Fuzzy two-stage carrier synchronization

This paper presents a novel two-stage carrier synchronization scheme. It provides both faster acquisition and better noise suppression than a conventional digital phase-locked loop (DPLL). The first stage produces the frequency estimate. The second stage is a new phase estimator, a DPLL with fuzzy adaptive bandwidth, to track frequency offset and phase. The simulation results show the improved performance. The main advantage of the proposed scheme over [7] is that it does not need optimization of fuzzy membership functions and a low computational cost of a DPLL is preserved.