CN101719890A - District searching method and d device applied to long-period evolution system - Google Patents

District searching method and d device applied to long-period evolution system Download PDF

Info

Publication number
CN101719890A
CN101719890A CN200910241826A CN200910241826A CN101719890A CN 101719890 A CN101719890 A CN 101719890A CN 200910241826 A CN200910241826 A CN 200910241826A CN 200910241826 A CN200910241826 A CN 200910241826A CN 101719890 A CN101719890 A CN 101719890A
Authority
CN
China
Prior art keywords
synchronous signals
auxiliary synchronous
master sync
sync signal
candidate detection
Prior art date
Application number
CN200910241826A
Other languages
Chinese (zh)
Other versions
CN101719890B (en
Inventor
许百成
Original Assignee
北京天碁科技有限公司
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by 北京天碁科技有限公司 filed Critical 北京天碁科技有限公司
Priority to CN2009102418266A priority Critical patent/CN101719890B/en
Publication of CN101719890A publication Critical patent/CN101719890A/en
Application granted granted Critical
Publication of CN101719890B publication Critical patent/CN101719890B/en

Links

Abstract

The invention provides district searching method and device applied to a long-period evolution system. The district searching method comprises the following steps of: A, acquiring symbol timing information and CP mode information according to the iterative characteristic of CP data; B, carrying out the fast Fourier transform of NFFT data points in an OFDM symbol according to symbol timing information to obtain frequency domain data of the OFDM symbol; C, extracting a first candidate detection signal from the frequency domain data of the OFDM symbol according to a corresponding subcarrier position of main and secondary synchronous signals in a frequency domain; D, detecting the ID and the position of the main synchronous signal according to the first candidate detection signal and the known main synchronous signal sequence; E, acquiring a second candidate detection signal of the secondary synchronous signal according to the position and the CP mode information of the main synchronous signal, and detecting the ID of the secondary synchronous signal according to the second candidate detection signal and the known secondary synchronous signal sequence, thereby obtaining frame synchronization information. According to the invention, the complicated design of a narrowband low-pass filter can be avoided, and the operand is reduced.

Description

A kind of small region search method and device that is applied to long evolving system

Technical field

The invention belongs to wireless communication technology field, particularly a kind of method and apparatus that is applied to the Cell searching of 3GPP LTE (Long Term Evolution of third generation partner plan) system.

Background technology

The LTE system is the evolution of 3G, it improves and has strengthened the aerial access technology of 3G, adopt OFDM (OFDM) and multiple-input and multiple-output (MIMO) sole criterion as its wireless network evolution, the peak rate of descending 100Mbit/s and up 50Mbit/s can be provided under the 20MHz spectral bandwidth, improved the performance of Cell Edge User, improve cell capacity, reduced system delay.

The LTE system is based on a kind of wireless communication system of OFDM technology, so the OFDM symbol is the base unit in its frame structure.Specifically, its frame structure constitutes in the following manner step by step: a radio frames is made of 10 subframes that (subframe 0#~9#), each subframe is made of 2 time slots, and each time slot is made of 6 or 7 OFDM symbols.

The same with existing wireless network, the LTE system also is a kind of cellular system of sub-district system.The id information of each sub-district is by N in the LTE system ID (1)And N ID (2)Two parts are formed, promptly N ID = N ID ( 1 ) + N ID ( 2 ) . Wherein, N ID (2)Information by master sync signal entrained (PSS, Primary Synchronization Signal), N ID ( 2 ) ∈ { 0,1,2 } , Each N ID (2)Corresponding specific known array; N ID (1)(SSS, SecondarySynchronization Signal) is entrained by auxiliary synchronous signals, N ID ( 1 ) ∈ { 0,1,2 . . . 167 } , Each N ID (1)Corresponding a pair of specific known array.

Primary/secondary synchronizing signal is positioned on 62 subcarriers in centre of specific OFDM symbol, is specifically to be distributed on each 31 subcarrier of direct current both sides, as shown in Figure 1.Direct current subcarrier among Fig. 1 and 5 idle sub-carrier do not send any signal, and the effect of idle sub-carrier is for providing a protection between primary/secondary synchronizing signal and the data-signal at interval.

