时间延迟估计的循环相关法

依据离散时间序列的长度有限性,将其扩充为以序列长度为周期的周期序列,又依据周期序列的相关原理———循环相关,对信号进行时间延迟估计.由于循环相关的平稳特性,即使在较大延迟量存在的情况下,仍然能够达到准确的时延估计效果.模拟得到了不同强度的高斯噪声或不同时间延迟量下的广义相关能量图和循环相关能量图.模拟实验结果表明,在低信噪比或大延迟量的环境下,循环相关时延估计方法比广义相关时延估计方法具有明显的优势.

Circular correlation method of time delay estimation

Because the length of discrete time series is finite, the discrete series can be extended as periodic series. Therefore, the time delay estimation of a signal can be obtained based on the correlative principle of periodic series -- circular correlation. The accurate time delay estimation of a signal can be gained even if there is a great time delay because of the stationary performance of circular correlation. The generalized correlative energy diagrams and the circular correlative energy diagrams under the condition of different signal-noise ratios or different time delays are get by simulating. The comparison of the energy diagrams shows that, circular correlative time delay estimation method is better than generalized correlative time delay estimation method under the condition of low signal-noise ratio or great time delay.