Adaptive discrete cosine transform for noise cancellation of vibrational signals

In this paper, the vibrational signal from a resistive strain gage is input into an adaptive cancelling system that uses a discrete cosine transform filter. The discrete cosine transform filter is a realization of a FIR filter as the cascade of an all-zero FIR filter with a bank of IIR digital resonators. Each bank has a single magnitude and a single phase. In the adaptive realization, the actual magnitude and phase are the parameters that are adapted with the LMS algorithm. Thus, in addition to cancelling the noise, the adaptive coefficients give an indication of the magnitude and phase at a full range of frequencies