关键词: 定时同步, 插值滤波器, 定时误差检测器, S-曲线, Gardner算法, QPSK调制

Abstract: Aiming at the problem that the existing timing synchronization algorithm needs a long time acquisition, poor stability and high error rate, an improved Gardner synchronization algorithm is proposed. On the analysis of different interpolation filter, piecewise parabolic interpolation filter is used in synchronization structure. For QPSK signal, open-loop and closed-loop analysis is carried out respectively. Simulation result shows that compared with previous algorithms, the proposed synchronization method has 0.005 s shorter acquisition and then the mean square error is reduced. Moreover, the bit error rate is significantly reduced while signal to noise ratio is greater than 8 dB.

Key words: timing synchronization, interpolation filter, timing-error detector, S-curve, Gardner algorithm, QPSK modulation