function y = slow_circonv(x,h,N);

% Slow circular convolution ....
% y = slow_circonv(x,h,N)
% x, h = input and sample response vectors
% N is size of circular buffer
% Convolution is implemented without any MATLAB efficiencies

lenx = length(x);
lenh = length(h);
lent = lenx+lenh-1;
x = [x zeros(1,lenh-1)];
h = [h zeros(1,lenx-1)];
y = zeros(1,lenx+lenh-1);
for n = 1:lent, 
        for k = max(1,2-lenh):min(n,lenx),
	       y(n) = y(n) + x(k)*h(1+n-k); % adjustment for indexing from 1
        end
if(rem(n,100))==0
	disp(n)
	end
		end
		

for n = N+1:lent,
        y(rem(n,N)) = y(rem(n,N)) + y(n);
end

leny = length(y);
if(N<leny) y = y(1:N);
end
if(N>leny)y = [y zeros(1,N-leny)];
end