function [y]=OFDM_Modulator(data,NFFT,Ng,numcarr);
x=zeros(1,NFFT);
%Zero padding
for i=1:numcarr
    x(1,i+NFFT/2-numcarr/2)=data(1,i);
end
%ifft
a=ifft(x);
%insert the guard interval
y=[a(NFFT-Ng+1:NFFT),a];

clear data x a;