In band noise

Hi

I have to work on a received signal (COFDM signal, with several thousands
of subcarriers), after a AWGN channel. I would like to reduce noise.
First, bandpass filtering is done. Then, I have to reduce the in-band
noise. Do you know some methods to do it? (I know for instance that the
optimal Wiener filter can do that, but I don't how to build it with only
an access to the noisy signal).

Thank you in advance. 

thom skrev:
> Hi
>
> I have to work on a received signal (COFDM signal, with several thousands
> of subcarriers), after a AWGN channel. I would like to reduce noise.
> First, bandpass filtering is done. Then, I have to reduce the in-band
> noise. Do you know some methods to do it? (I know for instance that the
> optimal Wiener filter can do that, but I don't how to build it with only
> an access to the noisy signal).

Do you have any knowledge of what would have been recieved
on a noise-free chanel (I think the technical term is "codebook"
but I am not sure; communication is not my strongest subject)?
If so, would this knowledge help when designing the Wiener filter?

Rune

No I don't have a priori knowledge about the original signal. So I don't
even know if it's possible to implement this kind of filter by a direct
method.