Hi Viginesh,
Spectral monitoring of EEG signals is pretty straightforward. Normally, the time domain signal is broken into short epochs of a few seconds and an FFT is performed on that data array. The data from the FFT is binned into frequency ranges according to standard EEG definitions: Delta, (0-4Hz), Theta (4-8Hz), alpha (8-12Hz) , etc. The Peak power value in that frequency range and/or the cumulative power (total power in that bin) is reported. Then the next segment of EEG data is processed and this continues either in real-time or on a prerecorded file of EEG. This process is duplicated for each channel of data corresponding to different locations on the brain.
Another common EEG processing task is looking for abnormal spike activity that is associated with epilepsy and is sometimes the precursor to seizures. Various methods are employed, including template matching, wavelets processing, and even neural net processing.
Can you tell us more about the actual processing that you need to do on your EEG data?
Steve
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