Digital Receiving Techniques Of Wideband Signal Based On Polyphase Filters

Wide frequency domain and vast kinds of signals need to be processed are the main characters of modern signal processing. So receiver with perfect performances is required, such as wider frequency covering domain, real time signal processing , exact detecting for simultaneous arriving signals, and so on. With the developing of A/D, DSP, and FPGA techniques, prominent improvements have been taken in wideband signal digital receiving, which has being become a crucial research field in modern radar and communication systems.In this paper, basic theories of multirate sampling signal processing are presented at first. Then halfband filter based on interpolation, wideband and narrowband filters with sharp transiting bandwidth are presented. Then design principles and simulations for kinds of analysis filterbanks and synthesis filterbanks are given, which include maximally decimated filterbanks, factorization filterbanks, over-sampled filterbanks (OSFB). and so on. Based upon these, a novel wideband signal processing system is advanced, in which frequency cursory division is achieved by perfect reconstruct cosine-modulated filterbanks (PR-CMFB) firstly, and then numeral domain particular division is done using polyphase filterbanks. Then sub-channels that we are interested in could be perfectly sub-divided. It could be indicated from the simulation results that the system designed in this paper can satisfy the demand of real time and bandwidth for wideband signal processing, can solve the data transmitting bottle-neck between the former A/D and the back-end lower-converter, can also reduce the arithmetic complexity, can increase the operation speed. And the system is prone to be carried out on large scale integration (LSI).