Research of hybrid DS/FH SS receiver based on Coded-Spread-Spectrum

摘要

A scenario and its experimental results of hybrid DS/FH SS (Spread Spectrum) receiver based code-spread-spectrum (CSS) is presented in the paper.CSS is an efficient spread spectrum technology.The transmission efficiency is improved when PN code rate isn't changed.It suits to the situations which are rigorous for the bandwidth.The hybrid DS/FH receiver presented by the paper uses TMS320C33 as the processor,and uses FPGA to implement correlator, digital down-convertor,PN code generator and matched filters. Frequency-synthesizer is implemented by DDSAD9854. Method which transmits pilot PN code captured by using serial/parallel technology to synchronize rapidly is brought forward. DPLL and SCAFCT(signed cross automatic frequency track) is used respectively to track code and carrier. The optimum noncoherent demodulation (Max SNR Output) which utilizes orthogonality of PN code can be the same with high dynamic environment.Finally,the figures including PN code synchronization and frame synchronization and demodulation are demonstrated. We can conclude that performance of the receiver is approving.