Adaptive Digital Channelization Receiving Technology For Wideband Signals

The digital channelized receiver has a large working bandwidth,high intercept probability,and the ability to simultaneously process multiple time-domain overlapping signals.Thus,the digital channelized receiver has become a research hotspot in Electronic Reconnaissance and Electronic Warfare.According to the conventional digital channelized receiver,the sampling rate requirement for wideband signal receiving is high,and the signal cross-channel problem arises.In this paper,the adaptive digital channelization receiving technology of wideband signal is researched.In the case of the sparsely received signal in the frequency domain,this paper proposes a digital channelized receiving technology based on the Modulated Wideband Converter(MWC)system,which uses the sampling frame of the MWC system to achieve low-speed sampling of signals.Combined with the blind recovery algorithm,the channel analysis of the received signal is realized.The sampling framework of the MWC system utilizes the compression sensing principle to compress the signal during sampling,effectively reducing the sampling rate requirements of analog-to-digital converter(ADC).In this paper,the dynamic channelization idea of analysis and synthesis is used to propose a method of combining the MWC system-based digital channelization receiving technology with the synthesis filter bank structure.The support set information of the MWC system is used as the channel discrimination basis to realize the adaptive digital channelization receiving of wideband signal.Two adaptive digital channelization receiving structures are proposed for critical sampling conditions and over 2 sampling rate conditions.The main work and research contents of this paper are as follows:In the first chapter,the research background and significance of adaptive digital channelization receiving technology for wideband signals are expounded,and the development status of uniform digital channelized receivers and non-uniform digital channelized receivers is introduced.Finally,the main research contents of this paper and the structure of the article are introduced.The second chapter introduces the basic theory of digital channelized receiver and the general form of digital channelized receiver.It describes the principle and structure of the current mainstream digital channelized receiver based on polyphase DFT filter bank.The structure and characteristics of three representative non-uniform digital channelizers based on non-uniform filter banks,tree structure,and analysis and synthesis filter banks are described and illustrated.In the third chapter,for the frequency domain sparse signal model,the MWC system is introduced into the digital channelization receiving technology,and the digital channelized receiver based on MWC system is proposed.The low-speed sampling frame of MWC system and the blind sparse recovery algorithm are described.Under the specific parameter conditions of MWC system,the channelized output of the digital channelized receiver based on the MWC system can be realized,and the equivalent form of the traditional digital channelized receiver is described.In the fourth chapter,an adaptive digital channelization receiving technology based on critical sampling conditions is proposed.The support set of the MWC system is used as the discriminant basis for channel validity.The digital channelized receiver based on MWC system and the traditional synthesis filter bank is combined to perform the analysis and synthesis of the wideband signal,to achieve adaptive digital channelization receiving of the wideband signal.Aiming at the problem of aliasing distortion of synthesized signals under critical sampling conditions,an adaptive digital channelization receiving technology based on over 2 sampling rate conditions is proposed.The prototype filter of the filter bank is designed to meet the approximate perfect reconstruction conditions to achieve a more accurate reconstruction of the synthesized signal.The fifth chapter summarizes the main work contents of the this paper,and points out the next research direction.