WO2011157088A1

WO2011157088A1 - Method and apparatus for confirming downlink synchronous code of single-sampled data in td-scdma

Info

Publication number: WO2011157088A1
Application number: PCT/CN2011/073833
Authority: WO
Inventors: 徐鑫昌; 程健
Original assignee: 中兴通讯股份有限公司
Priority date: 2010-06-13
Filing date: 2011-05-09
Publication date: 2011-12-22
Also published as: CN102281082B; CN102281082A

Abstract

A method and an apparatus for confirming downlink synchronous code of single-sampled data in TD-SCDMA are provided in the present invention. The method for confirming downlink synchronous code includes: performing sliding correlation calculation on the received sub-frame data and the 32 local downlink synchronous codes, and obtaining 32 sets of correlation values; computing the power value of each correlation value in said 32 sets of correlation values, and obtaining 32 sets of correlation power values; processing each set of correlation power values in said 32 sets of correlation power values respectively, and obtaining corresponding correlation peak values; reserving the correlation peak values that are greater than the first preset threshold from the obtained correlation peak values, and recording the corresponding downlink synchronous code and its location. The method and apparatus for confirming the downlink synchronous code in TD-SCDMA of the present invention reduce computational complexity and save hardware resources as well as guaranteeing an effective cell searching performance, and can well adapt to the cell searching of the TD-SCDMA system.

Description

Downlink synchronization code confirmation method and device for single sampling data in TD-SCDMA

The present invention relates to the field of mobile communications, and in particular, to a downlink synchronization code confirmation method and apparatus for single-sample data in Time Division-Synchronous Code Division Multiple Access (TD-SCDMA). Background technique

In the TD-SCDMA mobile communication system, initial cell search is a very critical process. After the user terminal (UE) is powered on, it must search for a suitable cell as soon as possible, and then obtain more detailed information of the cell or information of the neighboring cell, so as to log in to the cell and use the network service, such as listening for a page or initiating a call.

As shown in FIG. 1 , the initial cell search process mainly includes: searching for a downlink pilot time slot (DwPTS, Downlink Pilot Time Slot), a downlink synchronization code (SYNC_DL, Synchronous Code of Downlink), a scrambling code, and a basic training sequence (midamble). Code identification, control of multiframe synchronization, read broadcast channel (BCH, Broadcast Channel) „ where SYNC_DL acknowledges mainly based on good autocorrelation and cross-correlation of the code sequence, resulting in sharp peaks. However, if downlink synchronization tracking (DST) , Downlink Synchronous Track) Inaccurate adjustment, there may be a large deviation of the sample, the correlation peak of SYNC_DL is not obvious, so as to reduce the success rate of cell search. In the prior art, in order to improve the success rate of cell search, Store multiple times of sample data, and find the maximum correlation peak after multiple sliding correlations.

Although the above method can improve the success rate of cell search to a certain extent, it requires a large amount of hardware resources, and needs to be subjected to multiple sliding correlations, and the calculation amount is relatively large. Summary of the invention

The main object of the present invention is to provide a downlink synchronization code acknowledgment method and apparatus for singular data in TD-SCDMA, which aims to ensure cell search performance while saving hardware resources.

The invention provides a downlink synchronization code confirmation method for single sample data in TD-SCDM A, which comprises the following steps:

Performing sliding correlation calculation on the received subframe data and the local 32 downlink synchronization codes to obtain 32 sets of correlation values;

Calculating energy values of each of the 32 sets of correlation values, obtaining 32 sets of correlation energy values; respectively processing the correlation energy values of each of the 32 sets of correlation energy values, and obtaining corresponding correlation peaks;

The correlation peaks of the obtained correlation peaks larger than the first preset threshold are reserved, and the corresponding downlink synchronization codes and the positions of the downlink synchronization codes are recorded.

Preferably, the foregoing respectively processes the correlation energy values of each of the 32 sets of related energy values, and obtains corresponding correlation peaks, including:

Comparing the correlation energy values of adjacent ones of the largest correlation energy values of the set of the related energy values with the second preset threshold respectively, and recording the obtained products as the first comparison energy value and the second comparison respectively Energy value;

Comparing the maximum correlation energy value with the first comparison energy value and the second comparison energy value, respectively;

Corresponding processing is performed according to the result of the comparison to obtain a correlation peak.

