How are you everyone.
In OFDM links, do we need frequency-domain equalization(FDE), after FFT block of
the receiver?
In books, it seems that FDE is need if we have a TEQ (channel shortening time
domain equalizer) as was studied by Al-Dhahir, etc.
With TEQ, there will be phase errors, and I think that FDE can restore the
phase.
But I think that we don't actually use TEQ in OFDM links most of the time,
thus we won't need FDE either.
Can I hear your advice on this, please?
Thank you in advance.
OFDM and frequency-domain equalization
Started by ●July 24, 2007
Reply by ●July 26, 20072007-07-26
For mobile OFDM-based systems such as DVB-H or 802.16e where
inter-subcarrier interference due to the Doppler effect will be a major
problem, you WILL need equalization. FDE approaches are effective and fairly
easy to implement. Not too sure about time-domain approaches, though.
HTH
Sameer
On 7/19/07, l...@hotmail.com wrote:
>
> How are you everyone.
>
> In OFDM links, do we need frequency-domain equalization(FDE), after FFT
> block of the receiver?
>
> In books, it seems that FDE is need if we have a TEQ (channel shortening
> time domain equalizer) as was studied by Al-Dhahir, etc.
>
> With TEQ, there will be phase errors, and I think that FDE can restore the
> phase.
>
> But I think that we don't actually use TEQ in OFDM links most of the time,
> thus we won't need FDE either.
>
> Can I hear your advice on this, please?
>
> Thank you in advance.
>
>
>
inter-subcarrier interference due to the Doppler effect will be a major
problem, you WILL need equalization. FDE approaches are effective and fairly
easy to implement. Not too sure about time-domain approaches, though.
HTH
Sameer
On 7/19/07, l...@hotmail.com wrote:
>
> How are you everyone.
>
> In OFDM links, do we need frequency-domain equalization(FDE), after FFT
> block of the receiver?
>
> In books, it seems that FDE is need if we have a TEQ (channel shortening
> time domain equalizer) as was studied by Al-Dhahir, etc.
>
> With TEQ, there will be phase errors, and I think that FDE can restore the
> phase.
>
> But I think that we don't actually use TEQ in OFDM links most of the time,
> thus we won't need FDE either.
>
> Can I hear your advice on this, please?
>
> Thank you in advance.
>
>
>
Reply by ●July 31, 20072007-07-31
Hi Guys,
Have you ever implemented the PAPR reduction technique called Partial Transmit Sequence Technique. I implemented it but not getting the reported PAPR improvement in the papers. I am doint the phase rotation after the induvidual ifft (of the same size as the original OFDM). If you feel any likely mistakes on this, could you pls guide me.
Rgds,
Janaa
Have you ever implemented the PAPR reduction technique called Partial Transmit Sequence Technique. I implemented it but not getting the reported PAPR improvement in the papers. I am doint the phase rotation after the induvidual ifft (of the same size as the original OFDM). If you feel any likely mistakes on this, could you pls guide me.
Rgds,
Janaa
