[LFM,fre1,FLFM]=lffm1(BW,n,T)

%function for Input LFM signal generation
function [LFM,fre1,FLFM]=lffm1(BW,n,T)
fc=10*10^6;
alpha=(BW)/(T);%chirp rate
disp(alpha);
t=linspace(-T/2,T/2,n);%time interval
ichannel=cos(2*pi*((fc)*t+alpha*t.^2));%real part
%imaginary part
qchannel=sin(2*pi*((fc)*t+alpha*t.^2));
%computing linear frequency modulating waveform
LFM=(ichannel+(1i*qchannel));
LFM(2:1:10)=0;
LFM(504:1:511)=0;
disp(LFM);
freqmin=fc-BW/2;%minimum frequency at t= -T/2;
freqmax=fc+BW/2;%maximum frequnecy at t=  T/2;
fre1=linspace(freqmin,freqmax,n);% frequency limitations
FLFM=fftshift(fft(LFM));
%plot(fre1,abs(FLFM));
end