> If the constellation spins rather slowly, and the equalizer adapts
> fairly quickly, you can actually track the constellation's spinning in
> the equalizer, and be able to decode the data. This is a *really* nasty
> botch, though, and you can't expect to demodulate high order QAM this
> way. You can kinda decode 16-QAM at high SNR - interesting for
> experimenting, but not much use in a system.
You are right.
With 16-QAM at high SNR, when the constellation spins rather slowly,
and the training curve of the equqlizer converge. Though, as you said
before, it is meaningless.
Has anybody observed the frequency response of a adaptive equalizer?
It is well known that the magnitude response of "zero-forcing
equalizer" is just the inverse of channel magnitude response? Then, how
about adaptive equalizer?
I think the response of the adaptive equalizer may look like the one of
"zero-forcing equalizer". The difference is amplitude response of the
adaptive equalizer is not as high as "zeroforcing equalizer", when the
amplitude response of channel is really small.
Am I right?