Frequency offset correction method and apparatus, electronic device, and readable storage medium

Abstract

The present disclosure provides a frequency offset correction method, device, electronic equipment and readable storage medium. The method comprises receiving a modulated first baseband signal, demodulating the modulated first baseband signal to obtain a second baseband signal, wherein the second baseband signal comprises a first received signal and a second received signal; based on a first matched filter, matching the first received signal with a locally stored spread spectrum signal to obtain a first output signal; and based on a second matched filter, matching the second received signal with the locally stored spread spectrum signal to obtain a second output signal; determining a frequency offset and a time offset based on a peak value of the first output signal and a peak value of the second output signal; and performing frequency offset compensation on the second baseband signal based on the frequency offset and the time offset. The present disclosure correctly calculates the frequency deviation and has low algorithm complexity, thereby improving the reliability of the system.

Description

Technical Field

[0001] This disclosure relates to the field of communication technology, and in particular to a frequency offset correction method, apparatus, electronic device, and readable storage medium. Background Technology

[0002] With the development of communication technology, communication technology is gradually moving towards high-speed and long-distance wireless communication. However, as the communication rate increases, the interference from nature under wireless channel conditions will become stronger. For communication systems, due to the frequency difference between the transmitting end and the receiving end, as well as the Doppler frequency shift caused by the movement of the receiving end, there is a frequency offset between the carrier frequency and the local crystal oscillator frequency, which is simply called "frequency offset". It is necessary to correct the frequency offset to eliminate communication interference.

[0003] Existing technologies provide some frequency offset estimation and correction methods, but these methods suffer from inaccurate frequency offset estimation or high algorithm complexity, leading to a decrease in receiver performance. Summary of the Invention

[0004] This disclosure is made in view of the above-mentioned problems. This disclosure provides a frequency offset correction method, apparatus, electronic device, and readable storage medium.

[0005] According to one aspect of this disclosure, a frequency offset correction method is provided for use in a spread spectrum communication system, comprising: receiving a modulated first baseband signal; demodulating the modulated first baseband signal to obtain a second baseband signal, wherein the second baseband signal includes a first received signal and a second received signal; matching the first received signal with a locally stored spread spectrum signal based on a first matched filter to obtain a first output signal; and matching the second received signal with a locally stored spread spectrum signal based on a second matched filter to obtain a second output signal; determining a frequency offset and a time offset based on the peak value of the first output signal and the peak value of the second output signal; and performing frequency offset compensation on the second baseband signal based on the frequency offset and the time offset.

[0006] Furthermore, according to one aspect of the frequency offset correction method of this disclosure, receiving a modulated first baseband signal, demodulating the modulated first baseband signal, and obtaining a second baseband signal includes: performing quadrature demodulation on the radio frequency signal and performing down-conversion processing to obtain the second baseband signal; wherein the radio frequency signal is generated by sequentially performing chirped spread spectrum modulation, quadrature modulation, and up-conversion on the first baseband signal.

[0007] Furthermore, according to one aspect of the frequency offset correction method of this disclosure, a first received signal is matched with a locally stored spread spectrum signal based on a first matched filter to obtain a first output signal; and a second received signal is matched with a locally stored spread spectrum signal based on a second matched filter to obtain a second output signal, comprising: the locally stored spread spectrum signal is a chirped spread spectrum signal, the chirped spread spectrum signal including a first spread spectrum signal and a second spread spectrum signal; the first spread spectrum signal is correlated with the first received signal to obtain the first output signal; the second spread spectrum signal is correlated with the second received signal to obtain the second output signal; wherein the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

[0008] Furthermore, according to one aspect of the frequency offset correction method of this disclosure, determining the frequency offset and time offset based on the peak value of the first output signal and the peak value of the second output signal includes:

[0009] Perform Fast Fourier Transform on the first and second output signals respectively to obtain the peak value of the first and second output signals. Based on the peak value of the first and second output signals, obtain the frequency offset and frequency deviation.

[0010] According to another aspect of this disclosure, a frequency offset correction apparatus is provided, comprising: a received signal acquisition unit configured to receive a modulated first baseband signal, demodulate the modulated first baseband signal, and acquire a second baseband signal, wherein the second baseband signal includes a first received signal and a second received signal; an output signal acquisition unit configured to match the first received signal with a locally stored spread spectrum signal based on a first matched filter to acquire a first output signal; and to match the second received signal with a locally stored spread spectrum signal based on a second matched filter to acquire a second output signal; a processing unit configured to determine a frequency offset and a time offset based on the peak value of the first output signal and the peak value of the second output signal; and a correction unit configured to perform frequency offset compensation on the second baseband signal based on the frequency offset and the time offset.

