QPSK数字化解调中载波同步技术研究

Carrier synchronization technology on QPSK signal digital demodulation

分析了判决辅助载波同步和非判决辅助载波同步的基本原理,研究了基于信号相位的载波频偏估计算法和基于信号自相关函数载波频偏估计算法,提出了基于恒包络零自相关(CAZAC)序列为前导的载波同步算法,并对基于CAZAC序列的载波恢复算法进行了分析和计算机仿真,结果表明该算法性能优良且实现简单。

In this paper, we present the principle of directed decision carrier synchronization and non-directed decision carrier synchronization, discuss the algorithm of carrier frequency deviation estimation based on the phase of signal and the autocorrelation function of signal and propose an algorithm with the preamble of constant amplitude zero autocorrelation （CAZAC） sequence. The performance of the algorithm based on CAZAC preamble sequence is demonstrated by means of simulation, the results show that the estimation can be usefully exploited.