Design Of Continuous Phase Modulation System Base On Hopping Communication

With the development of digital transmission technology, the traditional digital modulation has been unable to meet the application needs on the condition of the impact of the channel bandwidth limitations and the signal nonlinear transmission. Demand for a new digital modulation method is required to reduce the effect made by signal transmission in order to gain higher transfer rate.In this paper ,these studies, mainly involve the full spectrum savings and efficient use of the frequency bandwidth .Multimode modulation is a good method to increase the frequency efficiency and to maintain smaller frequency occupancy rate .This paper described the description of signal model, sort ,capability of cpm and frequency trait ,receiver form with different parameters ,the final summing up its signal characteristics and the feasibility of achieving .Secondly based on software radio, the paper gives the key technologies of continuous phase modulation system, including the sampling rate technology for the base-band and intermediate frequency conversion ,the key synchronous parameter estimation and achieving detection technology in demodulation, the interpolation technology for fractional sampling rate transformation and sampling Recovery ,the Maximum Likelihood Sequence Detection technology, the realization of programmers which comprise molding, modulation, demodulation, etc on software radio. Finally, following is the detailed information about the implementation of multi-mode cpm system on FPGA, the simulation results on the system, the hardware and software platform for software radio, debugging of hardware resources, the performance comparison between hardware final realization and simulation in the end.