How to represent a complex function in modulo

Question

Alber 2020-11-2

回答： Rohit Pappu 2020-11-25

Hi,

I would like to represent this function where w goes from 0 to 250 kHz and B is 1. My code is as follows:

w = [0:1:249];
B1 = 0.5;
B2 = 1;
fc = 100;
to = 10*10^6;
a =exp(i*2*pi*fc*to);
b = exp(i*w*to);
c = 2*pi*dirac(w)-(B2*(a.*b));
stem(abs(c))

What I want to do is render the module of the function, but I'm getting this, which I think is wrong and I don't know where I'm failing...

I want to represent this function:

Thank you very much in advance.

Answer 1

Rohit Pappu 2020-11-25

Intuitively speaking, at line no. 9

stems(abs(c));

is 0 everywhere except at ω = 0 .

= inf .

= β for all values of ω

Hence abs( c ) is always β except at ω = 0. Thus, stem(abs( c )) returns the above graph