高速相干光通信系统中信道均衡补偿的研究
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摘要
随着近些年来互联网、多媒体数据等业务的飞速发展,人们对长距离大容量的传输系统的需求就越来越大。光纤具有损耗小、带宽大的优点,能够容纳极大的信息量,自从问世以来就受到广泛的研究和关注。光纤传输系统的容量已经从初期阶段的10G逐渐增大到40G甚至100G,系统的升级一方面满足了人们的需求,但是另一方面也带来了很多问题。光纤中存在着损耗、色散、偏振模色散和非线性效应等损伤,随着传输速率的增加,这些损伤会极大地降低传输效果,设计能够有效地补偿和恢复这些损伤的接收方案势在必行。另外,发射端的实现复杂度也会随着系统的升级而大大增加,设计简单的发射方案并生成高速信号也是必不可少的。
近些年来,灵活的相干接收方案发展十分迅速。相干接收机将传输信号从光域线性地变换到电域,完整地保留了信号的相位和偏振态信息。在接收机的数字信号处理模块中,多种电域算法能够很好地补偿和恢复信号受到的损伤。相应地,发射端可以采用高阶相位调制格式并结合复用技术来提高信号的频谱利用率,比如相移键控格式(M-PSK)或正交幅度调制格式(M-QAM)。
本文针对高速相干光纤通信系统以及部分信道均衡补偿算法做了理论研究和仿真实现。主要工作分为以下几部分：
1.分析了光纤中存在的多种损伤特性,包括损耗、色散、偏振模色散和非线性效应的产生机理和理论模型；
2.详细分析了相干接收系统的结构和工作原理,介绍了两种常见的接收方案,以及各个模块的功能和内部结构。阐述了16QAM信号的调制和解调过程,介绍了偏分复用的实现原理,并搭建了112Gb/s的PDM-16QAM相干接收仿真系统。
3.介绍了相干接收机中负责偏分解复用和偏振模色散补偿的均衡器的结构和工作原理,回顾了典型的均衡算法。在此基础上,针对传统算法的不足,提出了几种改进后的均衡算法,给出了算法的理论模型,并分别在112Gb/s的PDM-16QAM仿真系统中与传统算法做了传输效果的对比和分析,主要包括算法的收敛速度、最终收敛效果,对偏分复用系统中的奇异性的抵抗力等。
4.阐述了传输系统中进行载波相位恢复的必要性,介绍了载波相位恢复的原理以及典型的恢复方案,并在QPSK仿真系统中得到了验证。针对16Q信号的特点,给出了改进的接收方案,在PDM-16QAM仿真系统中验证了改进方案,并研究了相位恢复中的几个参数对系统误码率的影响。
本文的研究工作集中在高速相干光通信系统中的电域均衡补偿算法的研究,根据新型调制格式以及具体的物理模型,提出了改进的解决方案,着力于提高系统的传输效率。
Nowadays, with the rapid development of the data services on internet and multimedia fields, public's demand on the large capacity, long haul transmission system is increasing as well. Optical fiber, the small-loss and large-bandwidth media, is able to transport the tremendous amount of data, which is subjected to a wide range of research and concern since it came out. The capacity of optical transmission system has gradually increased to40G even to100G compared with10G at the beginning. On one hand, the system upgrade meets our requirement on data transmission. On the other hand, it also brings some problems. The loss, chromatic dispersion, polarization mode dispersion and nonlinear effects sharply reduce the transmission efficiency. It's imperative for us to find a receiver solution which is able to effectively compensate and restore these losses. In addition, the transmitter complexity is affected by the system upgrade, so to generate high-speed signal with a simple transmitter solution is essential as well.
In recent years, the development of flexible coherent detection is evolving rapidly. Coherent receiver linearly transfers optical signals to electrical signals, completely retaining the phase information and state of polarization. In the digital signal processing module of the receiver, there are several algorithms can effectively compensate and restore the transmission loss. Accordingly, the transmitter may use high-order modulation combined with multiplexing technique to increase the spectral efficiency, such as phase shift keying or quadrature amplitude modulation.
In this paper, I did research and simulation for high-speed coherent optical communication systems, as well as some compensation and equalization algorithms. It mainly consists of the following parts:
1. Analysis of the generation mechanisms and theoretical models of several fiber characteristics are given, including the loss, chromatic dispersion, polarization mode dispersion and nonlinear effects.
2. Detailed analysis of the structure and principle of the coherent receiver system are carried out. Two common receiver solutions, as well as the function and inner structure of each module are introduced. Explanation of modulation and demodulation process is given, and also the implementation principle of polarization division multiplexing. At last, a112Gbit/s PDM-16QAM signal is simulated in a coherent detection system.
3. The description of the structure and principle of the equalizers in the receiver is given, as well as some typical compensating algorithms. For the lack of the conventional constant modulus algorithms, several modified algorithms are developed, and the theoretical models are given, respectively. Then the modified algorithms and the conventional one are simulated in the112Gb/s PDM-16QAM system, including the convergence rate, the convergence effect and the resistance of singularity problem.
