Non-cooperative measurement and control signal carrier recovery method and device based on pseudo code hopping edge detection

Abstract

The invention provides a non-cooperative measurement and control signal carrier recovery method and device based on pseudo code jump edge detection, and belongs to the technical field of radar signal processing, and the specific process is as follows: setting the stepping amount of a local timing synchronization pulse accumulator, and when the accumulated value of the timing synchronization pulse accumulator is greater than a set threshold value, stopping the stepping amount of the local timing synchronization pulse accumulator; the accumulator outputs a timing synchronization pulse signal; controlling a sliding accumulator by using a synchronization pulse signal to perform sliding accumulation on a constellation module value # imgabs2 # calculated by the # imgabs0 # baseband signal and the # imgabs1 # baseband signal, and further obtaining a synchronization pulse capture offset for coarse synchronization of a timing synchronization pulse; obtaining a correlation value of a # imgabs3 path baseband signal and a # imgabs4 path baseband signal under the control of a timing synchronization pulse after coarse synchronization, obtaining a timing error by using a timing error discriminator, and further obtaining a stepping amount of a synchronization pulse accumulator; and realizing carrier recovery by using the stepping amount of the synchronization pulse accumulator.

Description

Technical Field

[0001] The present invention provides a method and device for recovering a carrier wave of a non-cooperative measurement and control signal based on pseudo code transition edge detection, belonging to the technical field of radar signal processing. Background Art

[0002] Traditional signal synchronization extraction methods based on a delay-locked loop (DDLL) combined with a frequency-locked loop (FLL) and a phase-locked loop (PLL) require the code table information of the known transmitted signal to strip off the modulation pseudocode before effectively recovering the carrier. In non-cooperative mode, the phase jump introduced by the modulation pseudocode causes the carrier recovery performance to be severely degraded or even fail.

[0003] To address the carrier recovery problem in non-cooperative measurement and control signals, in 2017, Chongqing University graduate student Chen Zhiliang proposed a carrier recovery method using FFT carrier estimation and Costas loops in his master's thesis, "Research and Implementation of Carrier Recovery Technology for Non-Cooperative Communications." This method first eliminates the influence of the modulation pseudo-code by performing a power operation, then uses FFT calculations to obtain a rough estimate of the carrier frequency. Finally, the Costas loop is used to accurately track the carrier frequency and phase.

[0004] Patent CN113904901A proposes a carrier recovery method for various bandwidths and modulation schemes. This method combines oversampling, multi-rate DDC, and Costas loop techniques to effectively overcome the effects of pseudo-code transitions and achieve carrier recovery for non-cooperative measurement and control signals.

[0005] The carrier recovery method based on FFT carrier estimation assisted Costas loop proposed in "Research and Implementation of Non-cooperative Communication Carrier Recovery Technology" is only applicable to MPSK modulated signals. The power operation introduces noise cross-terms. The higher the modulation order, the more cross-terms are introduced, resulting in a serious degradation or even failure of the carrier recovery performance when the thermal noise of the receiver is greatly affected.

[0006] Patent CN113904901A proposes a carrier recovery method for multiple bandwidths and modulation modes. This method adjusts the sampling rate to 12 times or 16 times the signal bandwidth, and synchronously recovers the oversampled signal through a Costas phase-locked loop carrier. Although this method can effectively overcome the impact of phase jumps caused by pseudo-code modulation information, it cannot effectively utilize the energy accumulation within the same symbol of the pseudo-code modulation signal. The carrier recovery accuracy is poor in a low signal-to-noise ratio environment. In addition, this method uses a phase-locked loop to synchronously recover the carrier. When the frequency difference of the received signal is large, the phase-locked loop converges slowly, and the processing time required for carrier recovery increases. Summary of the Invention

[0007] In view of this, the present invention proposes a non-cooperative measurement and control signal carrier recovery method and device based on pseudo code jump point detection, which improves the accuracy of non-cooperative measurement and control signal carrier recovery under low signal-to-noise ratio and improves the speed of non-cooperative measurement and control signal carrier recovery under large frequency difference.

