Signal synchronization method and device

Abstract

The present invention discloses a signal synchronization method, which includes the following contents: receiving an input signal; wherein the input signal includes a PN sequence; performing a preliminary angular frequency deviation estimation on the input signal and calculating the phase angles of multiple PN sequences respectively; when the angular frequency deviation of the input signal is less than or equal to a preset angular frequency deviation threshold, accumulating the phase angles of multiple PN sequences to calculate the angular frequency deviation; when the angular frequency deviation of the input signal is greater than the preset angular frequency deviation threshold, calculating the average value of the phase angles of multiple PN sequences to calculate the angular frequency deviation; adjusting the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization, and by calculating and correcting the angular frequency deviation, the positioning accuracy of the ranging and positioning system can be significantly improved. The time delay error caused by the angular frequency deviation can be effectively compensated, which is helpful to improve the demodulation quality of the signal, reduce the bit error rate, and thus improve the measurement accuracy of the system. The present invention also discloses a signal synchronization device.

Description

Technical Field

[0001] The present invention relates to the technical field of communication signal processing, and in particular to a signal synchronization method and device. Background Art

[0002] With the development of wireless communication technology, ranging and positioning systems are increasingly used in navigation, mobile communications, the Internet of Things and other fields. However, in these systems, due to the inherent frequency deviation (frequency deviation) and phase deviation (phase deviation) between the transmitter and the receiver, the time delay of the received signal is difficult to measure accurately, thus affecting the positioning accuracy.

[0003] Traditional methods for solving frequency deviation mainly focus on improving the accuracy of the clock to reduce the impact of frequency deviation. However, after the introduction of high-precision clocks, frequency deviation and phase deviation still exist, and during the long-term operation of the device, the stability of the clock will change due to factors such as temperature drift and aging effects. For example, as the device runs for a long time, the temperature of the high-precision clock itself and the temperature of its operating environment will increase, the crystal oscillator stability of the high-precision clock will decrease, and the frequency deviation and phase deviation will gradually increase. Therefore, relying solely on high-precision clocks cannot solve the frequency deviation and phase deviation problems in signal synchronization. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a signal synchronization method and device.

[0005] The technical solution adopted by the present invention is:

[0006] The first aspect of the present application provides a signal synchronization method, which is applied to a synchronization device and includes the following contents:

[0007] Receiving an input signal; wherein the input signal at least includes a PN sequence;

[0008] Perform preliminary angular frequency deviation estimation on the input signal and calculate phase angles of multiple PN sequences respectively;

[0009] When the angular frequency deviation of the input signal is less than or equal to the preset angular frequency deviation threshold, the phase angles of multiple PN sequences are accumulated to calculate the angular frequency deviation; when the angular frequency deviation of the input signal is greater than the preset angular frequency deviation threshold, the average value of the phase angles of multiple PN sequences is calculated to calculate the angular frequency deviation;

[0010] The frequency of the input signal is adjusted according to the calculated angular frequency deviation to achieve signal synchronization.

[0011] Preferably, the receiving of the input signal includes the following:

[0012] Receiving an input signal, wherein the input signal includes a PN sequence and a chirp sequence;

[0013] Calculate the proportion of the PN sequence and the chirp sequence in the signal period; if the proportion of the PN sequence and the chirp sequence in the signal period is greater than the preset proportion threshold, execute the next step; if the proportion of the PN sequence and the chirp sequence in the signal period is less than or equal to the preset proportion threshold, do not correct the frequency deviation of the input signal.

[0014] Preferably, adjusting the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization includes the following:

[0015] generating a frequency deviation modulation function by using the calculated angular frequency deviation;

[0016] The preset input signal expression is multiplied by the frequency deviation modulation function to correct the frequency deviation of the input signal and achieve signal synchronization.

