Based On Virtual Instrument Technology And Downs Of The Radar Echo Simulation And Detection Probability Test

Radar fuse, which considers terrain targets such as desert, residential area and industrial area, irradiates a large area which can be regarded as components of many scattering cells. Each cell can scatter radio wave so that total echo received by fuse is sum of each scattering echo vector. Due to move of radar fuse in respect to ground, scattering wave has random amplitude and phase so that their sum of vectors namely echo is fluctuating. Echo fluctuation has influence on fuse's detection probability. Comparing to non-fluctuating echo, fluctuating echo needs high Signal Noise Ratio in case of high detection probability. Therefore, it's very important to study influence of fluctuating echo on detection probability. However, existing special radar echo simulator can't simulate fluctuating echo. So, it is very exigent and necessary to study a method to simulate fluctuating echo and test detection probability of a real radar fuse under condition of such echo.A new method, which uses Vector Signal Generator E8267D to simulate fluctuating echo of Swerling I and II models and non-fluctuating echo and to test radar fuse's detection probability by virtual instrument technology, is put forward in the paper. Aimed at a real fuse, requirement of signal generator for fluctuating echo simulation is analyzed. Some problems, like match and time synchronization between fuse and testing instruments, are solved. Characteristic of Swerling I and II models are analyzed, method about simulation of fluctuating echo and flow of detection probability test are studied, and communication of virtual instrument software LabVIEW with MATLAB and Excel is settled. Therefore, an experimental platform containing fluctuating echo simulation, detection probability test and results storage is set up. Based on it, relation curve between detection probability and echo signal power under condition of non-coherent integrated pulse number and relation curve between non-coherent integrated pulse number and echo power under condition of determinate detection probability are given in the paper. Comparison results of both show that detection probability testing datum are in accord with theoretic datum so that availability and correctness of the method are validated.The finish of the subject has a comparatively important practical meaning.(1) The fluctuating echo simulation can reduce the difference between test conditions in laboratory and actual work environment of radar fuse and reduce manpower, material resources and financial resources used in outfield and the experiment has high degree of recurrence. (2) The introduction of existing general instruments to simulate fluctuating echo can reduce time and expense for the development of special radar echo simulator.(3) Detection probability under condition of fluctuating echo not only can provide basis for fuse's detection performance evaluation and design optimization, but also help designers understand fuse system roundly.(4) The introduction of virtual instrument test method to measure detection probability can overcome disadvantages brought by traditional test method, such as fussy test task, low data precision and inconvenience of data record and storage.