Pseudo-random Code Keying Signal Processing Technology

With the changing environment of modern society,there is more and more request to Redio Fixed distance System. Modern Redio Fixed distance System must have to possess strong anti-jamming capability and the ability of accurate distance-determination, identify the target when in the condition of general environment. It is the direction by using different varieties of modulations in Redio Fixed distance System.In this thesis,through analyse FH system and PN Phase modulation system,PN frequency hopping system was discussed in detail. Then the process of modulation, demodulation and signal processing was simulated in Matlab. We can effectively weaken the impact of Doppler signal on PN correlation by selecting the appropriate parameters.We can resume delay PN code by using frequency discrimination.Based on this we also can recover Doppler message. The main hardware parts of signal processing was designed,and we also have result of simulate.,Especially frequency discrimination.The theoretical derivation and hardware simulate of Differential frequency discrimination have been given, signal generator was designed by using FPGA and DDS.