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Time Frequency Toolbox >> Time Frequency Toolbox > Linear Time-Frequency Processing > tffilter

tffilter

Time frequency filtering of a signal.

Calling Sequence

Y=tffilter(TFR,X,T)
Y=tffilter(TFR,X,T,TRACE)

Parameters

X :

input signal (must be analytic).

T :

time instant(s) (default : 1:length(X)).

TRACE :

if nonzero, the progression of the algorithm is shown (default : 0).

TFR :

Wigner-Ville distribution of the filter frequency axis is graduated from 0.0 to 0.5.

Description

tffilter filters the signal X with a non stationary filter.

Examples

Nt=128; t=1:Nt; sig=fmlin(Nt,0.05,0.3)+fmlin(Nt,0.2,0.45);
sig(Nt/2)=sig(Nt/2)+8; figure(1);tfrwv(sig,t);
Nf=128;freqs=0.5*(0:Nf-1).'/Nf;
for tloop=1:Nt,
rate=0.2*(tloop-1)/(Nt-1);
H(:,tloop)=(0+rate<freqs).*(freqs<0.1+rate);
end;
y=tffilter(H,sig,t,1);figure(2); tfrwv(y,t);

Nt=128; t=1:Nt; sig=atoms(128,[64 0.25 sqrt(128) 1]);
figure(1);tfrwv(sig,t);
Nf=64;
H=zeros(Nf,Nt);H(Nf/4+(-15:15),Nt/2+(-15:15))=ones(31);
y=tffilter(H,sig,t,1);figure(2); tfrwv(y,t);
See also:
tfristft

Authors

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