改进的低信噪比短序列快速频率估计算法  

Improved algorithm for fast frequency estimation with short sequences at low SNR

作　　者：阎振华[1] 黄建国[1] 韩晶[1] 

机构地区：[1]西北工业大学航海学院,陕西西安710072

出　　处：《系统工程与电子技术》2009年第8期1990-1992,共3页Systems Engineering and Electronics

摘　　要：快速频率估计算法的研究对工程实现具有重要的意义。以低信噪比下水下声信号快速频率估计为背景,建立了数学模型,提出了一种基于短序列快速频率估计的改进算法。该算法是基于对三点自相关算法的改进,在没有增加运算复杂度的基础上提高了频率估计精度。仿真实验结果表明,该算法与三点自相关算法相比,其均方根误差(root mean square error,RMSE)更接近于克拉美-罗下限(Cramer-Rao bound,CRB),在低SNR情况下,比三点自相关算法低5 dB左右,并且当SNR提高到10 dB左右时,其RMSE能够接近CRB。It is significant for engineering application to study the fast frequency estimation algorithm. Thus, by establishing the mathematical models, an improved fast frequency estimation algorithm with short sequences is proposed for underwater acoustic signal detection at low signal to-noise ratio （SNR）. It is based on the three-point self-correlation algorithm, but provides more precision than the latter with no cost of increase＇in computational complexity. The simulation results show that the root mean square error （RMSE） performance of the proposed algorithm is closer to Cramer-Rao bound （CRB）, which outperforms its counterpart by 5 dB at low SNR and reaches the CRB at the SNR up to 10 dB.

关 键 词：参数估计 快速频率估计 改进算法 短序列 低信噪比 克拉美-罗下限 

分 类 号：TN911.7[电子电信—通信与信息系统]