CN110609276A - A Parabolic Antenna Broadband Monopulse Tracking Radar System - Google Patents

Abstract

The invention discloses a parabolic antenna broadband single-pulse tracking radar system, which belongs to the technical field of radar detection and tracking and can obtain more accurate target distance and angle measurement results. The system specifically includes: the transmitting subsystem generates and outputs a transmitting signal under the action of a radio frequency excitation signal. The antenna feeder system receives the target echo signal and outputs it after coupling correction. Under the control of the control information, the frequency synthesis subsystem generates radio frequency excitation signals to the transmitting subsystem, and generates receiving local oscillator signals to the receiving subsystem. The receiving subsystem obtains the target echo signal and receives the local oscillator signal for down-conversion processing to an intermediate frequency, and then outputs it to the signal processing subsystem. The signal processing subsystem digitally down-converts the target echo signal to the baseband, then performs amplitude and phase compensation and digital sum difference processing to obtain the sum channel signal, pitch difference channel signal and azimuth difference channel signal, and further obtain the distance and angle of the target Input to the display control subsystem for display.

Description

A Parabolic Antenna Broadband Monopulse Tracking Radar System

technical field

The invention relates to the technical field of radar detection and tracking, in particular to a parabolic antenna broadband single-pulse tracking radar system.

Background technique

With the development of science and technology, people's positioning of radar is not only to achieve target detection, the future war will be a four-dimensional war integrating sea, land, air and sky. Observation of debris and decoys will be the primary task of the radar. In order to meet the needs of complex scenarios such as space target detection and recognition, narrowband radar can no longer meet the needs of the current stage. Compared with narrowband radar, wideband radar can not only provide rich target information for detection, tracking and identification, but also has great significance for clutter suppression, electronic countermeasures, and anti-stealth target detection. For wideband radar, since the distance tracking measurement accuracy is much higher than the angle tracking accuracy, the angle measurement performance is an important factor that limits the high-precision target tracking of wideband radar. The existing radar angle measurement methods include sequential lobe method, cone scanning method, single pulse angle measurement method, etc. Among them, the single pulse angle measurement adopts the method of comparing antenna beams at the same time, which has the advantages of fast angle measurement speed and high angle measurement accuracy. Most radars use monopulse technology for angle measurement.

Compared with narrowband, wideband monopulse angle measurement faces more non-ideal factors, and is more sensitive to inconsistency in amplitude and phase between channels and even inconsistency in polarization, which is not conducive to the improvement of angle measurement accuracy. Regardless of the polarization characteristics of the antenna front end, there are mainly the following problems in wideband monopulse angle measurement:

First: Due to the high-resolution characteristics, the multi-scattering point target becomes a range-extending target, and the echo energy is dispersed to more range units and introduces greater noise power, so the signal-to-noise ratio on a single range unit will decrease (), resulting in deterioration of angle measurement performance;

Second: There are non-ideal factors such as amplitude and phase inconsistency among different channels of the system. The non-ideal factors can be divided into two categories: one is that the response of the antenna pattern at different frequency points of the broadband is inconsistent. Second, the broadband frequency response of each receiving channel is inconsistent.

The inconsistency of the antenna pattern and the frequency response of the back-end receiving channel will have a negative impact on the angle measurement. Under narrow-band conditions, the antenna pattern and the frequency response of the back-end receiving channel can be considered as an approximation of a single frequency point. At this time, the received baseband signal only has an amplitude phase error at this frequency point, which can be solved by multiplying the corresponding error compensation factor. Under broadband conditions, the amplitude and phase errors of the baseband signals passing through the antenna and receiving channel are different at different frequency points, and full-band compensation is required. On the other hand, the traditional amplitude and difference monopulse system uses a magic T mixer to perform sum and difference at the front end of the radio frequency or intermediate frequency, and then down-converts the three-channel signal of the sum and difference to the baseband angle measurement. If the antenna feeder before the summing device and the broadband frequency response of each receiving channel are inconsistent, it cannot be compensated after the summing and difference, which will affect the angle measurement accuracy.

