(no subject)

sir, can we achieve 16 qam demodulation constellation without using
costas
loop? if possible please send me the flow graph. thank you

Hi Vishwanatha,

Demodulation of phase-depending modulations requires some kind of
synchronization.

There’s more approaches than costas loops to phase synchronization;
however, they’re usually very specific to a channel/signal model and
can’t be universally applied, or very inefficient, or very complicated
to explain. So the important question here is: Why do you need something
else than a phase error feedback loop? You can of course just estimate
your phase offset once using a set of known symbols (e.g. a preamble),
and use that for as long as you think your channel and transceiver are
coherent, but I think you’ve already considered that, since you ask how
to get rid of the loop, and recognized that it’s a good idea to
continuously account for changing phase.

Greetings,
Marcus

PS: There’s not only sirs on this list, also ladies, and we’re not very
formal on here, so a quick “hello” would totally be sufficient :slight_smile: