Improved adaptive noise cancellation in the presence of signal leakage on the noise reference channel

Abstract

This paper describes an adaptive noise cancelling structure suitable for situations where the noise reference transducer is closely spaced relative to the primary transducer. The structure is based on two LMS delay line cancellers with cross-coupled feedback. This structure is shown, under certain circumstances, to cancel noise with low signal distortion when the transmission paths between primary and secondary sensors have low attenuation and the primary signal is continuous. An enhanced performance would be achieved when the primary signal is intermittent and a signal energy detector is used.