CN103675772A - A multifunctional SAR complex electromagnetic environment simulator - Google Patents

Abstract

Translated fromChinese

一种多功能SAR复杂电磁环境模拟装置，包括天线与微波分系统、基带干扰信息产生及调制单元、控制显示与模型单元。天线与微波分系统获得SAR雷达发射信号，进行功率调整和多级下变频后输出给基带干扰信息产生及调制单元，同时将基带干扰信息产生及调制单元输出的中频干扰信号，进行多级上变频和功率控制后输出给SAR雷达。基带干扰信息产生及调制单元根据接收的控制命令及参数，实时计算产生多种干扰类型的基带调制信息，将基带调制信息与中频雷达信号经过调制后产生所需的干扰信号。控制显示与模型单元根据模拟要求调用干扰模型产生干扰参数送至基带干扰信息产生及调制单元，同时对整个模拟装置的运行状态进行监控和参数记录。

A multifunctional SAR complex electromagnetic environment simulation device includes an antenna and a microwave subsystem, a baseband interference information generation and modulation unit, a control display and a model unit. The antenna and microwave subsystem obtains the SAR radar transmission signal, performs power adjustment and multi-stage down-conversion, and then outputs it to the baseband interference information generation and modulation unit, and at the same time, performs multi-stage up-conversion on the intermediate frequency interference signal output by the baseband interference information generation and modulation unit And output to SAR radar after power control. The baseband interference information generation and modulation unit calculates and generates baseband modulation information of various interference types in real time according to the received control commands and parameters, and modulates the baseband modulation information and the intermediate frequency radar signal to generate the required interference signal. The control display and model unit calls the interference model according to the simulation requirements to generate interference parameters and sends them to the baseband interference information generation and modulation unit, and at the same time monitors the operating status of the entire simulation device and records parameters.

Description

A kind of multi-functional SAR complex electromagnetic environment analogue means

Technical field

The invention belongs to the communications field, relate to a kind of SAR electromagnetic environmental simulator.

Background technology

Synthetic-aperture radar (english abbreviation is SAR) has round-the-clock, round-the-clock detection imaging and strong perspectivity, high resolving power, good features such as antijamming capability, and these features make SAR be widely used at aerospace field.In actual use, SAR may face from the complex electromagnetic environment in space environment and disturb, and therefore need before the sizing of SAR product technology state, to its electromagnetic environment adaptive faculty, test examination.

The at present adaptability examination to complex electromagnetic environment for SAR, is mainly hung and is flown and the real isotype that flies of aerospace vehicle by aircraft outfield, and experimentation cost is high, it is huge to spend.The technical literature of abroad publishing there is no the relevant report that SAR electromagnetic environment adaptability is examined the research of indoor equivalent substitution method.In domestic technique document, the Design and Analysis > > that is published in the < < radar interference simulator of < < defense technology basis > > in November, 2010 set forth a kind of composition and basic functional principle of radar interference simulator from ultimate principle, but its narration is comparatively simple, and comprehensive covering of not carrying out complex electromagnetic environment for mode of operation and the feature of SAR.

Therefore, for SAR in the indoor concrete application of carrying out the equivalence examination of complex electromagnetic environment adaptability, need to research and develop a kind of equivalent simulation device, by applying different types of electromagnetic environment, disturb, examination SAR is in the adaptive capacity to environment of specifying in interference type or many interference types stack situation.

Summary of the invention

Technology of the present invention is dealt with problems and is: overcome the deficiencies in the prior art, a kind of multi-functional SAR complex electromagnetic environment analogue means is provided, according to the mode of operation of SAR and scene parameter, receiving radar transmits in real time, by the mode of space radiation or straight feed cable coupling, simulate the space electromagnetic interference signal from different directions, all kinds stack, for the Anti-jamming effectiveness test of SAR.

