The Research Of Spread Spectrum-Adaptive Antennas Anti-interference Communication Technology

There are strong man-made interferences in the military communication, so it's not efficient to eliminate them by only one method. The main ways of anti-interferences are adaptive array, spread spectrum and processing in frequency domain. The thesis introduces a method of adding anti-interferences function to SSB radio by combining adaptive array and spread spectrum technology.The thesis is outlined as follows.In chapter 1 the overall works and basic theories concerned are introduced.In chapter 2 we introduce the A/D method, include the band-pass sampling theory and the how to decide the sampling position, sampling accuracy and sampling rate.In chapter 3 the DDC(Digital Down Converter) and DUC(Digital Up Converter) designing is presented by giving parameters of AD6635 and AD9857 separately.In chapter 4 an algorithm of LMS for adaptive beam forming is presented.In chapter 5 we introduce the FPGA technology and the realization of LMS algorithm in FPGA.In chapter 6 we summarize all the works of the thesis.