Multi-CPFSK Demodulation Technology In Hopping Frequency Wireless Communication

Demodulation is the critical technology in communication system. It includes pre-modulation shaping, estimation and detection. When used in variant transmission channel the architecture and algorithm of modulation or demodulation should be best regard according to multi-level signal. It is the main research area that the architecture and algorithm of demodulation for MCPFSK adapted to frequency hopping signal.Early modulator/demodulator were constructed by analog circuits. And that brought noise, nonlinear distortion, power to impedance match and thermal stability which would cost lost. That is unhelpful to application. Then there comes digital communication which is adapted to all digital receiver with definitely receive architecture. So that we should face to estimation of best sampling time and synchronism parameter when signal translated in asynchronism mode. Anyway all digital receiver would be considered in this thesis.With the development of communication technology software radio application is increasingly approved. Its flexibility and reconstruction of software is a certain way to hardware and software compatibility for different communication systems and devices.Then we would aim at MCPFSK in the discussion.In the beginning digital communication theories and application development is produced. And the translation model, spread-spectrum technology especially some hopping spectrum radio station are introduced. Then all digital receiver construction and software radio technology are briefly declared.In the second part burst mode translation theories and software designing that is applied to software radio receiver would be explained. Then a recommendation for the symbol-timing track loop based on DPLL is reviewed, we propose an idea for loop filter design that used in software radio symbol timing track.In the third part modulation and demodulation for multi-level CPFSK is discussed particularly. We mainly aim at carrier frequency offset and symbol timing error estimation. And some simulation would be provided.At the last part we give expectation on software radio key technology and solution based on the discussion above.