Technical solution of the present invention is: a kind of multi-functional SAR complex electromagnetic environment analogue means, and comprise antenna and microwave subsystem, the generation of base band interfere information and modulating unit, the real-time figure collecting unit of SAR, control demonstration and model unit, wherein:

Antenna and microwave subsystem: comprise electromagnetic horn, radio-frequency cable, AGC unit, multistage down-converter unit, frequently comprehensive unit, multistage up-conversion unit, power adjustment unit; SAR radar emission signal receives by electromagnetic horn space or delivers to AGC unit by radio-frequency cable, AGC unit carries out delivering to multistage down-converter unit after power adjustment to SAR radar emission signal, and the SAR radar emission signal of multistage down-converter unit after to power adjustment carries out obtaining if radar signal and export to base band interfere information producing and modulating unit after two-stage down coversion; Multistage up-conversion unit carries out delivering to power adjustment unit after two-stage up-conversion to the middle frequency interference signal that base band interfere information produces and modulating unit generates, the middle frequency interference signal of power adjustment unit after to up-conversion carries out obtaining Radio Frequency Interfere after power adjustment, and Radio Frequency Interfere is delivered to SAR radar by electromagnetic horn space radiation or by radio-frequency cable; Frequently combining unit provides work required frequency signal for multistage up-conversion unit and multistage down-converter unit, for base band interfere information produces and modulating unit provides work clock;

Base band interfere information produces and modulating unit: comprise instantaneous frequency measurement unit, the real-time computing unit of interfere information, the real-time modulating unit of interfere information; The real-time computing unit of interfere information shows according to controlling the interference parameter transmitting with model unit, produces the baseband modulation information of corresponding interference type; Instantaneous frequency measurement unit obtains the frequency of if radar signal by the method for digital Frequency Measuring; The real-time modulating unit of interfere information produces required middle frequency interference signal by baseband modulation information according to the frequency of if radar signal and if radar signal and delivers to the generation of base band interfere information and modulating unit after ovennodulation;

The real-time figure collecting unit of SAR: receive SAR realtime graphic and deliver to and control demonstration and model unit by LVDS interface;

Control and show and model unit: comprise interface control and display unit, interference model unit; Compacting interference model, cheating interference model, relevant interference model, chaff interference model, noise jamming model have been stored in interference model unit, call corresponding interference model produce corresponding interference parameter and deliver to the real-time computing unit of interfere information according to the disturbed condition of outside input; According to the disturbed condition of outside input, the power of power adjustment unit is controlled; Image and real image that SAR radar is generated under disturbed condition are compared, and obtain SAR interference effect; The running status of whole analogue means is monitored and reference record.

Described multistage down-converter unit comprises two frequency mixer, automatic gain control device, low-pass filter; 12～18GHz radiofrequency signal of SAR radar emission is carried out first order down coversion with the local oscillation signal of frequency range 12～16GHz that frequently comprehensive unit provides by the first frequency mixer, obtains 2GHz the first intermediate-freuqncy signal; The first intermediate-freuqncy signal is after automatic gain control device carries out automatic gain control, second level down coversion is carried out in the local oscillation signal mixing of the 2.5GHz providing by the second frequency mixer and frequently comprehensive unit, and the signal after the down coversion of the second level obtains the if radar signal of 500 ± 250MHz after low-pass filter.

Described multistage up-conversion unit comprises two frequency mixer, bandpass filter, switch filter group, two amplifiers and attenuator, 2.5GHz local oscillation signal mixing in three-mixer that middle frequency interference signal and frequently comprehensive unit provide obtains the signal of 2GHz frequency, the signal of 2GHz frequency is delivered to the 4th frequency mixer after amplifying by band-pass filter and the first amplifier, in the 4th frequency mixer, the signal of 2GHz centre frequency obtains with 12～16GHz local oscillation signal mixing that frequently comprehensive unit provides the signal that centre frequency is 12～18GHz, signal bandwidth is the M signal of 500MHz, M signal is met 12～18GHz signal of purity requirement after by the corresponding frequency range of switch filter group filtering, 12～18GHz the signal that meets purity requirement is decayed and is carried out obtaining required Radio Frequency Interfere after power amplification with the second amplifier through programmable attenuator successively.

