Wireless synchronization method, apparatus and device, and storage medium

Abstract

The embodiment of the invention provides a wireless synchronization method and device, equipment and a storage medium, and the method comprises the steps: carrying out the segmentation extraction of an up-sampled wireless signal, and when the segment data extracted at this time has the power of a BCH signal, intercepting first intercepted data comprising a complete BCH signal from the last segment data; compensating the first intercepted data by taking the frequency of the frequency domain power peak point of the first intercepted data as a first frequency offset to obtain second intercepted data; frequency offset compensation is carried out on the second intercepted data through different second frequency offsets, UW correlation detection is carried out on the compensated data, the position of the BCH signal is obtained by comparing the UW correlation detection results, and the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset. According to the embodiment of the invention, the frame synchronization of the BCH signal is carried out during frequency offset estimation, the rapid synchronization performance of the wireless signal is improved, and the memory overhead is also reduced.

Description

Technical Field

[0001] The present application relates to the field of wireless communication technology, and in particular to a wireless synchronization method, apparatus, device and storage medium. Background Art

[0002] The initial synchronization of low-orbit satellites often has a large frequency deviation and a random time deviation. The conventional processing method is to first perform time domain energy detection, calculate the segmented energy of the received signal, compare the energy difference before and after, and roughly determine the BCH starting position by finding each segment energy step point; then, starting from this position, intercept the signal containing BCH; perform single-fold extraction and demodulation on the intercepted signal containing BCH, perform multiple FFT transformations on the sliding window, and save each FFT transformation result; find each FFT peak point, and confirm the wireless signal time deviation and frequency deviation by comparing all FFT peak results.

[0003] This method has the following problems:

[0004] 1) The algorithm is highly complex. The calculation process needs to save a large number of intermediate results of the FFT transform of each sliding window, which results in high memory overhead.

[0005] 2) Under low signal-to-noise ratio, the time domain energy detection method has a high probability of missed detection and false detection, is easily affected by interference, and has low detection sensitivity. Summary of the invention

[0006] In view of this, the embodiments of the present application provide a wireless synchronization method, apparatus, device and storage medium, which synchronize wireless signals while estimating the frequency; obtain high-multiple up-sampling data including the complete BCH signal through BCH signal energy detection in the frequency domain, so as to avoid the high probability of missed detection and false detection problems in time domain energy detection in high interference scenarios; and perform UW correlation detection on signals that have been compensated for different frequency offsets to accurately obtain BCH signal frame synchronization, thereby avoiding the large amount of memory consumption of the sliding FFT algorithm of the traditional method.

[0007] In a first aspect, an embodiment of the present application provides a wireless synchronization method, comprising: extracting segments of a wireless signal upsampled by a set multiple, and when the power of a BCH signal exists in the frequency domain space in the segmented data extracted this time, extracting first intercepted data including a complete BCH signal from multiple segmented data starting from the last segmented data; taking the frequency of the power peak point of the first intercepted data in the frequency domain space as the first frequency offset, performing a first frequency offset compensation on the first intercepted data to obtain second intercepted data; performing a second frequency offset compensation on the second intercepted data with a different second frequency offset, and performing UW correlation detection on each data after the second frequency offset compensation, and obtaining the position of the BCH signal by comparing the results of each UW correlation detection, wherein the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset.

[0008] From the above, the high-multiple up-sampled data including the complete BCH signal is obtained through the BCH signal energy detection in the frequency domain, so as to avoid the high probability of missed detection and false detection problems in the time domain energy detection in high interference scenarios; and the UW correlation detection is performed on the signal with different frequency offset compensation to accurately obtain the BCH signal frame synchronization, thus avoiding the large memory consumption of the sliding FFT algorithm of the traditional method.

[0009] In a possible implementation of the first aspect, the method of obtaining the position of the BCH signal by comparing the results of each UW correlation detection comprises: obtaining the peak value and index position of the correlation sequence corresponding to each second frequency offset compensation, wherein the correlation sequence corresponding to each second frequency offset compensation is the result of UW correlation detection of the second frequency offset compensated data; taking the maximum value among the peak values ​​of each of the correlation sequences at the index position of the corresponding correlation sequence as the time offset estimate of the second intercepted data; and obtaining the position of the BCH signal based on the time offset estimate and the BCH signal length.

[0010] From the above, the accurate time offset of the BCH signal is obtained through different second frequency offset compensations and UW sliding correlation detection, so as to avoid sliding FFT operation and save a large number of intermediate results of each FFT operation.

[0011] In a possible implementation of the first aspect, it also includes: obtaining third intercepted data corresponding to the actual BCH signal position from the correlation sequence corresponding to the maximum value according to the position of the BCH signal; downsampling the third intercepted data according to the set multiple and then performing conjugate point multiplication with the local UW sequence, and taking the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space as the third frequency deviation; and taking the sum of the first frequency deviation, the second frequency deviation corresponding to the maximum value and the third frequency deviation as the final frequency deviation of the wireless signal.

[0012] From the above, the third intercepted data is essentially data obtained by upsampling the actual BCH signal and undergoing two frequency offset compensations. The third frequency offset accurate to Hz is obtained according to the third intercepted data to obtain the final frequency offset of the wireless signal.

[0013] In a possible implementation manner of the first aspect, the method further includes: before downsampling the third intercepted data, filtering the third intercepted data, and replacing the previous third intercepted data with the filtered third intercepted data.