Therefore, how to design a wideband monopulse tracking radar system so that it can obtain more accurate target distance and angle measurement results is an urgent problem to be solved.

Contents of the invention

In view of this, the present invention provides a parabolic antenna broadband monopulse tracking radar system, which can process the target signal and perform digital amplitude and phase compensation before summing and difference, so as to obtain more accurate target distance and angle measurement results .

In order to achieve the above object, the technical solution of the present invention is: a parabolic antenna broadband monopulse tracking radar system, including: antenna feeder subsystem, transmitting subsystem, frequency synthesis subsystem, receiving subsystem, signal processing subsystem and display control subsystem.

The transmitting subsystem is used to generate and output the transmitting signal under the action of the radio frequency excitation signal.

The antenna feeder system uses a parabolic antenna to receive the target echo signal and output it after coupling correction.

Under the control of the control information sent by the display control subsystem, the frequency synthesis subsystem generates a radio frequency excitation signal and outputs it to the transmitting subsystem to participate in the generation of the transmitting signal, and at the same time generates a receiving local oscillator signal and inputs it to the receiving subsystem.

The receiving subsystem obtains the target echo signal and receives the local oscillator signal for down-conversion processing to an intermediate frequency, and then outputs it to the signal processing subsystem.

The signal processing subsystem digitally down-converts the target echo signal to the baseband and compensates the amplitude and phase to obtain the amplitude-phase compensated signal, and then performs digital sum and difference processing on the amplitude-phase compensated signal to obtain the sum channel signal, The pitch difference channel signal and the azimuth difference channel signal, and finally obtain the distance and angle of the target according to the sum channel signal, pitch difference channel signal and azimuth difference channel signal and input them to the display control subsystem for display.

Further, the transmitting subsystem includes a power divider and a circulator, and after the transmitting subsystem generates the transmitting signal, it divides the transmitting signal into four paths through the power divider and outputs it through the circulator.

Furthermore, the antenna distribution system includes four horn feeds, four receiving channels and coupling correction channels; one of the horn feeds is connected to one receiving channel; the target echo signal enters the receiving channel through the horn feed; one receiving channel includes The secondary connected circulator, coupler and field effect tube; the coupling correction channel is specifically: the calibration signal source is respectively connected to the correction signal input terminals of the four couplers through power division, and the correction signal is input to the rear end through the couplers.

Further, the radio frequency excitation signal generated by the frequency synthesis sub-system includes: generating a transmission local oscillator signal and an intermediate frequency signal, and performing up-conversion to obtain a radio frequency excitation signal.

Further, the signal processing subsystem includes an intermediate frequency acquisition control module, an amplitude and phase compensation module, a digital sum and difference module, and a parameter estimation module.

The intermediate frequency acquisition control module digitally down-converts the target echo signal to baseband.

The amplitude and phase compensation module performs amplitude and phase compensation on the target echo signal of the digital baseband to obtain the amplitude and phase compensated signal.

The digital sum and difference module performs digital sum and difference on the signals after amplitude and phase compensation, and obtains the sum channel signal, the pitch difference channel signal and the azimuth difference channel signal.

The parameter estimation module obtains the distance and angle of the target according to the sum channel signal, pitch difference channel signal and azimuth difference channel signal.

Further, the four receiving channels are A channel, B channel, C channel and D channel respectively.

In the digital sum and difference module, the signals after amplitude and phase compensation correspond to the high-resolution range images of channel A, channel B, channel C and channel D respectively as p ₁ , p ₂ , p ₃ , and p ₄ .

Then the sum channel signal is the high-resolution distance image p _sum of the sum channel =p ₁ +p ₂ +p ₃ +p ₄ .

The azimuth difference channel signal is a high-resolution range image of the azimuth difference channel _{pa azi} =p ₁ +p ₄ -p ₂ -p ₃ .

