A pulse compression amplitude ratio distance measurement method

Abstract

The present invention discloses a pulse compression amplitude ratio ranging method, comprising the following steps: step 1, generating a linear frequency modulation signal and its echo signal without noise interference, sampling the echo signal, and obtaining a digital signal; step 2, performing pulse compression processing on the digital signal to obtain a first digital signal; step 3, selecting a windowing function to perform windowing processing on the first digital signal, reducing the signal side lobe, and obtaining a second digital signal; step 4, generating a distance scale value-amplitude ratio table according to the second digital signal; step 5, calculating the actual target distance value. The present invention generates a distance scale value-amplitude ratio table by sampling the amplitude ratio within the distance unit of the noise-free linear frequency modulation signal, and obtains the target position by looking up the table when obtaining the echo of the linear frequency modulation signal containing noise, thereby improving the radar target ranging accuracy and the speed of the algorithm.

Description

Technical Field

[0001] The invention relates to the field of radar target detection, and in particular to a pulse compression amplitude ratio ranging method. Background Art

[0002] In recent years, with the development of integrated components and digital signal processing technology, Linear Frequency Modulation Continuous Wave (LFMCW) radar technology has also been greatly developed, and its application range has become more and more extensive. Compared with other radar systems, LFMCW radar has the advantages of no range blind spot, high range resolution, large signal energy, simple structure, and low operating voltage. It is particularly suitable for various speed and distance measurement systems in the military field, such as: missile guidance, ship navigation, battlefield reconnaissance, etc. Therefore, the requirements for the accuracy of distance measurement are getting higher and higher, and the importance of its research is also increasing.

[0003] Existing radar ranging technologies mostly use amplitude linear weighting methods to estimate target positions. For example, the article "An Improved Ranging Algorithm in Radar Ranging System" (Electronic Design Engineering, Vol. 21, No. 1, 2013) discloses an amplitude weighted fitting method based on distance spectrum. This method only fits the maximum and second-largest values ​​of importance in the distance spectrum. It is a local fitting method, rather than fitting the entire curve, so it can greatly reduce the budget and improve efficiency. Compared with the amplitude maximum value binary estimation method, this method has a certain degree of improvement in ranging accuracy. However, there are still some shortcomings: the distance fitting accuracy of this method is limited by the sampling frequency, so the accuracy is limited. Compared with the maximum value binary estimation method compared with itself, the accuracy is only slightly improved, which cannot meet the actual task requirements. Summary of the invention

[0004] In order to solve the above problems, the present invention proposes a pulse compression amplitude ratio ranging method, comprising the following steps:

[0005] Step 1: Generate a linear frequency modulation signal and its echo signal without noise interference, sample the echo signal, and obtain a digital signal;

[0006] Step 2: performing pulse compression processing on the digital signal to obtain a first digital signal;

[0007] Step 3, selecting a windowing function to perform windowing processing on the first digital signal to reduce the signal side lobe to obtain a second digital signal;

[0008] Step 4: generating a distance scale value-amplitude ratio table according to the second digital signal; the distance scale value-amplitude ratio table includes a plurality of distance scale values ​​and amplitude ratios corresponding thereto one by one;

[0009] The specific method for obtaining the distance scale value is to select points within two sampling distance units centered on the reference target point of the second digital signal with a step length of M, and the value of any point is the distance scale value;

[0010] The specific method for obtaining the amplitude ratio is to obtain the corresponding scale target point position according to the distance scale value and the reference target point, repeat steps 1-3, and calculate the ratio of the absolute values ​​of the amplitude values ​​of the points of two adjacent sampling numbers on the second digital signal, and the ratio of the amplitude values ​​is the amplitude ratio;

[0011] Step 5: Calculate the actual target distance value:

[0012] Add random Gaussian white noise to the digital signal in step 1; repeat steps 1-3 to obtain a third digital signal;

[0013] For the third digital signal, arbitrarily select points at two adjacent sampling numbers, calculate the ratio of the absolute values ​​of their amplitude values, look up the distance scale value-amplitude ratio table to obtain the corresponding distance scale value, and thus obtain the actual target distance value.

[0014] Further, Among them, r_unit is the sampling distance unit, V c is the speed of light, F s is the sampling frequency F when obtaining the digital signal from the echo signal s , is the distance scale value corresponding to the point with the first sampling number, It is the distance scale value corresponding to the point with the last sampling sequence number; the scale target point position = reference target point + distance scale value.