[0008] The technical solutions for implementing the present invention are as follows: In a first aspect, the present invention provides a non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance, the specific steps of which are as follows: Step 1: Perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Luhe Roadbed with signal; Step 2: Set the step size of the local timing synchronization pulse accumulator. When the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold, the timing synchronization pulse signal is output. The timing synchronization pulse signal is used to control the sliding accumulator to Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse signal; Step 3: Obtain under the control of the timing synchronization pulse signal after coarse synchronization Luhe A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; Step 4: Utilize the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

[0009] Optionally, in step 2 of the present invention, the step size of the local timing synchronization pulse accumulator is set to , , is the code rate, is the sampling interval; when the accumulated value of the timing synchronization pulse accumulator is greater than 1, the timing synchronization pulse signal is output.

[0010] Optionally, the present invention uses a timing synchronization pulse signal to control the sliding accumulator Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the synchronization pulse capture offset for coarse synchronization of the timing synchronization pulse signal. The specific process is as follows: First, when the sliding accumulator receives the timing synchronization pulse signal, Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation to obtain the sliding accumulation values within a single code element ; Secondly, the sliding accumulation value within a single code element Perform non-coherent accumulation and add the sliding accumulated value after non-coherent accumulation Select the largest value and record the number of sliding sampling points corresponding to the maximum value. , the sampling points As the capture offset of the timing synchronization pulse; Finally, the capture offset is synchronized with the step size of the timing synchronization pulse accumulator. After multiplication, the signals are accumulated into the timing synchronization pulse accumulator to complete the coarse synchronization of the timing error.

[0011] Optionally, the step 3 of the present invention is to obtain the timing synchronization pulse after the coarse synchronization under the control of Luhe The relevant value of the roadbed signal is as follows: After low-pass filtering Luhe The roadbed signal is controlled by the timing synchronization pulse signal after coarse synchronization to obtain the instantaneous correlation value of the code element jump moment. and , and the correlation values of the two paths ahead and behind the symbol jump time 、 and 、 .

[0012] Optionally, the timing error discriminator of the present invention adopts the Gardner algorithm to calculate the timing error based on the correlation value , and use a low-pass filter to filter out the timing error Update the step size of the timing synchronization pulse accumulator after out-of-band noise .

[0013] Optionally, the step size of the present invention for:

[0014] in, is the filter gain, is the damping coefficient, is the natural angular frequency, is the sampling interval.

[0015] Optionally, the specific process of step 4 of the present invention is: filtering and smoothing the step amount of the timing synchronization pulse accumulator, and calculating the carrier frequency difference based on the relationship between the code rate residual and the carrier frequency residual, and using the carrier frequency difference to update the local carrier; under the control of the timing synchronization pulse accumulator, using the updated local carrier's down-conversion signal to perform accumulation with a duration of 1 code bit and calculate the carrier phase error, and bringing the carrier phase error into the loop filter to restore the local carrier frequency.

[0016] Optionally, the present invention calculates the carrier frequency difference based on the relationship between the code rate residual and the carrier frequency residual as:

[0017] in, is the code rate, For local carrier, The carrier frequency residual obtained by filtering and smoothing.

[0018] Optionally, when calculating the carrier phase error, the present invention uses different phase detectors to calculate the carrier phase error according to different signal modulation modes.

[0019] In a second aspect, the present invention provides a non-cooperative measurement and control signal carrier recovery device based on pseudo-code transition point blind detection assistance, comprising: The non-cooperative measurement and control signal processing module is used to perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Luhe Roadbed with signal; The pseudo code jump edge blind search module is used to set the step size of the local timing synchronization pulse accumulator. When the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold, the timing synchronization pulse signal is output; the timing synchronization pulse signal is used to control the sliding accumulator to Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse; Timing error compensation module, used to obtain the timing synchronization pulse signal after coarse synchronization Luhe A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; The carrier recovery module uses the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

[0020] Beneficial effects First, the present invention determines the code element duration by blindly searching the pseudo code transition edge of the non-cooperative measurement and control signal, and performs accumulation within the code element duration to achieve effective accumulation of energy within the code element.

