JOURNAL OF SHENZHEN UNIVERSITY SCIENCE AND ENGINEERING

The enhancement of optical coherent detection by amplitude estimation

Hui Wang

Published Jan 1, 2011• 0 citations

Abstract

In optical coherent communication systems,balanced photodetectors were typically employed.Such photodetectors preserved the product of the received optical signals and the local oscillators(LO) for detection but cancelled out the power of both.A new detection scheme which aims to maintain the full information obtained from the photodetectors was proposed.Not only the product of the signals and the LO but also the power of signals were used to estimate the amplitude of the target signals.For 16-qudrature-amplitude-modulation(16-QAM) and 64-QAM signals,the simulation results show that the new scheme can outperform the conventional balanced detection method by more than 1 dB in SNR.

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