The present invention's advantage is compared with prior art:

(1) apparatus of the present invention are separated with the generation of base band interfere information and modulating unit by interference model, interference model can separate configurations, jamming signal type is many, can select flexibly interference type, and can realize the simulation that pressing type interference, cheating interference, relevant interference, noise jamming and chaff disturb the combined type undesired signal of five types of interference simultaneously, form complex electromagnetic environment, effectively reduce volume and the cost of hardware device simultaneously;

(2) undesired signal of apparatus of the present invention simulations can be injected or the mode of space radiation is received by radar by radio frequency, use-pattern is flexible, interfering signal power is flexible configuration according to the actual requirements, effectively simulates the action effect of various jamming emitters under various operating distance;

(3) apparatus of the present invention possess SAR real time image collection function, for assessment, compare SAR image Output rusults under various electromagnetic environments condition is provided;

(4) the present invention is according to the super wide feature of SAR bandwidth of operation, frequently the two-stage local oscillation signal of combining output based on broadband carries out multistage down coversion control, multistage upconversion process to radiofrequency signal, so that equipment adapts to wider frequency band range, the system that simultaneously guarantees provides higher spuious inhibition level in ultra wide band frequency.

Accompanying drawing explanation

Fig. 1 is the theory of constitution block diagram of apparatus of the present invention;

Fig. 2 is the theory of constitution block diagram of the multistage down-converter unit of the present invention;

Fig. 3 is the theory of constitution block diagram of the multistage up-conversion of the present invention unit;

Fig. 4 is that the present invention combines the theory of constitution block diagram of unit frequently;

Fig. 5 is that the real-time figure collecting unit of SAR of the present invention forms schematic diagram.

Embodiment

As shown in Figure 1, multi-functional SAR complex electromagnetic environment analogue means of the present invention is comprised of following subsystem: antenna and microwave subsystem, the generation of base band interfere information and modulating unit, the real-time figure collecting unit of SAR, control show and model unit.

Antenna and microwave subsystem mainly by electromagnetic horn, radio-frequency cable, multistage down coversion, AGC, multistage up-conversion, power adjustment, power splitter, frequently the module such as combine and form.The major function of this subsystem has two parts, first obtains SAR radar emission signal by the mode that space receives or line is presented, and this signal is carried out to power adjustment and multistage down coversion, then if radar signal is exported to base band interfere information and produced and modulating unit.Second portion is by the middle frequency interference signal that base band interfere information produces and modulating unit is exported, and carries out multistage up-conversion and power and controls, and then, by the mode of aerial radiation or line feedback, exports to tested SAR radar.

Base band interfere information produces and modulating unit comprises that instantaneous frequency measurement, interfere information calculate in real time and several ingredients such as interfere information modulation in real time.According to the control command and the parameter that receive, the real-time computing module of interfere information can produce the baseband modulation information of multiple interference type, comprises that pressing type interference, cheating interference, relevant interference, noise jamming and chaff disturb; Instantaneous frequency measurement can provide by digital Frequency Measuring algorithm the frequency of if radar signal, and digital Frequency Measuring algorithm is the broadband single-bit instantaneous frequency measurement reception technique > > based on Real-time digital signal processing referring to the < < that is published in < < marine electronic antagonism > > in March, 2012; The real-time modulation module of interfere information for producing required undesired signal by the interfere information calculating in real time and the if radar signal frequency information of instantaneous frequency measurement gained after ovennodulation, and it comprises the links such as broadband signal AD collection, Digital Down Convert, the modulation of base band interfere information, Digital Up Convert and broadband DA.

The real-time figure collecting unit of SAR receives SAR realtime graphic by LVDS interface, and image and the real image that can under disturbed condition, generate radar are compared, by disturbing evaluating software to assess SAR interference effect.

Control to show with model unit and mainly by interface control and demonstration and two major parts of interference model, formed.Interference model calculates the parameter of required various types of interfere informations according to interface parameters, and parameter is handed down to the generation of base band interfere information and modulating unit; According to parameters such as the jamming power arranging, undesired signal frequencies, antenna and microwave subsystem are controlled; The running status of whole analogue means is monitored and reference record.