[0017] Preferably, adjusting the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization includes the following:

[0018] generating a frequency deviation modulation function by using the calculated angular frequency deviation;

[0019] The expression of the preset input signal is multiplied by the frequency deviation modulation function and then by the phase deviation modulation function, and the frequency deviation and phase deviation of the input signal are corrected to achieve signal synchronization.

[0020] Preferably, the expression of the preset input signal is:

[0021]

[0022] in, is the expression of the i-channel signal of the receiver, is the expression of the receiver's q-path signal, is the expression of the transmitted baseband signal, is an imaginary unit, is the angular frequency deviation, is the initial phase difference between the transmitter carrier and the receiver carrier.

[0023] Preferably, the expression of the i-channel signal of the receiver is:

[0024]

[0025] The receiver The expression of the road signal is:

[0026]

[0027] in, represents the transmitter's carrier angular frequency, is the receiver’s carrier angular frequency, is the initial phase of the transmitter carrier, is the initial phase of the receiver carrier, represents the angular frequency deviation, Represents the initial phase difference between the transmitter carrier and the receiver carrier.

[0028] Preferably, calculating the phase angles of multiple PN sequences includes the following:

[0029] The PN sequence of the input signal is correlated with the local PN sequence to obtain the expression of m correlation peaks;

[0030] The expression of the latter correlation peak is divided by the expression of the former correlation peak to obtain the phase angles of the multiple PN sequences.

[0031] Preferably, the expression of the m correlation peaks is:

[0032]

[0033] in, The expression representing the first correlation peak, The expression representing the second correlation peak, The expression representing the mth correlation peak, the sampling sequence of PN is simplified to p(n), A>0 is the amplitude of PN, in which n=0, 1, 2, ..., N-1, where N=256; p(n)=+1 or -1.

[0034] A second aspect of the present application provides a signal synchronization device, including a receiver, and applies the above-mentioned signal synchronization method.

[0035] The beneficial effects of the present invention are at least one of the following:

[0036] By calculating and correcting the angular frequency deviation, the positioning accuracy of the ranging positioning system can be significantly improved. It can effectively compensate for the time delay error caused by the angular frequency deviation, help improve the demodulation quality of the signal, reduce the bit error rate, and thus improve the measurement accuracy of the system.

[0037] Even if the crystal oscillator stability of the high-precision clock is reduced and the frequency deviation becomes larger due to the temperature drift effect and aging effect, the present application can recalculate the angular frequency deviation and phase deviation as needed, and adjust the frequency and phase of the input signal accordingly, which can deal with the problem of crystal oscillator stability changes caused by factors such as temperature drift and aging effect during the long-term operation of the crystal oscillator. The long-term stability and reliability of signal synchronization are ensured.

[0038] By calculating the phase angles of multiple PN sequences separately and selecting the accumulation or averaging method to estimate the angular frequency deviation according to different situations (angular frequency deviation size), the robustness of the system is enhanced. This method can adapt to angular frequency deviations of different sizes and improve the adaptability and flexibility of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a method flow chart of Example 1 of the present application. DETAILED DESCRIPTION

[0040] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0041] Embodiment 1

[0042] The signal synchronization method in this embodiment can be applied in a ranging and positioning system. The ranging and positioning system includes at least a transmitter and a receiver. Before applying the signal synchronization method in this embodiment, an expression of the input signal with frequency deviation and phase deviation can be pre-modeled.

[0043] Assume that the expression of the transmitted baseband signal is , The synchronous PN sequence is a sequence whose amplitude A is +1 or -1.

[0044] PN=A×[1-1-1-1111-111-1-1-111111-1-111-1-11-1-1-1-1], a total of 32 bits, each bit has undergone 8 times of sampling interpolation, that is, the PN sequence has undergone 32*8=256 sampling points, the sampling time interval is 10 nanoseconds, or the sampling frequency is 100MHz, let the sampled PN sequence be represented by p(n). For the chirp sequence, each chirp has a total of 80 sampling points, and the expression of the chirp sequence is:

[0045]

[0046] B represents the bandwidth of the chirp. In this embodiment, the value of B is 23 MHz. represents the duration of the chirp code. In this embodiment, microseconds, k represents the number of Hz that the frequency rises per second, and A represents the signal amplitude.