Preferably, the foregoing processing is performed according to the result of the comparison to obtain a correlation peak, which is:

When the maximum correlation energy value is greater than or equal to the first comparison energy value and the second comparison energy value, the correlation value corresponding to the maximum correlation energy value is recorded as a correlation peak;

The maximum correlation energy value is less than the first comparison energy value or the second comparison energy value And performing a shift addition calculation on each correlation value corresponding to the maximum correlation energy value, obtaining a processed correlation value, and calculating a correlation energy value of each correlation value after the processing; The correlation value corresponding to the largest correlation energy value among the correlation energy values of the correlation values of each correlation value is recorded as a correlation peak.

Preferably, the number of correlation peaks greater than the first preset threshold among the correlation peaks obtained by the above reservation is less than or equal to 8.

Preferably, the received subframe data is data in a range of one subframe or single-sample data in a determined range obtained by detecting a feature window in one subframe.

The present invention further provides a downlink synchronization code confirming apparatus for single-sample data in TD-SCDMA, the apparatus comprising: a correlation value calculation module, a correlation energy value calculation module, a correlation peak calculation module, and a downlink synchronization code recording module; ,

a correlation value calculation module, configured to perform sliding correlation calculation on the received subframe data and the local 32 downlink synchronization codes, to obtain 32 sets of correlation values;

a correlation energy value calculation module, configured to calculate an energy value of each of the 32 sets of correlation values obtained by the correlation value calculation module, and obtain 32 sets of correlation energy values;

The correlation peak calculation module respectively processes the correlation energy values of each of the 32 sets of correlation energy values obtained by the correlation energy value calculation module, and obtains corresponding correlation peaks;

The downlink synchronization code recording module retains a correlation peak greater than the first preset threshold among the correlation peaks obtained by the correlation peak calculation module, and records the corresponding downlink synchronization code and its position.

Preferably, the correlation peak calculation module includes: a comparison energy value acquisition unit, a comparison unit, and a processing unit; wherein

a comparison energy value obtaining unit, configured to multiply the correlation energy values of adjacent ones of the largest correlation energy values of the set of related energy values obtained by the correlation value calculation module by a second preset threshold, and obtain The product of the first comparison energy value and the second comparison energy value are respectively recorded;

a comparing unit, configured to obtain the maximum correlation energy value and the comparison energy value respectively Comparing the first comparison energy value and the second comparison energy value obtained by the unit;

And a processing unit, configured to perform corresponding processing according to the comparison result of the comparing unit to obtain a correlation peak.

Preferably, the processing unit includes: a first processing subunit, a shift addition computing subunit, and a second processing subunit; wherein

a first processing subunit, configured to record a correlation value corresponding to the largest correlation energy value as a correlation peak when the maximum correlation energy value is greater than or equal to the first comparison energy value and the second comparison energy value;

a shift addition calculation subunit, configured to: when the maximum correlation energy value is smaller than the first comparison energy value or the second comparison energy value, compare each correlation value corresponding to the maximum correlation energy value Performing a shift addition calculation to obtain a processed correlation value, and calculating a correlation energy value of each correlation value after processing;

The second processing sub-unit is configured to record, as the correlation peak, a correlation value corresponding to the largest correlation energy value among the correlation energy values of the processed correlation values calculated by the shift addition calculation sub-unit.

Preferably, the downlink synchronization code recording module retains less than or equal to 8 correlation peaks greater than the first preset threshold.

Preferably, the subframe data received by the correlation value calculation module is data within a sub-frame range or single-sample data within a determined range obtained by detecting the feature window in one sub-frame.

