Signal processing methods and apparatuses, receivers and electronic equipment for GFSK demodulation

Abstract

This invention discloses a signal processing method, apparatus, receiver, and electronic device for GFSK demodulation. The method includes: obtaining a local angle sequence of a theoretical GFSK modulated signal based on a preset synchronization word; obtaining a reference angle difference sequence based on the local angle sequence; obtaining a signal angle sequence based on the received baseband signal; obtaining a window angle difference sequence corresponding to each window state from the signal angle sequence based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence; and determining the synchronization position in the received baseband signal for GFSK demodulation based on the window state with the highest similarity to the reference angle difference sequence; or including: determining the interference caused by the previous symbol sequence and the next symbol sequence according to the preset synchronization word; and performing synchronization word decision by eliminating interference based on the synchronization position. Therefore, this invention can reduce computational complexity, thereby reducing system computational cost and improving system demodulation performance.

Description

Technical Field

[0001] This disclosure relates to digital signal processing techniques, and more specifically to signal processing methods and apparatus, receivers and electronic devices for Gaussian Frequency Shift Keying (GFSK) demodulation. Background Technology

[0002] Frequency Shift Keying (FSK) is a frequency modulation scheme in which digital information is transmitted by discrete frequency variations of a carrier signal. Gaussian FSK (GFSK) is an improvement on FSK, in which instead of directly modulating the carrier signal frequency with data symbols and changing the frequency instantaneously at the beginning of each symbol, a pulse-shaping Gaussian filter is used to filter the data pulses before modulating the carrier signal. The Gaussian filter makes the transition between symbols smooth. GFSK is widely used in low data rate personal communication standards, such as, but not limited to, classic Bluetooth. Bluetooth Low Energy (BLE) LowEnergy (LE) and 802.11 protocol.

[0003] At the GFSK modulation end (e.g., on the transmitter side), a Gaussian filter first filters the rectangular pulse sequence representing the sequence of data symbols to be transmitted to generate a shaped pulse signal; the FSK modulator uses the shaped pulse signal to modulate the frequency of the carrier signal to generate the GFSK modulated signal; the GFSK modulated signal is then transmitted as an RF signal through the transmitter back-end and antenna. At the GFSK demodulation end (e.g., on the receiver side), the RF front-end generates a complex (IQ) sampled signal from the RF GFSK modulated signal captured by the antenna, and the baseband circuit performs GFSK demodulation by processing the IQ sampled signal to obtain the original data symbol sequence.

[0004] At the GFSK demodulation end, synchronization of the received signal is required to ensure the accuracy of GFSK demodulation. For example, one known GFSK demodulation synchronization method used for Bluetooth Low Energy involves correlating the received signal with a locally generated standard sequence in the time domain to find the correlation peak. However, this method is complex and easily affected by AGC regulation, making the decision on the access address code a bottleneck. Summary of the Invention

[0005] The embodiments of the present invention aim to provide a signal processing method and apparatus, receiver and electronic device for GFSK demodulation, so as to at least solve the problems in the prior art described above.

[0006] An embodiment of the present invention provides a signal processing method for GFSK demodulation, comprising: S110, obtaining a local angle sequence of a theoretical GFSK modulated signal based on a preset synchronization word; S120, obtaining a reference angle difference sequence based on the local angle sequence; S130, obtaining a signal angle sequence based on a received baseband signal; S140, obtaining a window angle difference sequence corresponding to each window state from the signal angle sequence based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence; and S150, determining the synchronization position for GFSK demodulation in the received baseband signal based on the window state with the highest similarity to the reference angle difference sequence.

[0007] Embodiments of the present invention also provide a signal processing method for GFSK demodulation, comprising: determining interference caused by the previous symbol sequence and the next symbol sequence according to a preset synchronization word; and making a synchronization word decision by eliminating the interference based on a predetermined synchronization position.