Divide according to transmission means, there are FDD (Frequency Division Duplexing (FDD)) and two kinds of patterns of TDD (time division duplex) in the LTE system.With reference to Fig. 2, for fdd mode, master sync signal is positioned at last OFDM symbol of first time slot of 0# and 5# subframe; Auxiliary synchronous signals is positioned at the penult OFDM symbol of first time slot of 0# and 5# subframe.For tdd mode, master sync signal is positioned at the 3rd OFDM symbol of first time slot of 1# and 6# subframe; Auxiliary synchronous signals is positioned at last OFDM symbol of second time slot of 0# and 5# subframe.This shows that for any pattern, every frame all comprises two primary/secondary synchronizing signals.It should be noted that for master sync signal the signal of twice appearance is from same sequence, promptly master sync signal is to send in the cycle with the field, finds the master sync signal position also can only determine the original position of each field afterwards like this; For auxiliary synchronous signals, the signal of twice appearance is from two different sequences that satisfy certain relation, that is to say ID for same auxiliary synchronous signals, it is to send in the cycle with the frame that two sequences of S1 and S2 are arranged, determine that like this information of frame synchronization has also just obtained after the pairing particular sequence of auxiliary synchronous signals.

The LTE system is by introducing the intersymbol interference that Cyclic Prefix (CP) avoids multipath to bring, and promptly (length is N a symbol FFT, N FFTLength for fast Fourier transform (FFT) in the system) (length is N to the data of afterbody CP) to constitute a new length be N to the copy head that copies symbol to FFT+ N CPSymbol.The introducing of Cyclic Prefix makes the OFDM symbol have such characteristic, and promptly a part of data (CP) are according to certain intervals (N FFT) carry out repetition.In the LTE system, there are two kinds of patterns in CP: normal mode and mode of extension.For normal mode, CP length is shorter relatively, can hold 7 OFDM symbols in the time slot (length is 0.5ms), and the CP length N of first symbol CPN1CP length N with other symbols CPN2Compare longer a little, shown in (a) among Fig. 3.For mode of extension, the CP length N CPELonger relatively, be approximately about 3.6 times of CP length under the normal mode.Just because of this, under expansion CP pattern, the symbolic number that time slot can hold will be lacked than the normal mode formula, can only hold 6.The CP identical length of all symbols is same under the expansion CP pattern, shown in (b) among Fig. 3.In the LTE system, CP length and N under the different bandwidth configuration FFTAs shown in the table.

Conventional LTE small region search method is: at first, utilize narrowband low-pass filter to leach receiving the narrower frequency band that comprises the PSS/SSS signal in the data; Secondly, the position and the ID thereof that on time domain, whole reception data are slided respectively and are correlated with and discern the PSS signal at three possible PSS signals; Once more, detect the CP pattern of current system; At last, according to the position and the CP pattern of PSS signal, determine the position of SSS signal, and finish detection it.This implementation method often needs complicated narrowband low-pass filter design and more operand.And, exist under the situation of big frequency deviation, need the operand of several times of further increases to solve the frequency deviation problem, otherwise its detection performance can worsen rapidly.

Summary of the invention

Technical problem to be solved by this invention provides a kind of small region search method and device that is applied to long evolving system, to avoid complicated narrowband low-pass filter design, reduces operand.

For solving the problems of the technologies described above, it is as follows to the invention provides technical scheme:

A kind of small region search method that is applied to long evolving system comprises the steps:

A, obtain symbol regularly and the CP pattern information according to the repeat property of CP data;

B, according to symbol timing information, to the N in the OFDM symbol FFTIndividual data point is done fast fourier transform, obtains the frequency domain data of OFDM symbol, wherein, and N FFTLength for fast fourier transform;

C, according to primary and secondary synchronization signals pairing sub-carrier positions in frequency domain, from the frequency domain data of OFDM symbol, extract the first couple candidate detection signal;

D, according to the first couple candidate detection signal and known master sync signal sequence, detect the ID and the position thereof of the employed master sync signal of current area;

E, according to the position and the CP pattern information of master sync signal, obtain the second couple candidate detection signal at auxiliary synchronous signals place, according to the ID of the second couple candidate detection signal and the known employed auxiliary synchronous signals of auxiliary synchronous signals Sequence Detection current area, and obtain frame synchronization information according to the ID of auxiliary synchronous signals.

Above-mentioned small region search method, wherein, steps A comprises:

To receive data and himself delay N FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, obtain two groups of correlated serieses;

The peak value of two groups of correlated serieses relatively, peak value position that will be bigger be as the original position of symbol, and the pairing CP pattern of peak value that will be bigger is as CP pattern that current area adopted.

Above-mentioned small region search method, wherein, step D comprises:

The computing that the master sync signal that each is known and all first couple candidate detection signal are done conjugate multiplication and added up obtains three sequences;

Find out three maximal peak point in the sequence, with the ID of the pairing master sync signal of maximal peak point ID, with the position of the pairing character position of maximal peak point as master sync signal as the employed master sync signal of current area.