The method and device for confirming the downlink synchronization code of the single sample data in the TD-SCDM A of the present invention reduces the calculation amount and saves the hardware resources while ensuring the effective cell search performance, and can well adapt to the TD-SCDMA system. Cell search. DRAWINGS

1 is a schematic diagram of a cell initial search process in a prior art TD-SCDMA;

2 is a schematic flow chart of an embodiment of a method for confirming a downlink synchronization code of a single data in TD-SCDMA according to the present invention; 3 is a schematic diagram of a frame structure of a TD-SCDM A of the present invention;

4 is a schematic flow chart of separately processing each group of related energy values in the above embodiment, and obtaining corresponding correlation peaks;

Fig. 5 is a schematic diagram of correlation peaks before and after shift addition processing in the absence of sample deviation; Fig. 6 is a diagram showing correlation peaks before and after shift addition processing in the case of l/2chip sample deviation;

7 is a schematic diagram showing the structure of an embodiment of a downlink synchronization code confirming apparatus for singular data in TD-SCDMA according to the present invention;

8 is a schematic structural diagram of a correlation peak calculation module in the embodiment shown in FIG. 7. FIG. 9 is a schematic structural diagram of a processing unit in the embodiment shown in FIG. detailed description

The technical solutions of the present invention are further described below in conjunction with the drawings and specific embodiments. It is understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

In order to solve the problem that the Sync_DL confirmation in the cell search process is easily affected by the sample deviation, and the cell search performance is lost, the prior art reduces performance loss by storing multiple data samples and performing multiple sliding correlations. Will increase the overhead of the hardware. In the present invention, only a single data is stored, which not only ensures the performance of the cell search, but also saves hardware resources and multiple related operations.

2 is a flow chart showing an embodiment of a method for confirming a downlink data synchronization code of a single sample data in the TD-SCDM A of the present invention.

The method for confirming the downlink synchronization code of the single sample data in the TD-SCDM A in this embodiment may mainly include the following steps: Off calculation, and obtaining 32 sets of correlation values; The received sub-frame data is data within a sub-frame range or single-sample data within a determined range obtained by detecting the feature window in one sub-frame. As shown in FIG. 3, which is a schematic diagram of a subframe structure of the TD-SCDMA, the subframe of the TD-SCDM A includes a time slot 0 (TS0, Time slot 0), a guard time slot (GP, Guard Period), a Sync_DL, and an uplink synchronization code. (Sync_UL, Synchronous Code of Uplink).

In practical applications, the method of establishing a "feature window" by using the power shape of the received signal may first perform coarse synchronization to obtain the approximate position of the DwPTS, and then perform sliding correlation calculation on the subframe data. Of course, the received subframe data may be directly subjected to sliding correlation calculation with the local 32 downlink synchronization codes without performing any processing on the received subframe data. However, in contrast, data that has undergone coarse synchronization via the "feature window" requires fewer scan-related calculations.

Step S11: Calculate energy values of each of the 32 sets of correlation values, and obtain 32 sets of related energy values;

Step S12: processing the correlation energy values of each group separately, and obtaining corresponding correlation peaks;

Each set of correlation energy of the 32 sets of correlation energy values obtained in step S11 is processed, and a corresponding correlation peak is obtained.

Step S13: Keep correlation peaks larger than the first preset threshold, and record corresponding downlink synchronization codes and locations of the downlink synchronization codes.

The first preset threshold is set in advance, and the first preset threshold may be set according to requirements of the end user or system performance, and is not limited herein.

A correlation peak greater than the first preset threshold is reserved, and the corresponding downlink synchronization code and its position are recorded. Based on subsequent scrambling codes and basic training sequence codes, the correlation peaks are generally retained at a maximum of eight. If the retained correlation peak is 0, then return to step S10; if the retained correlation peak value is greater than 8, the maximum 8 correlation peaks are retained.

Referring to FIG. 4, the processing of step S12 may further include the following steps: Step S121, multiplying the correlation energy values on the adjacent sides of the largest correlation energy value Pmax of the 32 sets of correlation energy values by the second preset threshold, and recording the obtained products as the first comparison energy value P1 and Second comparison energy value P2;

Step S122: Comparing the maximum correlation energy value Pmax with the first comparison energy value P1 and the second comparison energy value P2, respectively, determining whether the maximum correlation energy value Pmax is greater than the first comparison energy value P1, and the second Comparing the energy value P2, if yes, go to step S123, if not, go to step S124;

Step S123: Record the correlation value corresponding to the largest correlation energy value Pmax as the correlation peak value; Step S124, perform shift addition calculation on each correlation value of the same group, obtain the processed correlation value, and calculate the correlation value after the processing. Related energy value;

Here, the same group refers to a correlation value group in which the correlation value corresponding to the largest correlation energy value Pmax is located.