[0008] Embodiments of the present invention also provide a signal processing apparatus for GFSK demodulation, comprising: a local angle sequence acquisition module configured to acquire a local angle sequence of a theoretical GFSK modulated signal based on a preset synchronization word; a reference angle difference sequence acquisition module configured to acquire a reference angle difference sequence based on the local angle sequence; a signal angle sequence acquisition module configured to acquire a signal angle sequence based on a received baseband signal; a window angle difference sequence acquisition module configured to acquire a window angle difference sequence corresponding to each window state based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence; and a synchronization position determination module configured to determine the synchronization position in the baseband signal for GFSK demodulation based on the window state with the highest similarity between the window angle difference sequence and the reference angle difference sequence.

[0009] Embodiments of the present invention also provide a signal processing apparatus for GFSK demodulation, comprising: an interference determination module configured to determine interference caused by a preceding symbol sequence and a following symbol sequence based on a preset synchronization word; and a synchronization word decision module configured to make a synchronization word decision by eliminating the interference based on a predetermined synchronization position.

[0010] Embodiments of the present invention also provide a receiver including the aforementioned signal processing apparatus for GFSK demodulation.

[0011] Embodiments of the present invention also provide an electronic device, including a processor and a storage device, wherein the storage device stores program instructions that, when executed by the processor, cause the electronic device to perform the aforementioned signal processing method for GFSK demodulation. Attached Figure Description

[0012] Figure 1 This is a schematic flowchart of a signal processing method for GFSK demodulation according to an embodiment of the present invention;

[0013] Figure 2 This is a schematic diagram of the BLE data frame structure;

[0014] Figure 3 A schematic structural diagram of a signal processing apparatus for GFSK demodulation according to an embodiment of the present invention; and

[0015] Figure 4 This is a schematic structural diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0016] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0017] Figure 1 This is a flowchart of a signal processing method for GFSK demodulation according to an embodiment of the present invention. This embodiment is applicable to wireless communication standards including but not limited to Bluetooth Low Energy (BLE). The signal processing method for GFSK demodulation provided in this embodiment can be executed by a signal processing device for GFSK demodulation provided in an embodiment of the present invention. This device can be implemented by software and / or hardware and integrated into a receiver or electronic device.

[0018] like Figure 1 As shown, the signal processing method for GFSK demodulation includes the following steps.

[0019] S110: Obtain the local angle sequence of the theoretical GFSK modulated signal based on the preset synchronization word.

[0020] It is understood that the preset synchronization word is the synchronization code sequence in the signal frame structure to be demodulated, and therefore is preset in the signal processing device (i.e., demodulation end) used for GFSK demodulation. In some embodiments, when the above method is specifically applied to BLE, the synchronization word can be an access address. Figure 2 As shown, the access address length is 4 bytes, or 32 bits in total.

[0021] In some embodiments, S110 may include: generating the theoretical GFSK modulated signal by upsampling and GFSK modulation of the synchronization word; and obtaining a local angle sequence by performing angle calculation on the theoretical GFSK modulated signal. For example, the synchronization word is upsampled by a preset multiple. Exemplarily, the length of the theoretical GFSK modulated signal (and the local angle sequence) may be L. SW *OSR+1, where L SW The bit length of the synchronization word is denoted by , and OSR is the upsampling factor.

[0022] Taking BLE application scenarios as an example, the local angle sequence pgfsk can be defined as pgfsk = ANGLE(GFSK(UPSAMPLE(AA))), where UPSAMPLE represents upsampling, GFSK represents GFSK modulation, ANGLE represents angle calculation, and AA refers to the access address used for BLE.

[0023] S120: Obtain a reference angle difference sequence based on the local angle sequence.

[0024] In some embodiments, S120 may include: generating a first sampled angle sequence by first downsampling the local angle sequence, wherein the first downsampling is the same multiple as the upsampling; and obtaining an angle difference sequence of the first sampled angle sequence as the reference angle difference sequence. For example, the local angle sequence is downsampled by a preset multiple (e.g., OSR) used for upsampling the synchronization word. For example, the i-th term of the first sampled angle sequence is the angle value of the (1+(i-1)*OSR)-th term in the local angle sequence, where i is from 1 to L. SW A positive integer of +1, where the j-th term of the reference angle difference sequence is the angle difference between the (j+1)-th term and the j-th term in the first sampled angle sequence, where j is from 1 to L. SW Positive integers.