The principle of work of system is: before emulation starts, operator shows by control and interference model unit, complete the setting of disturbing decision-making and interference parameter, interference model, according to the parameter arranging and corresponding model, generates control command and exports to the generation of base band interfere information and modulating unit.Antenna and microwave sub-system, adopt the mode receiving radar radiofrequency signal of empty feedback or line feedback, and lower powered radar radiofrequency signal, after overpower is adjusted, carries out that down-converted obtains radar intermediate frequency signal to carry out the collection of signal.Base band interfere information produces and modulating unit utilizes A/D to gather radar signal, by after instantaneous frequency measurement, Digital Down Convert for carrying out convolution with interference parameter, interference parameter mainly calculates (compacting interference etc. directly produces according to model, need not carry out convolution) by the real-time computing module of interfere information according to control command.After convolution, generate undesired signal through after D/A conversion, export to antenna and microwave subsystem, by antenna and microwave subsystem, complete up-conversion and filtering, power amplification and power are controlled, finally by line, present or the mode of space radiation is exported to tested radar.The real-time figure collecting unit of SAR receives SAR realtime graphic by LVDS interface, and SAR interference effect is assessed.

As shown in Figure 2, be the composition frame chart of multistage down-converter unit in antenna and microwave subsystem.12～18GHz radiofrequency signal of SAR transmitting and the local oscillation signal of frequency range 12～16GHz carry out first order down coversion, obtain 2GHz the first intermediate-freuqncy signal; The first intermediate-freuqncy signal, after automatic gain is controlled, is carried out second level down coversion, with local oscillation signal mixing, the low-pass filtering of 2.5GHz, obtains 500 ± 250MHz the second intermediate-freuqncy signal (if radar signal), offers base band interfere information and produces and modulating unit.

As shown in Figure 3, multistage up-conversion unit is used for base band interfere information to produce and the frequency interference signal of modulating unit is converted to Radio Frequency Interfere, and controls interfering signal power.First order frequency conversion, the local oscillation signal mixing of middle frequency interference signal and 2.5GHz obtains the signal of 2GHz frequency; In the frequency conversion of the second level, after amplifying after filtering, the signal of 2GHz centre frequency obtains with the 12～16GHz local oscillation signal mixing that comes self-frequency to combine the signal that centre frequency is 12～18GHz, signal bandwidth is 500MHz, then by the corresponding frequency range of switch filter group filtering, can obtain the signal of 12～18GHz of the required purity of frequency spectrum, finally by process controlling attenuation, control and power amplification, just can obtain required Radio Frequency Interfere.

As shown in Figure 4, the synchronizing signal of utilizing SAR is combined in broadband frequently, the variable bandwidth local oscillator and the intermediate frequency that provide the required synchronous clock of the generation of base band interfere information and modulating unit and frequency conversion link to need; Also can utilize the crystal oscillator carrying to provide synchronous clock and local oscillator and intermediate frequency as benchmark.Broadband is frequently combined and is adopted mixing phaselock technique, wherein with reference to phaselocked loop, produces little stairstep signal, and signal is inputted main phaselocked loop after treatment; Local oscillator ring produces large stairstep signal, and inputs main ring after four frequency division output signal mixing of RF Voltage-Controlled Oscillator; Main ring is controlled the frequency range that phase-locked polarity is selected locking, produces voltage signal Vt and controls RF Voltage-Controlled Oscillator; Voltage controlled oscillator output signal is after frequency multiplication and Frequency Band Selection, through the output of amplifier balanced device.Amplifier is for amplifying signal and providing certain power, balanced device to guarantee the flatness of signal in bandwidth.

The ultrabroad band double-ridged horn antenna that antenna is selected has extremely wide frequency bandwidth, high gain.Frequency coverage is greater than an octave.

