一种改进的差分前向频率估计

An improved differential feed-forward frequency estimator

考察基于模π/4算法的差分前向频率估计在8PSK载波恢复中的应用,在高斯复噪声的影响下,求模运算引入部分相位模糊点,降低了该算法的估计精度和有效估计范围。提出一种反馈校正的频率估计方案并进行性能仿真,结果表明该方案有效纠正了模π/4运算引入的相位模糊,提高了估计精度,拓宽了有效估计范围。给出了改进算法的FPGA实现框图。

This paper concentrates on the application of a mod π/4 algorithm based differential feed-forward frequency estimate （DFFE） in the 8PSK carrier recovering system. With the influence of Gaussian complex noise, modulo operation induces some fuzzy phase values, which reduces the precision and the range of the estimate algorithm. An improved frequency estimating scheme is proposed by revising the mod π/4 operation by feedback, and the simulations were carried out. Simulation result shows that the proposed scheme effectively corrects the wrong phase values, improving the estimate precise and extending the estimate range. And the algorithm is implemented in FPGA.