The elevation difference channel signal is the elevation difference channel high-resolution range image p _ele =p ₁ +p ₂ −p ₃ −p ₄ .

Further, the amplitude and phase compensation module performs amplitude and phase compensation on the target echo signal of the digital baseband, and obtains the signal after the amplitude and phase compensation, specifically:

The transmitted signal is a frequency-step synthesized broadband signal; select channel 1 as the reference channel.

For the target echo signal of the digital baseband, obtain the intra-pulse amplitude phase error factor of the i-th sub-pulse of channel k relative to the i-th sub-pulse of the reference channel N is the number of frequency hopping points for synthesizing broadband signals in frequency steps.

where c _ki =A _1i /A _ki , A _1i is the amplitude value of the i-th sub-pulse of the reference channel, A _ki is the amplitude value of the i-th sub-pulse of the channel k, is the phase value of the ith sub-pulse of the reference channel, is the phase value of the ith sub-pulse of channel k.

Take t=iT _r +τ, i=0...N-1, T _r is the pulse repetition period of the frequency step synthesis broadband signal; τ is the target echo delay of the frequency step synthesis broadband signal; obtain the reference channel echo The maximum value of different sub-pulse amplitudes is Unwrap the phase of z' ₁ (iT _r +τ) to obtain the maximum unwrapped sub-pulse amplitude z″ ₁ (iT _r +τ), and the unwrapped sub-pulse amplitude maximum z″ ₁ (iT _r +τ) to perform amplitude and phase fitting to obtain the maximum value of the fitted sub-pulse amplitude z″ _fix (iT _r +τ).

Use z″ _fix (iT _r +τ) and z″ ₁ (iT _r +τ) to obtain pulse-to-pulse amplitude phase compensation factor

C _i exp{jΔφ _i }, i=1...N-1;

where C _i ＝|z″ _fix (iT _r +τ)|/|z″ ₁ (iT _r +τ)|, Δφ _i ＝angle{z″ _fix (iT _r +τ)}-angle{z″ ₁ ( iT _r +τ)};

angle{·} is the phase function.

Multiply the i-th sub-pulse of the k-th channel in the target echo signal of the digital baseband by the intra-pulse amplitude and phase compensation factor Multiplied by the pulse-to-pulse amplitude-phase compensation factor C _i exp{jΔφ _i } to obtain the amplitude-phase-compensated signal.

Beneficial effect:

The present invention provides a parabolic antenna broadband monopulse tracking radar system. Aiming at the requirements of wideband monopulse angle measurement, it is different from the traditional monopulse outputting and differencing three-channel signals after radio frequency or intermediate frequency summing and difference. The echo signal is frequency-converted to baseband, digital amplitude and phase compensation is performed after sampling, and then digital sum difference is performed on the compensated baseband signal, and finally angle measurement is performed by using the three-channel baseband signal after summing and difference. The broadband digital amplitude and phase compensation technology can solve the influence of broadband dispersion and amplitude and phase distortion on angle measurement. That is to say, the system provided by the present invention can have different amplitude and phase errors at different frequency points through the antenna and the baseband signal of the receiving channel under broadband conditions, and needs to perform full-band compensation; and can process the target signal and perform Amplitude and phase compensation are performed before digital summing to obtain more accurate target distance and angle measurements.

Description of drawings

Fig. 1 is a composition block diagram of the parabolic antenna broadband monopulse tracking radar system that the embodiment of the present invention provides;

Fig. 2 is a detailed structure diagram of the parabolic antenna broadband monopulse tracking radar system provided by the embodiment of the present invention.

Detailed ways

The present invention will be described in detail below with reference to the accompanying drawings and examples.