Base band interfere information produces and modulating unit gathers the Low Medium Frequency radar emission broadband signal of multistage down-converter unit output, carries out instantaneous frequency measurement, Digital Down Convert, and with interfere information convolution, Digital Up Convert, DA output Low Medium Frequency undesired signal; Produce compacting undesired signal, comprise aiming formula noise, block type noise, sweep-frequency Békésy audiometer noise, cover impulse disturbances, this type of signal and radar emission signal are irrelevant; Produce relevant interference signal, comprise Convolution Noise, Doppler's noise and intensive copying, this type of signal and radar emission signal correction; Produce cheating interference signal, comprise point target and Area Objects, this type of signal and radar emission signal correction; Produce chaff and land clutter undesired signal, this type of signal and radar emission signal coherence.

Base band interfere information produces and modulating unit is controlled reception if radar signal, becomes the baseband signal that includes SAR signal characteristic through analog to digital conversion, Digital Down Convert; The real-time computing module of interfere information receives interference signal parameters, generates corresponding compacting interference, relevant, cheating interference model; Under the control of synchronous clock, the interference model that the real-time computing module utilization of interfere information generates is modulated including the baseband signal of SAR signal characteristic, obtains playing to SAR the baseband interference signal of interference effect; Baseband interference signal obtains middle frequency interference signal after Digital Up Convert, digital-to-analog conversion, delivers to follow-up multistage upconverter.

As shown in Figure 5, the real-time figure collecting unit of SAR adopts LVDS interface to adopt the high-speed high capacity realtime image data of SAR output, and LVDS interface chip clock frequency is 12MHz, and bus transfer code check is 144Mbps.

Controlling the effect showing with model unit is that undesired signal type, undesired signal frequency and the power etc. of simulation are controlled, and can monitor and reference record the running status of whole device; And interference model will calculate the required various types of interfere information calculating parameters of Base Band Unit work according to interface parameters.

Below various interference models are described in detail.

1, compacting is disturbed

Compacting is disturbed and is comprised that aiming formula noise, block type noise, sweep-frequency Békésy audiometer noise, covering impulse disturbances and comb spectrum disturb.Dredge shape spectrum interference model with reference to being published in the comb spectrum interference simulation research > > realization of the < < of < < Computer Simulation > > without carrier frequency ULTRA-WIDEBAND RADAR in June, 2008, block type noise, aiming formula noise, sweep-frequency Békésy audiometer noise, cover the compacting interference models such as impulse disturbances with reference to the master thesis < < of University of Electronic Science and Technology in 2010 radar active based on FPGA disturb generating technique research > >.

2, relevant interference

Relevant interference signal comprises Convolution Noise, Doppler's noise and intensively copies interference.

Convolution Noise interference model is realized the Convolution Jamming Technique > > of linear FM radar with reference to the < < that is published in < < electronics and information journal > > in June, 2007.Traditional noise interferences due to radar signal processor mismatch, cause most of interfering energy by matched filter filtering, interference effect is reduced.Convolution Noise is by baseband noise and impulse radar signal convolution, obtains Convolution Noise signal, then up-conversion output.The fundamental purpose of doing is like this that noise decrease undesired signal is passed through the energy loss after matched filter, and then hides the echoed signal after pulse compression, affects subsequent detection.Convolution Noise can make full use of interfering energy, under lower power input, can produce better interference effect to chirp-pulse compression radar.

The Doppler noise of the < < that the model reference of Doppler's noise is published in < < electronic information countermeasure techniques > > in April, 2010 based on narrow band noise phase modulation realized the interference analysis > > of PD radar.When realizing, Doppler's noise signal bandwidth is 5MHz to the maximum, and 250MHz is relatively little for the relative plateform system clock of bandwidth, after producing specific bandwidth white Gaussian noise, in order to reach the sampling rate of 250MHz, need to carry out interpolation filter processing to band limited white noise.Because interpolation multiple is higher, in order to save hardware logic resource, with the integral comb filter of cascade, realize here.

