Analysis, Design and Implementation of FSK Modulate Systems

Abstract

The hybrid signals are the combined signals with multi-modulation mode. With multi-modulation, the disadvantages of single-modulation (such as FSK, PSK and PPM) can be eliminated. By taking the advantages of different modulations, the performance of range resolving, Doppler resolving and low probability of intercept (LPI) of the signal can be improved. FSK/PSK radar signal is the signal with both FSK and PSK modulation at one time. It is with large Bandwidth Time product (BT), thumbtack-like ambiguity function and well ability of Anti-EMI. The FSK/PSK signals of which the frequency-hopping and bi-phase sequences were randomly chosen often had high side lobe level. With the simulation and analysis using MATLAB, the method of FSK modulation is made analysis. As a result, the automatic modulation recognition is one of the necessary functions.