Guo Qi, Tran An Vu
National ICT Australia, Level 2, Building 193, University of Melbourne, Parkville 3010, Australia.
Opt Express. 2011 Dec 12;19(26):B181-90. doi: 10.1364/OE.19.00B181.
High data-rate upstream transmission in wavelength division multiplexed passive optical network (WDM-PON) based on reflective semiconductor optical amplifier (RSOA) is limited by severe inter-symbol interference (ISI), owing to low-bandwidth transmitter and fiber dispersion. To overcome the limitations in RSOA-based WDM-PON, we propose a novel receiver based on partial response maximum likelihood (PRML) equalization which combines the use of partial response (PR) signaling with maximum likelihood sequence estimation (MLSE). MLSE has been long considered as the optimal reception technique to overcome various types of impairment in optical transmission such as dispersions. It is demonstrated in this paper that PRML surpasses standard MLSE in ISI and reflection suppression with reduced complexity for RSOA-based WDM-PON system. 150 km unidirectional distance is demonstrated for 10 Gb/s uplink, while bidirectional uplinks up to 50 km and 20 km are achieved for data rate of 10 Gb/s and 20 Gb/s respectively, in WDM-PON using PRML. Furthermore, the impacts of discrete reflections on various equalization techniques are investigated, where PRML also shows superiority over MLSE.
基于反射半导体光放大器（RSOA）的波分复用无源光网络（WDM-PON）中的高数据速率上行传输受到严重符号间干扰（ISI）的限制，这是由于低带宽发射机和光纤色散所致。为了克服基于RSOA的WDM-PON中的这些限制，我们提出了一种基于部分响应最大似然（PRML）均衡的新型接收机，该接收机将部分响应（PR）信令与最大似然序列估计（MLSE）结合使用。长期以来，MLSE一直被视为克服光传输中各种损伤（如色散）的最佳接收技术。本文证明，对于基于RSOA的WDM-PON系统，PRML在ISI和反射抑制方面优于标准MLSE，且复杂度降低。在使用PRML的WDM-PON中，对于10 Gb/s上行链路，单向传输距离达到150 km，而对于10 Gb/s和20 Gb/s的数据速率，双向上行链路分别达到50 km和20 km。此外，还研究了离散反射对各种均衡技术的影响，其中PRML也显示出优于MLSE的性能。
