The Modulation And Demodulation Of Baseband MSK Signal Based On DSP

As one technique of digital communications,MSK is very attractive in mobile radio environment.Along with the rapid development of VLSI technology and computer technology,DSP has been used widely in communications areas.In this paper, a baseband MSK transmitter and receiver based on DSP are studied and implemented.This paper introduces the development of digital communications and digital modulation.Analyses and simulates the modulation method of all-digital MSK signal based on Direct Digital Synthesis(DDS);Analyses and simulates the synchronization of the carrier and the bit synchronization algorithm based on the Discrete Fourier transform;According to the character of dsPIC30F platform,a method of the modulation and demodulation of baseband MSK signal is raised and used in the system of DSP,with experimental content as follow:1.The realization of the modulation of a baseband digital MSK signal.The modulation experiments are carried out by using the method of Direct Digital Synthesis based on the DSP.2.The realization of the demodulation of a baseband digital MSK signal includes digital to analog conversion,synchronization and demodulation.The significance of this thesis is that it uses the most advanced digital technology in the field of communication to realize the modulation and demodulation of MSK.It is based on DSP system to finish all kinds of functions and it is a soft way.The soft way used in this thesis is not the same as the traditional analog way.It is a fully digital method and has more flexibility.