Patent ID: 6512944
Filing Date: 2003-01-28
Classification: A61B,Y10S

Abstract:
Signal processing apparatus comprising:(a) a signal source; (b) a signal output point; (c) a plurality of concatenated digital filter stages connected between the signal source and the signal output point, each of said filter stages including (i) a time delay buffer having an input for receiving digital data representing sampled values of a noisy analog signal at a predetermined sampling rate and for at least temporarily storing said sampled values for predetermined time intervals, said time delay buffer providing an output; (ii) means for deriving from the output of the time delay buffer an average-over-time noise signal component falling within a predetermined frequency band, and (iii) means for selectively subtracting the average-over-time noise signal component from the output of the time delay buffer to remove the average-over-time noise signal component from the sampled values stored in the time delay buffer.