[0014] From the above, by filtering the noise left by downsampling, the third frequency deviation can be obtained more accurately.

[0015] In a possible implementation of the first aspect, the third truncated data is down-sampled according to the set multiple and then conjugate point multiplied with the local UW sequence, and the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space is taken as the third frequency deviation, including: down-sampling the third truncated data according to the set multiple to obtain fourth truncated data; conjugate point multiplying the fourth truncated data with the local UW sequence, and performing FFT transformation on the sequence after the point multiplication; and taking the difference between the position of the modulus square peak point of the transformation result and the zero frequency position as the third frequency deviation.

[0016] As described above, the third intercepted data is downsampled to 1 times the data and then correlated with the local UW sequence to obtain the third frequency offset of the third intercepted data accurate to Hz.

[0017] In a possible implementation of the first aspect, determining whether there is power of a BCH signal in the frequency domain space in the segmented data extracted this time includes: performing an FFT transform on the segmented data, filtering the modulus of the transform result, and obtaining a position P0 where the maximum value in the filtering result is located, and the filter length is greater than or equal to the BCH signal bandwidth W; when the ratio of the mean of the filtering result in the range of [P0-W, P0+W] to the mean of the filtering result in other positions is greater than a set ratio threshold, there is data of the BCH signal in the segmented data, otherwise, executing the judgment of the next segmented data.

[0018] From the above, the BCH signal energy in the frequency domain is quickly detected through FFT transformation to obtain high-multiple up-sampled data including the complete BCH signal, so as to avoid the high probability of missed detection and false detection problems in time domain energy detection under high interference scenarios.

[0019] In a possible implementation of the first aspect, the frequency of the power peak point of the first intercepted data in the frequency domain space is taken as the first frequency deviation, including: performing FFT transform on the first intercepted data, squaring and filtering the transform result; obtaining the difference between the position P1 of the maximum value in the filtering result and the zero frequency position as the first frequency deviation.

[0020] As described above, the first frequency deviation of the wireless signal is obtained through FFT transformation and the first intercepted data is compensated to reduce the residual frequency deviation therein to KHz.

[0021] In a possible implementation manner of the first aspect, each second frequency deviation increases by 250 Hz.

[0022] From the above, the second frequency deviation is increased by 250 Hz to improve the accuracy of UW sliding correlation detection.

[0023] In the second aspect, an embodiment of the present application provides a wireless synchronization device, including: a BCH power detection module, which is used to extract segments of a wireless signal sampled at a set multiple, and when the power of the BCH signal exists in the frequency domain space in the segmented data extracted this time, a first intercepted data including a complete BCH signal is intercepted from multiple segmented data starting from the last segmented data; a first frequency offset acquisition module, which is used to perform a first frequency offset compensation on the first intercepted data with the frequency of the power peak point of the first intercepted data in the frequency domain space as the first frequency offset, to obtain second intercepted data; a BCH position synchronization module, which is used to perform a second frequency offset compensation on the second intercepted data with a different second frequency offset, and perform UW correlation detection on each data after the second frequency offset compensation, and obtain the position of the BCH signal by comparing the results of each UW correlation detection, wherein the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset.

[0024] From the above, the high-multiple up-sampled data including the complete BCH signal is obtained through the BCH signal energy detection in the frequency domain, so as to avoid the high probability of missed detection and false detection problems in the time domain energy detection in high interference scenarios; and the UW correlation detection is performed on the signal with different frequency offset compensation to accurately obtain the BCH signal frame synchronization, thus avoiding the large memory consumption of the sliding FFT algorithm of the traditional method.

[0025] In a possible implementation of the second aspect, when the BCH position synchronization module obtains the position of the BCH signal by comparing the results of each UW correlation detection to obtain the position of the BCH signal, it is specifically used to: obtain the peak value and index position of the correlation sequence corresponding to each second frequency offset compensation, wherein the correlation sequence corresponding to each second frequency offset compensation is the result of UW correlation detection of the second frequency offset compensated data; the maximum value among the peak values ​​of each of the correlation sequences at the index position of the corresponding correlation sequence is the time offset estimate of the second intercepted data; and obtain the position of the BCH signal based on the time offset estimate and the BCH signal length.

[0026] From the above, the accurate time offset of the BCH signal is obtained through different second frequency offset compensations and UW sliding correlation detection, so as to avoid sliding FFT operation and save a large number of intermediate results of each FFT operation.

[0027] In a possible implementation of the second aspect, it also includes: a third frequency deviation acquisition module, which is used to obtain third intercepted data corresponding to the actual BCH signal position from the related sequence corresponding to the maximum value according to the position of the BCH signal; after downsampling the third intercepted data according to the set multiple, conjugate point multiplication is performed with the local UW sequence, and the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space is taken as the third frequency deviation; and the sum of the first frequency deviation, the second frequency deviation corresponding to the maximum value and the third frequency deviation is taken as the final frequency deviation of the wireless signal.

[0028] From the above, the third intercepted data is essentially data obtained by upsampling the actual BCH signal and undergoing two frequency offset compensations. The third frequency offset accurate to Hz is obtained according to the third intercepted data to obtain the final frequency offset of the wireless signal.

[0029] In a possible implementation manner of the second aspect, the method further includes: a filtering module, configured to filter the third intercepted data before down-sampling the third intercepted data.

[0030] From the above, by filtering the noise left by downsampling, the third frequency deviation can be obtained more accurately.

