摘要
提出利用两个独立欠采样通道输出信号的互谱函数实现对欠采样信号的无模糊频率估计,为了提高测频精度,需要对信号真实频率与最大频域输出幅值对应量化频率的偏差进行较高精度的估算,采用全相位FFT与传统FFT联合校正频率偏差的方法,提出了全相位Rife综合算法,根据全相位FFT输出的最大谱线和次大谱线的比值决定采用全相位Rife算法或修正的细化Rife算法,仿真结果验证了该方法的有效性及高精度特性。
By using cross spectrum of signals from two independent channels,unambiguous frequency estimation for wideband signal with sub-Nyquist sampling is provided.To improve frequency measurement accuracy,high accuracy estimation of bias between real signal frequency and quantization frequency related to maximum amplitude of outputs in frequency domain is required.Based on joint all-phase FFT and traditional FFT,all-phase Rife synthesized algorithm composed of all-phase Rife algorithm and modified fined Rife algorithm is proposed in this paper.Which algorithm is employed is determined according to the amplitude ratio of maximum spectrum and sub-maximum spectrum of all-phase FFT outputs.Performance of effectiveness and high accuracy of the method are supported by simulation results.
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2010年第12期2771-2775,共5页
Journal of Astronautics
基金
国防预研基金资助(JY0100090201)
关键词
欠采样
互谱
频率估计
全相位Rife综合算法
Sub-Nyquist sampling
Cross spectrum
Frequency estimation
All-phase Rife synthesized algorithm
