ovrlpsav.m

Digital Signal Processing Using MATLAB V.4随书代码

function [y] = ovrlpsav(x,h,N)

% Overlap-Save method of block convolution

% ----------------------------------------

% [y] = ovrlpsav(x,h,N)

% y = output sequence

% x = input sequence

% h = impulse response

% N = block length

%

Lenx = length(x); M = length(h);

M1 = M-1; L = N-M1;

h = [h zeros(1,N-M)];

%

x = [zeros(1,M1), x, zeros(1,N-1)]; % preappend (M-1) zeros

K = floor((Lenx+M1-1)/(L));         % # of blocks

Y = zeros(K+1,N);

% convolution with succesive blocks

for k=0:K

	xk = x(k*L+1:k*L+N);

	Y(k+1,:) = circonvt(xk,h,N);

end

Y = Y(:,M:N)';                      % discard the first (M-1) samples

y = (Y(:))';                        % assemble output