[0015] Furthermore, the specific method of looking up the distance scale value-amplitude ratio table to obtain the corresponding distance scale value and thus obtain the actual target distance value is:

[0016] The absolute value ratio of the amplitude values ​​of the points at two adjacent sampling numbers randomly selected in step 5 is recorded as bz′. Since the distance scale value-amplitude ratio table is monotonically decreasing within the range of the distance scale value, the two amplitude ratios closest to bz′ are found in the distance scale value-amplitude ratio table by binary search, which are bz1 and bz2, and the corresponding distance scale values ​​are ΔR1 and ΔR2, where bz1>bz2, ΔR1<ΔR2.

[0017] Furthermore, step 1 specifically includes the following steps:

[0018] Step 1.1, set the reference target position R1 and the maximum radar range MaxR, and generate a linear frequency modulation signal S(t);

[0019] The linear frequency modulation signal is defined as:

[0020]

[0021] Where S(t) is the linear frequency modulation signal, t is the time of the linear frequency modulation signal, T p is the pulse width, f c is the carrier frequency, γ is the modulation frequency, The rectangular window function is defined as:

[0022]

[0023] Divide S(t) into two paths and multiply them with the local oscillator signal to obtain I and Q signals. S i (t)=I(t)+jQ(t),S i (t) represents the echo signal of the linear frequency modulation signal S(t);

[0024] Step 1.2, with sampling frequency F s For the echo signal S i (t) is sampled to obtain the digital signal S i (n);

[0025] The digital signal S i (n) is defined as:

[0026]

[0027] Where n represents the number of sampling points, and the total number of sampling points N = T p F s , τ is the delay,

[0028] Furthermore, step 2 specifically includes the following steps:

[0029] Step 2.1: For the digital signal S i (n) Calculate the impulse response h(n) of the digital filter;

[0030] The impulse response h(n) is:

[0031]

[0032] in, Represents the digital signal S i conjugation of (n);

[0033] Step 2.2: Convert the digital signal S iThe I and Q signals of (n) are pulse compressed with the impulse response h(n) of the digital filter to obtain the first digital signal S o (n).

[0034] Furthermore, the sampling sequence number described in step 5 is defined as r+1 is the serial number of the next adjacent sampling point, where R nc Indicates the position of the scale target point

[0035] Furthermore, the pulse compression processing refers to respectively converting the digital signal S i The I and Q orthogonal signals of (n) and the matched digital filter impulse response are converted into the frequency domain by Fourier transform, and then converted into the time domain by inverse Fourier transform.

[0036] Furthermore, the windowing function in step 3 is specifically a Hamming function.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] (1) The amplitude ratio within the range unit of the noise-free linear frequency modulation signal is used to generate a range scale value-amplitude ratio table. When the noisy linear frequency modulation signal echo is obtained, the table is looked up to obtain the target position, thereby improving the radar target ranging accuracy and algorithm speed.

[0039] (2) The present invention uses a distance scale within a sampling distance to segment the distance near the signal center. The smaller the distance scale, the finer the segmentation. Thus, the generated amplitude ratio table is more accurate. In the final table lookup, the amplitude value is interpolated and calculated. The final ranging accuracy is less than the distance scale accuracy. This overcomes the problem in the prior art that only linear weighting of the distance amplitude is used, the sampling period is not considered, and the threshold selection of the low signal-to-noise ratio signal may lose some effective information of the signal, resulting in the final ranging result being unstable and the accuracy being not high enough. The target position measured by the present invention is more accurate and the error is smaller.

[0040] (3) The present invention generates a distance scale value-amplitude ratio table in advance, and the target position can be obtained by looking up the table after obtaining the target amplitude value. This overcomes the problem in the prior art that after setting a suitable threshold to obtain the target amplitude value, a linear weighted operation needs to be performed using the amplitude weighting formula, which increases the calculation time. The present invention improves the speed of distance measurement and better meets actual needs. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 It is a flow chart of implementing one of the present invention.

[0042] Figure 2 This is a linear frequency modulation signal diagram of the first embodiment of the present invention.

[0043] Figure 3 This is a distance scale value-amplitude ratio diagram obtained by processing in the first embodiment.