[0025] For example, the reference angle difference sequence can be defined as pgfsk_diff = pgfsk(1 + OSR:OSR:end) – pgfsk(1:OSR:end - OSR), where end refers to L. SW *OSR+1.

[0026] S130: Obtain the signal angle sequence based on the received baseband signal.

[0027] In some embodiments, S130 may include: generating the received baseband signal by processing the received signal, wherein the processing includes sampling at a sampling rate that is the same multiple of the upsampling; and obtaining the signal angle sequence by performing an angle calculation on the received baseband signal. For example, sampling is performed at a preset multiple (e.g., OSR) used for upsampling the synchronization word as the sampling rate.

[0028] For example, the signal angle sequence can be defined as rx_phase = ANGLE(rx_sig), where rx_sig represents the received baseband signal.

[0029] S140: Based on the sliding window, obtain the window angle difference sequence corresponding to each window state from the signal angle sequence, wherein the size of the sliding window is determined by the length of the local angle sequence.

[0030] In some embodiments, S140 may include: for each window state, generating a second sampled angle sequence by second downsampling a corresponding subsequence within the window extracted from the signal angle sequence, wherein the second downsampling is the same multiple as the upsampling; and obtaining an angle difference sequence of the second sampled angle sequence as the window angle difference sequence. For example, the size of the sliding window may be L. SW *OSR+1, where the step size of the sliding window can be one signal angle (i.e., corresponding to one received baseband signal sampling point). For example, the sub-sequence within the corresponding window is downsampled using a preset multiple (e.g., OSR) for upsampling the synchronization word. For instance, the i-th term of each second sampling angle sequence is the (1+(i-1)*OSR)-th angle value in the corresponding sub-sequence within the window, where i is from 1 to L. SW A positive integer of +1, where the j-th term of each window angle difference sequence is the angle difference between the (j+1)-th term and the j-th term in the corresponding second sampling angle sequence, where j is from 1 to L. SW Positive integers.

[0031] For example, the window angle difference sequence can be defined as phase_diff_win(idx) = phase_diff(idx:idx+win-1), where phase_diff = rx_phase(1+OSR:OSR:end) – rx_phase(1:OSR:end-OSR), and idx represents the position (e.g., index or number) of the signal angle element (in the signal angle sequence) at the beginning of the window of the corresponding window state (or the position of the corresponding received baseband signal sampling point).

[0032] S150: Based on the window state with the highest similarity between the window angle difference sequence and the reference angle difference sequence, determine the synchronization position in the received baseband signal used for GFSK demodulation.

[0033] In some embodiments, before S150 (e.g., after S140), the above method may further include: for each window state, obtaining an average deviation based on the difference between the window angle difference sequence and the reference angle difference sequence. It is understood that the smaller the average deviation, the greater the similarity between the window angle difference sequence of the corresponding window state and the reference angle difference sequence. For example, an angle difference sequence can be obtained by sequentially performing angle principal value calculation and unwinding operations on the difference sequence between the window angle difference sequence and the reference angle difference sequence, and then sequentially performing angle principal value calculation, absolute value calculation, and averaging operations on the differences between each element of the angle difference sequence and its mean, thereby obtaining the average deviation. It is understood that the angle principal value calculation operation ensures that the output angle is within the range of [-pi:pi], and the unwinding operation ensures that the difference between two adjacent angles in the sequence is within the range of [-pi:pi].

[0034] For example, the average deviation can be defined as diff_std(idx) = MEAN(ABS(ANGLETRANS(diff_out(idx)–diff_mean(idx)))), where diff_out(idx) = UNWRAP(ANGLETRANS(phase_diff_win(idx)–pgfsk_diff)), and diff_mean(idx) = MEAN(diff_out(idx)), where MEAN represents the mean, ABS represents the absolute value, ANGLETRANS represents the principal angle value, and UNWRAP represents unwinding.

