The Study Of Shipboarne Radar’s Anti-interference

As the electronic circumstance is becoming complex, the study of ECCM(Electronic counter-countermearsures) is becoming much more important, and it’s one of the most important subject in EW. So it’s of great significant in national defense. In this dissertation, a study is performed about ECCM methods based on the circumstance in the world.Firstly, all the parameters of jammer and the way it obstructed are analyzed. Four kinds of theory are composed, including responder interference, forwarding interference, composite dexterous interference and distributed interference. Based on the theory above, some precepts are composed to solve the problems of interference.Secondly, based on the comparison and analysis of the jammer, some principles of intercepting low probability of intercept signal:WVD time-frequency analysis, smooth cycle analysis, higher order statistics analysis and so on. The advantages of smooth cycle analysis are analyzed.Thirdly, the signals of ECCM are put forward and compared. Some methods of keying are proposed, such as:LFM signal, nonlinear frequency signal, PSK, FSK, and complex keying.Fourthly, four kinds of interference suppression algorithm are put forward, including:side lobe continuous wave interference suppression, side lobe pulse interference suppression, main lobe interference suppression and forwarded the false target, main lobe continuous wave interference suppression. There are four ways to realize main lobe interference suppression and forwarded the false target, including: based on pulse edge detection of false target interference suppression, based on the dual separation of false target interference suppression, based on subspace projection airspace-polarization domain of radar active decoy interference suppression and based on fractional domain subspace projection of radar active decoy interference suppression.Lastly, all the thesis above are simulated. The experiment made lastly confirm that the effectiveness and of the theory.