[0031] In a possible implementation of the second aspect, the third frequency deviation acquisition module is specifically used to, after downsampling the third intercepted data according to the set multiple and then conjugate point multiplying it with the local UW sequence, and taking the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space as the third frequency deviation, include: downsampling the third intercepted data according to the set multiple to obtain fourth intercepted data; conjugate point multiplying the fourth intercepted data with the local UW sequence, and performing FFT transformation on the sequence after the point multiplication; and taking the difference between the position of the modulus square peak point of the transformation result and the zero frequency position as the third frequency deviation.

[0032] As described above, the third intercepted data is downsampled to 1 times the data and then correlated with the local UW sequence to obtain the third frequency offset of the third intercepted data accurate to Hz.

[0033] In a possible implementation of the second aspect, when the BCH power detection module determines whether there is the power of the BCH signal in the frequency domain space in the segmented data extracted this time, it is specifically used to include: performing FFT transformation on the segmented data, filtering the modulus of the transformation result, and obtaining the position P0 where the maximum value in the filtering result is located, and the filter length is greater than or equal to the BCH signal bandwidth W; when the ratio of the mean of the filtering result in the range of [P0-W, P0+W] to the mean of the filtering result in other positions is greater than a set ratio threshold, there is data of the BCH signal in the segmented data, otherwise, executing the judgment of the next segmented data.

[0034] From the above, the BCH signal energy in the frequency domain is quickly detected through FFT transformation to obtain high-multiple up-sampled data including the complete BCH signal, so as to avoid the high probability of missed detection and false detection problems in time domain energy detection under high interference scenarios.

[0035] In a possible implementation of the second aspect, when obtaining the first frequency offset, the first frequency offset acquisition module is specifically used to: perform FFT transform on the first intercepted data, and square and filter the transform result; obtain the difference between the position P1 of the maximum value in the filtering result and the zero frequency position as the first frequency offset.

[0036] As described above, the first frequency deviation of the wireless signal is obtained through FFT transformation and the first intercepted data is compensated to reduce the residual frequency deviation therein to KHz.

[0037] In a possible implementation of the second aspect, each second frequency deviation increases by 250 Hz.

[0038] From the above, the second frequency deviation is increased by 250 Hz to improve the accuracy of UW sliding correlation detection.

[0039] In a third aspect, an embodiment of the present application provides a computing device, including:

[0040] bus;

[0041] A communication interface connected to the bus;

[0042] at least one processor connected to the bus; and

[0043] At least one memory is connected to the bus and stores program instructions, and when the program instructions are executed by the at least one processor, the at least one processor executes any implementation method of the first aspect of the present application.

[0044] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium having program instructions stored thereon, wherein when the program instructions are executed by a computer, the computer executes any implementation method described in the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A flowchart of a wireless synchronization method embodiment 1 of the present application;

[0046] Figure 2 This is a flow chart of a second embodiment of a wireless synchronization method of the present application;

[0047] Figure 3 This is a structural diagram of a wireless synchronization device embodiment 1 of the present application;

[0048] Figure 4 This is a structural diagram of a second embodiment of a wireless synchronization device of the present application;

[0049] Figure 5 A schematic diagram of the structure of a computing device according to various embodiments of the present application. DETAILED DESCRIPTION

[0050] In the following description, reference is made to “some embodiments”, which describe a subset of all possible embodiments, but it will be understood that “some embodiments” may be the same subset or different subsets of all possible embodiments and may be combined with each other without conflict.

[0051] In the following description, the terms "first\second\third, etc." or module A, module B, module C, etc. are only used to distinguish similar objects, or to distinguish different embodiments, and do not represent a specific ordering of the objects. It can be understood that the specific order or sequence can be interchanged where permitted, so that the embodiments of the present application described here can be implemented in an order other than that illustrated or described here.

[0052] In the following description, the numbers representing the steps, such as S110, S120, etc., do not necessarily mean that the steps must be executed in this manner. If permitted, the order of the previous and next steps can be interchanged, or the steps can be executed simultaneously.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein are only for the purpose of describing the embodiments of this application and are not intended to limit this application.

[0054] The embodiments of the present application provide a wireless synchronization method, apparatus, device and storage medium, the method comprising: extracting segments of a wireless signal upsampled at a set multiple, and when the power of a BCH signal exists in the frequency domain space in the segmented data extracted this time, extracting first intercepted data including a complete BCH signal from multiple segmented data starting from the last segmented data; taking the frequency of the power peak point of the first intercepted data in the frequency domain space as the first frequency offset, performing a first frequency offset compensation on the first intercepted data to obtain second intercepted data; performing a second frequency offset compensation on the second intercepted data with a different second frequency offset, and performing UW correlation detection on each data after the second frequency offset compensation, and obtaining the position of the BCH signal by comparing the results of each UW correlation detection, wherein the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset.

[0055] The technical solution of the embodiment of the present application is used to synchronize wireless signals while estimating the frequency; it also obtains high-multiple up-sampling data including the complete BCH signal through BCH signal energy detection in the frequency domain, so as to avoid the high probability of missed detection and false detection problems in time domain energy detection in high interference scenarios; it also performs UW correlation detection on signals that have been compensated for different frequency offsets to accurately obtain BCH signal frame synchronization, thereby avoiding the large amount of memory consumption of the sliding FFT algorithm of the traditional method.

[0056] The following describes various embodiments of the present application in conjunction with the accompanying drawings. Figure 1 A first embodiment of a wireless synchronization method is introduced.