[0011] According to another aspect of the frequency offset correction device of this disclosure, the receiving signal acquisition unit is further configured to: at the transmitting end, sequentially perform chirped spread spectrum modulation and quadrature modulation on the first baseband signal; perform up-conversion processing on the modulated first baseband signal to form a radio frequency signal and transmit it into the air; at the receiving end, perform quadrature demodulation on the radio frequency signal and perform down-conversion processing to acquire the second baseband signal.

[0012] According to another aspect of the frequency offset correction apparatus of this disclosure, the output signal acquisition unit is further configured to: store locally a chirped spread spectrum signal, the chirped spread spectrum signal including a first spread spectrum signal and a second spread spectrum signal; perform correlation processing on the first spread spectrum signal and a first received signal to acquire a first output signal; and perform correlation processing on the second spread spectrum signal and a second received signal to acquire a second output signal; wherein the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

[0013] According to another aspect of the frequency offset correction apparatus of this disclosure, the processing unit is further configured as follows:

[0014] Perform Fast Fourier Transform on the first and second output signals respectively to obtain the peak values ​​of the first and second output signals. Based on the peak values ​​of the first and second output signals, determine the frequency offset and time offset.

[0015] According to another aspect of this disclosure, an electronic device is provided, comprising: a memory for storing computer-readable instructions; and a processor for executing the computer-readable instructions, causing the electronic device to perform the frequency offset correction method as described above.

[0016] According to another aspect of this disclosure, a readable storage medium is provided for storing computer-readable instructions that, when executed by a processor, cause the processor to perform the frequency offset correction method as described above.

[0017] As will be described in detail below, the frequency offset correction method, apparatus, electronic device, and readable storage medium according to embodiments of the present disclosure employ a dual matched filter at the receiving end, capture the signal using locally stored spread spectrum signal, estimate the frequency offset and time offset, and perform frequency offset compensation on the received baseband signal to ensure correct demodulation of the information at the receiving end and improve the stability of the spread spectrum communication system. In addition, chirped spread spectrum technology is used at the transmitting end to modulate the transmitted baseband signal, and the autocorrelation characteristics of the chirped signal are utilized at the receiving end to correctly calculate the frequency offset with low algorithm complexity. The result is fed back to the spread spectrum communication system for frequency offset compensation and then demodulated, thereby improving the reliability of the system.

[0018] It should be understood that both the foregoing general description and the following detailed description are exemplary and intended to provide further illustration of the claimed technology. Attached Figure Description

[0019] The above and other objects, features, and advantages of this disclosure will become more apparent from the more detailed description of the embodiments thereof in conjunction with the accompanying drawings. The drawings are provided to further illustrate the embodiments of this disclosure and form part of the specification. They are used together with the embodiments of this disclosure to explain the disclosure and do not constitute a limitation thereof. In the drawings, the same reference numerals generally represent the same components or steps.

[0020] Figure 1 This is a schematic diagram of a spread spectrum communication system according to an embodiment of the present disclosure.

[0021] Figure 2 This is a flowchart illustrating a frequency offset correction method according to an embodiment of the present disclosure.

[0022] Figure 3 This is a schematic diagram illustrating the capture principle of a dual matched filter according to an embodiment of the present disclosure.

[0023] Figure 4 This is a schematic diagram illustrating the P-path and Q-path without frequency offset and time deviation according to an embodiment of the present disclosure.

[0024] Figure 5 This is a schematic diagram illustrating frequency offset in the P-path and Q-path according to an embodiment of the present disclosure.

[0025] Figure 6 This is a schematic diagram illustrating a time deviation between the P-path and Q-path according to an embodiment of the present disclosure.

[0026] Figure 7 This is a schematic diagram illustrating frequency offset and time deviation of the P-path and Q-path according to an embodiment of the present disclosure.

[0027] Figure 8 This is a functional block diagram of a frequency offset correction device according to an embodiment of the present disclosure.

[0028] Figure 9 This is a hardware block diagram illustrating an electronic device according to an embodiment of the present disclosure.

