Pilot Symbol Assisted QAM

Hi,

How the pilot symbol assisted QAM works ?

What are the symbol information sent on this Pilot ?

It's in the same frequency band than the QAM modulation ?

I think we send a BPSK pilot over the QAM modulation in time duplex ?

Do you have good paper on that, I found nothing over google...

Thanks

patrick.melet@dmradiocom.fr wrote:

> Hi,
> 
> How the pilot symbol assisted QAM works ?

It works well, if you don't ask too much.

> 
> What are the symbol information sent on this Pilot ?

A training sequence known to the receiver.

> 
> It's in the same frequency band than the QAM modulation ?

Yes, and that's the whole point.

> 
> I think we send a BPSK pilot over the QAM modulation in time duplex ?

Yes. The pilot is time multiplexed with the information bearing signal. 
The pilot can be any signal with the uniform spectrum like QAM.

> Do you have good paper on that, I found nothing over google...

The pilot is used for the periodical training of the equalizer to 
alleviate the multipath effects.


Vladimir Vassilevsky

DSP and Mixed Signal Design Consultant

http://www.abvolt.com