Above-mentioned small region search method, wherein, step e comprises:

The computing that the auxiliary synchronous signals that each is known and the second couple candidate detection signal are done conjugate multiplication and added up obtains the sequence that is made of 336 points;

Find out the peak point in the sequence that constitutes by 336 points, with the ID of the pairing auxiliary synchronous signals of this peak point ID as the employed auxiliary synchronous signals of current area;

Sequence according to this peak point correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, determines frame synchronization information.

Above-mentioned small region search method wherein, also comprises after the steps A:

Carry out frequency offset estimating and timing estimation;

Carry out frequency deviation adjustment and regularly adjustment according to frequency offset estimation result and timing estimation results.

A kind of cell search apparatus that is applied to long evolving system comprises:

Symbol timing and CP mode detector are used for obtaining symbol timing and CP pattern information according to the repeat property of CP data;

The FFT converter is used for according to symbol timing information, to the N in the OFDM symbol FFTIndividual data point is done fast fourier transform, obtains the frequency domain data of OFDM symbol, wherein, and N FFTLength for fast fourier transform;

The subcarrier withdrawal device is used for according to primary and secondary synchronization signals in the pairing sub-carrier positions of frequency domain, extracts the first couple candidate detection signal from the frequency domain data of OFDM symbol;

Master sync signal position and ID detector thereof are used for according to the first couple candidate detection signal and known master sync signal sequence, detect the ID and the position thereof of the employed master sync signal of current area;

Auxiliary synchronous signals ID and frame sync detector, be used for position and CP pattern information according to master sync signal, obtain the second couple candidate detection signal at auxiliary synchronous signals place, according to the ID of the second couple candidate detection signal and the known employed auxiliary synchronous signals of auxiliary synchronous signals Sequence Detection current area, and obtain frame synchronization information according to the ID of auxiliary synchronous signals.

Above-mentioned cell search apparatus, wherein, described symbol regularly is further used for the CP mode detector:

To receive data and himself delay N FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, obtain two groups of correlated serieses;

The peak value of two groups of correlated serieses relatively, peak value position that will be bigger be as the original position of symbol, and the pairing CP pattern of peak value that will be bigger is as CP pattern that current area adopted.

Above-mentioned cell search apparatus, wherein, described master sync signal position and ID detector thereof are further used for:

The computing that the master sync signal that each is known and all first couple candidate detection signal are done conjugate multiplication and added up obtains three sequences;

Find out three maximal peak point in the sequence, with the ID of the pairing master sync signal of maximal peak point ID, with the position of the pairing character position of maximal peak point as master sync signal as the employed master sync signal of current area.

Above-mentioned cell search apparatus, wherein, described auxiliary synchronous signals ID and frame sync detector are further used for:

The computing that the auxiliary synchronous signals that each is known and the second couple candidate detection signal are done conjugate multiplication and added up obtains the sequence that is made of 336 points;

Find out the peak point in the sequence that constitutes by 336 points, with the ID of the pairing auxiliary synchronous signals of this peak point ID as the employed auxiliary synchronous signals of current area;

Sequence according to this peak point correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, determines frame synchronization information.

Above-mentioned cell search apparatus wherein, also comprises:

Estimate synchronously and adjustment unit, be used to carry out frequency offset estimating and timing estimation, and carry out frequency deviation adjustment and regularly adjustment according to frequency offset estimation result and timing estimation results.

The present invention at first determines the original position and the CP pattern of symbol according to the repeat property of CP data, then, signal is transferred to frequency domain from time domain, and in frequency domain, detect the ID and the frame synchronization information of primary and secondary synchronization signals, like this, just avoid complicated narrowband low-pass filter design, reduced operand.

Description of drawings

Fig. 1 is the frequency domain distribution schematic diagram of PSS signal in specific OFDM symbol;

Fig. 2 is the position view of primary/secondary synchronizing signal in particular time-slot in the fdd mode;

Fig. 3 is the formation schematic diagram of OFDM symbol cyclic prefix;

Fig. 4 is the structural representation of the cell search apparatus that is applied to long evolving system of the embodiment of the invention;

Fig. 5 is the flow chart of the small region search method that is applied to long evolving system of the embodiment of the invention.

Embodiment

For making the purpose, technical solutions and advantages of the present invention clearer, describe the present invention below in conjunction with the accompanying drawings and the specific embodiments.

