Real and Complex value for AWGN & multipath channel

Hi,

I noticed that the value for AWGN & multipath channel could be real &
complex value.

Thus, in a practical wireless system, these values should be real or
complex? For simulation purpose, when should I apply the real value and
when should I apply the complex value? Or it is dependent on the
transmitted signal?

Many thanks.

Richard

Richard_K wrote:
> Hi,
>
> I noticed that the value for AWGN & multipath channel could be real &
> complex value.
>
> Thus, in a practical wireless system, these values should be real or
> complex? For simulation purpose, when should I apply the real value and
> when should I apply the complex value? Or it is dependent on the
> transmitted signal?
>
> Many thanks.
>
> Richard

  In my opinion,it depends on the transmitted signal.
  youyou

Depends on your transmitted signal

In passband simulation when you have upconverted your baseband signal
to the carrier frequency - it becomes real - so you have to add a real
valued noise to it.

In baseband simulation when the signal is still in the form of Inphase
and Quadrature phase components you have to add a complex valued noise
to it.

HTH

Richard_K wrote:
> Hi,
>
> I noticed that the value for AWGN & multipath channel could be real &
> complex value.
>
> Thus, in a practical wireless system, these values should be real or
> complex? For simulation purpose, when should I apply the real value and
> when should I apply the complex value? Or it is dependent on the
> transmitted signal?
> 
> Many thanks.
> 
> Richard