[0029] Figure 10 This is a schematic diagram illustrating a readable storage medium according to an embodiment of the present disclosure. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of this disclosure more apparent, exemplary embodiments according to this disclosure will now be described in detail with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this disclosure, and not all embodiments of this disclosure. It should be understood that this disclosure is not limited to the exemplary embodiments described herein.

[0031] First, refer to Figure 1 and Figure 2This invention describes a spread spectrum communication system and a frequency offset correction method according to embodiments of the present disclosure. Figure 1 This is a schematic diagram of a spread spectrum communication system according to an embodiment of the present disclosure. Figure 2 This is a flowchart illustrating a frequency offset correction method according to an embodiment of the present disclosure.

[0032] like Figure 1 As shown, the spread spectrum communication system 100 includes a transmitter 101 and a receiver 102. The transmitter 101 serves as the transmitting end for signal transmission, and the receiver 102 serves as the receiving end for signal reception. The signal can be transmitted wirelessly from the transmitter 101 to the receiver 102.

[0033] Specifically, the main task of a transmitter circuit is to modulate a useful low-frequency signal onto a high-frequency carrier, transforming it into an electromagnetic wave with a certain bandwidth at a specific center frequency, suitable for transmission through an antenna. It is widely used in various civilian and military equipment such as television, radio, and radar. It can be mainly divided into several types, including FM transmitters, AM transmitters, and optical transmitters.

[0034] A receiver receives electromagnetic signals from an antenna and sends them to the receiver. An ideal receiver suppresses all unwanted noise, including other signals, and does not add any noise or interference to the desired signal. Regardless of the signal's form or format, it can be transformed to suit the characteristics required by the signal processor's detection circuitry before being sent to the intelligent user interface.

[0035] The embodiments disclosed herein do not limit the specific device types of the transmitter and receiver.

[0036] Figure 2 This is a flowchart of a frequency offset correction method according to an embodiment of the present disclosure, which is applied to the spread spectrum communication system described above.

[0037] like Figure 2 As shown, the frequency offset correction method includes the following steps:

[0038] In step S201, the modulated first baseband signal is received, the modulated first baseband signal is demodulated, and a second baseband signal is obtained, wherein the second baseband signal includes a first received signal and a second received signal.

[0039] In the embodiments of this disclosure, the first baseband signal refers to the original electrical signal emitted by the source (information source, also known as the transmitter) without modulation (spectral shifting and transformation). Its characteristics include a low frequency, a signal spectrum starting near zero frequency, and a low-pass form. Based on the characteristics of the original electrical signal, baseband signals can be divided into digital baseband signals and analog baseband signals (correspondingly, information sources are also divided into digital information sources and analog information sources). This is determined by the information source. In simpler terms, a baseband signal is the signal that directly expresses the information to be transmitted; for example, the sound waves from our speech are baseband signals.

[0040] Specifically, at the transmitting end, the first baseband signal is sequentially subjected to chirped spread spectrum modulation and quadrature modulation; the modulated first baseband signal is up-converted to form a radio frequency signal and transmitted into the air; at the receiving end, the radio frequency signal propagating from the air is received, and the radio frequency signal is quadrature demodulated and down-converted to obtain the second baseband signal.

[0041] Chirp Spread Spectrum (CSS), also known as linear frequency modulation spread spectrum, is a spread spectrum technique used in digital communications. CSS technology can improve the performance and range of wireless communication, enabling wireless communication over longer distances than modulation techniques such as FSK (Frequency Shift Keying).

[0042] Specifically, the first baseband signal is subjected to chirped spread spectrum modulation to obtain a chirped spread spectrum signal (CSS signal), which is a linear frequency modulated signal. The mathematical expression is as follows:

[0043]

[0044] In the formula This represents a square wave signal, where T is the duration of the linear frequency modulated signal, f0 is the center frequency, φ0 is the initial phase of the signal, and μ is the modulation rate, which also determines the sweep direction. A positive sign indicates a linear increase in frequency, known as up-chirp, while a negative sign indicates down-chirp.

[0045] The first baseband signal, after chirped spread spectrum modulation, is then subjected to quadrature modulation (IQ modulation) and up-conversion to form a radio frequency (RF) signal, which is then transmitted into the air. The RF signal transmitted into the air can be represented as:

[0046]

[0047] In the formula f Lo f is the local oscillator frequency. IF f0 is the intermediate frequency, and f0 is the center frequency.