[0035] Based on the above embodiments, S150 may include: determining a local minimum value less than a preset threshold value in the average deviation, and determining the synchronization position based on the window state corresponding to the local minimum value. For example, the preset threshold value may be 0.4 to 0.7, preferably 0.6. As a specific embodiment, the sliding range of the sliding window (i.e., the period used to determine the local minimum value of the average deviation) may be preset, and an average deviation less than the preset threshold value may be determined within this sliding range. If multiple average deviations less than the preset threshold value exist, the minimum value among them is selected to determine the synchronization position. For example, the received baseband signal sampling point corresponding to the signal angle (in the signal angle sequence) at the beginning of the window state corresponding to the local minimum value may be used as the synchronization position.

[0036] Therefore, the signal processing method for GFSK demodulation according to embodiments of the present invention determines the synchronization position for demodulating the received signal by comparing the correlation between the received signal and the local sequence in the frequency domain. This reduces the computational complexity compared to the prior art of performing correlation peak calculation in the time domain, thereby reducing system computational costs and improving system demodulation performance.

[0037] In some embodiments, the above method may further include: obtaining a frequency offset based on the synchronization position for frequency offset compensation. As a specific embodiment, the frequency offset to be compensated can be calculated using the mean of the angle difference sequence corresponding to the window state corresponding to the synchronization position, as described above. For example, the frequency offset can be defined as Freq_offset = mean_diff(peak_idx) / 2 / pi*fsample, where peak_idx represents the synchronization position (e.g., the starting signal angle or the position of the received baseband signal sampling point corresponding to its corresponding window state), and fsample represents the chip rate.

[0038] In some embodiments, the method may further include: determining the interference caused by the preceding and following symbol sequences based on the preset synchronization word; and making a synchronization word decision by eliminating the interference based on the synchronization position. For example, the interference is caused by inter-symbol interference (ISI). This synchronization word decision scheme may be called pesudo-DFD (pseudo-decision feedback demodulation). Exemplarily, the preceding symbol sequence refers to a symbol sequence (of the same length) that lags behind the preset synchronization word by one bit, while the following symbol sequence refers to a symbol sequence (of the same length) that leads the preset synchronization word by one bit. As a specific embodiment, the interference caused by the preceding and following symbol sequences is determined using a reference phase interference value provided by a decision feedback equalizer (DFE). As a specific embodiment, the synchronization word decision is made using the mean of the window angle difference sequence and the angle difference difference sequence as described above, based on the synchronization position. Taking BLE application scenarios as an example, the interference caused by the previous symbol sequence and the next symbol sequence can be defined as AA_pre=[0(AA(1:end-1)*2–1)]*DFE_PHASE and AA_post=[(AA(2:end)*2–1)0]*DFE_PHASE, respectively. Here, [0(AA(1:end-1)*2–1)] represents the corresponding NZR code of the same length that is one bit behind the AA code, and [(AA(2:end)*2–1)0] represents the corresponding NZR code of the same length that is one bit ahead of the AA code. DFE_PHASE represents the reference phase interference value provided by DFE (the reference interference value generated by adjacent (previous / next) symbols on the current symbol in phase). The decision used to determine whether the received AA code is correct can be defined as AAcode_rx=SIGN(ANGLETRANS(phase_diff_win(pk_idx)–diff_mean(pk_idx)–AA_pre–AA_post)), where SIGN is the symbol function. Therefore, it is possible to achieve excellent decision performance with lower complexity.

[0039] Although the implementation of the pesudo-DFD scheme in the above description is based on the synchronization method (i.e., the synchronization position determined therefrom) according to the foregoing embodiments, the pesudo-DFD scheme can also be implemented independently of the above synchronization method, for example, based on other known synchronization schemes (such as time-domain-based synchronization schemes).

