Feedforward synchronisation techniques for 16-QAM TDMA demodulators

A structure of a fully digital synchronisation unit for TDMA differentially encoded 16-QAM signal transmission, over cellular mobile radio channels, is considered. The feedforward non-decision-aided (NDA) synchronisation techniques used for symbol timing recovery and carrier recovery are described. A novel technique for carrier phase recovery is presented. The performance of the synchronisation parameters´ estimators at the receiver are evaluated by computer simulation in a slow Rayleigh fading environment. The statistical properties of the algorithms developed are evaluated in terms of the bias and variance of the estimated errors and are compared to the Cramer-Rao lower bound