[0057] Figure 1 The flowchart of a first embodiment of a wireless synchronization method is shown, including steps S110 to S140.

[0058] S110: extract segmented data in sequence according to the set length from the time domain data sampled from the wireless signal. When it is determined that the power of the BCH signal exists in the frequency domain space in the current segmented data, extract the first intercepted data including the complete BCH signal from the multiple segmented data starting from the last segmented data.

[0059] Among them, upsampling is high-multiple sampling, and the upsampling multiple can be set. For example, upsampling is performed by 16 times. The set length is obtained according to the processing capability of the frequency domain transform and the real-time performance of the frequency deviation. The higher the real-time performance of the frequency deviation, the shorter the segment length. The set length cannot exceed the processing capability of the frequency domain transform.

[0060] After obtaining the first intercepted data including the BCH signal, other segmented data are no longer retained, thereby reducing the consumption of subsequent storage resources. The first intercepted data is intercepted from multiple segmented data starting from the last segmented data, so that the first intercepted data includes a complete BCH signal, and the number of segments is obtained jointly according to the upsampling multiple, the length of the BCH signal and the length of the segment.

[0061] Among them, the frequency domain spatial data is obtained by performing FFT transformation on the high-multiple up-sampled data, and then it is determined whether the power of the BCH signal exists in the segmented data, so as to avoid the high probability of missed detection and false detection problems in time domain energy detection under high interference scenarios.

[0062] In some embodiments, the segmented data is subjected to an FFT transform, the modulus of the transform result is filtered, and the position P0 where the maximum value in the filtering result is located is obtained, and the filter length is greater than or equal to the BCH signal bandwidth W; when the ratio of the mean of the filtering result in the position range [P0-W, P0+W] to the mean of the filtering results in other positions is greater than a set ratio threshold, the segmented data contains BCH signal data, otherwise, the judgment of the next segmented data is executed.

[0063] S120: Taking the frequency of the maximum power of the first intercepted data in the frequency domain space as the first frequency offset, perform a first frequency offset compensation on the first intercepted data to obtain second intercepted data.

[0064] After one frequency offset compensation, the residual frequency offset of the second intercepted data is reduced to a smaller range of ±Khz.

[0065] In some embodiments, the first intercepted data is subjected to FFT transformation, and the transformation result is squared and filtered to obtain the difference between the maximum value position and the zero frequency position in the filtering result as the first frequency offset. The maximum value position and the zero frequency position are respectively the positions of the corresponding points of the FFT.

[0066] S130: Performing second frequency offset compensation on the second intercepted data using different second frequency offsets.

[0067] The absolute value of each second frequency deviation is smaller than the absolute value of the first frequency deviation, and different second frequency deviations are increased according to a set step length, and an integer multiple of the step length is equivalent to the absolute value of the first frequency deviation. In some embodiments, the step length of the second frequency deviation is set, and each second frequency deviation is obtained according to the step length. For example, when the absolute value of the first frequency deviation is about 1Khz, the step length is 250hz.

[0068] Among them, after the second frequency offset compensation, the residual frequency offset value of the signal is further reduced, which can be used for accurate frequency estimation without the need to detect the time offset through a sliding FFT that consumes a lot of memory resources.

[0069] S140: Perform UW correlation detection on each data after the second frequency offset compensation, and obtain the position of the BCH signal by comparing the results of each UW correlation detection.

[0070] Among them, when UW (unique word) correlation detection is performed on the data after the second frequency offset compensation, the UW correlation detection is a sliding correlation detection, and the UW sequence length is the local UW sequence obtained by upsampling according to the multiple set in S110. The length of the local UW sequence is the same as the BCH signal length and is stored locally.

[0071] Among them, obtaining the position of the BCH signal is to achieve frame synchronization of the BCH signal, and frame synchronization of other signals is performed based on this.

[0072] In some embodiments, the peak value and index position of the correlation sequence corresponding to each second frequency offset compensation are obtained, wherein the correlation sequence corresponding to each second frequency offset compensation is the result of UW correlation detection of the second frequency offset compensated data, and a sequence is obtained after each UW correlation detection, each point of the sequence is a correlation value, and the sequence is a correlation sequence; the maximum value among the peak values ​​of each of the correlation sequences at the index position of the corresponding correlation sequence is used as the time offset estimate of the second intercepted data; the position of the BCH signal is obtained according to the time offset estimate and the length of the BCH signal. From the above, the accurate time offset of the BCH signal is obtained through different second frequency offset compensations and UW sliding correlation detections to avoid sliding FFT operations and saving a large number of intermediate results of each FFT operation.

[0073] In some embodiments, the sum of the second frequency offset and the first frequency offset corresponding to the result of the UW correlation detection used to obtain the BCH frame synchronization is also used as the frequency offset of the wireless signal.

[0074] In some embodiments, the third intercepted data corresponding to the actual BCH signal position is obtained from the correlation sequence corresponding to the maximum value according to the position of the BCH signal, wherein the length of the third intercepted data is the product of the multiple set in BCH signal * S110; the third intercepted data is downsampled according to the set multiple and then conjugated with the local UW sequence, and the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space is the third frequency deviation; the sum of the first frequency deviation, the second frequency deviation corresponding to the maximum value and the third frequency deviation is the final frequency deviation of the wireless signal, wherein the third intercepted data is obtained according to the second intercepted data, and the second intercepted data is obtained according to the first intercepted data, so that when obtaining the frequency deviation of the entire signal, it is not necessary to retain the entire wireless signal data, only the first intercepted data needs to be retained, and the required resources are greatly reduced. From the above, the third intercepted data is essentially the data that is upsampled from the actual BCH signal and compensated for the frequency deviation twice. The third frequency deviation accurate to Hz is obtained according to the third intercepted data to obtain the final frequency deviation of the wireless signal.

