EVOKED POTENTIAL EXTRACTION BASED ON MULTI-CHANNEL TIME-FREQUENCY COHERENCE
诱发电位的多通道时频相干提取算法

The multi-channel time-frequency coherence algorithm is presented for extracting wideband signal from strong noises. The algorithm records signal with multi-channel, in which the useful signals in different channels will have higher coherence, while noises have lower coherence. According to this prop-erty the algorithm can separate the signals from noises. First, the recorded noisy signals were expanded in time-frequency domain with wavelet package, then the time-frequency distribution of useful signal was determined according to the coherence, finally the useful signal was reconstructed from the time-frequency distribution. The algorithm can extract wideband signal efficiently with only one iterate and without prior knowledge of the signal. Using this algorithm, extracting video evoked potential with single trial was realized successfully.