A New Neural Signal Collecting Circuit with High Signal to Noise Rate Performance

In this paper, a special kind of neural signal recording system including active microelectrode arrays is presented for the electroencephalogram-based brain computer interface (EEG-based BCI). As the electrical signal sensed by electrodes is extremely weak and is likely to be influenced by other radiation source in the nearby environment, many researches has been done to improve the signal-to-noise rate of neural signals in order to help neurophysiologists better understand neural action and the human being´s cognizance process. An integrated voltage-to-pulse generator circuit is proposed to improve performance, which get many advantages over other methods, such as adding preamplifier in the recording arrays. Since the electric field in the cerebral cortex can be described in Cartesian coordinate so the signals should be sensed tridimensionally. The simulation result will be discussed in the end of this paper to show the good measurement performance of this circuit.