Please check these

http://www.circuitsgallery.com/2012/07/matlab-code-for-frequency-modulation-fm.html

http://www.circuitsgallery.com/2012/05/matlab-code-for-amplitude-modulation-am.html

Regards

Sajith

Sir 

You are not getting my point.Please sir go through point no. D on page 3 of attach pdf.

Dear sir

Just to advise you, try to contact the author of this paper, he could help you.

Best regards

Did you try Matlab Central? It is an open forum. You can also find FileExchange there and download sample codes free.

http://www.mathworks.com/matlabcentral/

Bandwidth is basically the range of frequencies so just have look at the FM and AM and you can guess what should be the bandwidth of these signlas

If you have signal or vector x in time and you want to observe X in frequency domain all you need to do is this: 

%fs is the sampling frequency of the vector x ( meaning that if x(1) occurs at 0 and x(2) %occurs at 0.5 sec that means your sampling period is Ts= 0.5 sec and your sampling frequency is fs = 1/Ts = 2 Hz)

X = fftshift(fft(x));

f = [0:length(input)-1]*fs/(length(input)-1);

f = f - fs/2;

And here you go ;) 

hope this helps

For Matlab Code, Visit link

http://dg-algorithm.blogspot.com/