[0047] In this embodiment, the transmitter is a single-channel transmitter, that is, only the signal of channel i is multiplied by , without adding the q-path signal multiplied by , or , so the RF signal expression emitted by the transmitter is:

[0048]

[0049] in, represents the transmitter's carrier angular frequency, is the initial phase of the transmitter carrier.

[0050] The carrier angular frequency used by the receiver is , Usually not equal to , the initial phase of the receiver is , nor is it usually equal to At this time, the receiver uses Multiply by formula (2), and use Multiply by formula (2), and then perform low-pass filtering respectively, then the expression of the i-channel signal of the receiver is obtained as follows:

[0051]

[0052] The expression of the q-path signal of the receiver is:

[0053]

[0054] in, represents the transmitter's carrier angular frequency, is the receiver’s carrier angular frequency, is the initial phase of the transmitter carrier, is the initial phase of the receiver carrier, represents the angular frequency deviation, Represents the initial phase difference between the transmitter carrier and the receiver carrier.

[0055] Will Combined together, they form the expression for the receiver input signal:

[0056]

[0057] in, is the expression of the i-channel signal of the receiver, is the expression of the receiver's q-path signal, is the expression of the transmitted baseband signal, j is the imaginary unit, is the angular frequency deviation, is the initial phase difference between the transmitter carrier and the receiver carrier.

[0058] It can be seen from formulas (3), (4), and (5) that when there is frequency deviation, , the i-channel signal and q-channel signal of the receiver are respectively and Modulation, when When is larger, the angular frequency of modulation is larger, and the i part and the q part rise and fall one after another, that is, the i part and the q part cannot become very small at the same time, nor can they become very large at the same time.

[0059] When frequency deviation correction is required, both the i-channel signal and the q-channel signal need to be retained. If the angular frequency deviation can be calculated, , we can construct a complex exponential function , which is used to multiply the received signal, In fact, a complex plane is generated with is the counterclockwise rotation vector of the rotation rate, which effectively cancels out the rotation vector The phase linear change caused by this process restores the signal to a state without frequency deviation. This process is called frequency deviation correction.

[0060] After the frequency correction is completed, the received signal still has a fixed phase deviation , construct a complex exponential function . It is essentially a complex number with a fixed phase, which is used to rotate the signal radians, thus completely canceling out the original phase deviation. This process is called phase correction.

[0061] In summary, we only need to multiply the received signal by The frequency deviation and phase deviation can be corrected to achieve signal synchronization.

[0062] A signal synchronization method is applied to a synchronization device, such as Figure 1 As shown, the following steps are included:

[0063] Step 1: Receive input signal.

[0064] Since the input signal may be affected by various factors during the transmission process, such as temperature, humidity, electromagnetic interference, etc., which may cause the frequency of the input signal to change, the input signal usually has a frequency deviation. Therefore, in a possible implementation, after the receiver receives the input signal, it directly executes the subsequent step 2 to start correcting the frequency deviation.

[0065] In another possible implementation, considering that the frequency deviation of the input signal is related to the stability of the crystal oscillator, for example:

[0066] Assume that the desired carrier frequencies of both the transmitter and receiver are =2.4GHz, the stability of the crystal used is to When the stability is expressed as the deviation between the actual frequency output of the crystal and the expected frequency divided by the expected frequency. -6 is more stable, while 10-5 Poor. =2.4GHz,w=10 -6 When , we can get from formula (5):

[0067]

[0068] This shows that the effect of frequency deviation is equivalent to the baseband signals of channels i and q being modulated by a 2.4KHz sinusoidal signal, the period of which is , while the baseband signal The duration of the chirp code is .