[0044] Figure 4 It is a distance measurement error diagram of 100 experiments obtained by using the present invention and the prior art at a signal-to-noise ratio of 20 dB.

[0045] Figure 5 It is a distance measurement error diagram of 100 experiments obtained by using the present invention and the prior art at a signal-to-noise ratio of 22 dB.

[0046] Figure 6 It is a distance measurement error diagram of 100 experiments obtained by using the present invention and the prior art at a signal-to-noise ratio of 24 dB.

[0047] Figure 7 This is a distance measurement error diagram of 100 experiments obtained by using the present invention and the prior art at a signal-to-noise ratio of 26 dB.

[0048] Figure 8 This is a distance measurement error diagram of 100 experiments obtained by using the present invention and the prior art at a signal-to-noise ratio of 28 dB.

[0049] Fig. 9 This is a distance measurement error diagram obtained by 100 experiments using the present invention and the prior art at a 30 dB signal-to-noise ratio.

[0050] Fig.10 It is a schematic diagram of the process of obtaining I and Q signals by dividing the linear frequency modulation signal into two paths and multiplying them with the local oscillator signal respectively.

[0051] Fig.11 It is a schematic diagram of the process of pulse compression processing of digital signals. DETAILED DESCRIPTION

[0052] The specific implementation of the pulse compression amplitude ratio ranging method of the present invention is described in detail below with reference to the accompanying drawings.

[0053] Embodiment 1

[0054] Reference Figure 1 The specific implementation steps of the present invention are as follows:

[0055] Step 1: Generate a linear frequency modulation signal and its echo signal without noise interference.

[0056] 1.1. Set the target position R1 and the maximum radar range MaxR to generate a linear frequency modulation signal S(t).

[0057] The target position R1 is set to 150km, the maximum range MaxR is set to 450km, and the linear frequency modulation signal is defined as:

[0058]

[0059] Where t is the time of the linear frequency modulation signal, T p is the pulse width, f c is the carrier frequency, γ is the modulation frequency, The rectangular window function is defined as:

[0060]

[0061] The linear frequency modulation signal S(t) is divided into two paths and multiplied with the local oscillator signal respectively to obtain the I and Q signals, as shown in Fig.10 shown.

[0062] in, S i (t)=I(t)+jQ(t),S i (t) represents the echo signal of the linear frequency modulation signal S(t).

[0063] 1.2, with sampling frequency F s For the echo signal S i (t) is sampled to obtain the digital signal S i (n).

[0064] The digital signal S i (n) is defined as:

[0065]

[0066] Where n represents the number of sampling points, and the total number of sampling points N = T p F s , τ is the delay.

[0067] Step 2: Perform pulse compression processing on the digital signal to obtain a first digital signal.

[0068] 2.1. For digital signal S i (n) Calculate the impulse response h(n) of the digital filter.

[0069] The impulse response h(n) is:

[0070]

[0071] in, Represents the digital signal S i The conjugate of (n).

[0072] 2.2、The digital signal S iThe I and Q signals of (n) are pulse compressed with the impulse response h(n) of the digital filter to obtain the first digital signal S o (n).

[0073] The pulse compression process is to convert the digital signal S i The I and Q orthogonal signals of (n) and the matched digital filter impulse response are transformed into the frequency domain by FFT (Fourier transform), and then transformed into the time domain by IFFT (inverse Fourier transform). The process is as follows: Fig.11 As shown;

[0074] Among them, I(n) and Q(n) are signal S i (n) two orthogonal signals, S oI (n) and S oQ (n) represent the signals of I(n) and Q(n) after FFT and IFFT transformation respectively.

[0075] Step 3: Select a windowing function to perform windowing processing on the first digital signal to reduce the signal side lobe and obtain a second digital signal.

[0076] 3.1. Select the windowing function to compress the echo signal S o (n) Processing is performed to reduce the side lobes of the output signal to obtain a second digital signal.

[0077] The windowing function can be expressed in the following general form:

[0078]

[0079] Wherein, B is the signal bandwidth, and f is the frequency of the windowed digital signal.

[0080] Different windowing functions have different K and n, for example, the Hamming function is when K = 0.08 and n = 2. Windowing is essentially a mismatch processing of the signal, and the Hamming window is used for windowing processing in this embodiment.

[0081] Step 4: Generate a distance scale value-amplitude ratio table.

