Research On Jamming Technology Against STAP

Space-time Adaptive Processing(STAP)technology is widely used in airborne radar.It can filter clutter and suppress interference adaptively,and can effectively combat ground object clutter with two-dimensional coupling characteristics of Space and time.Reduceddimension(RD)STAP processing method can select part of data to calculate the adaptive weight,which improves the problem of full dimensional STAP in complex calculation and large demand of training sample.Based on the basic principle of STAP technology and RDSTAP technology,aiming at the weak points and limitations of this technology,this thesis studies the suppression jamming method,deceptive jamming method and isolated jamming method of STAP respectively.The research work of this thesis mainly includes the following three parts:The first part introduces the principle of the algorithm.The basic principles of STAP technology and RD-STAP technology are studied.Considering the actual environment of the airborne radar in the forward and side looking working state,the echo signal model of the airborne radar is established,the data model of STAP processor for echo signal processing is introduced,and the model structure of the optimal STAP processor and the basic principle of SMI algorithm are described.The second part is the study of interference methods.The jamming methods for STAP technology are studied,which can be divided into suppression jamming method,deceptive jamming method and isolated jamming method.Firstly,two kinds of suppression jamming signals,RF noise jamming signal and noise convolution jamming signal,are studied.The principle of the two kinds of jamming signals is introduced in detail,and the style of jamming signals is simulated and analyzed.Secondly,two kinds of deceiving jamming methods,intermittent sampling and forwarding jamming and non-uniform sampling and forwarding random jamming,are studied.Their principle of jamming is introduced,and the time domain waveform of the jamming signal is simulated and compared respectively,and the advantages of non-uniform sampling and forwarding random jamming are demonstrated.Finally,the jamming principle and jamming strategy of isolated jamming are studied.In the jamming scene of short-range jamming,false targets with Angle information deceiving and Doppler information deceiving are generated through random frequency shifting and other jamming methods.The third part is the interference simulation part.It is mainly about the interference effect of space time adaptive processing and dimension reduction space time adaptive processing by using the above method.Firstly,the jamming effect of RF noise interference is simulated,and the effective suppression ability of space-time adaptive processing technology on single RF noise interference is verified.Secondly,the interference effect of noise convolution jamming on space-time adaptive processing technology is simulated.Through the convolution of noise and signal,the suppression is formed on all Doppler frequencies of multiple range units,resulting in the radar cannot detect the local signal.Then,the jamming effects of intermittent sampling and random sampling on STAP technology are simulated.Both jamming can destroy the non-uniformity of training samples,resulting in the wrong weight calculation of adaptive processor and negative gain at the target position,so that the radar cannot detect the target position.Finally,the isolation of STAP technology interfere with the simulation experiment,by single airport scene and distributed scenarios with lead to interference signals into the target reconnaissance unit of distance,making the radar in space-time adaptive processing to interference signal suppression,thus caused by false information of target,simulation and analyses appeared slight lead error,show the effectiveness of isolation interference.