The present invention provides a parabolic antenna broadband monopulse tracking radar system. Aiming at the requirements of wideband monopulse angle measurement, it is different from the traditional monopulse outputting and differencing three-channel signals after radio frequency or intermediate frequency summing and difference. The echo signal is frequency-converted to baseband, digital amplitude and phase compensation is performed after sampling, and then digital sum difference is performed on the compensated baseband signal, and finally angle measurement is performed by using the three-channel baseband signal after summing and difference. The broadband digital amplitude and phase compensation technology can solve the influence of broadband dispersion and amplitude and phase distortion on angle measurement.

As shown in Figure 1, the parabolic antenna broadband monopulse tracking radar system provided by the embodiment of the present invention includes: antenna feeder subsystem, transmitting subsystem, frequency synthesis subsystem, receiving subsystem, signal processing subsystem and display control subsystem .

The transmitting subsystem is used to generate and output the transmitting signal under the action of the radio frequency excitation signal. In the embodiment of the present invention, the transmission subsystem includes a power divider and a circulator, and after the transmission subsystem generates a transmission signal, it divides the transmission signal into four channels through the power divider and outputs it through the circulator. as shown in picture 2.

The antenna feeder system uses a parabolic antenna to receive the target echo signal and output it after coupling correction.

In the embodiment of the present invention, the antenna feed distribution system includes four horn feed sources, four receiving channels and a coupling correction channel. as shown in picture 2.

One of the horn feeds is connected to a receiving channel; the target echo signal enters the receiving channel through the horn feed.

A receiving channel includes a circulator, a coupler and a field effect tube connected in sequence; the circulator and the coupler are used together for transceiver isolation.

The coupling correction channel is specifically: the calibration signal source is respectively connected to the correction signal input terminals of the four couplers through power division, and the correction signal is input to the rear end through the couplers.

Under the control of the control information sent by the display control subsystem, the frequency synthesis subsystem generates a radio frequency excitation signal and outputs it to the transmitting subsystem to participate in the generation of the transmitting signal, and at the same time generates a receiving local oscillator signal and inputs it to the receiving subsystem.

In the embodiment of the present invention, the radio frequency excitation signal generated by the frequency synthesis and separation system includes: generating a transmission local oscillator signal and an intermediate frequency signal, and performing up-conversion to obtain a radio frequency excitation signal.

The receiving subsystem obtains the target echo signal and receives the local oscillator signal for down-conversion processing to an intermediate frequency, and then outputs it to the signal processing subsystem.

The signal processing subsystem digitally down-converts the target echo signal to the baseband and compensates the amplitude and phase to obtain the amplitude-phase compensated signal, and then performs digital sum and difference processing on the amplitude-phase compensated signal to obtain the sum channel signal, The pitch difference channel signal and the azimuth difference channel signal, and finally obtain the distance and angle of the target according to the sum channel signal, pitch difference channel signal and azimuth difference channel signal and input them to the display control subsystem for display.

The signal processing subsystem includes the intermediate frequency acquisition control module, the amplitude and phase compensation module, the digital sum difference module and the parameter estimation module.

The intermediate frequency acquisition control module performs digital down-conversion to the baseband of the target echo signal; specifically, it can also include a pulse compression process.

The amplitude and phase compensation module performs amplitude and phase compensation to the target echo signal of the digital baseband, and obtains the signal after the amplitude and phase compensation;

The digital sum and difference module performs digital sum and difference on the signal after amplitude and phase compensation, and obtains the sum channel signal, the elevation difference channel signal and the azimuth difference channel signal;

The parameter estimation module obtains the distance and angle of the target according to the sum channel signal, pitch difference channel signal and azimuth difference channel signal, wherein the angle includes azimuth angle and pitch angle.

Embodiments of the present invention illustrate the specific modules of the signal processing subsystem in the system where the transmitted signal is a frequency-step synthesized broadband signal:

The general model for synthesizing broadband signals with frequency steps is:

Where t is the time axis, u(t) is the sub-pulse baseband modulation signal, and T _r is the pulse repetition period (PulseRepetition Time, PRT).

f _i =f ₀ +iΔf is the carrier frequency of the i-th sub-pulse, f ₀ is the start frequency of frequency hopping, Δf is the frequency hopping interval between pulses, and N is the number of frequency hopping points.

