Research On Broadband Digital Channel Active Jamming Technology

Channelization technology has important and extensive applications in voice,image,communication,software radio,radar receiver and many other national economic and military fields.Aiming at the requirement of high fidelity,high flexibility and miniaturization of high fidelity active jamming system,digital channelized technology is introduced into jammer.Based on the analysis of the existing DFT filter banks,finally choice 2 over-sampling DFT filter banks as the active jammer channel division and channel comprehensive realization structure,and deduced the poly-phase filter banks efficient implementation structure.The design of the prototype filter is the key problem for Modulated filter banks’ application.In the analysis of filter effect on reconstruction error,this paper presents an efficient filter design algorithm,can design arbitrarily long length filter.Finally,the receiving and transmitting model of channelized active jammer is successfully built on the Vivado software platform of Xilinx.The results of this paper will provide theoretical and technical support for the design and development of wideband channelized active jammer.The work carried out and research results are as follows:The first chapter is the introduction,describes the background and significance of developing broadband digital channelized jamming technology research,summaries the development status of wideband radar active jamming technology and semiconductor devices,finally introduces the main research contents and work arrangements.In Chapter 2,the basic theoretical knowledge of broadband digital channel jammer are introduced.Firstly,the structure model of wideband channelized active jamming is introduced;secondly,the time domain and frequency domain relations of the extractor and interpolator as well as the polyphase decomposition structure of decimation filtering and interpolation filtering are introduced;then,introduces the basic structure of the filter bank and the three error sources of the filter bank,and analysis the reconstruction performance of the polyphase DFT filter bank and the MDFT filter bank;finally,three interference patterns and corresponding mathematical expressions of one-dimensional and two-dimensional jamming effects are introduced,and the modulation signal generation method of subchannels is given.In Chapter 3,mainly studies the channelized structure design based on over 2 sampling DFT filter banks.Firstly,an efficient hardware implementation structure of over 2 sampling DFT filter banks is derived,which provides a reference for engineering implementation;then,the steps of frequency domain filter design algorithm for particle swarm optimization(PSO)hybrid optimization algorithm based on oscillating weight factor are described in detail;then,the simulation results show that the proposed algorithm has a significant improvement in the reconstruction accuracy and peak signal-to-noise ratio of the filter banks compared with the other three algorithms,and the algorithm can design any length of the filter,and is not sensitive to initial parameter values;then,based on the channelization structure of 8 channels,the reconstruction experiments of narrowband and wideband signals verify that the accuracy of the reconstructed signal based on the channelization structure of the 2-sampling DFT filter bank is much higher than that based on the DFT filter bank or based on critical sampling DFT filter bank;finally,the effectiveness of channelized interference modulation based on over 2 sampling DFT filter banks is verified by taking the convolution jamming pattern as an example.In Chapter 4,mainly studies the hardware realization of the signal processing sub-system of channelized jammer.Based on 32 channels,an implementation scheme of channelized reception and transmission structure based on 2-sampling DFT filter is given.Verilog programming is implemented in Vivado.The validity of this scheme is verified by comparing ISIM simulation results with MATLAB results.In Chapter 5,mainly summarizes the work and innovation of this paper,and points out the next research direction.