Spectrally Efficient Quadrature Duobinary Coherent Systems With Symbol-Rate Digital Signal Processing

被引：37

作者：

Li, Jianqiang ^{[1
]}

Tao, Zhenning ^{[1
]}

Zhang, Huijian ^{[1
]}

Yan, Weizhen ^{[1
]}

Hoshida, Takeshi ^{[2
]}

Rasmussen, Jens C. ^{[2
]}

机构：

[1] Fujitsu R&D Ctr, Beijing 100025, Peoples R China

[2] Fujitsu Labs Ltd, Kawasaki, Kanagawa 2118588, Japan

来源：

JOURNAL OF LIGHTWAVE TECHNOLOGY | 2011年 / 29卷 / 08期

关键词：

Coherent detection; high spectral efficiency; optical communications; quadrature duobinary (QDB); BLIND EQUALIZATION; PHASE;

D O I：

10.1109/JLT.2011.2105461

中图分类号：

TM [电工技术]; TN [电子技术、通信技术];

学科分类号：

0808 ; 0809 ;

摘要：

An enhanced digital coherent receiver including a novel blind equalization approach and maximum-likelihood sequence detection (MLSD) is proposed for dual-polarization quadrature duobinary (DP-QDB) systems. In virtue of the compact spectrum of DP-QDB signals approaching Nyquist limit, the equalization is implemented at symbol rate, which relaxes the demand on the sampling speed of analog-to-digital converters (ADCs). The proposed symbol-rate receiver is verified by 43 Gb/s experiments in the presence of chromatic dispersion and polarization-mode dispersion. This paper also investigates the tolerances to narrowband optical filtering, ADC sampling phase, duobinary-generating filter bandwidth, laser linewidth, and carrier frequency offset. Detailed modulation format comparisons are made among DP-QDB, DP-quadrature-phase-shift keying (QPSK), DP-8 quadrature amplitude modulation (QAM), and DP-16QAM. It is shown that DP-QDB with MLSD well trades off major requirements on advanced modulation formats.

引用

页码：1098 / 1104

页数：7

共 23 条

[1] Compensation of Quadrature Imbalance in an Optical QPSK Coherent Receiver [J].