[0021] Second, the present invention obtains the code frequency difference from the timing synchronization loop filtering result, calculates the carrier frequency difference according to the relationship between the code frequency difference and the carrier frequency difference, and compensates for it, effectively reducing the impact of the large frequency difference during carrier recovery.

[0022] Third, the present invention performs Luhe The orthogonal down-conversion value of the roadbed signal is correlated with a duration of one chip to obtain the signal-to-noise ratio gain, thereby improving the synchronization performance of the algorithm in a low signal-to-noise ratio environment.

[0023] Fourth, the present invention selects different phase discrimination algorithms for different modulation modes and designs the tracking loop as a composite loop in which multiple phase discrimination algorithms are used in parallel, so that the present invention is compatible with multiple direct sequence spread spectrum modulation modes. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a schematic diagram of the pseudo-code sliding accumulator principle.

[0026] Figure 2 This is a schematic diagram of the multi-loop carrier synchronization process.

[0027] Figure 3 This is the phase tracking error comparison result between this QPSK modulation method and the method in patent CN113904901A.

[0028] Figure 4 This is the phase tracking error comparison result between this method and the method in patent CN113904901A for 8PSK modulation.

[0029] Figure 5 The phase tracking error comparison results of this method and the patent CN113904901A method for 16QAM modulation are shown.

[0030] Figure 6 The comparison results of the phase-locked loop locking time between this QPSK modulation method and the method in patent CN113904901A are shown.

[0031] Figure 7The comparison results of the phase-locked loop locking time of this method and the patent CN113904901A method for 8PSK modulation are shown in Figure 2.

[0032] Figure 8 The comparison results of the phase-locked loop locking time between this method and the method in patent CN113904901A for 16QAM modulation are shown. DETAILED DESCRIPTION

[0033] The embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0034] It should be noted that, in the absence of conflict, the following embodiments and features in the embodiments may be combined with each other; and, based on the embodiments in this disclosure, all other embodiments obtained by persons of ordinary skill in the art without creative work are within the scope of protection of this disclosure.

[0035] It should be noted that various aspects of the embodiments within the scope of the appended claims are described below. It should be apparent that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is merely illustrative. Based on this disclosure, it should be understood by those skilled in the art that an aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number of aspects described herein can be used to implement an apparatus and / or practice a method. In addition, other structures and / or functionalities other than one or more of the aspects described herein can be used to implement this apparatus and / or practice this method.

[0036] The present application embodiment proposes a non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance, the specific process is as follows: Step 1: Perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Luhe Roadbed with signal; Step 2: Set the step size of the local timing synchronization pulse accumulator. When the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold, the timing synchronization pulse signal is output. The timing synchronization pulse signal is used to control the sliding accumulator to Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse signal; Step 3: Obtain under the control of the timing synchronization pulse signal after coarse synchronization Luhe A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; Step 4: Utilize the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

[0037] The following is a detailed description of the specific implementation process of each step: Step 1: Receive non-cooperative measurement and control signals and perform orthogonal down-conversion Assume that the received non-cooperative measurement and control signal is expressed as: (1) in, 、 is the modulation pseudo code, is the carrier frequency of the received signal, is the sampling interval, is the carrier phase.

[0038] Assume that the expression of the locally generated orthogonal down-converted signal is: (2) (3) Where, For the local carrier.

[0039] The received signal is orthogonally down-converted by equations (2) and (3), and the low-pass filtered signal is Luhe The roadbed signal expression is: (4) (5) in, Indicates the frequency difference between the received carrier and the local carrier. 、 is the pseudo code after filtering.