[0075] In some embodiments, before downsampling the third intercepted data, the third intercepted data is filtered, and the filtered third intercepted data replaces the previous third intercepted data. Thus, by filtering the noise left by downsampling, the third frequency deviation is obtained more accurately.

[0076] In some embodiments, the third intercepted data is downsampled according to the set multiple to obtain the fourth intercepted data, wherein the set multiple is still the multiple set in S110, and when the third intercepted data is downsampled according to the set multiple, starting from the first data of the third intercepted data, one data is sampled every set multiple, and the length after downsampling is the same as the length of the BCH signal; the fourth intercepted data is conjugate point multiplied with the local UW sequence, and the sequence after the point multiplication is FFT transformed; the difference between the position of the modulus square peak point of the transformation result and the zero frequency position is used as the third frequency deviation. From the above, by correlating the third intercepted data with the local UW sequence after downsampling to 1 times the data, the third frequency deviation of the third intercepted data accurate to Hz is obtained.

[0077] In summary, a wireless synchronization method embodiment 1 is used to synchronize wireless signals during frequency estimation; high-multiple up-sampling data including a complete BCH signal is obtained through BCH signal energy detection in the frequency domain to avoid the high probability of missed detection and false detection problems in time domain energy detection under high interference scenarios; UW correlation detection is performed on signals that have been compensated for different frequency offsets to accurately obtain BCH signal frame synchronization, thereby avoiding the large amount of memory consumption of the sliding FFT algorithm of the traditional method.

[0078] A second wireless synchronization method embodiment is a detailed implementation method of the first wireless synchronization method embodiment, which has all its advantages and performs more accurate frequency offset compensation according to BCH signal frame synchronization to meet the frequency offset estimation requirements of satellite signals.

[0079] Figure 2 The flowchart of a second embodiment of a wireless synchronization method is shown, including steps S210 to S270.

[0080] S210: Extract segmented data in sequence according to the set length from the time domain data sampled by the set multiple of the wireless signal. When it is determined through FFT that the power of the BCH signal exists in the current segmented data, extract the first intercepted data including the complete BCH signal from the multiple segmented data starting from the last segmented data.

[0081] Among them, this step includes the following steps:

[0082] 1) After upsampling the time domain data of the wireless signal by a set multiple, extract the segmented data in sequence according to the set length.

[0083] 2) Perform FFT transformation on the segmented data, filter the modulus of the transformation result, and obtain the position P0 of the maximum value in the filtering result. The filter length is greater than or equal to the BCH signal bandwidth W.

[0084] 3) The mean of the filtering results within the range of [P0-W, P0+W] (equivalent to the bandwidth range of [-W+W]) is recorded as signal_pwr, and the mean of the filtering results in other positions (equivalent to outside the bandwidth range of [-W+W]) is recorded as noise_pwr. When the ratio of signal_pwr to noise_pw is greater than the set ratio threshold, there is BCH signal data in the segmented data, and the first intercepted data including the complete BCH signal is intercepted from the multiple segmented data starting from the last segmented data. Otherwise, the judgment of the next segmented data is executed.

[0085] Among them, the detection results of the above methods are slightly different under different signal-to-noise ratios, specifically:

[0086] ■When the SNR is high, the segmented data contains fewer valid BCH signals, which can also be successfully detected;

[0087] ■When the SNR is low, the segmented data needs to contain more valid BCH signals to be successfully detected.

[0088] To ensure that BCH is completely retrieved, when a segmented data is detected successfully, the starting position of the BCH interception signal should be the starting position of the previous segmented data before the currently detected BCH segmented data. According to the BCH length set by the protocol, all segmented data that may contain BCH are intercepted from the starting position.

[0089] Among them, the BCH frequency domain energy detection method in this step has a missed detection and false detection performance that is more than 1db higher than that of the time domain energy detection S220: Perform FFT transformation on the first intercepted data, and square and filter the transformation result to obtain the difference between the peak point position P1 and the zero frequency position in the filtering result as the first frequency offset, and use the first frequency offset to perform the first frequency offset compensation on the first intercepted data to obtain the second intercepted data.

[0090] After the first intercepted data undergoes the first frequency offset compensation of the first frequency offset, the residual frequency offset in the second intercepted data is reduced to a smaller range of ±Khz.

[0091] S230: Performing second frequency offset compensation on the second intercepted data using different second frequency offsets.

[0092] The second intercepted data is subjected to a second frequency offset compensation according to a second frequency offset of a set step length Δf (for example, set to 250 Hz), and the compensation range is [-Khz+Khz].

[0093] Among them, if UW correlation detection is directly performed on the second intercepted data after the first frequency offset compensation, the UW correlation characteristics in BCH are greatly affected by the frequency offset. When the frequency offset exceeds a certain value, its autocorrelation becomes worse. Therefore, before performing the correlation detection, the signal needs to be stepped for the second time for frequency offset compensation.

[0094] S240: Perform UW correlation detection on each data after the second frequency offset compensation, obtain the actual position of the BCH signal according to each UW correlation detection data, and thereby obtain the third intercepted data aligned with the actual BCH signal position.

