how can i apply wavelet filter to this code

% generate a waveform 
f0 =100;  
fs=1000;  
pw = 0.1; 
pri = 1; 
npulses = 100;
s = cos(2*pi*f0*(0:1/fs:pw));      % it can be any other waveform of your choice
s(round(fs*pri)) = 0;               % PRI
s = repmat(s, npulses, 1); % npulses
% echo: delayed signal
tau = 0.3;  
ntau = round(fs*tau); 
amp = 0.5;
e = amp* circshift(s, ntau);
% add noise
sigma = 0.1;
r = s + e + sigma*randn(size(s));
y = pulsint(r);
plot((0:length(s)-1)/fs, r)