function [x,f,s]=gensig(N,Fe,F,A)
Te=1/Fe;
t=((1:N)/Fe)';
x=sin(2*pi*t*F(:)')*A(:);
f=(0:N/2-1)*Fe/N;
y=fft(x,N)/N;
s=2*abs(y(1:(N/2)));