[0048] At the receiving end, the radio frequency signal is received from the air, and after quadrature demodulation, it is downconverted to the second baseband signal. Since there is a delay and offset in the transmission process, this delay and offset are caused by a variety of reasons, such as Doppler frequency shift caused by the movement of the receiving end.

[0049] The second baseband signal includes a first received signal and a second received signal, meaning that the signal is down-converted to obtain two signals, such as... Figure 3 As shown, they are denoted as P-path and Q-path, respectively. The signal in P-path is denoted as the first received signal, and the signal in Q-path is denoted as the second received signal.

[0050] The final received second baseband signal can be represented as follows:

[0051]

[0052] in:

[0053] The signal in the P-path is as follows:

[0054] The signal in the Q path is as follows:

[0055]

[0056] In the formula, Δt and Δf represent time offset and frequency offset, respectively.

[0057] In step S202, based on the first matched filter, the first received signal is matched with the locally stored spread spectrum signal to obtain the first output signal; and based on the second matched filter, the second received signal is matched with the locally stored spread spectrum signal to obtain the second output signal.

[0058] like Figure 3 As shown, in the embodiments of this disclosure, the receiving end uses two matching circuits, referred to as the first matched filter and the second matched filter, respectively, for capturing signals at the receiving end.

[0059] Specifically, the locally stored spread spectrum signal is a chirped spread spectrum signal, which includes a first spread spectrum signal and a second spread spectrum signal. The first spread spectrum signal is correlated with the first received signal to obtain a first output signal, and the second spread spectrum signal is correlated with the second received signal to obtain a second output signal.

[0060] Among them, the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

[0061] Specifically, the spread spectrum sequence of the locally stored chirped spread spectrum signal is the same as that of the transmitter. Based on the good autocorrelation characteristics of the chirped spread spectrum signal, the outputs of the two matched filters are as follows:

[0062]

[0063]

[0064] Where P(t) is denoted as the first output signal and Q(t) is denoted as the second output signal.

[0065] In step S203, frequency offset and time offset are determined based on the peak value of the first output signal and the peak value of the second output signal.

[0066] In the embodiments of this disclosure, the first output signal and the second output signal are subjected to fast Fourier transform respectively to obtain the peak value of the first output signal and the peak value of the second output signal, and the frequency offset and frequency deviation are obtained based on the peak value of the first output signal and the peak value of the second output signal.

[0067] Performing a Fast Fourier Transform on the P and Q signals reveals the peak values ​​of the P and Q signals in the frequency domain as follows:

[0068]

[0069]

[0070] In the formula, Δt and Δf represent time offset and frequency offset, respectively.

[0071] The detection results for P-channel and Q-channel signals can be referenced. Figures 4-7 .in, Figure 4 It has no frequency offset and no time deviation (referred to as time offset). Figure 5 Because of frequency offset, Figure 6 Due to time discrepancies, Figure 7 This means that there is both frequency offset and time deviation.

[0072] Specifically, signal detection thresholds are determined by both P and Q paths. If F P (f) and F Q (f) If both signals are greater than the preset detection threshold CAD_Thr at the same time, the receiver is considered to have successfully detected the signal, that is, the signal acquisition is successful, and the receiver continues to receive subsequent signals; otherwise, the signal detection is considered to have failed, that is, the signal acquisition has failed, and the receiver stops working.

[0073] When signal detection is successful, based on the peak value relationship between P and Q channels and time-frequency symmetry, we can conclude that:

[0074]

[0075] Δt=(F P Max+F Q Max)×μ / f s

[0076] In the formula F P Max and F Q Max represents the peak positions of P and Q paths, f s Indicates the sampling frequency.

[0077] In step S204, frequency offset compensation is performed on the second baseband signal based on frequency offset and time offset.

[0078] In the embodiments of this disclosure, Δf and Δt are fed back to the second baseband signal, and the frequency offset step size of the second baseband signal is adjusted to ensure that the data is demodulated correctly.

[0079] The frequency offset correction method according to embodiments of the present disclosure has been described above. The frequency offset correction apparatus for implementing the frequency offset correction method will now be further described. Figure 8 This is a functional block diagram of a frequency offset correction device according to an embodiment of the present disclosure.

[0080] like Figure 8 As shown, the frequency offset correction device 800 according to an embodiment of this disclosure includes a received signal acquisition unit 801, an output signal acquisition unit 802, a processing unit 803, and a correction unit 804. Those skilled in the art will readily understand that these unit modules can be implemented individually in hardware, individually in software, or in combination thereof in various ways, and this disclosure is not limited to any one of them.