[0040] Step 2: Blind search of pseudo code transition edge The module value of the constellation diagram is obtained by summing the squares of equations (4) and (5). : (6) Initial value of local timing synchronization pulse accumulator Set to 0, the accumulator step size is initially set to:

[0041] in, is the code rate. If the timing synchronization pulse accumulator value is If it is greater than 1, the accumulator overflows, and it is determined that this is the pseudo code jump moment. The accumulator is operated on and a timing synchronization pulse signal is output.

[0042] When the timing synchronization pulse signal arrives, the sliding accumulator starts to perform the accumulation operation within the current code element, such as Figure 1 As shown, the result of formula (6) after sliding accumulator is expressed as: (7) in, is the current symbol number, is the number of sliding sampling points, is the number of sampling points contained in one chip.

[0043] The sliding accumulated values within the obtained single code element are Non-coherent accumulation is performed between code elements. The expression of non-coherent accumulation between code elements is: (8) Select the largest sliding cumulative value after non-coherent accumulation and record the number of sliding sampling points corresponding to the maximum value , which can be used as the capture offset of the timing synchronization pulse.

[0044] During the sliding accumulation process, if a pseudo-code edge occurs within the accumulation interval, the accumulation gain is lost. The closer the pseudo-code edge is to the midpoint of the accumulation interval, the greater the gain loss. Therefore, there is no pseudo-code edge within the sliding integration interval that produces the maximum result. Based on this characteristic, the estimated position of the pseudo-code edge can be inferred by the number of sliding sampling points.

[0045] (9) Capturing offsets Synchronous pulse accumulator step size with timing After multiplication, the signals are accumulated into the timing synchronization pulse accumulator to complete the coarse synchronization of the timing error.

[0046] (10) Step 3: Timing Error Compensation After low-pass filtering Road and Under the control of the timing synchronization pulse after the coarse synchronization, the subgrade signal obtains the instantaneous correlation value at the symbol jump moment. and , and the correlation values of the two paths ahead and behind the symbol jump time 、 and 、 , and with 、 They are then sent to the subsequent timing error discriminator.

[0047] The timing error discriminator uses the Gardner algorithm, and the formula is: (11) Get timing error After that, it is sent to the low-pass filter to filter out the out-of-band noise and then update the timing synchronization pulse accumulator step amount. , to complete the dynamic compensation of timing error. Step amount , that is, the time domain expression of the low-pass filter is: (12) Where, is the filter gain, is the damping coefficient, is the natural angular frequency, .

[0048] Step 4: Carrier Recovery The timing synchronization pulse accumulator step amount conduct Filter smoothing, the smoothing formula is as follows: (13) According to the relationship between the code rate residual and the carrier frequency residual, the carrier frequency residual can be obtained Inversely deduce the carrier frequency difference , as a rough estimate of the carrier frequency residual, that is (14) First, the local carrier is reconstructed using the carrier frequency difference estimation result given by equation (14) and down-converted. The updated local carrier expression is: (15) (16) Then, under the control of the timing synchronization pulse, the down-converted signal of the updated local carrier is accumulated for a duration of 1 chip. The accumulated signal is expressed as: (17) (18) in, is the residual carrier angular frequency error; To accumulate points; is the phase error.

[0049] like Figure 2As shown in the figure, in order to adapt to the carrier synchronization requirements of different signal modulation modes, a loop architecture with multiple phase detectors working in parallel is adopted. The loop synchronization result with the smallest steady-state error after locking is selected as the final synchronization output to complete the carrier synchronization of the corresponding modulation mode signal.

[0050] If the signal modulation method is BPSK, the phase detection formula is: (19) If the signal modulation method is QPSK or 16QAM, the phase detection formula is: (20) If the signal modulation method is 8PSK, the phase detection formula is: (twenty one) Get the carrier phase error After that, it is brought into the loop filter, low-pass filtered to remove out-of-band noise and update (i.e., restore) the local carrier frequency, so that the local carrier is completely synchronized with the carrier frequency and phase of the received measurement and control signal, completing the construction of the negative feedback loop.

[0051] The time domain expression of the low-pass filter is: (twenty two) Where, is the filter gain, is the damping coefficient, is the natural angular frequency, .