Step S125: Record the correlation value corresponding to the maximum correlation energy value Pmax' among the correlation energy values of the correlation values after the processing as the correlation peak.

The following is a detailed description of the process of performing the downlink synchronization code checking operation on the data obtained by the feature window detection.

The feature window detection in the present invention uses a single data sample and has a length of 128 chips (chip). The data obtained by the feature window detection includes 64 chips of the downlink synchronization code sequence and data of 32 chips before and after.

(1) Sliding correlation calculation between the data of 128 chipss and the local 32 downlink synchronization codes to obtain 32 sets of correlation values;

In the TD-SCDMA of the present invention, there are 32 downlink synchronization codes, and each downlink synchronization code has a length of 64 chips. The downlink synchronization code is separately recorded as Sync_DL(0), Sync_DL(1), Sync_DL(2) ... Sync_DL(31), and the data of length 128 chips is respectively subjected to sliding correlation calculation with 32 downlink synchronization codes to obtain 32. Group related values. Among them, each group includes 64 correlation values. (2) Calculate the energy of the correlation values in each group separately, and obtain 32 sets of correlation energy values; calculate the energy of 64 correlation values of each of the 32 groups of correlation values, and obtain the corresponding 32 sets of correlation energy values.

(3) Processing each group of related energy values separately, taking the processing of the first group of related energy values as an example:

A. Multiplying the correlation energy values of the adjacent sides of the largest correlation energy value by the second preset threshold, respectively, and the obtained products are respectively recorded as the first comparison energy value and the second comparison energy value;

The maximum correlation energy value is recorded as Pmax, and the second preset threshold is preferably 6.25. The two correlation energy values adjacent to Pmax are selected and multiplied by the second preset threshold to obtain a first comparison energy value Pl and a second comparison energy value P2, respectively.

B. Comparing the maximum correlation energy values with the first comparison energy value and the second comparison energy value;

The maximum correlation energy value Pmax is compared with the first comparison energy value P1 and the second comparison energy value P2. When Pmax>Pl and Pmax>P2, the correlation value corresponding to the largest correlation energy value Pmax is recorded as the correlation peak. Otherwise, the 64 correlation values of the group corresponding to the correlation value of the largest correlation energy value Pmax are shifted forward or backward by 1 bit, and the original 64 correlation values are added to the true values of the shifted correlation values to obtain The 64 correlation values after processing, and calculate the correlation energy values of the 64 correlation values after processing. Finally, the correlation value of the maximum correlation energy value Pmax' among the correlation energy values obtained after the corresponding processing is recorded as the correlation peak.

(4) Retaining the correlation peak greater than the first preset threshold, and recording the corresponding downlink synchronization code and its position.

After the received data of 128 chipss is correlated with the local 32 downlink synchronization codes and the corresponding 32 correlation peaks are obtained, the 32 correlation peaks are compared with the first preset threshold, and the retention is greater than the first A correlation peak of a preset threshold is recorded, and a corresponding downlink synchronization code and its position are recorded for subsequent scrambling code and identification of the basic training sequence code. Reserved greater than the first preset gate The number of limited correlation peaks is preferably eight. If the retained correlation peak is 0, then the feature window detection is returned, and the new data is re-accepted; if the retained correlation peak is greater than 8, the maximum 8 correlation peaks are retained.

Fig. 5 is a schematic diagram showing correlation peaks before and after shift addition processing in the absence of sample deviation.

Referring to Fig. 5A, in the case of no sample deviation, only one correlation peak obtained after the sliding correlation calculation is more prominent. Referring to FIG. 5B, in the case of no sample deviation, after the sliding correlation calculation, the correlation peak obtained after the shift addition processing is more prominent, and the signal-to-noise ratio relative shift true value is added. The previous signal to noise ratio is lower. Therefore, in the case of no sample deviation, no shift addition processing is required.

