Study On The Adaptability Of Electronic Interference In FM Doppler Pitch System

FM Doppler system has been widely used in the field of short range detection. With the increasing complexity of electromagnetic environment and the development of the eccm techniques, how to analyze and evaluate the jamming effectiveness of the system accurately and quantificationally has become an important issue. In this paper, triangle wave FM Doppler system is taken as an example. The anti-jamming ability is studied combined with theoretical analysis, simulation and experimental verification.According to the providing principle block diagrams of FM Doppler system, the working principle is analyzed, and signal forms of the signal processing are deduced. The Simulink simulation model of moving target detection is constructed. Second, the regular interference signals of periodic waveform amplitude modulation jamming, periodic waveform amplitude modulation sweeping frequency jamming and periodic waveform frequency modulation jamming are studied and signal forms of the signal processing are deduced. Major factors influencing the deception jamming effectiveness are discussed based on the shape and amplitude of the envelope. The noise signal of noise AM jamming and noise FM jamming are studied and signal power of the signal processing is deduced. Major factors influencing the suppression jamming effectiveness are discussed based on the signal to jamming ratio gain. The interference signal simulation experiment platform based on Simulink is constructed to verify the theoretical results.Finally, the actual FM Doppler interference experiment platform is built based on the radio frequency signal processor and a lot of test data is analysed. It is found that FM Doppler system has strong anti-jamming ability for most of the interference signal, but lack of interference resistance for the frequency sweep signal. So the FM Doppler circuit design and signal processing method can be improved from this point.