[0069] The chirp period accounts for the sine period At this point, it can be considered that the chirp code has a constant amplitude during the period of time it lasts. ,exist It is almost constant in any interval of , and this change can be completely ignored.

[0070] When considering whether the PN sequence is affected by frequency offset, the duration of a single PN sequence is .

[0071] PN duration The ratio is , is still relatively small, and the amplitude change caused by the frequency deviation can still be ignored.

[0072] when At this time , which is equivalent to the baseband signals of path i and path q being modulated by a 24KHz sinusoidal signal. becomes 41.7 microseconds. Obviously, the chirp cycle takes up The share becomes 0.019, and the amplitude change of the chirp in this time period can still be ignored. Considering the period of the PN sequence, it is found that The ratio becomes 0.061, and the change in amplitude can be ignored.

[0073] Further assume that the carrier frequency deviation is more severe, that is, When the chirp cycle is The ratio will become 0.19, and the duration of the PN sequence accounts for The share of chirp and PN will become 0.61. At this time, it can no longer be considered that the amplitude of chirp and PN is constant during their duration. Generally speaking, it can be considered that when the period of chirp and PN accounts for When the share is equal to or less than 0.1, the amplitude change can be ignored, but when it is greater than 0.1, the amplitude change needs to be considered. The share needs to be determined by measurement.

[0074] Although the stability of the crystal oscillator is to When the frequency deviation changes slightly, the amplitude of the frequency deviation changes little, but the stability of the crystal oscillator will be affected by the temperature drift effect and the aging effect. The stability of the crystal oscillator will gradually decrease, resulting in a gradual increase in the frequency deviation and phase deviation. In addition, during the long-term use of the crystal oscillator, due to mechanical vibration or shock, it may cause slight changes in its internal structure, thus affecting the stability of the crystal oscillator. In addition to physical changes, the electrical parameters of the crystal oscillator will also change over time, and these changes will also affect the stability of the crystal oscillator.

[0075] Therefore, relying solely on a high-precision clock cannot completely correct the frequency deviation and phase deviation that appear in the signal. In a possible implementation, the input signal includes a PN sequence and a chirp sequence. After receiving the input signal, the proportion of the PN sequence and the chirp sequence in the signal period can be calculated first; if the proportion of the PN sequence and the chirp sequence in the signal period is greater than a preset proportion threshold, step 2 is executed; if the proportion of the PN sequence and the chirp sequence in the signal period is less than or equal to the preset proportion threshold, the input signal is not corrected for frequency deviation.

[0076] By calculating the proportion of PN sequence and chirp sequence in the signal period, the frequency deviation information in the signal can be captured more comprehensively, thereby improving the accuracy of frequency deviation detection. Even if the frequency stability of the crystal oscillator decreases due to aging and temperature drift effects, this implementation can dynamically determine whether there is an obvious frequency deviation problem in the signal, and dynamically adjust the frequency deviation correction strategy to ensure timely response when the frequency deviation amplitude changes in the signal.

[0077] It should be noted that by calculating the proportion of PN sequence and chirp sequence in the signal period, it can be determined whether frequency deviation correction is needed. This allows the system to decide whether to start the frequency deviation correction procedure based on the actual situation of the signal, thereby improving the robustness and flexibility of the system. When the proportion of PN sequence and chirp sequence is lower than the preset threshold, the system can choose not to perform frequency deviation correction on the input signal. This can save computing resources and processing time, especially when the frequency deviation of the signal itself is less affected, avoiding unnecessary processing and improving resource utilization efficiency.

[0078] Step 2, perform preliminary angular frequency deviation estimation on the input signal and calculate phase angles of multiple PN sequences respectively;

[0079] For reference, a preliminary frequency deviation estimate is made for the input signal, and the approximate range of the frequency deviation can be determined by FFT (Fast Fourier Transform) or other spectrum analysis methods.

[0080] The calculation of the phase angles of multiple PN sequences includes the following:

[0081] The PN sequence of the input signal is correlated with the local PN sequence to obtain expressions of m correlation peaks; the expression of the latter correlation peak is divided by the expression of the former correlation peak to obtain the phase angles of multiple PN sequences.

