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single or multitone cancellor

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ayina

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i am doing work on a project in which undesired frequencies are added as noise in base band communication signal. now i want to cancel that frequency effect by estimating its amplitude ,phase and frequency. there are two approaches in my mind
1) notch filter (but it is not so reasonable atleast for my work)
2)estimating its amplitude ,phase and frequency. i want to adapt that.
kindly give me suggestion and code to implement that in matlab
 

i wrote the code for this but it is for known frequency interference cancellation.

%% step 1 proj adsp
clear;
clc
close all;
N=2000;
Fs=1000;
Length=Fs*10;
f_signal=20/Fs;
x=sin(2*pi*20/Fs*(1:N));
%plot (x)
f1=50;%freq of noise signal in Hz
i=1:length(x);
Noise_signal = sin(2*pi*f1*i/Fs); % Power Line Interference
n=Noise_signal;
% Range of the Noise Signal embedded in the signal x
Mixed = x+ Noise_signal; % received Signal with periodic Noise
%%%%%%%%%%%%%%%% POWER LINE INTERFERENCE %%%%%%%%%%%%%%%

%% LMS algo for adaptive filtering
m=Mixed;
d=x+n+m;
n1=rand()*Noise_signal;% harmonic noise with some unknown amplitude
FilterTap=16;
w=ones(FilterTap,1);% no of taps of estiamted filter
mu=0.05; % Lest Mean Square (LMS) step size.

for i=1:length(x)

if i<FilterTap
u=[n1(i:-1:1) ,zeros(1,FilterTap-i)]';
else
u=[n1(i:-1:i-(FilterTap-1))]';

end

y(i)=w'*u;
e(i)=d(i)-y(i);
w=w+mu*u*e(i);
if (sum(w)<=10^-9)
break
end
end
d_ref=conv(w,x);
plot(e)
figure(2)
plot(x)
figure(3)
plot(m)
Output_without_Noise_signal=e;
M=100;
fc=0.25;
for i=1:M
h(i)=sin(2*pi*fc*(i-M/2))*(0.42- 0.5*cos(2*pi*i/M) + 0.08*cos(4*pi/M) )/(i-M/2);
end
h(ceil(M/2))=2*pi*fc;
h=h/sum(h);
Final_filter_Output=filter(h,1,Output_without_Noise_signal);
figure(4),plot(Final_filter_Output)
plot(abs(fft (Final_filter_Output)))
figure(5)
plot(abs(fft(m)))
chech this all of you. here final_filter_output has just changed amplitude. mean amplitude detection is somewhat false. all idea are welcomed.
 

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