The present invention at first according to the repeat property of CP data finish symbol regularly with the detection of CP pattern; Regularly each symbol is carried out the FFT conversion according to symbol then, take out master sync signal and carry out the master sync signal detection, determine its position and ID in the data of the corresponding sub-carrier positions of frequency domain institute; According to the data of master sync signal position and CP pattern taking-up auxiliary synchronous signals position, finish detection at last to auxiliary synchronous signals ID.Meanwhile, can enable synchronous estimation certain (several) the individual particular moment in cell search process and adjust, improve its follow-up detection performance to guarantee frequency and time synchronized preferably.The enabling to enable in cell search process once of described synchronous estimation and adjustment also can be enabled repeatedly, perhaps in case to enable be continuous operation.Described certain specific moment can be finish symbol regularly with the detection of CP pattern after any time.

With reference to Fig. 4, the cell search apparatus that is applied to long evolving system of the embodiment of the invention mainly comprises: symbol timing and CP mode detector 10, FFT converter 20, subcarrier withdrawal device 30, master sync signal position and ID detector 40 thereof, auxiliary synchronous signals ID and frame sync detector 50, estimation and adjustment unit 60 synchronously.Below the function of above-mentioned each module is described in detail.

Symbol timing and CP mode detector 10

Symbol is original position and CP pattern informations of determining symbol according to the repeat property of CP data with CP mode detector 10 regularly.As the also exportable failure flags of a kind of preferred version, if detect failure, finish Cell searching, avoid flase drop to survey.

As embodiment, symbol regularly will receive data with CP mode detector 10 and himself postpones N FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, can obtain two groups of correlated serieses, the peak value that compares two groups of correlated serieses, bigger peak value position is the original position of symbol, and the big pairing CP pattern of peak value is the CP pattern that current area adopts.Determine the original position and the CP pattern (the CP pattern can be determined symbol lengths) of a certain symbol, just can determine the original position of all symbols, promptly obtained symbol timing information.If in the power of big peak value and its place sequence, compare with its average power with other points of certain intervals, less than certain threshold value, detect failure so, otherwise success.

FFT converter 20

FFT converter 20 takes out the N in each OFDM symbol according to symbol timing information FFTIndividual data point is done fast fourier transform to it, with data by spatial transform to frequency domain, obtain the frequency domain data of OFDM symbol.

Subcarrier withdrawal device 30

Subcarrier withdrawal device 30 is that a part of data pick-up in the frequency domain data of each OFDM symbol (being the output of FFT converter) is come out, the position of institute's extracted data is PSS/SSS signal pairing sub-carrier positions in OFDM symbol frequency domain, obviously this part should can both be extracted even can guarantee like this to exist than all PSS signals under the situation of big frequency deviation fully more than or equal to 62.For hereinafter statement is convenient this partial data is called the first couple candidate detection signal.

Master sync signal position and ID detector 40 thereof

Master sync signal position and ID detector 40 thereof are according to three known master sync signal sequences, in a plurality of first couple candidate detection signals that may comprise master sync signal, discern and detect, find out the ID of the employed master sync signal of current area and the position at place thereof.As the also exportable failure flags of a kind of preferred version.If detect failure, finish Cell searching, avoid flase drop to survey.

As embodiment, the computing that master sync signal that master sync signal position and ID detector 40 thereof can be known with each and the first all couple candidate detection signals are done conjugate multiplication and added up, can obtain three sequences like this, find out three maximal peak point in the sequence, the ID of the pairing master sync signal of this maximal peak point is the master sync signal ID of current area so; The pairing character position of this maximal peak point is the position of master sync signal.If the average power of other points in the power of big peak value and its place sequence is compared, less than certain threshold value, detect failure so, otherwise success.

Auxiliary synchronous signals ID and frame sync detector 50

Auxiliary synchronous signals ID and frame sync detector 50 are according to known master sync signal position and CP pattern information (can determine certain location relation between the primary and secondary synchronization signals by the CP pattern), find out the second couple candidate detection signal at auxiliary synchronous signals place.Utilize known 168 pairs of auxiliary synchronous signals and this couple candidate detection signal to finish the detection of auxiliary synchronous signals ID, and then find frame synchronization information, be i.e. the original position of each radio frames.As the also exportable failure flags of a kind of preferred version.If detect failure, finish Cell searching, avoid flase drop to survey.

As embodiment, the computing that auxiliary synchronous signals ID and frame sync detector 50 can be done 168 pairs of known auxiliary synchronous signals and the second couple candidate detection signal conjugate multiplication and add up, can obtain the sequence that constitutes by 336 points like this, find out the peak point in the sequence, the ID of the pairing auxiliary synchronous signals of this peak point is the employed auxiliary synchronous signals ID of current area so.Sequence according to this peak value correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, can determine frame synchronization information.Power as peak value in the infructescence is compared with the average power of other points, less than certain threshold value, detects failure so, otherwise success.