[0082] By calculating the phase angles of multiple PN sequences, the phase deviation of the input signal can be estimated more accurately. The calculation of the phase angle is based on the phase difference between the correlation peaks, which can more accurately reflect the true phase information of the signal.

[0083] The calculation of multiple correlation peaks can enhance the anti-interference ability of the system. Even in the presence of noise or other interference, the phase angle calculation of multiple correlation peaks can better filter out interference and improve the reliability of phase estimation.

[0084] Through multiple correlation operations and phase angle calculations, the robustness of the system can be improved. Even if a single correlation peak is affected by interference or error, relatively accurate phase information can still be obtained through comprehensive consideration of multiple correlation peaks.

[0085] Specifically, capture the first PN sequence and let ,in represents the sampling time interval. In this embodiment, Take 10 nanoseconds, so the input signal received by the receiver can be expressed as:

[0086]

[0087] Among them, the sampling sequence of PN is simplified to p(n), A>0 is the amplitude of PN, in the above formula n=0, 1, 2, ..., N-1, where N=256; p(n)=+1 or -1.

[0088] When the receiver's PN sequence is correlated with the local PN, the expression for the first correlation peak is:

[0089]

[0090] Similarly, the expression for the second correlation peak can be obtained as:

[0091]

[0092] Because the initial phase of the second PN sequence increases relative to the first PN sequence The initial phase of the m-th PN sequence can be calculated as follows:

[0093]

[0094] use Divide by get:

[0095]

[0096] In the above formula , , , and It can be obtained from the complex number constructed from the i-part and q-part of the correlation peak. Specifically, let the i-part of the m-th correlation peak be , q part is ,but , so we can calculate From the above formula, we can see that The modulus values ​​are all equal, which can be verified in the receiver. It can also be seen that the phase angle of the complex number obtained by dividing the second correlation peak with respect to the first correlation peak is N times, the phase angle of the third correlation peak relative to the second correlation peak is also N times, the phase angle of the fourth correlation peak relative to the third correlation peak is also The phase angle of the fourth correlation peak relative to the first correlation peak will be The phase angle of the fourth correlation peak relative to the first correlation peak is 3N times the phase angle difference of the first three PN sequences added together.

[0097] Step 3, when the angular frequency deviation of the input signal is less than or equal to the preset angular frequency deviation threshold, the phase angles of multiple PN sequences are accumulated to calculate the angular frequency deviation; when the angular frequency deviation of the input signal is greater than the preset angular frequency deviation threshold, the average value of the phase angles of multiple PN sequences is calculated to calculate the angular frequency deviation.

[0098] Calculating the phase angles of multiple PN sequences can improve the accuracy of frequency offset estimation. When the frequency offset is small, the frequency offset is calculated by accumulating the phase angles of multiple PN sequences; when the frequency offset is large, the frequency offset is calculated by calculating the average of the phase angles of multiple PN sequences. This method can obtain better results under different frequency offset conditions.

[0099] Different calculation methods can be flexibly selected under different frequency deviation conditions. When the frequency deviation is small, the phase angle is accumulated; when the frequency deviation is large, the average phase angle is calculated. This flexibility enables the system to adapt to different working environments and signal conditions.

[0100] Specifically, when the angular frequency deviation of the input signal is less than or equal to the preset angular frequency deviation threshold, the phase angles of the three PN sequences are accumulated together, that is, by The result of When the angular frequency deviation of the input signal is greater than the preset angular frequency deviation threshold, calculate , , Count three , we can get a more accurate .

[0101] Asked for Afterwards, due to , then the real part I and imaginary part Q of the complex number are known. If we assume If it is an acute angle, then both the real and imaginary parts of the complex number are greater than zero, I>0 and Q>0, so:

[0102]

[0103] Can be found .