[0040] Accordingly, embodiments of the present invention also provide another signal processing method for GFSK demodulation, comprising: determining the interference caused by the preceding symbol sequence and the following symbol sequence according to a preset synchronization word; and making a synchronization word decision based on the synchronization position by eliminating the interference. Specific implementation details can be found in the relevant descriptions of the above-described pesudo-DFD scheme.

[0041] Figure 3 This is a schematic diagram of a signal processing apparatus for GFSK demodulation according to an embodiment of the present invention, configured to perform the signal processing method for GFSK demodulation provided in the foregoing embodiment.

[0042] like Figure 3 As shown, the signal processing device for GFSK demodulation includes a local angle sequence acquisition module 310, a reference angle differential sequence acquisition module 320, a signal angle sequence acquisition module 330, a window angle differential sequence acquisition module 340, and a synchronization position determination module 350.

[0043] The local angle sequence acquisition module 310 is configured to obtain the local angle sequence of the theoretical GFSK modulated signal based on a preset synchronization word.

[0044] In some embodiments, when the above method is specifically used for BLE, the synchronization word may be an access address.

[0045] In some embodiments, the local angle sequence acquisition module 310 may be specifically configured to: generate the theoretical GFSK modulation signal by upsampling and GFSK modulation of the synchronization word; and obtain the local angle sequence by performing angle calculation on the theoretical GFSK modulation signal.

[0046] The reference angle difference sequence acquisition module 320 is configured to obtain a reference angle difference sequence based on the local angle sequence.

[0047] In some embodiments, the reference angle difference sequence acquisition module 320 may be specifically configured to: generate a first sampled angle sequence by first downsampling the local angle sequence, wherein the first downsampling is the same multiple as the upsampling; and obtain the angle difference sequence of the first sampled angle sequence as the reference angle difference sequence.

[0048] The signal angle sequence acquisition module 330 is configured to obtain the signal angle sequence based on the received baseband signal.

[0049] In some embodiments, the signal angle sequence acquisition module 330 may be specifically configured to: generate the received baseband signal by processing the received signal, wherein the processing includes sampling with a sampling rate that is the same as the multiple of the upsampling; and obtain the signal angle sequence by performing angle calculation on the received baseband signal.

[0050] The window angle difference sequence acquisition module 340 is configured to obtain a window angle difference sequence corresponding to each window state from the signal angle sequence based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence.

[0051] In some embodiments, the window angle difference sequence acquisition module 340 may be specifically configured to: for each window state, generate a second sampled angle sequence by second downsampling the corresponding sub-sequence within the window extracted from the signal angle sequence, wherein the second downsampling is the same multiple as the upsampling; and obtain the angle difference sequence of the second sampled angle sequence as the window angle difference sequence.

[0052] The synchronization position determination module 350 is configured to determine the synchronization position in the received baseband signal used for GFSK demodulation based on the window state with the highest similarity between the window angle difference sequence and the reference angle difference sequence.

[0053] In some embodiments, the above-described apparatus may further include an average deviation acquisition module, configured to obtain an average deviation for each window state based on the difference between the window angle difference sequence and the reference angle difference sequence. For example, the average deviation acquisition module can obtain an angle difference sequence by sequentially performing angle principal value calculation and unwinding operations on the difference sequence between the window angle difference sequence and the reference angle difference sequence, and then sequentially performing angle principal value calculation, absolute value calculation, and averaging operations on the differences between each element of the angle difference sequence and its mean, thereby obtaining the average deviation.

[0054] In some embodiments, the synchronization position determination module 350 may be specifically configured to: determine a local minimum value less than a preset threshold value in the average deviation, and determine the synchronization position based on the window state corresponding to the local minimum value. For example, the preset threshold value may be 0.4 to 0.7, preferably 0.6. As a specific embodiment, the synchronization position determination module 350 may preset the sliding range of the sliding window (i.e., the period used to determine the local minimum value of the average deviation), and determine the average deviation less than the preset threshold value within this sliding range. If multiple average deviations less than the preset threshold value exist, the minimum value among them is selected to determine the synchronization position.