Fig. 6 is a diagram showing the correlation peaks before and after the shift addition processing in the case of the l/2chip sample deviation.

Referring to Fig. 6A, in the case of the l/2chip sample deviation, the correlation peaks obtained by only the sliding correlation calculation are more prominent. Referring to Fig. 6B, in the case of the l/2chip sample deviation, the correlation peak obtained by the shift correlation process and then the shift correlation process is more prominent. Therefore, in the case of l/2chip sample deviation, the correlation peak obtained after the shift addition process can reach the correlation peak obtained when there is no sample deviation.

The downlink synchronization code confirmation method for the single sample data in the TD-SCDMA of the invention reduces the calculation amount and saves the hardware resources while ensuring the effective cell search performance, and can well adapt to the cell of the TD-SCDM A system. search for.

Fig. 7 is a block diagram showing an embodiment of a downlink synchronization code confirming apparatus for singular data in TD-SCDMA according to the present invention.

The device for verifying the downlink synchronization code of the singular data in the TD-SCDMA of the present embodiment includes: a correlation value calculation module 10, configured to perform sliding correlation calculation between the received subframe data and the local 32 downlink synchronization codes, to obtain 32 groups. Related value

The correlation energy value calculation module 20 is configured to calculate 32 groups obtained by the correlation value calculation module 10 The energy value of each correlation value in the correlation value, obtaining 32 sets of related energy values;

The correlation peak calculation module 30 respectively processes the correlation energy values of each of the 32 sets of correlation energy values obtained by the correlation energy value calculation module 20, and obtains corresponding correlation peaks; the downlink synchronization code recording module 40 retains correlation The correlation peak obtained by the peak calculation module 30 is greater than the correlation peak of the first preset threshold, and records the corresponding downlink synchronization code and the location of the downlink synchronization code.

The sub-frame data received in the correlation value calculation module 10 is data within a sub-frame range or data within a determined range obtained by detecting a feature window in one sub-frame. The method of establishing the "feature window" by using the power shape of the received signal first performs coarse synchronization to obtain the approximate position of the DwPTS, and then performs sliding correlation calculation on the sub-frame data. Alternatively, the received subframe data may be directly subjected to sliding correlation calculation with the local N downlink synchronization codes without performing any processing on the received subframe data. However, in contrast, data that has been coarsely synchronized via the "feature window" requires fewer scan-related calculations.

The first preset threshold in the downlink synchronization code recording module 40 can be set according to the requirements of the end user or the performance of the system, and is not limited herein.

A correlation peak greater than the first preset threshold is reserved, and the corresponding downlink synchronization code and its position are recorded. Based on subsequent scrambling codes and basic training sequence codes, the correlation peaks are generally retained at a maximum of eight. If the retained correlation peak is 0, the correlation value calculation module 10 re-receives the new data and performs the calculation of the correlation value; if the retained correlation peak is greater than 8, the maximum 8 correlation peaks are retained.

Referring to FIG. 8, the correlation peak calculation module 30 may include: a comparison energy value acquisition unit 31, a comparison unit 32, and a processing unit 33;

The comparison energy value obtaining unit 31 is configured to multiply the correlation energy values of the adjacent sides of the largest correlation energy value by the second preset threshold respectively, and record the obtained products as the first comparison energy value, respectively. Second, compare energy values; The comparing unit 32 is configured to compare the maximum correlation energy value with the first comparison energy value and the second comparison energy value obtained by the comparison energy value obtaining unit 31, respectively;

The processing unit 33 is configured to perform corresponding processing according to the comparison result of the comparing unit 32 to obtain a correlation peak.

And when the maximum correlation energy value is greater than or equal to the first comparison energy value and the second comparison energy value, the correlation value corresponding to the maximum correlation energy value is recorded as a correlation peak.