[0095] Specifically, this step includes the following steps:

[0096] 1) Perform UW correlation detection on each result after the second frequency offset compensation, and save the peak value and index position in each correlation sequence obtained. The UW correlation detection is a sliding correlation detection, and the length of the UW sequence is obtained by upsampling the local UW sequence according to the multiple set in S210. The length of the local UW sequence is the same as the BCH signal length and is saved locally.

[0097] 2) Find the maximum value among the peak values ​​of all sub-correlation sequences. The peak index position of the correlation sequence corresponding to the maximum value is the time offset estimate of the second intercepted data (also the time offset estimate of the actual wireless signal), and the corresponding second frequency offset is the pre-frequency offset compensation value. Among them, this time offset estimation is combined with the known BCH length to determine the BCH start position and end position, that is, the actual position of the BCH. After compensation by the pre-frequency offset compensation value, the residual frequency offset value of the signal is further reduced.

[0098] 3) Obtain third intercepted data aligned with the actual BCH signal position from the second intercepted data compensated by the pre-frequency offset compensation value according to the time offset estimation of the second intercepted data. The position obtained by the time offset estimation is taken as the starting position, and the data with a length equal to the multiple set in BCH length * S210 is obtained from the second intercepted data compensated by the pre-frequency offset compensation value as the third intercepted data.

[0099] S250: Filter the third intercepted data, and replace the previous third intercepted data with the filtered third intercepted data.

[0100] S260: The third intercepted data is downsampled according to a set multiple to obtain the fourth intercepted data, the fourth intercepted data is conjugate-point-multiplied with the local UW sequence, and the sequence after the point multiplication is subjected to FFT transformation, and the difference between the position of the modulus square peak point of the transformation result and the zero-frequency position is used as the third frequency deviation.

[0101] The position of the modulus square peak point and the zero frequency position of the transformation result are both point positions in the FFT space and can be converted to the frequency domain space.

[0102] The fourth intercepted data is essentially the received BCH signal that has undergone two frequency offset compensations. The third intercepted data is essentially the received BCH signal that has undergone two frequency offset compensations and upsampled. Downsampling is to take one sample out of every consecutive set multiple samples. The set multiple of downsampling in this step is consistent with the multiple set in step S210.

[0103] The position of the modulus square peak point and the zero frequency position of the transformation result are both point positions in the FFT space and can be converted to the frequency domain space.

[0104] S270: Taking the sum of the first frequency offset, the pre-frequency offset compensation value and the third frequency offset as the final frequency offset of the wireless signal.

[0105] The final frequency deviation of the wireless signal obtained in this step is a frequency deviation value accurate to hz, which is used to achieve synchronization of wireless signals including satellite signals.

[0106] In summary, the second embodiment of a wireless synchronization method not only realizes BCH signal frame synchronization, but also performs more accurate frequency offset compensation based on the BCH signal frame synchronization to meet the frequency offset estimation requirement of the satellite signal.

[0107] Combine the following Figure 3 A first embodiment of a wireless synchronization device is introduced.

[0108] A wireless synchronization device embodiment 1 is used to implement the method of a wireless synchronization method embodiment 1, and has all its advantages.

[0109] Figure 3The structure of a first embodiment of a wireless synchronization device is shown, including: a BCH energy detection module 310, a first frequency offset acquisition module 320, a second frequency offset acquisition module 330, and a BCH position synchronization module 340.

[0110] The BCH energy detection module 310 is used to extract segmented data in sequence according to a set length from the time domain data sampled from the wireless signal. When it is determined that the power of the BCH signal exists in the frequency domain space in the current segmented data, the first intercepted data including the complete BCH signal is intercepted from the multiple segmented data starting from the last segmented data. For its working principle and advantages, please refer to step S110 of the first embodiment of a wireless synchronization method.

[0111] The first frequency offset obtaining module 320 is used to take the frequency of the maximum power of the first intercepted data in the frequency domain space as the first frequency offset, perform the first frequency offset compensation on the first intercepted data, and obtain the second intercepted data. For its working principle and advantages, please refer to step S120 of the first embodiment of a wireless synchronization method.

[0112] The second frequency offset obtaining module 330 is used to perform a second frequency offset compensation on the second intercepted data with a different second frequency offset. For its working principle and advantages, please refer to step S130 of the first embodiment of a wireless synchronization method.

[0113] The BCH position synchronization module 340 is used to perform UW correlation detection on the data after the second frequency offset compensation, and obtain the position of the BCH signal by comparing the results of each UW correlation detection. For its working principle and advantages, please refer to step S140 of the first embodiment of a wireless synchronization method.

[0114] Combine the following Figure 4 A second embodiment of a wireless synchronization device is introduced.

[0115] A wireless synchronization device embodiment 2 is used to implement the method of a wireless synchronization method embodiment 2, and has all its advantages.

[0116] Figure 4 The structure of a second embodiment of a wireless synchronization device is shown, including: a BCH energy detection module 410, a first frequency deviation acquisition module 420, a second frequency deviation acquisition module 430, a BCH position synchronization module 440, and a filtering module 450.

[0117] The third frequency offset obtaining module 460 and the final frequency offset obtaining module 470 .

[0118] The BCH energy detection module 410 is used to extract segmented data in sequence according to the set length from the time domain data sampled by the set multiple of the wireless signal. When the power of the BCH signal exists in the current segmented data through FFT, the first intercepted data including the complete BCH signal is intercepted from the multiple segmented data starting from the last segmented data. For its working principle and advantages, please refer to step S210 of the second embodiment of a wireless synchronization method.