Estimate and adjustment unit 60 synchronously

Estimate to comprise with adjustment unit 60 estimation and adjustment (frequency offset estimator, frequency deviation adjuster) and the estimation regularly and the adjustment (timing estimator, timing adjuster) of frequency deviation synchronously, it can utilize CP data or detected primary and secondary synchronization signals to finish.Frequency deviation and estimation regularly can independently be finished respectively also and can finish together by uniting estimation.Obtain after frequency deviation and the estimation regularly, can adjust when the received signal next time, reduce the influence of frequency deviation and timing offset subsequent detection according to estimated result.

Estimate synchronously can to enable certain (several) the individual particular moment in cell search process,, improve its follow-up detection performance to guarantee frequency and time synchronized preferably with adjustment.The enabling to enable in cell search process once of described synchronous estimation and adjustment also can be enabled repeatedly, perhaps in case to enable be continuous operation.Described certain specific moment can be finish symbol regularly with the detection of CP pattern after any time.

About the synchronous estimation of ofdm system with adjust existing more prior art, for example, based on maximum likelihood timing and diviation combined estimation method, at this its concrete enforcement is not done and to be given unnecessary details.

Accordingly, the present invention also provides a kind of small region search method that is applied to long evolving system.

With reference to Fig. 5, the small region search method that is applied to long evolving system of the embodiment of the invention mainly comprises the steps:

Step 501: obtain symbol timing and CP pattern information according to the repeat property of CP data;

As the also exportable failure flags of a kind of preferred version,, avoid flase drop to survey if the failure of this step finishes Cell searching.

As embodiment, can data and himself delay N will be received FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, can obtain two groups of correlated serieses, the peak value that compares two groups of correlated serieses, bigger peak value position is the original position of symbol, and the big pairing CP pattern of peak value is the CP pattern that current area adopts.Determine the original position and the CP pattern (the CP pattern can be determined symbol lengths) of a certain symbol, just can determine the original position of all symbols, promptly obtained symbol timing information.If in the power of big peak value and its place sequence, compare with its average power with other points of certain intervals, less than certain threshold value, this step failure so, otherwise success.

Step 502: according to symbol timing information, to the N in the OFDM symbol FFTIndividual data point is done fast fourier transform, obtains the frequency domain data of OFDM symbol, wherein, and N FFTLength for fast fourier transform;

Step 503:, from the frequency domain data of OFDM symbol, extract the first couple candidate detection signal according to primary and secondary synchronization signals pairing sub-carrier positions in frequency domain;

A part of data pick-up in the frequency domain data of each OFDM symbol is come out, the position of institute's extracted data is PSS/SSS signal pairing sub-carrier positions in OFDM symbol frequency domain, obviously this part should can both be extracted even can guarantee like this to exist than all PSS signals under the situation of big frequency deviation fully more than or equal to 62.For hereinafter statement is convenient this partial data is called the first couple candidate detection signal.

Step 504:, detect the ID and the position thereof of the employed master sync signal of current area according to the first couple candidate detection signal and known master sync signal sequence;

As the also exportable failure flags of a kind of preferred version.If the failure of this step finishes Cell searching, avoid flase drop to survey.

As embodiment, the computing that master sync signal that can each is known and all first couple candidate detection signal are done conjugate multiplication and added up, can obtain three sequences like this, find out three maximal peak point in the sequence, the ID of the pairing master sync signal of this maximal peak point is the master sync signal ID of current area so; The pairing character position of this maximal peak point is the position of master sync signal.If the average power of other points in the power of big peak value and its place sequence is compared, less than certain threshold value, this step failure so, otherwise success.

Step 505: according to the position and the CP pattern information of master sync signal, obtain the second couple candidate detection signal at auxiliary synchronous signals place, according to the ID of the second couple candidate detection signal and the known employed auxiliary synchronous signals of auxiliary synchronous signals Sequence Detection current area, and obtain frame synchronization information according to the ID of auxiliary synchronous signals.

As the also exportable failure flags of a kind of preferred version.If the failure of this step finishes Cell searching, avoid flase drop to survey.

As embodiment, the computing that 168 pairs of known auxiliary synchronous signals and the second couple candidate detection signal can be done conjugate multiplication and added up, can obtain the sequence that constitutes by 336 points like this, find out the peak point in the sequence, the ID of the pairing auxiliary synchronous signals of this peak point is the employed auxiliary synchronous signals ID of current area so.Sequence according to this peak value correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, can determine frame synchronization information.Power as peak value in the infructescence is compared with the average power of other points, less than certain threshold value, and this step failure so, otherwise success.