[0104] In a possible implementation, the complex phase angle can be obtained by Verilog, and the sine and cosine calculations can be implemented by Verilog.

[0105] In another possible implementation, use C language to find , this can send an interrupt to the CPU through Verilog and transmit complex numbers to the CPU , and then use C language to find , using C language to do the following operations, we can get The specific process is to make ,but , seek its The second power is the requirement Once we find ,and is equal to its conjugate, Nature can also be found out.

[0106] Request ,because It is very close to 0, so we use the Taylor series expansion:

[0107]

[0108] in represent The first derivative at 0 is taken as represent The second-order derivative at 0 is represent The third-order derivative at 0 is represent The fourth-order derivative is taken at 0. Let , then according to formula (13), the following calculation process is obtained:

[0109]

[0110] Substitution have:

[0111]

[0112] This is a complex number. Simply taking the conjugate of this complex number will give . Desire One is to use Verilog to find it, and the other is to use C language to find it and put it into a 128*8 memory array for the IP core to call.

[0113] In this embodiment, the inverse operation of the complex exponential function is approximated by the Taylor series expansion, which can improve the accuracy of the calculation. The Taylor series expansion can be used to simplify This method avoids the complexity of direct inversion operations, making the calculation simpler and more efficient. Verilog is used for hardware implementation, which can calculate the complex phase angle in real time and notify the CPU for further processing through the interrupt mechanism. This method can greatly improve the real-time performance of signal processing and is suitable for occasions that require fast response. The hardware calculation implemented by Verilog reduces the calculation burden of the CPU. The software part implemented in C language can also be expanded or modified as needed, which improves the scalability of the system.

[0114] Step 4: adjust the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization.

[0115] Specifically, a frequency deviation modulation function is generated by the calculated angular frequency deviation;

[0116] The preset input signal expression is multiplied by the frequency deviation modulation function to correct the frequency deviation of the input signal and achieve signal synchronization.

[0117] In this embodiment, the frequency deviation modulation function is: . You can calculate Then use the preset input signal expression, that is, formula (5) multiplied by Then we can get s(t), complete the frequency deviation correction, and then multiply it by the phase deviation modulation function , complete the phase correction, thereby achieving signal synchronization.

[0118] In this embodiment, by calculating and correcting the angular frequency deviation, the positioning accuracy of the ranging and positioning system can be significantly improved. It can effectively compensate for the time delay error caused by the angular frequency deviation, help improve the demodulation quality of the signal, reduce the bit error rate, and thus improve the measurement accuracy of the system. Compared with the traditional method of using a high-precision clock to reduce the influence of the angular frequency deviation, the present invention uses a software algorithm to realize the estimation and correction of the angular frequency deviation, avoids the hardware complexity and cost increase brought by the introduction of a high-precision clock, reduces the dependence on hardware, and estimates the angular frequency deviation by calculating the phase angles of multiple PN sequences respectively, and selecting the accumulation or averaging method according to different situations (angular frequency deviation size), thereby enhancing the robustness of the system. It can adapt to angular frequency deviations of different sizes, improve the adaptability and flexibility of the system, and because a software algorithm is used instead of a hardware clock to solve the angular frequency deviation problem, the angular frequency deviation and phase deviation can be recalculated as needed, and the frequency and phase of the input signal can be adjusted accordingly, which can deal with the problem of crystal oscillator stability changes caused by factors such as temperature drift and aging effects during the long-term operation of the crystal oscillator. The long-term stability and reliability of signal synchronization are ensured. The present invention can not only generate a modulation function according to the angular frequency deviation to correct the frequency deviation, but also simultaneously generate a frequency deviation modulation function and a phase deviation modulation function to comprehensively correct the frequency deviation and phase deviation of the input signal, thereby further improving the accuracy of signal synchronization.

[0119] Embodiment 2

[0120] This embodiment provides a signal synchronization device, including a receiver, and applies the signal synchronization method described in the first embodiment.

