Title :
Experiment on Coherent Optical RZ 8-Star QAM Systems Using Decision-Aided Maximum Likelihood Phase Estimation
Author :
Zhang, Hongyu ; Zhang, Banghong ; Yu, Changyuan ; Kam, Pooi-Yuen
Author_Institution :
Dept. of Electr. & Comput. Eng., Nat. Univ. of Singapore, Singapore, Singapore
Abstract :
In this letter, a return-to-zero 8-star quadrature amplitude modulation (QAM) signal is generated for the first time by using a parallel I/Q modulator followed by an amplitude modulator with binary drive signals. Our experimental results verify the theoretically derived approximate bit-error rate and ring ratio optimization algorithm of the 8-star QAM. Decision-aided maximum likelihood phase estimation (PE) shows comparable performance with V&V Mth-power PE, but with much less computational complexity.
Keywords :
amplitude modulation; computational complexity; error statistics; light coherence; maximum likelihood estimation; optical modulation; optical pulse generation; optimisation; phase estimation; quadrature amplitude modulation; amplitude modulator; approximate bit-error rate; binary drive signals; coherent optical RZ 8-star QAM systems; computational complexity; decision-aided maximum likelihood phase estimation; parallel I/Q modulator; return-to-zero 8-star quadrature amplitude modulation signal; ring ratio optimization algorithm; Bit error rate; Optical noise; Optical receivers; Optimized production technology; Phase estimation; Quadrature amplitude modulation; Signal to noise ratio; Coherent optical communications; modulation format; phase estimation; phase noise;
Journal_Title :
Photonics Technology Letters, IEEE
DOI :
10.1109/LPT.2012.2223207
