Design and realization of synchronization technique for FH-π/4-DQPSK communication system

In this paper, a series of methods and strategies of synchronization for frequency hopping-n/4-DQPSK (FH-n/4-DQPSK) communication system are proposed. By constructing the FH system and the format of frequency hop, the methods are divided into FH pattern synchronization, frame synchronization and symbol synchronization based on π/4-DQPSK modulation and demodulation. Then the strategies in capture mode and demodulation mode are described, which guarantee the normal operation of the receiver. Simulation results show that the synchronization methods and strategies can effectively acquire and track the FH signal which is confirmed by the realization on FPGA.