[0055] Therefore, the signal processing apparatus for GFSK demodulation according to embodiments of the present invention determines the synchronization position for demodulating the received signal by comparing the correlation between the received signal and the local sequence in the frequency domain, which can at least reduce the computational complexity compared with the prior art of performing correlation peak calculation in the time domain, thereby reducing the system computational cost and improving the system demodulation performance.

[0056] In some embodiments, the above-described apparatus may further include a frequency offset acquisition module configured to obtain a frequency offset based on the synchronization position for frequency offset compensation. As a specific embodiment, the frequency offset to be compensated can be calculated using the mean of the angle difference sequence corresponding to the window state corresponding to the synchronization position, as described above.

[0057] In some embodiments, the above-described apparatus may further include a decision module configured to: determine interference caused by the preceding and following symbol sequences based on the preset synchronization word; and make a synchronization word decision by eliminating the interference based on the synchronization position. In other words, the reception of the synchronization word can be determined using a pesudo-DFD (pseudo-decision feedback demodulation) method. Exemplarily, the preceding symbol sequence refers to a symbol sequence (of the same length) that lags behind the preset synchronization word by one bit, while the following symbol sequence refers to a symbol sequence (of the same length) that leads the preset synchronization word by one bit. As a specific embodiment, the interference caused by the preceding and following symbol sequences is determined using a reference phase interference value provided by a decision feedback equalizer (DFE). As a specific embodiment, the synchronization word decision is performed using the mean of the window angle difference sequence and the angle difference difference sequence as described above, based on the synchronization position. Therefore, excellent decision performance can be achieved with lower complexity.

[0058] Embodiments of the present invention also provide another signal processing apparatus for GFSK demodulation, comprising: an interference determination module configured to determine interference caused by a preceding symbol sequence and a following symbol sequence based on a preset synchronization word; and a synchronization word decision module configured to make a synchronization word decision based on the synchronization position by eliminating the interference. Specific implementation details can be found in the aforementioned description of the pesudo-DFD scheme.

[0059] Embodiments of the present invention also provide a receiver including a signal processing device for GFSK demodulation according to the foregoing embodiments. Exemplarily, the signal processing device for GFSK demodulation may be a baseband circuit in the receiver.

[0060] Figure 4 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention, such as... Figure 4 As shown, the electronic device includes a processor 410, a storage device 420, and a communication device 430; the number of processors 410 in the electronic device can be one or more. Figure 4 Taking a processor 410 as an example; the processor 410, storage device 420, and communication device 430 in an electronic device can be connected via a bus or other means. Figure 4 Taking the example of a connection between China and Israel via a bus.

[0061] Storage device 420, as a computer-readable storage medium, can be used to store software programs, computer-executable programs, and modules, such as the modules corresponding to the signal processing method for GFSK demodulation in this embodiment of the invention (e.g., the local angle sequence acquisition module 310, the reference angle differential sequence acquisition module 320, the signal angle sequence acquisition module 330, the window angle differential sequence acquisition module 340, and the synchronization position determination module 350 in the signal processing device for GFSK demodulation). Processor 410 executes various functional applications and data processing of the electronic device by running the software programs, instructions, and modules stored in storage device 420, thereby implementing the aforementioned signal processing method for GFSK demodulation.

[0062] Storage device 420 may primarily include a program storage area and a data storage area. The program storage area may store the operating system and at least one application program required for a given function; the data storage area may store data created based on terminal usage. Furthermore, storage device 420 may include high-speed random access memory and non-volatile memory, such as at least one disk storage device, flash memory, or other non-volatile solid-state storage device. In some instances, storage device 420 may further include memory remotely located relative to processor 410, which can be connected to electronic devices via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0063] Communication device 430 is used to enable network connection or mobile data connection between servers.

[0064] The electronic device provided in this embodiment can be used to execute the signal processing method for GFSK demodulation provided in the above embodiment, and has the corresponding functions and beneficial effects.