For the radar system adopting the wideband digital and differential monopulse technology of the new system in this patent, when the ideal static point target is located at the center of the boresight of the antenna, the echo signals received by each channel are respectively

Among them, k={1,2,3,4} represents 4 receiving channels; A _ki represents the kth receiving channel, the echo amplitude of the i-th sub-pulse; Represents the echo phase error of the k-th receiving channel and the i-th sub-pulse; τ represents the target echo delay. The meanings of other symbols are the same as formula (1). After the frequency is down-converted by the receiving subsystem, and the frequency is down-converted to the baseband by the intermediate frequency acquisition control module, the baseband echo signal of each channel becomes

The intermediate frequency acquisition control module can also carry out the pulse compression of the sub-pulse. After the pulse compression of the sub-pulse, the baseband echo signal of each channel becomes

where sinc(·) is the complex envelope of the sub-pulse after pulse compression. Taking t=iT _r +τ, the maximum value of the different sub-pulse amplitudes of the echoes of each channel is obtained as Perform the inverse discrete Fourier transform IDFT{ } on z' _k (iT _r +τ) to obtain the high-resolution one-dimensional range image of each channel as

When there is no amplitude and phase error in each channel and the ideal static point target is located at the center of the boresight of the antenna, A _ki = A _qm in formula (5), k≠q, i≠m are constants, and It can be seen from formula (5) that the high-resolution one-dimensional range image of each channel at this time is

From (6) and the above analysis, it can be known that _pazi (n) and _pele (n) are 0 at this time, and the measured values of azimuth and pitch angle are both 0°.

When there are different amplitude and phase errors in each channel, there will be errors in the angle measurement. It is necessary to compensate the amplitude and phase errors of each channel first, and then measure the angle. Considering that the sub-pulse bandwidth of the frequency step synthesized wideband signal is smaller than the synthesized bandwidth, the amplitude and phase compensation module can use the following method to compensate the amplitude and phase error of the target echo signal of the digital baseband:

The transmitted signal is a frequency step synthesized broadband signal; select channel 1 as the reference channel;

For the target echo signal of the digital baseband, obtain the intra-pulse amplitude phase error factor of the i-th sub-pulse of channel k relative to the i-th sub-pulse of the reference channel N is the number of frequency hopping points for synthesizing broadband signals in frequency steps;

where c _ki =A _1i /A _ki , A _1i is the amplitude value of the i-th sub-pulse of the reference channel, A _ki is the amplitude value of the i-th sub-pulse of the channel k, is the phase value of the ith sub-pulse of the reference channel, is the phase value of the ith sub-pulse of channel k;

Take t=iT _r +τ, i=0...N-1, T _r is the pulse repetition period of the frequency step synthesis broadband signal; τ is the target echo delay of the frequency step synthesis broadband signal; obtain the reference channel echo The maximum value of different sub-pulse amplitudes is Unwrap the phase of z′ ₁ (iT _r +τ) to obtain the maximum unwrapped sub-pulse amplitude z″ ₁ (iT _r +τ), and the unwrapped sub-pulse amplitude maximum z″ ₁ (iT _r +τ) for amplitude and phase fitting to obtain the maximum value of the fitted sub-pulse amplitude z″ _fix (iT _r +τ), then it is considered that z″ _fix (iT _r +τ) is consistent with the target echo pulse without error The amplitude and phase are basically consistent. In the embodiments of the present invention, the target echo pulse-to-pulse amplitude and phase errors obtained by the fitting method are statistically the smallest.

