CONCLUSIONS &
FURTHER
STUDY
|
Our implementation sucessfully achieved system idetification and noise
cancellation. Specifically, time varying noise was reduced. The effects of
varying different paramters in the algorithm were also observed. It was
found that the stepsize mu affects the rate of convergence, a larger mu
leads to faster convergence, but too large a mu can produce divergence. The
order of the filter used afffects the distortion of the desired
signal. Because of the adaptive filter updates its coefficients to minimize
the error between the primary and reference siganls, we get poor
performance if the desired signal is similar to the reference signal. This
method of noise cancellation is most useful when the reference noise that
we have access to is large or delayed relative to the noise that is
actually in the primary signal.
The next area to explore would be to implement different algorithms for
updating filter coefficients, for example the Normed Least Mean Squares
algorithm was briefly experimented with. The system gave an acceptable
output for white noise reduction, but its performance could be greatly
improved. This noise was much more difficult to eliminate since there
exists little correlation between the reference nosie and the noise in
primary, given that they are both completely random. Finally, we can
customize our system for various real world applications.