Referring to FIG. 9, the processing unit 33 may include:

The first processing sub-unit 331 is configured to record the correlation value corresponding to the maximum correlation energy value as a correlation peak when the maximum correlation energy value is greater than or equal to the first comparison energy value and the second comparison energy value ;

The shift addition calculation sub-unit 332 is configured to: when the maximum correlation energy value is smaller than the first comparison energy value or the second comparison energy value, correlate the correlation values corresponding to the maximum correlation energy value The value is subjected to shift addition calculation to obtain the processed correlation value, and the correlation energy value of each correlation value after processing is calculated;

The second processing sub-unit 333 is configured to record, as the correlation peak, a correlation value corresponding to the largest correlation energy value among the correlation energy values of the processed correlation values obtained by the shift addition calculation sub-unit 332.

The downlink synchronization code confirming apparatus for singular data in the TD-SCDMA of the invention reduces the calculation amount and saves hardware resources while ensuring effective cell search performance, and can well adapt to the cell of the TD-SCDM A system. search for.

The above description is only a preferred embodiment of the present invention, and is not intended to limit the scope of the patents. The equivalent structure or equivalent process transformations made by the description of the present invention and the drawings are directly or indirectly applied to other related technical fields. The same is included in the scope of patent protection of the present invention.

Claims

Claim

A downlink synchronization code acknowledgment method for singular data in time division synchronous code division multiple access (TD-SCDMA), characterized in that the method comprises the following steps:

2. The method for confirming a downlink synchronization code for singular data in TD-SCDMA according to claim 1, wherein said processing the correlation energy value of each of said 32 sets of correlation energy values respectively And get the corresponding correlation peaks, including:

The method for confirming the downlink synchronization code of the singular data in the TD-SCDMA according to claim 2, wherein the processing is performed according to the result of the comparison to obtain a correlation peak, which is:

The maximum correlation energy value is less than the first comparison energy value or the second comparison energy value And performing a shift addition calculation on each correlation value corresponding to the maximum correlation energy value, obtaining a processed correlation value, and calculating a correlation energy value of each correlation value after the processing; The correlation value corresponding to the largest correlation energy value among the correlation energy values of the correlation values is recorded as the correlation peak.

The method for confirming the downlink synchronization code of the singular data in the TD-SCDMA according to claim 2, wherein the number of correlation peaks greater than the first preset threshold among the correlation peaks obtained by the reservation is less than Or equal to 8.

The method for confirming the downlink synchronization code of the singular data in the TD-SCDMA according to claim 1, wherein the received subframe data is data within one subframe or one intra-frame feature. The haplotype data within the determined range obtained after the window is detected.

6. A downlink synchronization code confirming apparatus for singular data in TD-SCDMA, characterized in that: the apparatus comprises: a correlation value calculation module, a correlation energy value calculation module, a correlation peak calculation module, and a downlink synchronization code recording module. ; among them,

The device for verifying the downlink synchronization code of the singular data in the TD-SCDMA according to claim 6, wherein the correlation peak calculation module comprises: a comparison energy value acquisition unit, a comparison unit, and a processing unit; among them,

a comparison energy value obtaining unit, configured to obtain a set of correlations obtained by the correlation value calculation module The correlation energy values adjacent to the two sides of the largest correlation energy value of the energy value are respectively multiplied by the second preset threshold, and the obtained products are respectively recorded as the first comparison energy value and the second comparison energy value;

a comparison unit, configured to compare the maximum correlation energy value with a first comparison energy value and a second comparison energy value;

The processing unit is configured to perform corresponding processing according to the result of the comparison to obtain a correlation peak.

The device for verifying the downlink synchronization code of the singular data in the TD-SCDMA according to claim 7, wherein the processing unit comprises: a first processing subunit, a shift addition calculation subunit, and a Two processing subunits; wherein

a first processing subunit, configured to record, when the maximum correlation energy value is greater than or equal to the first comparison energy value and the second comparison energy value, a correlation value corresponding to the maximum correlation energy value Peak value

The device of claim 7, wherein the downlink synchronization code recording module retains a number of correlation peaks larger than the first preset threshold, and is smaller than the number of correlation peaks that are greater than the first preset threshold. Or equal to 8.

The device for verifying the downlink synchronization code of the singular data in the TD-SCDMA according to claim 6, wherein the subframe data received by the correlation value calculation module is data within a subframe range, or The haplotype data within the determined range obtained by the feature window detection in one sub-frame.