摘要
通过分析加ssinc窗的循环周期图在谱频率方向和循环频率方向的偏差,分析了TA循环谱估计是无偏估计。然后,根据STFT方法,推导了使方差得以减小的平均循环周期图的计算方法,同时分析了加ssinc窗的平均循环谱估计能使方差得到最佳地减少,并采用平均的TA循环谱估计方法,估计了具有不同循环频率的两个循环平稳信号和的循环谱,所得的循环谱能在循环频率方向将各循环平稳信号准确地分离开,并在各循环频率处的谱频率方向准确得到各自的功率谱。
The bias of cyclic periodogram with ssinc window is analyzed in both spectrum frequency direction and cycle frequency direction, and that the TA cyclic spectrum estimation is unbiased is proved. The average method of cyclic periodogram is also gotten in terms of STFT. Meanwhile, this paper indicates that the variance can be optimistically reduced through the cyclic spectrum estimation with ssinc window. The estimations of cyclic spectrum of the signal which is the sum of two cyclostationary signals are then done by the way of averaged TA cyclic spectrum estimation, and the result shows us the spectrum in the spectrum frequency direction is exactly presented at each cycle frequency.
出处
《微电子学与计算机》
CSCD
北大核心
2007年第7期76-79,共4页
Microelectronics & Computer
关键词
循环平稳
循环谱
循环周期图
时间重叠
cyclostationary
cyclic spectra
cyclic periodogram
time aliasing