Use z″ _fix (iT _r +τ) and z″ ₁ (iT _r +τ) to obtain pulse-to-pulse amplitude phase compensation factor

C _i exp{jΔφ _i }, i=1...N-1;

where C _i ＝|z″ _fix (iT _r +τ)|/|z″ ₁ (iT _r +τ)|, Δφ _i ＝angle{z″ _fix (iT _r +τ)}-angle{z″ ₁ ( iT _r +τ)};

angle{ } is the phase function;

Multiply the i-th sub-pulse of the k-th channel in the target echo signal of the digital baseband by the intra-pulse amplitude and phase compensation factor Then, multiplied by the pulse-to-pulse amplitude-phase compensation factor C _i exp{jΔφ _i } to obtain the amplitude-phase-compensated signal. Using this method to perform amplitude-phase compensation, the inter-pulse amplitude and phase errors of the amplitude-phase-compensated signal are statistically smallest, and the digital sum difference of the amplitude-phase-compensated signal can be used to obtain more accurate angle measurement results.

In the embodiment of the present invention, the four receiving channels are respectively A channel, B channel, C channel and D channel;

In the digital sum-difference module, the high-resolution distance images of the A-channel, B-channel, C-channel and D-channel corresponding to the signal after amplitude and phase compensation are p ₁ , p ₂ , p ₃ , p ₄ ;

Then the sum channel signal is the high-resolution distance image p _sum of the sum channel = p ₁ +p ₂ +p ₃ +p ₄ ;

The azimuth difference channel signal is the high-resolution range image of the azimuth difference channel _{pa azi} = p ₁ +p ₄ -p ₂ -p ₃ ;

The elevation difference channel signal is the elevation difference channel high-resolution range image p _ele =p ₁ +p ₂ −p ₃ −p ₄ .

On the basis of the echo data of each channel after compensation, high-resolution imaging is carried out for each channel, and the azimuth and elevation angle are measured by using the frequency-step synthesis broadband signal single-pulse angle measurement model.

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

Claims (7)

1. A parabolic antenna broadband monopulse tracking radar system, comprising: the system comprises an antenna feed subsystem, a transmitting subsystem, a frequency synthesis subsystem, a receiving subsystem, a signal processing subsystem and a display control subsystem;

the transmitting subsystem is used for generating and outputting a transmitting signal under the action of a radio frequency excitation signal;

the antenna feed subsystem receives a target echo signal by adopting a parabolic antenna, performs coupling correction and outputs the signal;

the frequency integration subsystem generates a radio frequency excitation signal under the control of the control information sent by the display control subsystem, outputs the radio frequency excitation signal to the transmitting subsystem to participate in the generation of a transmitting signal, and simultaneously generates a receiving local oscillator signal and inputs the receiving local oscillator signal to the receiving subsystem;

the receiving subsystem obtains the target echo signal and the receiving local oscillator signal, performs down-conversion processing on the target echo signal and the receiving local oscillator signal to an intermediate frequency, and outputs the intermediate frequency to the signal processing subsystem;

the signal processing subsystem performs digital down-conversion on the target echo signal to a baseband, then performs amplitude and phase compensation to obtain an amplitude-phase compensated signal, then performs digital sum and difference processing on the amplitude-phase compensated signal to obtain a sum channel signal, a pitch difference channel signal and an azimuth difference channel signal, and finally obtains the distance and the angle of the target according to the sum channel signal, the pitch difference channel signal and the azimuth difference channel signal and inputs the distance and the angle to the display control subsystem for display.

2. The radar system of claim 1 wherein the transmit subsystem includes a power divider and a circulator, and wherein the transmit subsystem generates the transmit signal and then divides the transmit signal into four paths through the power divider and outputs the four paths through the circulator.

3. The system of claim 2, wherein the antenna feed subsystem comprises four horn feeds, four receive channels, and a coupling correction channel;

one of the horn feed sources is connected with one of the receiving channels; the target echo signal enters the receiving channel through the horn feed source;

one receiving channel comprises a circulator, a coupler and a field effect tube which are connected in sequence;

the coupling correction channel specifically comprises: and the signal source for calibration is respectively connected to the input ends of the calibration signals of the four couplers through power division, and the calibration signals are input to the rear end through the couplers.

