Evoked Potential Latency Delay Estimation by Using Covariation Correlation Approach

Evoked potential (EP) signals have been widely used to quantify neurological system properties. Delay in EP signals latency may be linked to neurological injuries. For abnormal cases where noises in EP signals usually appear impulsive, a novel robust approach, covariation correlation algorithm, is proposed to estimate EP latency delay based on fractional lower order statistics (FLOS) under alpha-stable distribution noise. Firstly, the auto-covariation of reference signal and cross-covariation between reference and detected signals are computed. Secondly, correlation between these two covariations series is calculated. Finally, the estimation value of EP latency delay is obtained from location of this correlation peak Simulation studies show that the estimation precise of this novel algorithm is higher than that of correlation or covariation algorithms especially under lower mixed signal noise ratio (MSNR).