The radar active of Doppler's noise model reference master thesis < < of University of Electronic Science and Technology in 2010 based on FPGA disturbs generating technique research > > to realize.Decoy is intensive copy disturb the mode that adopts delay stack to target at distance coverage goal echo upwards, undesired signal upwards can obtain processing gain in distance, covers real goal, reaches wire interference effect.The intensive mode copying realizes, and uses time delay module, sense data after delay a period of time, and just distance is upper different from former target for the target copying.In single RRI, intensive copy pulse number is 100, and is uniformly distributed in distance, and Doppler is identical, and amplitude is identical.

3, duplicity is disturbed

Duplicity interference model is realized with reference to the < < SAR active cheating formula interference model research > > that is published in < < modern defense technology > > in August, 2009.Duplicity is disturbed main according to the producing method of SAR target echo, generate angel echoes, after receiving SAR radar emission signal, directly decoy is replied and is transmitted to radar, making to be mixed with in SAR radar return signal must decoy information, after general SAR imaging processing, form SAR decoy or image.

For point target, disturb, in implementation procedure, each target in dot matrix can be regarded an independently SAR point target as, each target is carried out independently phase-modulation, target travel is processed according to uniformly accelrated rectilinear motion, by FPGA, complete the interpolation arithmetic of target trajectory, the final weighting output of a plurality of independent point targets is obtained to the simulation of dot matrix target echo signal.

For Area Objects, disturb, consider that SAR Area Objects emulation scattering point number is more, it is unpractical according to common point target implementation, for FPGA, realizing, therefore the realization of Area Objects is required to set in advance current PRI(pulse recurrence interval) and PRI remain unchanged, obtain current analogue system echo transport function, system real-time playback upgrades echo transport function, then by obtaining base band target echo signal with radar baseband signal convolution.In real time the required radar baseband signal of convolution, by gathering radar intermediate frequency signal, is then carried out Digital Down Convert and FFT(Fast Fourier Transform (FFT)) process and obtain.

4, land clutter disturbs

Land clutter interference model is realized with reference to the Clutter simulation model > > being published in June, 2003 in the < < radar signal simulator of < < aerospace electron antagonism > >.Clutter refers to and receives the echo component causing due to volume scattering or surface scattering comprising in signal in radar.For the simulation of noise jamming, the mode that conventionally adopts base band echoed signal and Clutter Model data to carry out real-time convolution produces.According to model, produce base band clutter data, under the triggering of detection pulse, carry out convolution with transmitting of receiving.For the simulation modelling of clutter, the probability density function that can change by Radar Cross Section and the scattered power of clutter is portrayed.Clutter can be divided into according to amplitude statistics model: Rayleigh, Weibull, logarithm-normal state, K, can be divided into according to power spectrum: Gaussian spectrum, Cauchy's spectrum, cube spectrum.

5, chaff disturbs

Chaff interference model is realized with reference to a kind of modeling and simulation method > > that is published in the < < Chaff Cloud Echo of < < modern radar > > in August, 2006.In order to produce more easily chaff undesired signal, need further to simplify the echo model of chaff signal, utilize simple means to reappear characteristic as chaff echo signal all, comprise apart from time delay, distance diffusion, echo power fluctuating, Doppler shift, Doppler spread, form etc. transmits.This realization thinks that chaff cloud is comprised of a plurality of small cubes, and the movement velocity of each small cubes is not consistent, the fluctuating of a speed will be had, think this fluctuating Normal Distribution here, so just can obtain the Doppler shift that the velocity fluctuation of each small cubes causes, can produce with that this echo of little cube, finally all echoes of little cube are added to the echoed signal that just obtains chaff cloud integral body.

When reality is used, the analogue means that can adopt many playscript with stage directions inventions to propose, coordinates by networking, the space electromagnetic interference signal of simulation different directions, all kinds stack.

The content not being described in detail in instructions of the present invention belongs to those skilled in the art's known technology.