4. The system of claim 1, wherein the radio frequency excitation signal generated by the frequency integration system comprises: and generating a transmitting local oscillator signal and an intermediate frequency signal, and performing up-conversion to obtain the radio frequency excitation signal.

5. The system of any one of claims 1 to 4, wherein the signal processing subsystem comprises an intermediate frequency acquisition control module, a magnitude and phase compensation module, a digital sum and difference module, and a parameter estimation module;

the intermediate frequency acquisition control module performs digital down-conversion on the target echo signal to a baseband;

the amplitude and phase compensation module compensates the amplitude and phase of a target echo signal of the digital baseband to obtain an amplitude and phase compensated signal;

the digital sum and difference module is used for carrying out digital sum and difference on the amplitude-phase compensated signals to obtain sum channel signals, pitch difference channel signals and azimuth difference channel signals;

and the parameter estimation module acquires the distance and the angle of the target according to the sum channel signal, the pitch difference channel signal and the azimuth difference channel signal.

6. The system of claim 5, wherein the four receive channels are a channel, B channel, C channel, and D channel, respectively;

in the digital sum and difference module, the high-resolution distance images of the signals after amplitude and phase compensation corresponding to the channel A, the channel B, the channel C and the channel D are respectively p₁、p₂、p₃、p₄；

Then the sum channel signal is the high resolution range profile p of the sum channel_sum＝p₁+p₂+p₃+p₄；

High resolution range profile p with azimuth difference channel signal as azimuth difference channel_azi＝p₁+p₄-p₂-p₃；

The pitch difference channel signal is a pitch difference channel high-resolution range profile p_ele＝p₁+p₂-p₃-p₄。

7. The system of claim 6, wherein the amplitude and phase compensation module performs amplitude and phase compensation on the target echo signal of the digital baseband to obtain an amplitude and phase compensated signal, specifically:

the transmitting signal is a frequency stepping synthesis broadband signal; selecting a channel 1 as a reference channel;

aiming at a target echo signal of a digital baseband, acquiring an intra-pulse amplitude phase error factor of the ith sub-pulse of a k channel relative to the ith sub-pulse of a reference channelN is the number of frequency hopping points of the frequency stepping synthesis broadband signal;

wherein c is_ki＝A_1i/A_ki、A_1iIs the amplitude value of the ith sub-pulse of the reference channel, A_kiThe amplitude value of the ith sub-pulse of channel k,is the phase value of the ith sub-pulse of the reference channel,The phase value of the ith sub-pulse of the channel k;

get t ═ iT_r+τ,i＝0…N-1，T_rSynthesizing a pulse repetition period of the wideband signal for said frequency steps; tau is the target echo time delay of the frequency stepping synthesis broadband signal; obtaining the maximum value of the amplitudes of different sub-pulses of the echo of the reference channel asTo z'₁(iT_r+ tau) phase is unwrapped to obtain the maximum value z of amplitude of unwrapped sub-pulse "₁(iT_r+ tau), maximum value z of amplitude of the unwrapped subpulse "₁(iT_r+ tau) amplitude and phase fitting to obtain the maximum value z of the fitted sub-pulse amplitude "_fix(iT_r+τ)；

By z "_fix(iT_r+ tau) and z "₁(iT_r+ tau) may obtain the inter-pulse amplitude phase compensation factor

C_iexp{jΔφ_i},i＝1…N-1；

Wherein C is_i＝|z”_fix(iT_r+τ)|/|z”₁(iT_r+τ)|，Δφ_i＝angle{z”_fix(iT_r+τ)}-angle{z”₁(iT_r+τ)}；

angle {. is a phase taking function;

multiplying ith sub-pulse of k channel in target echo signal of digital baseband by in-pulse amplitude phase compensation factorThen multiplied by an inter-pulse amplitude phase compensation factor C_iexp{jΔφ_iAnd obtaining the signals after amplitude and phase compensation.