[0052] The present invention first accurately synchronizes the pseudo-code jump point, and then infers the carrier Doppler based on the obtained code Doppler and provides it to the carrier recovery stage. This process significantly reduces the initial frequency difference of carrier synchronization, thereby greatly improving the dynamic adaptability of the system.

[0053] In the carrier recovery (i.e. carrier synchronization) phase, the present invention Luhe The orthogonal down-converted signal of the subgrade band is subjected to a one-chip correlation integration process. Under the constraint that pseudo-code stripping is impossible, this method can obtain the longest possible correlation integration interval free of phase shifts. In this way, the present invention significantly improves synchronization performance in low signal-to-noise ratio environments, effectively enhancing the system's anti-interference capability and dynamic adaptability.

[0054] The embodiment of the present application provides a non-cooperative measurement and control signal carrier recovery device based on pseudo-code transition point blind detection assistance, including: The non-cooperative measurement and control signal processing module is used to perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Luhe Roadbed with signal; The pseudo code jump edge blind search module is used to set the step size of the local timing synchronization pulse accumulator. When the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold, the timing synchronization pulse signal is output; the timing synchronization pulse signal is used to control the sliding accumulator to Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse; Timing error compensation module, used to obtain the timing synchronization pulse signal after coarse synchronization Luhe A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; The carrier recovery module uses the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

[0055] In order to verify the effectiveness of the present invention, the following simulation experiments are carried out: The sampling frequency is 125MHz, and the corresponding sampling interval is 8ns, code rate In the sliding accumulation stage, the parameter In the inter-symbol non-coherent accumulation phase, considering the calculation delay and the non-coherent accumulation effect, the non-coherent accumulation of 16 chips is selected, and the parameter Select 16. In the low-pass filtering stage after timing error identification, select the total filter gain , damping coefficient , natural frequency . At the smoothing filter, select the parameters , perform smoothing filtering with an equivalent time length of about 6ms. The parameters selected for the carrier phase error loop filter are: total filter gain , natural frequency .

[0056] First, the synchronization error is simulated and compared. Under the input conditions of QPSK, 8PSK and 16QAM modulation signals, the simulation is carried out in the signal-to-noise ratio range of 10-20dB, 17-27dB and 14-24dB respectively. The carrier 3 after synchronization is taken as the Phase error is plotted as Figures 3 to 5 shown.

[0057] Subsequently, the synchronization speed was simulated and compared. Under the output conditions of QPSK, 8PSK and 16QAM modulation signals, the simulation was carried out in the initial frequency difference range of 5kHz-70kHz, 5kHz-40kHz, and 5kHz-55kHz respectively. The time taken from the start of synchronization to the completion of synchronization was plotted as shown in the figure. Figures 6 to 8 shown.

[0058] from Figures 3 to 5 It can be seen that when processing QPSK, 8PSK, and 16QAM signals, the steady-state error of this method is significantly reduced compared to existing methods under various signal-to-noise ratio environments. This shows that this method has significantly improved its noise resistance performance compared to existing methods.

[0059] from Figures 6 to 8 As can be seen, this method significantly reduces the initial carrier frequency offset by using a timing synchronization algorithm to compensate for the carrier frequency offset. This improvement significantly improves the locking time and frequency pulling range of this method compared to existing methods.

[0060] The present invention is applicable to a non-cooperative receiving system and can complete accurate synchronization of the carrier phase without obtaining a pseudo code table used by the transmitter for modulation in advance.

[0061] In summary, the above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance, characterized in that: The specific steps are as follows: Step 1: Perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Lu He Roadbed with signal; Step 2: Set the step size of the local timing synchronization pulse accumulator. When the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold, the timing synchronization pulse signal is output. The sliding accumulator is controlled by the timing synchronization pulse signal Lu He Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse signal; Step 3: Obtain under the control of the timing synchronization pulse signal after coarse synchronization Lu He A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; Step 4: Utilize the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

2. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 1 is characterized in that: In step 2, set the step size of the local timing synchronization pulse accumulator to , , is the code rate, is the sampling interval; when the accumulated value of the timing synchronization pulse accumulator is greater than 1, the timing synchronization pulse signal is output.

3. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 2 is characterized in that: The timing synchronization pulse signal is used to control the sliding accumulator Lu He Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the synchronization pulse capture offset for coarse synchronization of the timing synchronization pulse signal. The specific process is as follows: First, when the sliding accumulator receives the timing synchronization pulse signal, Lu He Constellation modulus value for roadbed signal calculation Perform sliding accumulation to obtain the sliding accumulation values within a single code element ; Secondly, the sliding accumulation value within a single code element Perform non-coherent accumulation and add the sliding accumulated value after non-coherent accumulation Select the largest value and record the number of sliding sampling points corresponding to the maximum value. , the number of sampling points As the capture offset of the timing synchronization pulse; Finally, the capture offset is synchronized with the step size of the timing synchronization pulse accumulator. After multiplication, the signals are added to the timing synchronization pulse accumulator to complete the coarse synchronization of the timing synchronization pulse signal.

4. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 3 is characterized in that: The timing synchronization pulse after the coarse synchronization is controlled to obtain Luhe The relevant value of the roadbed signal is as follows: After low-pass filtering Luhe The roadbed signal is controlled by the timing synchronization pulse signal after coarse synchronization to obtain the instantaneous correlation value of the code element jump moment. and , and the correlation values of the two paths ahead and behind the symbol jump time 、 and 、 .

5. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 4 is characterized in that: The timing error discriminator uses the Gardner algorithm to calculate the timing error based on the correlation value. , and use a low-pass filter to filter out the timing error Update the step size of the timing synchronization pulse accumulator after out-of-band noise .

6. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 5, characterized in that: The step size for: in, is the filter gain, is the damping coefficient, is the natural angular frequency, is the sampling interval.

7. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 1, characterized in that: The specific process of step 4 is as follows: The step amount of the timing synchronization pulse accumulator is filtered and smoothed, and the carrier frequency difference is calculated based on the relationship between the code rate residual and the carrier frequency residual, and the local carrier is updated using the carrier frequency difference. Under the control of the timing synchronization pulse accumulator, the down-converted signal of the updated local carrier is accumulated for a duration of 1 code chip and the carrier phase error is calculated. The carrier phase error is brought into the loop filter to recover the local carrier frequency.

8. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 7, characterized in that: According to the relationship between the code rate residual and the carrier frequency residual, the carrier frequency difference is calculated as: in, is the code rate, For local carrier, The carrier frequency residual obtained by filtering and smoothing.

9. The non-cooperative measurement and control signal carrier recovery method based on pseudo-code transition point blind detection assistance according to claim 7, characterized in that: When calculating the carrier phase error, different phase detectors are used for calculating the carrier phase error according to different signal modulation modes.

10. A non-cooperative measurement and control signal carrier recovery device based on pseudo-code transition point blind detection assistance, characterized in that: include: The non-cooperative measurement and control signal processing module is used to perform orthogonal down-conversion and low-pass filtering on the received non-cooperative measurement and control signal to obtain Lu He Roadbed with signal; The pseudo-code jump edge blind search module is used to set the step amount of the local timing synchronization pulse accumulator, and output the timing synchronization pulse signal when the accumulated value of the timing synchronization pulse accumulator is greater than the set threshold; The sliding accumulator is controlled by the timing synchronization pulse signal Luhe Constellation modulus value for roadbed signal calculation Perform sliding accumulation and further obtain the capture offset of the timing synchronization pulse for coarse synchronization of the timing synchronization pulse; Timing error compensation module, used to obtain the timing synchronization pulse signal after coarse synchronization Luhe A correlation value of the roadbed band signal, and a timing error obtained based on the correlation value and using a timing error discriminator, for updating a step amount of a timing synchronization pulse accumulator; The carrier recovery module uses the step amount of the timing synchronization pulse accumulator to realize carrier recovery.

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