Time-domain digital pre-equalization for band-limited signals based on receiver-side adaptive equalizers.
Time-domain digital pre-equalization for band-limited signals based on receiver-side adaptive equalizers.
复制标题
DOI：
10.1364/oe.22.020515
复制
发表时间：
2014-08
期刊：
影响因子：
3.8
通讯作者：
Junwen Zhang;Jianjun Yu;N. Chi;H. Chien
中科院分区：
文献类型：
--
作者：
Junwen Zhang;Jianjun Yu;N. Chi;H. Chien
本文从理论和实验上研究了一种适用于带宽受限光相干通信系统的时域数字预均衡（DPEQ）方案，该方案基于接收端盲均衡器和自适应均衡器（如最小均方（LMS）算法和常数或多模算法（CMA，MMA））对信道特性的反馈。基于所提出的DPEQ方案，我们从理论和实验上研究其性能的各种信道条件以及分辨率的信道估计，如滤波带宽，抽头长度，和OSNR。采用高速64-GSa/s DAC与DPEQ技术相结合，成功合成了偏振分离复用（PDM）、正交相移键控（QPSK）、8正交幅度调制（QAM）和16正交幅度调制（16 QAM）等调制格式的带限40-Gbaud信号，并在背靠背和传输误码性能方面得到了显著改善。
We theoretically and experimentally investigate a time-domain digital pre-equalization (DPEQ) scheme for bandwidth-limited optical coherent communication systems, which is based on feedback of channel characteristics from the receiver-side blind and adaptive equalizers, such as least-mean-squares (LMS) algorithm and constant or multi- modulus algorithms (CMA, MMA). Based on the proposed DPEQ scheme, we theoretically and experimentally study its performance in terms of various channel conditions as well as resolutions for channel estimation, such as filtering bandwidth, taps length, and OSNR. Using a high speed 64-GSa/s DAC in cooperation with the proposed DPEQ technique, we successfully synthesized band-limited 40-Gbaud signals in modulation formats of polarization-diversion multiplexed (PDM) quadrature phase shift keying (QPSK), 8-quadrature amplitude modulation (QAM) and 16-QAM, and significant improvement in both back-to-back and transmission BER performances are also demonstrated.