Research And Implementation Of Adaptive Interference Cancellation Technology Based On FPGA

The integration of full duplex radar reconnaissance and jamming has always been the key technology and research hotspot in radar electronic countermeasure.Thanks to the increasing development of digital technology,the application of adaptive cancellation technology in the field of communication in the field of radar ECM is possible.With the help of adaptive self interference cancellation technology,the overall performance of radar jammer is greatly improved,and the miniaturization of radar jammer is possible,which increases the application scenario of jammer to airborne,missile borne miniaturized platform,increases the mobility of tactical radar,so as to better adapt to modern war.In this paper,an adaptive cancellation algorithm based on Gaussian white noise training is proposed.Using the broadband characteristics of Gaussian white noise,the filter coefficients suitable for the environment around the jammer are estimated,so as to solve the problem of CO frequency interference in the interference process of full duplex jammer,The radar jammer can easily deal with the switching of multiple detection signals of enemy radar.A set of jammer system working in both training mode and working mode is designed.It is verified by simulation,and finally implemented by FPGA.The main contents of this paper are as follows:Firstly,the two most basic algorithms of adaptive cancellation,LMS algorithm and RLS algorithm,are studied.The mathematical model of DLMS algorithm,which is derived from LMS algorithm,is deduced,and the simulation and performance comparison of the model are carried out.The influence of Gaussian white noise on adaptive cancellation algorithm is explored.According to the characteristics that Gaussian white noise can obtain filter coefficients with high applicability,training mode and working mode are proposed,and this theoretical model is popularized in practical application.Secondly,the hardware structure of full duplex radar jammer cancellation system is designed,including adaptive filtering module,delay estimation module and pipeline module.The overall structure design block diagram of radar jammer is given,and the interference module with deception mode and suppression mode is designed.The jamming modulation module is simulated by Vivado software platform,The simulation verification of three kinds of radar signal self-interference cancellation in deception and suppression mode is completed.Finally,the system is tested by using FPGA digital hardware platform and Chip Scope software platform to test the cancellation effect of the whole system in suppression mode and deception mode.Three typical radar signals are used to test the system,and the test results are analyzed by MATLAB software,The restoration degree of reconnaissance signal by the designed jammer cancellation module is given.