[0081] Specifically, the receiving signal acquisition unit 801 is configured to receive the modulated first baseband signal, demodulate the modulated first baseband signal, and acquire the second baseband signal, wherein the second baseband signal includes the first received signal and the second received signal.

[0082] The output signal acquisition unit 802 is configured to match a first received signal with a locally stored spread spectrum signal based on a first matched filter to acquire a first output signal; and to match a second received signal with a locally stored spread spectrum signal based on a second matched filter to acquire a second output signal.

[0083] The processing unit 803 is configured to determine the frequency offset and time offset based on the peak value of the first output signal and the peak value of the second output signal.

[0084] The correction unit 804 is configured to perform frequency offset compensation on the second baseband signal based on the frequency offset value.

[0085] Specifically, the receiving signal acquisition unit 801 is further configured to: perform quadrature demodulation on the radio frequency signal and perform down-conversion processing to acquire the second baseband signal; wherein the radio frequency signal is generated by sequentially performing chirped spread spectrum modulation, quadrature modulation and up-conversion on the first baseband signal.

[0086] Specifically, the output signal acquisition unit 802 is further configured to: store locally a chirped spread spectrum signal, which includes a first spread spectrum signal and a second spread spectrum signal; perform correlation processing on the first spread spectrum signal and a first received signal to obtain a first output signal; and perform correlation processing on the second spread spectrum signal and a second received signal to obtain a second output signal; wherein the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

[0087] Specifically, the processing unit 803 is further configured to: perform fast Fourier transform on the first output signal and the second output signal respectively to obtain the peak value of the first output signal and the peak value of the second output signal, and determine the frequency offset and time offset based on the peak value of the first output signal and the peak value of the second output signal.

[0088] Figure 9 The illustrated electronic device 900 specifically includes a central processing unit (CPU) 901, a graphics processing unit (GPU) 902, and a main memory 903. These units are interconnected via a bus 904. The CPU 901 and / or GPU 902 can function as the aforementioned processor, and the main memory 903 can function as the aforementioned memory storing computer-readable instructions. Furthermore, the electronic device 900 may also include a communication unit 905, a storage unit 906, an output unit 907, an input unit 908, and an external device 909, all of which are also connected to the bus 904.

[0089] Figure 10 This is a schematic diagram illustrating a readable storage medium according to an embodiment of the present disclosure. Figure 10 As shown, a readable storage medium 1000 according to an embodiment of the present disclosure stores computer-readable instructions 1001 thereon. When the computer-readable instructions 1001 are executed by a processor, the frequency offset correction method according to an embodiment of the present disclosure described with reference to the above figures is performed. The computer-readable storage medium includes, but is not limited to, volatile memory and / or non-volatile memory. Volatile memory may include, for example, random access memory (RAM) and / or cache memory. Non-volatile memory may include, for example, read-only memory (ROM), hard disk, flash memory, optical disk, magnetic disk, etc.

[0090] According to the frequency offset correction method, apparatus, electronic device, and readable storage medium of the present disclosure, at the receiving end, a dual matched filter is used to capture the signal using locally stored spread spectrum signal, the frequency offset and time offset are estimated, and frequency offset compensation is performed on the received baseband signal to ensure correct demodulation of the information at the receiving end and improve the stability of the spread spectrum communication device. In addition, at the transmitting end, chirped spread spectrum technology is used to modulate the transmitted baseband signal, and at the receiving end, the autocorrelation characteristics of the chirped signal are used to correctly calculate the frequency offset with low algorithm complexity. The result is fed back to the spread spectrum communication device for frequency offset compensation and then demodulated, thereby improving the reliability of the device.

[0091] The above description of the disclosed aspects is provided to enable any person skilled in the art to make or use this disclosure. Various modifications to these aspects will be readily apparent to those skilled in the art, and the general principles defined herein may be applied to other aspects without departing from the scope of this disclosure. Therefore, this disclosure is not intended to be limited to the aspects shown herein, but rather to be carried out within the widest scope consistent with the principles and novel features disclosed herein.

[0092] The above description has been given for purposes of illustration and description. Furthermore, this description is not intended to limit the embodiments of this disclosure to the forms disclosed herein. Although numerous exemplary aspects and embodiments have been discussed above, those skilled in the art will recognize certain variations, modifications, alterations, additions, and sub-combinations therein.

