An improved feed-forward timing estimation for GMSK signal

An improved nondata-aided (NDA) timing recovery algorithm for GMSK modulation is presented. The timing epoch is extracted from the period component of the received signal's square by means of averaging its auto-correlations. The auto-correlation with relatively lower SNR is ignored in the presented estimator and thus a better performance is achieved. A prefiltering scheme is also proposed to strengthen the period component of the received signal's square, which can make further improvement on the estimator. The simulation results are given to illustrate the performances of the improved algorithm.