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 :) On 03/12/2015 07:35 AM, Vishwanatha H G wrote: > sir, can we achieve 16 qam demodulation constellation without using > costas loop? if possible please send me the flow graph. thank you > > > _______________________________________________ > Discuss-gnuradio mailing list > Discuss-gnuradio@gnu.org > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
_______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio