Smsp And C&i Distance False Target Deception Jamming Recognition And Suppression Method Research

The Smeared Spectrum (SMSP) and Chopping and Interleaving (C&I) jamming, presented by M.J.Sparrow in2006to counter the pulse compression radar (PC radar), are two newly active range false target (RFT) jammings. They can produce a large number of range false targets to destory the detection function of radar, that is, radar cann’t distinguish the true target from the false targets and measure the information of the true target. Therefore, it has an important military significance to study how to identify and suppression the two jammings. First of all, the jamming characteristics and the mechanism of action of the two active RFTs are analyzed. Some new methods are proposed to identify the jammings and suppress the jammings based on jamming characteristics. The main contents of the disseration are as follows:(1) According to the working principle of the interference, the generation mechanism of SMSP jamming and C&I jamming are analysised, the mathematical model of them are given, the differences and similarities between the two jammings and the radar signal are studied in the time domain,frequency domain and the time-frequency joint domain, those work can provide study bases for jamming identification and suppression.(2) Thanks to the differences between the SMSP jamming and the radar target echo, the four methods are proposed to identify jamming, i.e. the instantaneous frequency of the jamming, the chirp rate of the jamming, the ambiguity function and the fractional Fourier tranform. The identify processes of the four methods are given in the disseration and the performance is evaluated by simulation, the advantages and disadvantages of the present methods are compared.(3) For SMSP jamming, after the type of the jamming is identified, the dissertation analyzes the characteristic variation of the received signal when the jamming enter the radar system. And then, combining the differences and the contacts between the jamming and the target echo, the disseration presents five suppression methods, such as the matched filtering, reconstruct SMSP jamming and so on. At last, the simulation results show a good effect. (4) For C&I jamming, combining the generation process of C&I jamming with its own characteristics, this disseration proposes a method to identify the type of the jamming, i.e.based on the ambiguity function. The identify process of the method is given in the disseration and the performance is evaluated by simulation, The simulation result shows that this method is effective.(5) After the type of the jamming is identified, combining the differences between the C&I jamming and the target echo, two methods are proposed to suppression C&I jamming, i.e.based on dechirp and reconstruct C&I jamming. The simulation results show that these methods have a good suppression effect.