Introduction:The purpose
of this project was to implement a hardware multi-tap adaptive
noise canceller that could adaptively filter out the noise from
the contaminated source. The motivation originally came from the
paper titled "Adaptive Noise Cancelling: Principles and
Applications" which was published in 1975 by Widrow at Standford
University. Adaptive noise cancellers are based on the
least-mean-square algorithmn which was also proposed by Widrow
and his doctoral student Hoff at the time. Over the past four
decades, the LMS adaptive algorithm has served as a method that
is simple in implementation while highly efficient in providing
desirable and accurate results. It has found applications in a
variety of fields such as communications systems, robots,
machine tool manufacturing and automations. We thought it would
be interesting to implement a real time adaptive noise canceller
on the DE2 board. The experiment setup would be similar to a
noise cancelling headphone, which provides high audio quality in
noisy enviroment.