[0121] It can be understood that the signal synchronization device in this embodiment also includes a transmitter, and the hardware performance of the transmitter is consistent with that of the receiver. For example, both the transmitter and the receiver use the same crystal oscillator (crystal oscillator) to generate their carrier frequencies, and the bandwidths of the transmitter and the receiver are also the same.

[0122] In summary, the signal synchronization device in this embodiment achieves efficient and reliable signal synchronization by ensuring the consistency of hardware performance between the transmitter and the receiver. Both the transmitter and the receiver use the same crystal oscillator to generate the carrier frequency, ensuring a high degree of frequency stability between the two; at the same time, the same bandwidth setting ensures the integrity and reliability of the signal during signal transmission and reception, thereby improving the performance of the entire system.

[0123] The above-mentioned embodiments only express the specific implementation of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A signal synchronization method, applied to a synchronization device, characterized in that: Includes the following: Receiving an input signal; wherein the input signal includes a PN sequence; Perform preliminary angular frequency deviation estimation on the input signal and calculate phase angles of multiple PN sequences respectively; When the angular frequency deviation of the input signal is less than or equal to the preset angular frequency deviation threshold, the phase angles of multiple PN sequences are accumulated to calculate the angular frequency deviation; when the angular frequency deviation of the input signal is greater than the preset angular frequency deviation threshold, the average value of the phase angles of multiple PN sequences is calculated to calculate the angular frequency deviation; Adjust the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization; Adjust the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization including the following: generating a frequency deviation modulation function by using the calculated angular frequency deviation; Multiplying the preset input signal expression by the frequency deviation modulation function to correct the frequency deviation of the input signal and achieve signal synchronization; Adjust the frequency of the input signal according to the calculated angular frequency deviation to achieve signal synchronization including the following: generating a frequency deviation modulation function by using the calculated angular frequency deviation; The expression of the preset input signal is multiplied by the frequency deviation modulation function and then by the phase deviation modulation function, and the frequency deviation and phase deviation of the input signal are corrected to achieve signal synchronization; The expression of the preset input signal is: ； in, is the expression of the i-channel signal of the receiver, is the expression of the receiver's q-path signal, is the expression of the transmitted baseband signal, is an imaginary unit, is the angular frequency deviation, is the initial phase difference between the transmitter carrier and the receiver carrier; The expression of the i-channel signal of the receiver is: ； The expression of the q-path signal of the receiver is: ； in, represents the transmitter's carrier angular frequency, is the receiver’s carrier angular frequency, is the initial phase of the transmitter carrier, is the initial phase of the receiver carrier, represents the angular frequency deviation, Represents the initial phase difference between the transmitter carrier and the receiver carrier; Calculating the phase angles of multiple PN sequences includes the following: The PN sequence of the input signal is correlated with the local PN sequence to obtain the expression of m correlation peaks; Divide the expression of the latter correlation peak by the expression of the former correlation peak to obtain the phase angles of multiple PN sequences; The expression of the m correlation peaks is: ； in, The expression representing the first correlation peak, The expression representing the second correlation peak, The expression representing the mth correlation peak, the sampling sequence of PN is simplified to p(n), A>0 is the amplitude of PN, in which n=0, 1, 2, ..., N-1, where N=256; p(n)=+1 or -1.

2. A signal synchronization method according to claim 1, characterized in that: The receiving of the input signal comprises the following contents: Receiving an input signal, wherein the input signal includes a PN sequence and a chirp sequence; Calculate the proportion of the PN sequence and the chirp sequence in the signal period; if the proportion of the PN sequence and the chirp sequence in the signal period is greater than the preset proportion threshold, execute the next step; if the proportion of the PN sequence and the chirp sequence in the signal period is less than or equal to the preset proportion threshold, do not correct the frequency deviation of the input signal.

3. A signal synchronization device, comprising a receiver, characterized in that: Apply the signal synchronization method described in any one of claims 1-2.

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