[0082] 4.1. Within two sampling distance units centered at the reference target point R1 of the second digital signal, points are taken at a step interval of 0.2 m to generate a distance scale table, and the distance scale value is recorded as ΔR.

[0083] The distance scale table means that each sampling distance unit of the second digital signal is defined as: The range of the distance scale is: Right now Among them, V c represents the speed of light, represents the starting point of ΔR, Indicates the starting point of ΔR, and 0.2 is the step interval.

[0084] ΔR is slid on the distance scale in turn, with point R nc is the position of the scale target point, where R nc =R1+ΔR, repeat steps 1, 2 and 3, and record the sampling number r k With r k The ratio bz of the amplitude values ​​of the two points at +1 on the second digital signal is used to establish a distance scale value-amplitude ratio table of the second digital signal with respect to ΔR and bz, as shown in Table 1.

[0085] The sampling sequence number described in step 5 is defined as r+1 is the serial number of the next adjacent sampling point, where R nc Indicates the position of the scale target point

[0086] The amplitude ratio is specifically: sampling point number r k With r k The ratio of the absolute value of the amplitude of the +1 point on the second digital signal, the corresponding distance scale value-amplitude ratio table can be seen in Table 1.

[0087] ΔR(m) bz ΔR(m) bz ΔR(m) bz ΔR(m) bz -30.0000 3.1240 -24.2000 2.7393 20.2000 1.1851 70.2000 0.4870 -29.8000 3.1094 -24.0000 2.7273 20.4000 1.1810 70.4000 0.4851 -29.6000 3.0949 … … 20.6000 1.1769 70.6000 0.4832 -29.4000 3.0805 -6.8000 1.9232 … … … … … … -6.6000 1.9159 42.4000 0.8064 89.6000 0.3231 -24.6000 2.7635 -6.4000 1.9087 42.6000 0.8035 89.8000 0.3216 -24.4000 2.7514 … … … … 90.0000 0.3201

[0088] Table 1 Distance scale value-amplitude ratio table of the second digital signal

[0089] Step 5: Calculate the actual target distance value.

[0090] 5.1. ΔR is slid on the distance scale to obtain the value, with point R nc To mark the target point position, repeat steps 1, 2, and 3, where the digital signal S in step 1 is i (n) Add random Gaussian white noise, denoted by S n (n), the digital signal compressed in step 2 is recorded as S no (n); S no (n) obtaining a third digital signal after windowing in step 3;

[0091] 5.2. For the third digital signal, randomly select two points at adjacent sampling numbers, calculate the ratio of their absolute amplitudes bz′, look up the distance scale value-amplitude ratio table to obtain the corresponding distance and obtain the actual target distance value R 目标 .

[0092] The specific method of looking up the distance scale value-amplitude ratio table to obtain the corresponding distance to obtain the target position is: since the established distance scale value-amplitude ratio table is monotonically decreasing within the distance scale range (see Figure 3), so the two ratios bz1 and bz2 (bz1>bz2) closest to the ratio bz′ and the corresponding distances ΔR1 and ΔR2 (ΔR1<ΔR2) can be found in the table by using the dichotomy method. The actual target distance value can be calculated by interpolation using the following formula.

[0093]

[0094] Step 6: Statistical ranging error

[0095] 6.1. Repeat step 5 to perform 100 distance measurement experiments under different signal-to-noise ratio conditions, compare the target estimated distance scale value ΔR′ obtained by looking up the table each time with the scale value ΔR on the distance scale at that time, and calculate the distance measurement error of the present invention.

[0096] The signal-to-noise ratios under the different signal-to-noise ratio conditions are specifically 20dB, 22dB, 24dB, 26dB, 28dB and 30dB.

[0097] The statistical distance measurement error of the present invention is specifically: using the root mean square error (RMSE) to calculate the error value between the distance scale value ΔR on the distance scale table and the target estimated distance scale value ΔR′ obtained by the table lookup of the present invention, and the calculation formula is:

[0098]

[0099] 6.2. Under the different target signal-to-noise ratio conditions in step 6.1, use the existing ranging technology to conduct 100 ranging experiments, and calculate the target estimated distance obtained each time. The target position R on the distance scale at that time nc Compare and count the ranging errors of the prior art.

