Differential Demodulation of GMSK in Rayleigh fading Channels

A new demodulation scheeme for differentially encoded GMSK signal is introduced and described. In the proposed differential detection method, the signal is sampled at the center of the time slot, at which the effect of the intersymbol interference is relatively smaller than the edge of the time slot. The proposed differential detector takes this adbantate. The error rate performance of the differential detector has been numerically calculated in the fast fading encountered in the land mobile radio channels. A comparison of performance with the differential detector for MSK signal is given. Finally the possibility of improving performance employing nonredudant error correction is studied.