Wherein, also can comprise after the step 501:

Carry out frequency offset estimating and timing estimation, carry out frequency deviation adjustment and regularly adjustment according to frequency offset estimation result and timing estimation results.

Can utilize CP data or detected primary and secondary synchronization signals to finish.Frequency deviation and estimation regularly can independently be finished respectively also and can finish together by uniting estimation.Obtain after frequency deviation and the estimation regularly, can adjust when the received signal next time, reduce the influence of frequency deviation and timing offset subsequent detection according to estimated result.

Estimate synchronously can to enable certain (several) the individual particular moment in cell search process,, improve its follow-up detection performance to guarantee frequency and time synchronized preferably with adjustment.The enabling to enable in cell search process once of described synchronous estimation and adjustment also can be enabled repeatedly, perhaps in case to enable be continuous operation.Described certain specific moment can be finish symbol regularly with the detection of CP pattern after any time.

About the synchronous estimation of ofdm system with adjust existing more prior art, for example, based on maximum likelihood timing and diviation combined estimation method, at this its concrete enforcement is not done and to be given unnecessary details.

Should be noted that at last, above embodiment is only unrestricted in order to technical scheme of the present invention to be described, those of ordinary skill in the art is to be understood that, can make amendment or be equal to replacement technical scheme of the present invention, and not breaking away from the spiritual scope of technical solution of the present invention, it all should be encompassed in the middle of the claim scope of the present invention.

Claims (10)

1. a small region search method that is applied to long evolving system is characterized in that, comprises the steps:
A, obtain symbol regularly and the CP pattern information according to the repeat property of cyclic prefix CP data;
B, according to symbol timing information, to the N in the orthogonal frequency division multiplex OFDM symbol FFTIndividual data point is done fast fourier transform, obtains the frequency domain data of OFDM symbol, wherein, and N FFTLength for fast fourier transform;
C, according to primary and secondary synchronization signals pairing sub-carrier positions in frequency domain, from the frequency domain data of OFDM symbol, extract the first couple candidate detection signal;
D, according to the first couple candidate detection signal and known master sync signal sequence, detect the ID and the position thereof of the employed master sync signal of current area;
E, according to the position and the CP pattern information of master sync signal, obtain the second couple candidate detection signal at auxiliary synchronous signals place, according to the ID of the second couple candidate detection signal and the known employed auxiliary synchronous signals of auxiliary synchronous signals Sequence Detection current area, and obtain frame synchronization information according to the ID of auxiliary synchronous signals.
2. small region search method as claimed in claim 1 is characterized in that steps A comprises:
To receive data and himself delay N FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, obtain two groups of correlated serieses;
The peak value of two groups of correlated serieses relatively, peak value position that will be bigger be as the original position of symbol, and the pairing CP pattern of peak value that will be bigger is as CP pattern that current area adopted.
3. small region search method as claimed in claim 1 is characterized in that step D comprises:
The computing that the master sync signal that each is known and all first couple candidate detection signal are done conjugate multiplication and added up obtains three sequences;
Find out three maximal peak point in the sequence, with the ID of the pairing master sync signal of maximal peak point ID, with the position of the pairing character position of maximal peak point as master sync signal as the employed master sync signal of current area.
4. small region search method as claimed in claim 1 is characterized in that step e comprises:
The computing that the auxiliary synchronous signals that each is known and the second couple candidate detection signal are done conjugate multiplication and added up obtains the sequence that is made of 336 points;
Find out the peak point in the sequence that constitutes by 336 points, with the ID of the pairing auxiliary synchronous signals of this peak point ID as the employed auxiliary synchronous signals of current area;
Sequence according to this peak point correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, determines frame synchronization information.
5. small region search method as claimed in claim 1 is characterized in that, also comprises after the steps A:
Carry out frequency offset estimating and timing estimation;
Carry out frequency deviation adjustment and regularly adjustment according to frequency offset estimation result and timing estimation results.
6. a cell search apparatus that is applied to long evolving system is characterized in that, comprising:
Symbol timing and CP mode detector are used for obtaining symbol timing and CP pattern information according to the repeat property of CP data;
The FFT converter is used for according to symbol timing information, to the N in the OFDM symbol FFTIndividual data point is done fast fourier transform, obtains the frequency domain data of OFDM symbol, wherein, and N FFTLength for fast fourier transform;
The subcarrier withdrawal device is used for according to primary and secondary synchronization signals in the pairing sub-carrier positions of frequency domain, extracts the first couple candidate detection signal from the frequency domain data of OFDM symbol;
Master sync signal position and ID detector thereof are used for according to the first couple candidate detection signal and known master sync signal sequence, detect the ID and the position thereof of the employed master sync signal of current area;
Auxiliary synchronous signals ID and frame sync detector, be used for position and CP pattern information according to master sync signal, obtain the second couple candidate detection signal at auxiliary synchronous signals place, according to the ID of the second couple candidate detection signal and the known employed auxiliary synchronous signals of auxiliary synchronous signals Sequence Detection current area, and obtain frame synchronization information according to the ID of auxiliary synchronous signals.
7. cell search apparatus as claimed in claim 6 is characterized in that, described symbol regularly is further used for the CP mode detector:
To receive data and himself delay N FFTData carry out related operation based on two kinds of CP length of normal mode and mode of extension respectively, obtain two groups of correlated serieses;
The peak value of two groups of correlated serieses relatively, peak value position that will be bigger be as the original position of symbol, and the pairing CP pattern of peak value that will be bigger is as CP pattern that current area adopted.
8. cell search apparatus as claimed in claim 6 is characterized in that, described master sync signal position and ID detector thereof are further used for:
The computing that the master sync signal that each is known and all first couple candidate detection signal are done conjugate multiplication and added up obtains three sequences;
Find out three maximal peak point in the sequence, with the ID of the pairing master sync signal of maximal peak point ID, with the position of the pairing character position of maximal peak point as master sync signal as the employed master sync signal of current area.
9. cell search apparatus as claimed in claim 6 is characterized in that, described auxiliary synchronous signals ID and frame sync detector are further used for:
The computing that the auxiliary synchronous signals that each is known and the second couple candidate detection signal are done conjugate multiplication and added up obtains the sequence that is made of 336 points;
Find out the peak point in the sequence that constitutes by 336 points, with the ID of the pairing auxiliary synchronous signals of this peak point ID as the employed auxiliary synchronous signals of current area;
Sequence according to this peak point correspondence is first auxiliary synchronous signals or second auxiliary synchronous signals in the frame, determines frame synchronization information.
10. cell search apparatus as claimed in claim 6 is characterized in that, also comprises:
Estimate synchronously and adjustment unit, be used to carry out frequency offset estimating and timing estimation, and carry out frequency deviation adjustment and regularly adjustment according to frequency offset estimation result and timing estimation results.
CN2009102418266A 2009-12-09 2009-12-09 District searching method and d device applied to long-period evolution system CN101719890B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN2009102418266A CN101719890B (en) 2009-12-09 2009-12-09 District searching method and d device applied to long-period evolution system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN2009102418266A CN101719890B (en) 2009-12-09 2009-12-09 District searching method and d device applied to long-period evolution system