[0119] The first frequency offset acquisition module 420 is used to perform FFT transformation on the first intercepted data, square and filter the transformation result, obtain the difference between the peak point position P1 and the zero frequency position in the filtering result as the first frequency offset, and use the first frequency offset to perform the first frequency offset compensation on the first intercepted data to obtain the second intercepted data. For its working principle and advantages, please refer to step S220 of the second embodiment of a wireless synchronization method.

[0120] The second frequency offset acquisition module 430 is used to perform a second frequency offset compensation on the second intercepted data with a different second frequency offset. Perform UW correlation detection on the compensated data to obtain the second frequency offset compensated data corresponding to the maximum value of each UW correlation detection value, and obtain the third intercepted data aligned with the actual BCH signal position therefrom. For its working principle and advantages, please refer to step S230 of embodiment 2 of a wireless synchronization method.

[0121] The BCH position synchronization module 440 is used to perform UW correlation detection on the data after the second frequency offset compensation, obtain the actual position of the BCH signal according to each UW correlation detection data, and obtain the third intercepted data aligned with the actual BCH signal position. For its working principle and advantages, please refer to step S240 of the second embodiment of a wireless synchronization method.

[0122] The filtering module 450 is used to filter the third intercepted data and replace the previous third intercepted data with the filtered third intercepted data. For its working principle and advantages, please refer to step S250 of the second embodiment of a wireless synchronization method.

[0123] The third frequency offset acquisition module 460 is used to downsample the third intercepted data according to a set multiple to obtain the fourth intercepted data, perform a conjugate point multiplication on the fourth intercepted data and the local UW sequence, and perform FFT transformation on the sequence after the point multiplication, and use the difference between the position of the modulus square peak point of the transformation result and the zero frequency position as the third frequency offset. For its working principle and advantages, please refer to step S260 of embodiment 2 of a wireless synchronization method.

[0124] The final frequency offset obtaining module 470 is used to use the sum of the first frequency offset, the pre-frequency offset compensation value and the third frequency offset as the final frequency offset of the wireless signal. For its working principle and advantages, please refer to step S270 of the second embodiment of a wireless synchronization method.

[0125] The present application embodiment also provides a computing device, Figure 5 Detailed introduction.

[0126] The computing device 500 includes a processor 510 , a memory 520 , a communication interface 530 , and a bus 540 .

[0127] It should be understood that the communication interface 530 in the computing device 500 shown in this figure can be used to communicate with other devices.

[0128] The processor 510 may be connected to a memory 520. The memory 520 may be used to store the program code and data. Therefore, the memory 520 may be a storage unit inside the processor 510, or an external storage unit independent of the processor 510, or a component including a storage unit inside the processor 510 and an external storage unit independent of the processor 510.

[0129] Optionally, the computing device 500 may further include a bus 540. The memory 520 and the communication interface 530 may be connected to the processor 510 via the bus 540. The bus 540 may be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus 540 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the figure is represented by only one line, but it does not mean that there is only one bus or one type of bus.

[0130] It should be understood that in the embodiment of the present application, the processor 510 can adopt a central processing unit (CPU). The processor can also be other general-purpose processors, digital signal processors (DSP), application specific integrated circuits (ASIC), field programmable gate arrays (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. Or the processor 510 uses one or more integrated circuits to execute related programs to implement the technical solutions provided in the embodiments of the present application.

[0131] The memory 520 may include a read-only memory and a random access memory, and provides instructions and data to the processor 510. A portion of the processor 510 may also include a nonvolatile random access memory. For example, the processor 510 may also store information on the device type.

[0132] When the computing device 500 is running, the processor 510 executes the computer-executable instructions in the memory 520 to perform the operation steps of each method embodiment.

[0133] It should be understood that the computing device 500 according to the embodiment of the present application can correspond to the corresponding subjects in the methods according to the embodiments of the present application, and the above-mentioned and other operations and / or functions of each module in the computing device 500 are respectively for implementing the corresponding processes of each method of the present embodiment. For the sake of brevity, they will not be repeated here.

[0134] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0135] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0136] In the several embodiments provided in the present application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of the units is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0137] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0138] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0139] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application can be essentially or partly embodied in the form of a software product that contributes to the prior art. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the methods described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program codes, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk.

[0140] The embodiment of the present application also provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, it is used to execute the operating steps of each method embodiment.

[0141] The computer storage medium of the embodiment of the present application can adopt any combination of one or more computer-readable media.Computer-readable media can be computer-readable signal media or computer-readable storage media.Computer-readable storage media can be, for example, but not limited to, electrical, magnetic, optical, electromagnetic, infrared, or semiconductor systems, devices or devices, or any combination of the above.More specific examples (non-exhaustive lists) of computer-readable storage media include, electrical connections with one or more wires, portable computer disks, hard disks, random access memories (RAM), read-only memories (ROM), erasable programmable read-only memories (EPROM or flash memory), optical fibers, portable compact disk read-only memories (CD-ROM), optical storage devices, magnetic storage devices, or any suitable combination of the above.In this document, computer-readable storage media can be any tangible medium containing or storing programs, which can be used by instruction execution systems, devices or devices or used in combination with them.

