Software Radio-based General-purpose Digital Modulator

Along with the fast conversion of Communication technique from analog to numeral, and micro-electronics, numerical signal processing technique fast fierce development, the wireless correspondence technique got a huge development. because it has an equipments in brief and corresponds by letter to apart from far, Need not spread to establish circuit, mobile and vivid etc, Make it all occupy very and important position in the military and the public realm, The wireless correspondence system have very various of modulating way and looking for an address method, Realization's cutting over freely is the hot point problem on a wireless correspondence system and have to study in have another heavily, According to solve mutual communication of the system of communication. The software wireless technique emerges with the tide of the times, Through the development for several years, the software wireless technique has already got biggest applied in each profession, but the general numeral modulate technique become the point of research of a modern wireless correspondence, especially the frequency modulation correspond, have very high research value.This topic comes from the military radio station in preparing research item, after this paper analyse theories of the software wireless in detail, elaborated to the technique theories and way of modulating,In the further research mid-frequency numeral modulating and signal processing, combine to modulating way in common usely in the correspondence, tallied up a few kinds of arithmetic of mid-frequency numeric modulate, give out the MATLAB process in imitate reality, put forward general modulating model, calculator and simulation really, carrying out a concrete project on modulating circuit, carry out BPSK,QPSK,π/4-QPSK modulation, after testing ,all parameters meet the requirement.