Pilot-aided Carrier Phase Estimator for Quadrature Amplitude Modulation in Fibre Communications

With the development of optical communication technology, Quadrature Amplitude Modulation (QAM) has been widely used in fibre communication systems, However, conventional phase estimation algorithms can't effectively estimate the phase noise of high-order QAM signals. In this paper, a pilot-aided phase noise estimator has been studied. By using pilot-aided algorithm, the proposed phase estimator can be applied to arbitrary quadrature amplitude modulation (QAM) scheme. The estimator is composed of a one-shot estimator and Wiener filter to achieve optimal performance. This paper discusses the structure and theory of this phase noise estimator.