[0065] This invention also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements a signal processing method for GFSK demodulation according to any embodiment of the invention. The method specifically includes: obtaining a local angle sequence of a theoretical GFSK modulated signal based on a preset synchronization word; obtaining a reference angle difference sequence based on the local angle sequence; obtaining a signal angle sequence based on a received baseband signal; obtaining a window angle difference sequence corresponding to each window state from the signal angle sequence based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence; and determining a synchronization position for GFSK demodulation in the received baseband signal based on the window state with the highest similarity to the reference angle difference sequence; or the method specifically includes: determining interference caused by the previous symbol sequence and the next symbol sequence according to a preset synchronization word; and making a synchronization word decision based on the synchronization position by eliminating the interference.

[0066] Of course, the computer-executable instructions provided in the embodiments of the present invention are not limited to the method operations described above, but can also perform related operations in the signal processing method for GFSK demodulation provided in any embodiment of the present invention.

[0067] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause an electronic device (which may be a personal computer, server, or network device, etc.) to execute the methods described in the various embodiments of the present invention.

[0068] It is worth noting that in the above embodiments of the signal processing device for GFSK demodulation, the various units and modules included are only divided according to functional logic, but are not limited to the above division, as long as the corresponding functions can be achieved; in addition, the specific names of each functional unit are only for easy differentiation and are not used to limit the scope of protection of the present invention.

[0069] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. For those skilled in the art, the present invention can be modified and varied in various ways. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principle of the present invention should be included within the scope of protection of the present invention.

Claims

1. A signal processing method for GFSK demodulation, comprising: S110. Obtain the local angle sequence of the theoretical GFSK modulated signal based on the preset synchronization word; S120. Obtain a reference angle difference sequence based on the local angle sequence; S130. Obtain the signal angle sequence based on the received baseband signal; S140. Based on the sliding window, a window angle difference sequence corresponding to each window state is obtained from the signal angle sequence, wherein the size of the sliding window is determined by the length of the local angle sequence. as well as S150. Based on the window state with the highest similarity between the window angle difference sequence and the reference angle difference sequence, determine the synchronization position in the received baseband signal used for GFSK demodulation. Prior to S150, the signal processing method for GFSK demodulation further includes: For each window state, an average deviation is obtained based on the difference between the window angle difference sequence and the reference angle difference sequence. This is achieved by sequentially performing angle principal value calculation and unwinding operations on the difference sequence between the window angle difference sequence and the reference angle difference sequence to obtain an angle difference sequence. Then, the average deviation is obtained by sequentially performing angle principal value calculation, absolute value calculation, and averaging operations on the difference between each element of the angle difference sequence and its mean. The S150 includes: determining a local minimum value less than a preset threshold value in the average deviation, and determining the synchronization position based on the window state corresponding to the local minimum value.

2. The signal processing method for GFSK demodulation according to claim 1, wherein S110 includes: The theoretical GFSK modulated signal is generated by upsampling the synchronization word and performing GFSK modulation. as well as The local angle sequence is obtained by performing angle calculations on the theoretical GFSK modulated signal.

3. The signal processing method for GFSK demodulation according to claim 2, wherein S120 includes: A first sampled angle sequence is generated by first downsampling the local angle sequence, wherein the first downsampling is the same multiple as the upsampling; as well as The angle difference sequence of the first sampled angle sequence is obtained as the reference angle difference sequence.

4. The signal processing method for GFSK demodulation according to claim 2, wherein S130 includes: The received baseband signal is generated by processing the received signal, wherein the processing includes a sampling operation with a sampling rate that is the same as the multiple of the upsampling. as well as The signal angle sequence is obtained by performing angle calculations on the received baseband signal.

5. The signal processing method for GFSK demodulation according to claim 2, wherein S140 includes: For each window state, a second sampling angle sequence is generated by second downsampling the corresponding subsequence within the window extracted from the signal angle sequence, wherein the second downsampling is the same multiple as the upsampling; and The angle difference sequence of the second sampling angle sequence is obtained as the window angle difference sequence.