[0100] The specific method of the 100 distance measurement experiments is: for each scale target point position R nc The digital signal S no (n), calculate the maximum amplitude φ of the signal max And set the threshold Set the distance position whose amplitude is greater than or equal to the threshold is the target point, and the corresponding amplitude value is φ ti ,i=1,2,…,m, where i represents the i-th target point, with a total of m targets.

[0101] The target estimated distance can be obtained by linearly weighting the m targets using the existing technology. Defined as:

[0102]

[0103] The statistical prior art distance measurement error method is defined as:

[0104]

[0105] The effect of the present invention can be further illustrated by the following simulation.

[0106] 1. Simulation conditions:

[0107] The simulation test of the present invention is carried out in a hardware environment of an Intel(R) Core(TM) i5-6500 CPU with a main frequency of 3.2 GHz, a memory of 8 GB and a software environment based on Matlab.

[0108] 2. Simulation content:

[0109] The simulation of the present invention is based on Figure 1 The simulation experiment is carried out according to the flowchart. Figure 2 The parameters of the generated linear frequency modulation signal are: pulse interval T = 2.0 × 10 -5 (s), bandwidth B = 2.0 × 10 6 (Hz), sampling frequency F s =2.5×10 6 (Hz), carrier frequency f c =10×10 9 (Hz), noise-free signal S i The target position of (t) is R=150km, and the maximum effective range of the radar is MaxR=450km. Figure 4 , Figure 5 , Figure 6 , Figure 7 , Figure 8 and Fig. 9 The signal-to-noise ratio parameters of the linear frequency modulation signal for ranging are: 20dB, 22dB, 24dB, 26dB, 28dB and 30dB respectively.

[0110] 3. Simulation effect analysis:

[0111] The method of the present invention and the existing amplitude linear weighting method are used to carry out radar ranging experiments on linear frequency modulation echo signals under different signal-to-noise ratios as test data, and the root mean square error RMSE and test time are used as comparison standards. When the RMSE value is higher, the radar ranging accuracy is better, the test time is shorter, and the radar ranging speed is faster.

[0112] Available from Figure 4-Figure 9It can be seen that in the ranging experiment with the same signal-to-noise ratio, most of the distance scale accuracy of the method of the present invention is better than and far better than the prior art. Although the prior art has some distance scale accuracy better than the method of the present invention, it lacks stability and is not suitable for practical application. The ranging accuracy of the method of the present invention is higher; in the ranging experiments with different signal-to-noise ratios, the ranging accuracy results of the present invention are less affected, which is far better than the differences of the prior art under different signal-to-noise ratio experiments, indicating that the method of the present invention is more applicable in a low signal-to-noise ratio environment.

[0113] The test time results of the existing amplitude linear weighting technology method and the method of the present invention in simulation are shown in Table 2.

[0114] method Test time (seconds, 100 times) Amplitude linear weighting 0.1729 The present invention 0.0670

[0115] Table 2 Test time of the prior art method and the method of the present invention in simulation

[0116] The above results show that compared with the existing amplitude linear weighted ranging method, the present invention uses less test time.

[0117] In summary, the radar linear frequency modulation signal ranging method based on amplitude ratio proposed in the present invention improves the shortcomings of the above-mentioned existing methods, can improve the accuracy of radar target ranging, and increase the speed of target ranging.

[0118] The present invention uses a distance scale within a sampling distance to segment the distance near the signal center. The smaller the distance scale, the finer the segmentation. Thus, the generated amplitude ratio table is more accurate. In the final table lookup, the amplitude value is interpolated and calculated. The final distance measurement accuracy is less than the distance scale accuracy. This overcomes the problem that the prior art only uses linear weighting of the distance amplitude, does not consider the limitation of the distance measurement result caused by the sampling period, and does not consider that the threshold selection of the low signal-to-noise ratio signal may lose the effective information of part of the signal, resulting in the final distance measurement result being not stable enough and the accuracy being not high enough. Therefore, the target position measured by the present invention is more accurate and has a smaller error.

[0119] The present invention generates a distance scale value-amplitude ratio table in advance, and the target position can be obtained by looking up the table after the target amplitude value is obtained. This overcomes the problem in the prior art that after setting a suitable threshold to obtain the target amplitude value, a linear weighted operation needs to be performed using an amplitude weighting formula, which increases the calculation time. The present invention improves the speed of distance measurement and better meets actual needs.