Claims (3)

1. a multi-functional SAR complex electromagnetic environment analogue means, is characterized in that: comprises antenna and microwave subsystem, the generation of base band interfere information and modulating unit, the real-time figure collecting unit of SAR, controls and show and model unit, wherein:

Antenna and microwave subsystem: comprise electromagnetic horn, radio-frequency cable, AGC unit, multistage down-converter unit, frequently comprehensive unit, multistage up-conversion unit, power adjustment unit; SAR radar emission signal receives by electromagnetic horn space or delivers to AGC unit by radio-frequency cable, AGC unit carries out delivering to multistage down-converter unit after power adjustment to SAR radar emission signal, and the SAR radar emission signal of multistage down-converter unit after to power adjustment carries out obtaining if radar signal and export to base band interfere information producing and modulating unit after two-stage down coversion; Multistage up-conversion unit carries out delivering to power adjustment unit after two-stage up-conversion to the middle frequency interference signal that base band interfere information produces and modulating unit generates, the middle frequency interference signal of power adjustment unit after to up-conversion carries out obtaining Radio Frequency Interfere after power adjustment, and Radio Frequency Interfere is delivered to SAR radar by electromagnetic horn space radiation or by radio-frequency cable; Frequently combining unit provides work required frequency signal for multistage up-conversion unit and multistage down-converter unit, for base band interfere information produces and modulating unit provides work clock;

Base band interfere information produces and modulating unit: comprise instantaneous frequency measurement unit, the real-time computing unit of interfere information, the real-time modulating unit of interfere information; The real-time computing unit of interfere information shows according to controlling the interference parameter transmitting with model unit, produces the baseband modulation information of corresponding interference type; Instantaneous frequency measurement unit obtains the frequency of if radar signal by the method for digital Frequency Measuring; The real-time modulating unit of interfere information produces required middle frequency interference signal by baseband modulation information according to the frequency of if radar signal and if radar signal and delivers to the generation of base band interfere information and modulating unit after ovennodulation;

The real-time figure collecting unit of SAR: receive SAR realtime graphic and deliver to and control demonstration and model unit by LVDS interface;

Control and show and model unit: comprise interface control and display unit, interference model unit; Compacting interference model, cheating interference model, relevant interference model, chaff interference model, noise jamming model have been stored in interference model unit, call corresponding interference model produce corresponding interference parameter and deliver to the real-time computing unit of interfere information according to the disturbed condition of outside input; According to the disturbed condition of outside input, the power of power adjustment unit is controlled; Image and real image that SAR radar is generated under disturbed condition are compared, and obtain SAR interference effect; The running status of whole analogue means is monitored and reference record.

2. a kind of multi-functional SAR complex electromagnetic environment analogue means according to claim 1, is characterized in that: described multistage down-converter unit comprises two frequency mixer, automatic gain control device, low-pass filter; 12～18GHz radiofrequency signal of SAR radar emission is carried out first order down coversion with the local oscillation signal of frequency range 12～16GHz that frequently comprehensive unit provides by the first frequency mixer, obtains 2GHz the first intermediate-freuqncy signal; The first intermediate-freuqncy signal is after automatic gain control device carries out automatic gain control, second level down coversion is carried out in the local oscillation signal mixing of the 2.5GHz providing by the second frequency mixer and frequently comprehensive unit, and the signal after the down coversion of the second level obtains the if radar signal of 500 ± 250MHz after low-pass filter.

3. a kind of multi-functional SAR complex electromagnetic environment analogue means according to claim 1, is characterized in that: described multistage up-conversion unit comprises two frequency mixer, bandpass filter, switch filter group, two amplifiers and attenuator, 2.5GHz local oscillation signal mixing in three-mixer that middle frequency interference signal and frequently comprehensive unit provide obtains the signal of 2GHz frequency, the signal of 2GHz frequency is delivered to the 4th frequency mixer after amplifying by band-pass filter and the first amplifier, in the 4th frequency mixer, the signal of 2GHz centre frequency obtains with 12～16GHz local oscillation signal mixing that frequently comprehensive unit provides the signal that centre frequency is 12～18GHz, signal bandwidth is the M signal of 500MHz, M signal is met 12～18GHz signal of purity requirement after by the corresponding frequency range of switch filter group filtering, 12～18GHz the signal that meets purity requirement is decayed and is carried out obtaining required Radio Frequency Interfere after power amplification with the second amplifier through programmable attenuator successively.

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