6. The signal processing method for GFSK demodulation according to claim 1, wherein the preset threshold value is 0.4 to 0.

7.

7. A signal processing method for GFSK demodulation, comprising: The interference caused by the previous symbol sequence and the next symbol sequence is determined based on the preset synchronization word; as well as Synchronization word decision is made by eliminating the interference based on a predetermined synchronization position, wherein the synchronization position is determined by the signal processing method for GFSK demodulation as described in claim 1.

8. The signal processing method for GFSK demodulation according to claim 7, wherein the interference caused by the preceding symbol sequence and the following symbol sequence is determined using a reference phase interference value provided by a decision feedback equalizer (DFE).

9. The signal processing method for GFSK demodulation according to claim 7, wherein a synchronization word decision is made using the mean of a window angle difference sequence and an angle difference difference sequence obtained based on the synchronization position, wherein the window size of the window angle difference sequence is determined by the length of a local angle sequence based on the preset synchronization word, and the angle difference difference sequence is obtained by the difference between the window angle difference sequence and a reference angle difference sequence based on the local angle sequence.

10. A signal processing apparatus for GFSK demodulation, comprising: The local angle sequence acquisition module is configured to obtain the local angle sequence of the theoretical GFSK modulated signal based on a preset synchronization word; A reference angle difference sequence acquisition module is configured to obtain a reference angle difference sequence based on the local angle sequence; A signal angle sequence acquisition module is configured to acquire a signal angle sequence based on the received baseband signal. A window angle difference sequence acquisition module is configured to obtain a window angle difference sequence corresponding to each window state from the signal angle sequence based on a sliding window, wherein the size of the sliding window is determined by the length of the local angle sequence; and The synchronization position determination module is configured to determine the synchronization position in the baseband signal used for GFSK demodulation based on the window state with the highest similarity between the window angle difference sequence and the reference angle difference sequence. The signal processing device for GFSK demodulation further includes an average deviation acquisition module, configured to obtain the average deviation for each window state based on the difference between the window angle difference sequence and the reference angle difference sequence. This is achieved by sequentially performing angle principal value calculation and unwinding operations on the difference sequence between the window angle difference sequence and the reference angle difference sequence to obtain an angle difference sequence. Then, the average deviation is obtained by sequentially performing angle principal value calculation, absolute value calculation, and averaging operations on the differences between each element of the angle difference sequence and its mean. The synchronization position determination module is configured to: determine a local minimum value less than a preset threshold value in the average deviation, and determine the synchronization position based on the window state corresponding to the local minimum value.

11. A signal processing apparatus for GFSK demodulation, comprising: An interference determination module is configured to determine the interference caused by the previous symbol sequence and the next symbol sequence based on a preset synchronization word. as well as The synchronization word decision module performs synchronization word decision by eliminating the interference based on a predetermined synchronization position, wherein the synchronization position is determined by the signal processing method for GFSK demodulation as described in claim 1.

12. The signal processing apparatus for GFSK demodulation according to claim 11, wherein the interference caused by the preceding symbol sequence and the following symbol sequence is determined using a reference phase interference value provided by a decision feedback equalizer (DFE).

13. The signal processing method for GFSK demodulation according to claim 11, wherein a synchronization word decision is made using the mean of a window angle difference sequence and an angle difference difference sequence obtained based on the synchronization position, wherein the window size of the window angle difference sequence is determined by the length of a local angle sequence based on the preset synchronization word, and the angle difference difference sequence is obtained by the difference between the window angle difference sequence and a reference angle difference sequence based on the local angle sequence.

14. A receiver comprising the signal processing apparatus for GFSK demodulation according to claim 10 or 11.

15. An electronic device comprising a processor and a storage device, wherein the storage device stores program instructions that, when executed by the processor, cause the electronic device to perform the signal processing method for GFSK demodulation according to claim 1 or 7.

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