Publications (2)

Publication Number Publication Date
CN101719890A true CN101719890A (en) 2010-06-02
CN101719890B CN101719890B (en) 2012-06-27

Family

ID=42434407

Family Applications (1)

Application Number Title Priority Date Filing Date
CN2009102418266A CN101719890B (en) 2009-12-09 2009-12-09 District searching method and d device applied to long-period evolution system

Country Status (1)

Country Link
CN (1) CN101719890B (en)

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101895982A (en) * 2010-07-12 2010-11-24 合肥东芯通信股份有限公司 Downlink synchronous method, equipment and system applied to long-term evolution
CN102223696A (en) * 2011-06-17 2011-10-19 电子科技大学 Cell searching method in LTE (long term evolution) system
CN102300286A (en) * 2010-06-23 2011-12-28 富士通株式会社 Method and device for obtaining auxiliary synchronization information and method and device for searching adjacent cells
CN102387582A (en) * 2010-08-31 2012-03-21 联芯科技有限公司 Detection method and device for cell group numbers of secondary synchronization sequences of LTE (long term evolution) system
CN102421114A (en) * 2011-11-30 2012-04-18 合肥东芯通信股份有限公司 Device and method for searching same-frequency neighbor cells of long term evolution (LTE) system
CN103379077A (en) * 2012-04-27 2013-10-30 株式会社Ntt都科摩 Frame synchronization and symbol synchronization method and device in wireless communication system
CN105830375A (en) * 2013-12-20 2016-08-03 株式会社秀利得 Lte Frame Synchronization Detection Method And Apparatus And Relay Apparatus Applying Same
CN108141834A (en) * 2015-07-27 2018-06-08 瑞典爱立信有限公司 Narrowband LTE cell searchings
US10659273B2 (en) 2015-11-04 2020-05-19 Zte Corporation Synchronization signal transmission and detection method, transmission end, receiving end, and storage medium

