Shortwave Sfh / Qpsk Fh Modem

As strong anti-interfenece, high safety and long communication distance, Frequency-hopping of Short-wave communication play a important role in the military correspondence of technique.Though Frequency-hopping of Short-wave communication perform well when used in less noise conditions, the performance degrades rapidly when it used in real-world conditions. The focus of this research effort is to develop techniques which have more integrate, more flexible, more safe and autonomous intellectual property and some research results were obtained.A history review of frequency-hopping of short-wave communication theory was introduced in this paper at first. Based on the result come from the research with short-wave communication, hotspot and nodes of the research were list. Then the research on the direct digital frequency synthesizer(DDS) based on FPGA composes the design scheme of QPSK were proposed in the paper. The summarize of the paper was introduced in the end.