Non Data Aided Phase Estimation Techniques for QAM Communication System: A Review
Phase recovery is a problem of paramount importance in synchronous digital communication system, especially for high bit rate signaling such as QAM modulation. The phase estimation must be performed in a blind manner, means without using known training sequences of known transmitted symbols i.e. known as Non-Data-Aided (NDA) method. This is done to obtain high efficienc.y. Accuracy in estimation of phase is very important because if it is little off, cross talk occurs. Recent advances in phase estimation have paved the way for simple calculation and improved results. Many authors have addressed this topic over the last year, yielding a wide variety of recovery methods. In this paper, complete review for NDA phase estimation techniques explained with its achievements and limitations.