Claims

1. A frequency offset correction method, applied to a spread spectrum communication system, characterized in that, include: The modulated first baseband signal is received, and the modulated first baseband signal is demodulated to obtain a second baseband signal, wherein the second baseband signal includes a first received signal and a second received signal; Based on the first matched filter, the first received signal is matched with the locally stored spread spectrum signal to obtain the first output signal; and Based on the second matched filter, the second received signal is matched with the locally stored spread spectrum signal to obtain the second output signal; Based on the peak values ​​of the first output signal and the second output signal, the frequency offset and time offset are determined; Based on the frequency offset and the time offset, frequency offset compensation is performed on the second baseband signal.

2. The frequency offset correction method according to claim 1, characterized in that, The process of receiving the modulated first baseband signal, demodulating the modulated first baseband signal, and obtaining the second baseband signal includes: The radio frequency signal is quadrature demodulated and down-converted to obtain the second baseband signal; The radio frequency signal is generated by sequentially performing chirped spread spectrum modulation, quadrature modulation, and up-conversion on the first baseband signal.

3. The frequency offset correction method according to claim 1, characterized in that, The first received signal is matched with the locally stored spread spectrum signal based on the first matched filter to obtain the first output signal; And based on the second matched filter, the second received signal is matched with the locally stored spread spectrum signal to obtain the second output signal, including: The locally stored spread spectrum signal is a chirped spread spectrum signal, which includes a first spread spectrum signal and a second spread spectrum signal. The first spread spectrum signal is correlated with the first received signal to obtain the first output signal, and the second spread spectrum signal is correlated with the second received signal to obtain the second output signal. Wherein, the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

4. The frequency offset correction method according to claim 1, characterized in that, Determining the frequency offset and time offset based on the peak values ​​of the first output signal and the second output signal includes: Perform Fast Fourier Transform on the first output signal and the second output signal respectively to obtain the peak value of the first output signal and the peak value of the second output signal. Based on the peak value of the first output signal and the peak value of the second output signal, obtain the frequency offset and frequency deviation.

5. A frequency offset correction device, characterized in that, include: The receiving signal acquisition unit is configured to receive a modulated first baseband signal, demodulate the modulated first baseband signal, and acquire a second baseband signal, wherein the second baseband signal includes a first received signal and a second received signal. The output signal acquisition unit is configured to match the first received signal with a locally stored spread spectrum signal based on a first matched filter to acquire a first output signal; and to match the second received signal with a locally stored spread spectrum signal based on a second matched filter to acquire a second output signal. The processing unit is configured to determine the frequency offset and time offset based on the peak value of the first output signal and the peak value of the second output signal; The correction unit is configured to perform frequency offset compensation on the second baseband signal based on the frequency offset and the time offset.

6. The frequency offset correction device according to claim 5, characterized in that, The received signal acquisition unit is further configured to: The radio frequency signal is quadrature demodulated and down-converted to obtain the second baseband signal; The radio frequency signal is generated by sequentially performing chirped spread spectrum modulation, quadrature modulation, and up-conversion on the first baseband signal.

7. The frequency offset correction device according to claim 5 or 6, characterized in that, The output signal acquisition unit is further configured to: The locally stored spread spectrum signal is a chirped spread spectrum signal, which includes a first spread spectrum signal and a second spread spectrum signal. The first spread spectrum signal is correlated with the first received signal to obtain the first output signal, and the second spread spectrum signal is correlated with the second received signal to obtain the second output signal. Wherein, the first spread spectrum signal and the second spread spectrum signal are conjugate complex signals.

8. The frequency offset correction device according to claim 5, characterized in that, The processing unit is further configured to: Perform Fast Fourier Transform on the first output signal and the second output signal respectively to obtain the peak value of the first output signal and the peak value of the second output signal. Based on the peak value of the first output signal and the peak value of the second output signal, determine the frequency offset and the time offset.

9. An electronic device, characterized in that, include: Memory, used to store computer-readable instructions; as well as A processor for executing the computer-readable instructions, causing the electronic device to perform the frequency offset correction method as described in any one of claims 1 to 4.

10. A readable storage medium for storing computer-readable instructions, characterized in that, When the computer-readable instructions are executed by a processor, the processor performs the frequency offset correction method as described in any one of claims 1 to 4.

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