Cited By (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102300286A (en) * 2010-06-23 2011-12-28 富士通株式会社 Method and device for obtaining auxiliary synchronization information and method and device for searching adjacent cells
CN101895982A (en) * 2010-07-12 2010-11-24 合肥东芯通信股份有限公司 Downlink synchronous method, equipment and system applied to long-term evolution
CN101895982B (en) * 2010-07-12 2012-12-19 合肥东芯通信股份有限公司 Downlink synchronous method, equipment and system applied to long-term evolution
CN102387582A (en) * 2010-08-31 2012-03-21 联芯科技有限公司 Detection method and device for cell group numbers of secondary synchronization sequences of LTE (long term evolution) system
CN102387582B (en) * 2010-08-31 2014-11-26 联芯科技有限公司 Detection method and device for cell group numbers of secondary synchronization sequences of LTE (long term evolution) system
CN102223696A (en) * 2011-06-17 2011-10-19 电子科技大学 Cell searching method in LTE (long term evolution) system
CN102223696B (en) * 2011-06-17 2013-09-25 电子科技大学 Cell searching method in LTE (long term evolution) system
CN102421114B (en) * 2011-11-30 2014-04-23 合肥东芯通信股份有限公司 Device and method for searching same-frequency neighbor cells of long term evolution (LTE) system
CN102421114A (en) * 2011-11-30 2012-04-18 合肥东芯通信股份有限公司 Device and method for searching same-frequency neighbor cells of long term evolution (LTE) system
CN103379077A (en) * 2012-04-27 2013-10-30 株式会社Ntt都科摩 Frame synchronization and symbol synchronization method and device in wireless communication system
CN105830375A (en) * 2013-12-20 2016-08-03 株式会社秀利得 Lte Frame Synchronization Detection Method And Apparatus And Relay Apparatus Applying Same
CN108141834A (en) * 2015-07-27 2018-06-08 瑞典爱立信有限公司 Narrowband LTE cell searchings
US10659273B2 (en) 2015-11-04 2020-05-19 Zte Corporation Synchronization signal transmission and detection method, transmission end, receiving end, and storage medium

Also Published As

Publication number Publication date
CN101719890B (en) 2012-06-27

Similar Documents

Publication Publication Date Title
US20190350012A1 (en) Initial Access Channel for Scalable Wireless Mobile Communication Networks
JP6080050B2 (en) Program for establishing a synchronization signal in a communication system
US20190239249A1 (en) Processing of random access preamble sequences
CN103548291B (en) The cell search process of heterogeneous network
EP2752061B1 (en) Time and frequency synchronization
EP2437453B1 (en) Secondary synchronization signal detection method and device
US9241362B2 (en) Method and apparatus for transmitting data between wireless devices in wireless communication system
US8331331B2 (en) Method and apparatus for determining cell timing in a wireless communication system
US8014311B2 (en) Signal measurements based on sync signals
US7924808B2 (en) Method of transmitting synchronization signal in wireless communication system
US8447005B2 (en) Frequency synchronization methods and apparatus
JP4339362B2 (en) Method and apparatus for detecting cells in an orthogonal frequency division multiple access system
US9337994B2 (en) Method, receiver and system for signal synchronization
CN101388723B (en) Radio communication timing synchronization method, cell searching method and system
EP1424821B1 (en) Symbol timing for MIMO OFDM and other wireless communication systems
US7990932B2 (en) Apparatus, method and computer program product providing initial cell acquisition and pilot sequence detection
KR100827064B1 (en) Method and Apparatus for transmitting synchronization signal in OFDM based cellular communication systems
CN100518159C (en) TDS-OFDM receiver and signal processing method thereof
CN101849397B (en) Channel estimation for synchronized cells in a cellular communication system
US7372893B2 (en) Device and method for compensating for phase distortion in base station of OFDMA-based cellular system
CN101295999B (en) Detection method for accidental precursor access
US8929197B2 (en) Method and system for an OFDM joint training and frequency tracking system
CN102148785B (en) Methods and devices for detecting main synchronous signal and generating sequence in LTE (Long Term Evolution) system
CN101267226B (en) An information sending method for auxiliary synchronization channel and cell search method
CN101009513B (en) Cell synchronization method and initial cell searching method for broadband time-division dual-duplex cellular system

Legal Events

Date Code Title Description
PB01 Publication
C06 Publication
SE01 Entry into force of request for substantive examination
C10 Entry into substantive examination
GR01 Patent grant
C14 Grant of patent or utility model
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20120627

Termination date: 20181209

CF01 Termination of patent right due to non-payment of annual fee