and Trade Center, No. 6865, Asia Road, Tianjin Free Trade Zone (Dongjiang Free Trade Port Area), 300450 Patentee after: Huiyi finance leasing (Tianjin) Co., Ltd Address before: 201206, 1258, Mingyue Road, Pudong New Area, Shanghai, Pudong New Area Patentee before: Leadcore Technology Co., Ltd. |
|
| TR01 | Transfer of patent right | ||
| EE01 | Entry into force of recordation of patent licensing contract |
Application publication date: 20140702 Assignee: Leadcore Technology Co., Ltd. Assignor: Huiyi finance leasing (Tianjin) Co., Ltd Contract record no.: X2020980000019 Denomination of invention: Method and system for detecting main synchronous signal in LTE system Granted publication date: 20171031 License type: Exclusive License Record date: 20200106 |
|
| EE01 | Entry into force of recordation of patent licensing contract | ||
| TR01 | Transfer of patent right |
Effective date of registration: 20220317 Address after: 201206 Ming Yue Road, Pudong New Area, Shanghai, No. 1258 Patentee after: LEADCORE TECHNOLOGY Co.,Ltd. Address before: 300450 Tianjin pilot free trade zone (Dongjiang Bonded Port Area), 1-1-609-a, north area of financial and Trade Center, No. 6865, Asia Road Patentee before: Huiyi finance leasing (Tianjin) Co.,Ltd. |
|
| TR01 | Transfer of patent right |