hsolpsav.m

DSP课程的Matlab程序

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

% High-speed Overlap-Save method of block convolutions using FFT

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

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

% y = output sequence

% x = input sequence

% h = impulse response

% N = block length (must be a power of two)

%

N = 2^(ceil(log10(N)/log10(2));

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

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

h = fft(h,N);

%

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

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

Y = zeros(K+1,N);

for k=0:K

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

	Y(k+1,:) = real(ifft(xk.*h));

end

Y = Y(:,M:N)'; y = (Y(:))';