Fqpsk Modulation System Analysis With All-digital Qpsk Demodulator

Because of the rapid development of communications engineering, the selection of modulation method is more important to increase the system capacity effectively in the case of wireless spectrum resource reduced largely. As the new generation of telemetry standard of the USA, FQPSK is the method which has high spectrum utility, great system capacity and improved power efficiency. The modulation and demodulation technique is studied based on software radio in this paper.First, the theory of FQPSK and it's preexistence IJF-OQPSK are introduced in the main section of my paper; Secondly, the modulation simulation of FQPSK with different ways is presented, and the main method is wavetable composing; thirdly, the realize of carrier synchronization and timing synchronization in the demodulation with the existing arithmetic are discussed and proved with computer simulation; lastly, the realization means of receiver is introduced and also the measure result analysis, relevant experiment summary and further work are mentioned in the paper.