引用本文: | 肖志斌,唐小妹,王飞雪.基于DFT系数极值的单频信号频率的高精度迭代估计方法[J].国防科技大学学报,2013,35(2):99-103.[点击复制] |
XIAO ZhiBin,TANG XiaoMei,WANG FeiXue.High accuracy iterative frequency estimating algorithm based on the extremum of the DFT coefficients[J].Journal of National University of Defense Technology,2013,35(2):99-103[点击复制] |
|
|
|
本文已被:浏览 8308次 下载 7331次 |
基于DFT系数极值的单频信号频率的高精度迭代估计方法 |
肖志斌, 唐小妹, 王飞雪 |
(国防科技大学 电子科学与工程学院,湖南 长沙 410073)
|
摘要: |
提出了一种基于DFT系数极值的单频信号频率的高精度迭代估计方法,该方法根据DFT谱线使用截弦法解算DFT系数极值所在谱线的位置,进而估计单频信号频率。在估计过程中,直接对DFT幅度最大的谱线进行小数频移以获得新的谱线,从而减少频率采样间隔提高估计精度;同时通过迭代估计消除频率依赖性,提高估计性能。仿真结果表明该方法的频率估计精度在任意频率处均接近于克拉美罗下限,其运算量为Nlog2N+4N次复乘法运算,仅比传统的基于DFT插值的估计算法增加4N次复乘法运算,其中N为DFT运算时所采用的数据点数。 |
关键词: DFT插值 截弦法 迭代估计 克拉美罗下限 |
DOI: |
投稿日期:2012-06-07 |
基金项目:中国卫星导航年会青年优秀论文资助课题(CSNC2011-QY-06) |
|
High accuracy iterative frequency estimating algorithm based on the extremum of the DFT coefficients |
XIAO ZhiBin, TANG XiaoMei, WANG FeiXue |
(College of Electronic Science and Engineering, National University of Defense Technology, Changsha 410073, China)
|
Abstract: |
At present, frequency estimation algorithm based on DFT interpolation is widely
used because of it’s high operation efficiency, but the estimating accuracy is dependent on the signal
frequency, and for specific frequency, the estimation performance is bad. To solve this problem, a high
accuracy frequency estimation algorithm with lower calculating complexity is proposed. In this algorithm, the
signal frequency was estimated by Secant Method based on the DFT samples, and decimal fraction frequency of
peak magnitude DFT sample was estimated to generate new DFT samples, thus reducing the DFT sample interval
with little calculating burden, then improving the estimating accuracy. In addition, through removing the
frequency reliant characteristics of estimation which exist in traditional frequency estimator based on the
DFT interpolation, this algorithm increased the iterative estimation. To analyze the performance of the
algorithm, a simulation was fulfilled. The simulation results show that the single frequency estimator without
iterative estimation has asymptotic estimating variance less than 1.2 times the CRLB, which is better than the
traditional frequency estimator based on the DFT interpolation, with calculation labor of N log2N+2N complex
multiplications, and the iterative frequency estimator has estimating variance about CRLB for all signal
frequency calculation labor of N log2N+2N complex multiplications, and N is the number of the DFT samples. |
Keywords: DFT interpolation Secant-Method iterative estimation CRLB |
|
|
|
|
|