Research On A FH Synthesizer In VHF Radio

The technique of frequency synthesis is the hard core of the frequency-hopped communication and it is the primary technique among the methods of realizing high stability carrier wave and frequency changing. The capability of the frequency synthesizer determines the whole capability of the FH system.This paper bases on frequency-hopped and frequency synthesis theories, and through demonstrating three schemes of frequency synthesis, the paper selects one of these schemes that uses DDS spiriting up PLL and improves on the method according to the practical target and synchronously, the paper analysis the capability of the output signal and the conversion time of the frequency. Based on these theories and experiences, the paper researched and developed hardware circuit and software modules. Hardware circuit provides the interface of the input data and the programming method cooperates with hardware accomplishes the FH frequency synthesizer. At last, the whole paper is summarized and provides theories and experiences for more effective amelioration.