[0120] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A pulse compression amplitude ratio ranging method, characterized in that: The following steps are involved: Step 1: Generate a linear frequency modulation signal and its echo signal without noise interference, sample the echo signal, and obtain a digital signal; Step 2: performing pulse compression processing on the digital signal to obtain a first digital signal; Step 3, selecting a windowing function to perform windowing processing on the first digital signal to reduce the signal side lobe to obtain a second digital signal; Step 4: generating a distance scale value-amplitude ratio table according to the second digital signal; the distance scale value-amplitude ratio table includes a plurality of distance scale values ​​and amplitude ratios corresponding thereto one by one; The specific method for obtaining the distance scale value is to select points within two sampling distance units centered on the reference target point of the second digital signal with a step length of M, and the value of any point is the distance scale value; The specific method for obtaining the amplitude ratio is to obtain the corresponding scale target point position according to the distance scale value and the reference target point, repeat steps 1-3, and calculate the ratio of the absolute values ​​of the amplitude values ​​of the points with two adjacent sampling numbers on the second digital signal, and the ratio of the amplitude values ​​is the amplitude ratio; Step 5: Calculate the actual target distance value: Add random Gaussian white noise to the digital signal in step 1; repeat steps 1-3 to obtain a third digital signal; For the third digital signal, arbitrarily select points at two adjacent sampling numbers, calculate the ratio of the absolute values ​​of their amplitude values, look up the distance scale value-amplitude ratio table to obtain the corresponding distance scale value, and thus obtain the actual target distance value.

2. The pulse compression amplitude ratio ranging method according to claim 1, characterized in that: The set of distance scale values ​​= ,in, is the sampling distance unit, , is the speed of light, is the sampling frequency when obtaining the digital signal from the echo signal , is the distance scale value corresponding to the point with the first sampling number, It is the distance scale value corresponding to the point with the last sampling sequence number; the scale target point position = reference target point + distance scale value.

3. The pulse compression amplitude ratio ranging method according to claim 2, characterized in that: The specific method of looking up the distance scale value-amplitude ratio table to obtain the corresponding distance scale value and thus obtain the actual target distance value is: The absolute value ratio of the amplitude values ​​of the points at two adjacent sampling numbers randomly selected in step 5 is recorded as Since the distance scale value-amplitude ratio table is monotonically decreasing within the range of the distance scale value, the binary search method is used to find the value that matches the distance scale value-amplitude ratio table. The two closest amplitude ratios are And the corresponding distance scale value is ,in, , , actual target distance value = .

4. The pulse compression amplitude ratio ranging method according to claim 3, characterized in that: Step 1 specifically includes the following steps: Step 1.1: Set the reference target position Maximum range of radar , generating a linear frequency modulation signal ; The linear frequency modulation signal is defined as: ;in, is a linear frequency modulation signal, is the time of the linear frequency modulation signal, is the pulse width, is the carrier frequency, To adjust the frequency, The rectangular window function is defined as: Will Divide into two paths and multiply them with the local oscillator signal respectively to get Two-way signal; among them, , , , Represents a linear frequency modulation signal The echo signal; Step 1.2, with sampling frequency For echo signal Sampling to obtain digital signal ; The digital signal Defined as: ;in, Indicates the number of sampling points, the total number of sampling points , For delay, .

5. The pulse compression amplitude ratio ranging method according to claim 4, characterized in that: Step 2 specifically includes the following steps: Step 2.1: For digital signals Compute the impulse response of a digital filter ; The impulse response for: in, Represents a digital signal conjugation of; Step 2.2: Convert digital signal of Two-way signal and impulse response of digital filter Perform pulse compression processing to obtain the first digital signal .

6. The pulse compression amplitude ratio ranging method according to claim 5, characterized in that: The sampling sequence number described in step 5 is defined as , That is, the sequence number of the next adjacent sampling point, where Indicates the location of the scale target point.

7. The pulse compression amplitude ratio ranging method according to claim 6, characterized in that: The pulse compression process refers to the process of converting the digital signal of The two orthogonal signals and the matched digital filter impulse response are converted to the frequency domain by Fourier transform, and then converted to the time domain by inverse Fourier transform.

8. The pulse compression amplitude ratio ranging method according to claim 7, characterized in that: The windowing function in step 3 is specifically a Hamming function.

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