A frequency offset tracking method, apparatus, device and medium

Abstract

This application discloses a frequency offset tracking method, apparatus, device, and medium, relating to the field of wireless communication. The method involves receiving a burst direct sequence spread spectrum signal; generating multiple parallel frequency correction values ​​based on the burst direct sequence spread spectrum signal and a local carrier; wherein the local carrier is generated based on the burst direct sequence spread spectrum signal; despreading the multiple parallel frequency correction values ​​to generate corresponding multiple parallel correlation matching values; merging the multiple parallel correlation matching values; and performing frequency offset tracking using a frequency-locked loop method and the merged correlation matching values. Therefore, the above scheme performs parallel multi-path frequency offset correction on the received burst direct sequence spread spectrum signal and then performs frequency offset tracking using a frequency-locked loop method. This not only achieves high-precision frequency offset tracking but also adapts to large frequency offset change rates, enabling frequency tracking of burst direct sequence spread spectrum signals under high dynamic conditions.

Claims

1. A frequency offset tracking method, characterized in that, include: Receive burst direct sequence spread spectrum signals; Multiple parallel frequency correction values ​​are generated based on the burst direct sequence spread spectrum signal and the local carrier; wherein the local carrier is generated based on the burst direct sequence spread spectrum signal. The frequency correction values ​​of the multi-path parallel processing are despread to generate the corresponding correlation matching values ​​of the multi-path parallel processing. Merge the relevant matching values ​​from multiple parallel paths; Frequency offset tracking is performed based on the frequency-locked loop method and the merged relevant matching values; The relevant matching values ​​for merging multiple parallel paths include: Signal-to-noise ratio (SNR) estimates are performed on the correlation matching values ​​of the multiple parallel paths, and corresponding SNR values ​​for each path are generated, as shown in the following formula: ； ； ； in, The number of symbols within a frame; Obtain the multiple surviving paths with the largest signal-to-noise ratio (SNR) value among the multiple paths; Multiple surviving paths are merged according to preset rules to generate the merged relevant matching value; The preset rules include: ； in, The merged relevant matching values, The relevant matching values ​​are obtained through multiple parallel paths. For weight values, , The signal-to-noise ratio values ​​for the multiple channels are as follows. , , For the spreading code length, , For the number of paths, The surviving path with the largest signal-to-noise ratio; The frequency calibration value for despreading multiple parallel paths, and the corresponding multi-parallel related matching value generated by iteratively: Retrieve the local spreading code stored locally; The frequency calibration values ​​generated in multiple parallel paths are correlated with the local spreading code to generate corresponding correlation matching values ​​in multiple parallel paths, as shown in the following formula: ； in, , This is the parallel frequency-corrected signal of the l-th channel. This is the chip value with index (m mod N) in the local spreading code sequence.

2. The frequency offset tracking method according to claim 1, characterized in that, The process of generating the local carrier includes: Obtain the initial frequency offset value of the burst direct sequence spread spectrum signal; The local carrier is generated in parallel based on the initial frequency offset value and the locally stored frequency offset change rate value.

3. The frequency offset tracking method according to claim 1, characterized in that, Before generating multiple parallel frequency calibration values ​​based on the burst direct sequence spread spectrum signal and the local carrier, the method further includes: The received burst direct sequence spread spectrum signal is subjected to frequency conversion processing, low-pass filtering processing, and sampling processing.

4. The frequency offset tracking method according to any one of claims 1 to 3, characterized in that, After performing frequency offset tracking based on the frequency-locked loop method and the merged correlation matching value, the method further includes: The burst direct sequence spread spectrum signal is demodulated.

5. A frequency offset tracking device, characterized in that, include: The receiving module is used to receive burst direct sequence spread spectrum signals; A generation module is used to generate multiple parallel frequency correction values ​​based on the burst direct sequence spread spectrum signal and a local carrier; wherein the local carrier is generated based on the burst direct sequence spread spectrum signal. The despreading module is used to despread the frequency correction values ​​of the multiple parallel paths and generate corresponding correlation matching values ​​of the multiple parallel paths. A merging module is used to merge the relevant matching values ​​from multiple parallel paths; The frequency offset tracking module is used to perform frequency offset tracking based on the frequency-locked loop method and the merged correlation matching value; The relevant matching values ​​for merging multiple parallel paths include: Signal-to-noise ratio (SNR) estimates are performed on the correlation matching values ​​of the multiple parallel paths, and corresponding SNR values ​​for each path are generated, as shown in the following formula: ； ； ； in, The number of symbols within a frame; Obtain the multiple surviving paths with the largest signal-to-noise ratio (SNR) value among the multiple paths; Multiple surviving paths are merged according to preset rules to generate the merged relevant matching value; The preset rules include: ； in, The merged relevant matching values, The relevant matching values ​​are obtained through multiple parallel paths. For weight values, , The signal-to-noise ratio values ​​for the multiple channels are as follows. , , For the spreading code length, , For the number of paths, The surviving path with the largest signal-to-noise ratio; The frequency calibration value for despreading multiple parallel paths, generating corresponding multi-parallel related matching values ​​includes: Retrieve the local spreading code stored locally; The frequency calibration values ​​generated in multiple parallel paths are correlated with the local spreading code to generate corresponding correlation matching values ​​in multiple parallel paths, as shown in the following formula: ； in, , This is the parallel frequency-corrected signal of the l-th channel. This is the chip value with index (m mod N) in the local spreading code sequence.

6. A frequency offset tracking device, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the steps of the frequency offset tracking method as described in any one of claims 1 to 4.

7. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, implements the steps of the frequency offset tracking method as described in any one of claims 1 to 4.

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