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Unable to perform adaptive filtering in C6713

Started by Jayson Dmello March 9, 2007
Hi I have been trying to modify one of the exercise codes given in Dr Rulp
Chassaings Book 'Digital
Signal Processing with the C6713 and C6416 DSK," Wiley, 2005.

Ive attached the modified main file 'AdaptIDFIR1.c' as well as the original
project.The only difference being tht ive used external input (line or mic)
instead of random noise used in the original. and NLms algo is used instead
of LMS
However the output is always a loud noise.

Ive tried a very basic code
x=input_sample();
inp[0]=x;
for(i=0;i {
y+=inp[i]*w[i];
inp[i+1]=inp[i];
}.
.
.
.
**output_sample(x);
Even though i am not modifyin x the output gets noisy and at times the
output is indistinguishable
Any kind of advice would be really appreciated
The most common cause is that your sampling frequency is too high and the
DSP isn't fast enough to keep up. Specially if you use NLMS, which involoves
division by a variable, DSP just hasn't enough computation power. Estimate
the MIPS required by your algorithm first or do LMS first.

Wei