March 10, 2011 / Vol. 9, No. 3 / CHIN ES E OPTICS LETTERS 030602-1
Electronic compensator for 100-Gb/s PDM-CO-OFDM
long-haul transmission systems
Xuejun Liu (
444
ÆÆÆ
)
1,2
, Yaojun Qiao (
zzz
)
1
, and Yuefeng Ji (
VVV
¸¸¸
)
1∗
1
Key Laboratory of Information Photonics and Optical Communications, the Ministry of Education,
Beijing University of Posts and Telecommunications, Beijing 100876, China
2
College of Information Science and Engineering, Yanshan University, Qinhuangdao 066004, China
∗
Corresponding author: jyf@bupt.edu.cn
Received September 29, 2010; accepted November 6, 2010; posted online February 21, 2011
We study an electronic compensator (EC) as a receiver for a 100-Gb/s polarization division multiplexing
coherent optical orthogonal frequency division multiplexing (PDM-CO-OFDM) system without optical
dispersion compensation. EC, including electrical dispersion compensation (EDC), least squares chan-
nel estimation and compensation (LSCEC), and phase compensation (PC), is used to compensate for
chromatic dispersion (CD), phase noise, polarization mode dispersion (PMD), and channel impairments,
respectively. Simulations show that EC is highly effective in compensating for those impairments and
that the performance is close to the theoretical limitation of optical signal-to-noise rate (OSNR), CD, and
PMD. Its robustness against those transmission impairments and fiber nonlinearity are also sy stematically
studied.
OCIS codes: 060.4510, 060.1660, 060.2430.
doi: 10.3788/COL201109.030602.
Optical orthogonal frequency division multiplexing
(OFDM) has been a main research interest in recent
years
[1]
. Coherent optical OFDM (CO-OFDM) com-
bined with polarization division multiplexing (PDM) is
regarded as a promising technology for high-speed optical
transmission as it can provide powerful channel estima-
tion a nd comp e nsation capabilities and can also double
the spectra l efficiency of a tr ansmission system
[2]
. In
contrast with the conventional design, the CO-OFDM
systems do not use any dispers ion compensation fiber
[3]
;
thus, it is important to conduct research on the pe rfor-
mance of the PDM-CO- OFDM systems without optical
dispersion c ompensation (ODC).
Recently, many studies have focused on using electronic
compensators (ECs) at the receiver of CO-OFDM
[4−8]
.
The use of electronic signal processing to comp e ns ate for
chromatic dispersion (CD), phase noise, and polarization
mode dispersion (PMD) in optical transmission offers the
advantages of low cost, small size, reduced optical losses,
and adaptive ope ration. However, these studies did not
systematically conduct research on combining each com-
pens ation algorithm.
In this letter, we conduct simulation a nalysis on using
an EC at the receiver to compensate for CD, phase noise,
PMD, and channel impairments on a 100-Gb/s PMD-
CO-OFDM system; her e , EC includes electrical disper-
sion compensation (EDC), least squares channel estima-
tion and compensation (LSCEC), and phase compensa-
tion (PC). We systematically study EC against transmis-
sion impairments, and the numerical simulations show
that the EC is very effective in compensa ting for impair-
ments in systems.
Assuming a long-enough symbol period, the channel
model for the kth subcarrier in the ith symbol in PDM-
CO-OFDM systems is give n by
[9]
r
′
ik
= e
jφ
D
(k)
· e
jφ
k
· H
k
· t
ik
+ n
ik
, (1)
or
"
r
′x
ik
r
′y
ik
#
= e
jφ
D
k
· e
jφk
·
"
h
xx
(k) h
xy
(k)
h
yx
(k) h
yy
(k)
#
·
"
t
x
ik
t
y
ik
#
+
"
n
x
ik
n
y
ik
#
, (2)
where t
ik
= (t
x
ik
t
y
ik
)
t
and r
ik
= (r
′x
ik
r
′y
ik
)
t
are the trans-
mitted and received information symbols, respectively, in
the form of the Jones vector for the kth subcarrier in the
ith OFDM symbol; n
ik
= (n
x
ik
n
y
ik
)
t
is the noise including
two polarization components. A multiple-input Multiple-
output (MIMO) model essentially relates the two out-
puts, r
′x
ik
and r
′y
ik
, to the two inputs, t
x
ik
and t
y
ik
[9]
. H
k
is the 2×2 Jones matrix for the fiber link representing
the linear channel effects, and φ
k
is the OFDM symbol
phase noise owing to the phase noises from the lasers and
radio fre quency (RF) local oscillators (LOs) at both the
transmitter and receiver
[10]
, w hich is usually dominated
by the laser linewidth. φ
D
(f
k
) is the phase dispersion
owing to the fiber CD
[10]
given by
φ
D
(f
k
) =
π · c
f
2
LD
D
t
· f
2
k
, (3)
where f
LD
is the frequency of the optical carrier, c is
the speed of light (m/s), D
t
is the total accumulated
CD in units of ps/nm, and f
k
is the frequency for the
kth subcarrier. To compensate for channel impairments
in the PDM-CO-OFDM systems without ODC, the EC
is located after fast Fourier transform (FFT) in the re-
ceiver and includes three parts, namely, EDC, LSCEC,
and PC, that are used to estimate φ
D
(f
k
), H
k
, and φ
k
,
respectively. T he location of EC is s hown in Fig. 1, and
the setup is shown in Fig. 2.
1671-7694/2011/030602(5)
c
2011 Chinese Optics Letters
资源评论
weixin_38746818
- 粉丝: 7
- 资源: 910
最新资源
- 易优CMS响应式模板PHP+Mysql+E000673职业教育培训机构网站模板.zip
- 淘系对账实操课程详解：从订单处理到绩效工资核算，全面掌握电商财务管理.mp4
- Linux-C编程一站式学习-最新版
- 2021新版散热器风扇马达组装生产线（sw20可编辑+工程图）全套技术资料100%好用.zip
- KR C5 控制柜安装指南中文说明书
- 玩转小红书电商：从选品到上架，再到笔记发布与流量获取，一站式指南.mp4
- 突破销售瓶颈，掌握销冠三火轮，实现业绩持续增长的销售技能课.mp4
- 详细教你自媒体视频二剪搬运技术，自己加工100%过原创，无脑搬运.mp4
- Kaggle实战之Rossmann商店销售预测数据
- Muse-Ant-Desgin-Vue 改造成vue3的代码
- 小红书电商项目全解析，包括账号搭建、店铺运营、笔记发布 实现流量变现.mp4
- 小红书电商引流教程：从基础操作到发布内容，引流技巧，轻松打造爆款产品.mp4
- 前端开发领域中JavaScript语言的基础理论与实战指南
- RTA-OS3.1-Reference-Guide
- linux下的webstorm的deb安装包002
- 小红书实战训练营：精准定位用户，传授六个技巧，助你写出爆款笔记.mp4
资源上传下载、课程学习等过程中有任何疑问或建议，欢迎提出宝贵意见哦~我们会及时处理！
点击此处反馈
