OFDM uses null DC. Why?

Hi~ everybody~

I have one thing about OFDM to want to know.

In general OFDM system, DC sub-carrier is not used, that is, null is
inserted there.
Suddenly I come to curious about the reason.
According to the some documents that I found in the web, the reason is
due to direct conversion which cannot pass DC component.

Is it correct?
and is it the only reason why DC sub-carrier was stuffed with zero?

Any response would be helpful to me.

Thanks for reading and have a nice day!

- Mabinogi -

The reason is that you can remove the DC offset by applying a DC
blocking filter since there is no information around DC. The DC offset
is a very big problem in receiver design and it is much larger in
Direct-Conversion receiver.


Mabinogi =E5=AF=AB=E9=81=93=EF=BC=9A

> Hi~ everybody~
>
> I have one thing about OFDM to want to know.
>
> In general OFDM system, DC sub-carrier is not used, that is, null is
> inserted there.
> Suddenly I come to curious about the reason.
> According to the some documents that I found in the web, the reason is
> due to direct conversion which cannot pass DC component.
>
> Is it correct?
> and is it the only reason why DC sub-carrier was stuffed with zero?
>
> Any response would be helpful to me.
>=20
> Thanks for reading and have a nice day!
>=20
> - Mabinogi -