[0142] Computer-readable signal media may include data signals transmitted in baseband or as part of a carrier wave, which carry computer-readable program code. Such transmitted data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, transmit, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0143] The program code embodied on the computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0144] Computer program code for performing the operation of the present application can be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages, such as Java, Smalltalk, C++, and conventional procedural programming languages, such as "C" language or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as an independent software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., using an Internet service provider to connect through the Internet).

[0145] Note that the above are only preferred embodiments of the present application and the technical principles used. Those skilled in the art will understand that the present application is not limited to the specific embodiments described herein, and that various obvious changes, readjustments and substitutions can be made by those skilled in the art without departing from the scope of protection of the present application. Therefore, although the present application is described in more detail through the above embodiments, the present application is not limited to the above embodiments, and may also include more other equivalent embodiments without departing from the concept of the present application, all of which belong to the scope of protection of the present application.

Claims

1. A wireless signal synchronization method, characterized in that: include: Extracting the wireless signal upsampled by a set multiple in segments, when the segmented data extracted this time has the power of the BCH signal in the frequency domain space, extracting the first intercepted data including the complete BCH signal from the multiple segmented data starting from the last segmented data; Taking the frequency of the power peak point of the first intercepted data in the frequency domain space as the first frequency offset, performing a first frequency offset compensation on the first intercepted data to obtain second intercepted data; The second intercepted data is subjected to a second frequency offset compensation with a different second frequency offset, and UW correlation detection is performed on each second frequency offset compensated data. The position of the BCH signal is obtained by comparing the results of each UW correlation detection, wherein the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset.

2. The method according to claim 1, characterized in that: The obtaining of the position of the BCH signal by comparing the results of the UW correlation detections comprises: Obtaining a peak value and an index position of a correlation sequence corresponding to each second frequency offset compensation, wherein the correlation sequence corresponding to each second frequency offset compensation is a result of performing UW correlation detection on data of the second frequency offset compensation; The maximum value among the peak values ​​of each of the correlation sequences at the index position of the corresponding correlation sequence is used as the time deviation estimation of the second intercepted data; The position of the BCH signal is obtained according to the time offset estimation and the BCH signal length.

3. The method according to claim 2, characterized in that: Also includes: Obtaining third intercepted data corresponding to the actual BCH signal position from the correlation sequence corresponding to the maximum value according to the position of the BCH signal; After downsampling the third intercepted data according to the set multiple, the data is conjugate-dot-multiplied with the local UW sequence, and the frequency of the power peak point of the sequence after the dot-multiplication in the frequency domain space is taken as the third frequency offset; The sum of the first frequency offset, the second frequency offset corresponding to the maximum value, and the third frequency offset is taken as the final frequency offset of the wireless signal.

4. The method according to claim 3, characterized in that: The step of downsampling the third intercepted data according to the set multiple and then performing conjugate point multiplication with the local UW sequence, and taking the frequency of the power peak point of the sequence after the point multiplication in the frequency domain space as the third frequency offset, comprises: The third intercepted data is downsampled according to the set multiple to obtain fourth intercepted data; Conjugate point multiplication of the fourth intercepted data and the local UW sequence, and perform FFT transformation on the sequence after the point multiplication; The difference between the position of the modulus square peak point of the transformation result and the zero frequency position is used as the third frequency offset.

5. The method according to claim 3, characterized in that: Also includes: Before the down-sampling is performed on the third intercepted data, the third intercepted data is further filtered.

6. The method according to claim 1, characterized in that: Determine whether the power of the BCH signal exists in the frequency domain space in the segmented data extracted at the time, including: Perform FFT transformation on the segmented data, filter the modulus of the transformation result, and obtain the position P0 of the maximum value in the filtering result, and the filter length is greater than or equal to the BCH signal bandwidth W; When the ratio of the mean value of the filtering results within the range of [P0-W, P0+W] to the mean value of the filtering results in other positions is greater than the set ratio threshold, the segmented data contains BCH signal data, otherwise, the judgment of the next segmented data is executed.

7. The method according to claim 1, characterized in that: The frequency of the power peak point of the first intercepted data in the frequency domain space is taken as the first frequency deviation, including: Performing FFT transformation on the first intercepted data, and squaring and filtering the transformation result; The difference between the position P1 of the maximum value in the filtering result and the zero-frequency position is obtained as the first frequency offset.

8. A wireless signal synchronization device, characterized in that: include: A BCH power detection module is used to extract the wireless signal upsampled by a set multiple in segments, and when the power of the BCH signal exists in the frequency domain space in the segmented data extracted this time, extract the first intercepted data including the complete BCH signal from the multiple segmented data starting from the last segmented data; A first frequency offset obtaining module, configured to perform a first frequency offset compensation on the first intercepted data by taking the frequency of the power peak point of the first intercepted data in the frequency domain space as the first frequency offset, so as to obtain second intercepted data; The BCH position synchronization module is used to perform a second frequency offset compensation on the second intercepted data with a different second frequency offset, and perform UW correlation detection on each data after the second frequency offset compensation, and obtain the position of the BCH signal by comparing the results of each UW correlation detection, wherein the absolute value of each second frequency offset is smaller than the absolute value of the first frequency offset.

9. A computing device, characterized in that include, bus; A communication interface connected to the bus; at least one processor connected to the bus; as well as At least one memory is connected to the bus and stores program instructions, and when the program instructions are executed by the at least one processor, the at least one processor executes the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: Program instructions are stored thereon, and when the program instructions are executed by a computer, the computer is caused to execute the method according to any one of claims 1 to 7.

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