4. The necessity of carrier phase recovery is introduced, and the principles of the carrier phase recovery as well as the typical recovery solution are carried out. Then the solution is simulated in the QPSK system. According to the characteristics of16QAM format, an improved scheme is given, and also verified in the PDM-16QAM simulation system. Eventually, the impact of several parameters on the system bit error rate is studied.
In summary, this thesis is mainly about the electrical equalization and compensation in high speed coherent optical communication systems. Based on high-order modulation format as well as the physical model, some modified algorithms and solutions are carried out, in order to improve the transmission efficiency of the system.
近些年来,灵活的相干接收方案发展十分迅速。相干接收机将传输信号从光域线性地变换到电域,完整地保留了信号的相位和偏振态信息。在接收机的数字信号处理模块中,多种电域算法能够很好地补偿和恢复信号受到的损伤。相应地,发射端可以采用高阶相位调制格式并结合复用技术来提高信号的频谱利用率,比如相移键控格式(M-PSK)或正交幅度调制格式(M-QAM)。
本文针对高速相干光纤通信系统以及部分信道均衡补偿算法做了理论研究和仿真实现。主要工作分为以下几部分：
1.分析了光纤中存在的多种损伤特性,包括损耗、色散、偏振模色散和非线性效应的产生机理和理论模型；
2.详细分析了相干接收系统的结构和工作原理,介绍了两种常见的接收方案,以及各个模块的功能和内部结构。阐述了16QAM信号的调制和解调过程,介绍了偏分复用的实现原理,并搭建了112Gb/s的PDM-16QAM相干接收仿真系统。
3.介绍了相干接收机中负责偏分解复用和偏振模色散补偿的均衡器的结构和工作原理,回顾了典型的均衡算法。在此基础上,针对传统算法的不足,提出了几种改进后的均衡算法,给出了算法的理论模型,并分别在112Gb/s的PDM-16QAM仿真系统中与传统算法做了传输效果的对比和分析,主要包括算法的收敛速度、最终收敛效果,对偏分复用系统中的奇异性的抵抗力等。
4.阐述了传输系统中进行载波相位恢复的必要性,介绍了载波相位恢复的原理以及典型的恢复方案,并在QPSK仿真系统中得到了验证。针对16Q信号的特点,给出了改进的接收方案,在PDM-16QAM仿真系统中验证了改进方案,并研究了相位恢复中的几个参数对系统误码率的影响。
本文的研究工作集中在高速相干光通信系统中的电域均衡补偿算法的研究,根据新型调制格式以及具体的物理模型,提出了改进的解决方案,着力于提高系统的传输效率。
Nowadays, with the rapid development of the data services on internet and multimedia fields, public's demand on the large capacity, long haul transmission system is increasing as well. Optical fiber, the small-loss and large-bandwidth media, is able to transport the tremendous amount of data, which is subjected to a wide range of research and concern since it came out. The capacity of optical transmission system has gradually increased to40G even to100G compared with10G at the beginning. On one hand, the system upgrade meets our requirement on data transmission. On the other hand, it also brings some problems. The loss, chromatic dispersion, polarization mode dispersion and nonlinear effects sharply reduce the transmission efficiency. It's imperative for us to find a receiver solution which is able to effectively compensate and restore these losses. In addition, the transmitter complexity is affected by the system upgrade, so to generate high-speed signal with a simple transmitter solution is essential as well.
In recent years, the development of flexible coherent detection is evolving rapidly. Coherent receiver linearly transfers optical signals to electrical signals, completely retaining the phase information and state of polarization. In the digital signal processing module of the receiver, there are several algorithms can effectively compensate and restore the transmission loss. Accordingly, the transmitter may use high-order modulation combined with multiplexing technique to increase the spectral efficiency, such as phase shift keying or quadrature amplitude modulation.
In this paper, I did research and simulation for high-speed coherent optical communication systems, as well as some compensation and equalization algorithms. It mainly consists of the following parts:
1. Analysis of the generation mechanisms and theoretical models of several fiber characteristics are given, including the loss, chromatic dispersion, polarization mode dispersion and nonlinear effects.
2. Detailed analysis of the structure and principle of the coherent receiver system are carried out. Two common receiver solutions, as well as the function and inner structure of each module are introduced. Explanation of modulation and demodulation process is given, and also the implementation principle of polarization division multiplexing. At last, a112Gbit/s PDM-16QAM signal is simulated in a coherent detection system.
3. The description of the structure and principle of the equalizers in the receiver is given, as well as some typical compensating algorithms. For the lack of the conventional constant modulus algorithms, several modified algorithms are developed, and the theoretical models are given, respectively. Then the modified algorithms and the conventional one are simulated in the112Gb/s PDM-16QAM system, including the convergence rate, the convergence effect and the resistance of singularity problem.
4. The necessity of carrier phase recovery is introduced, and the principles of the carrier phase recovery as well as the typical recovery solution are carried out. Then the solution is simulated in the QPSK system. According to the characteristics of16QAM format, an improved scheme is given, and also verified in the PDM-16QAM simulation system. Eventually, the impact of several parameters on the system bit error rate is studied.
In summary, this thesis is mainly about the electrical equalization and compensation in high speed coherent optical communication systems. Based on high-order modulation format as well as the physical model, some modified algorithms and solutions are carried out, in order to improve the transmission efficiency of the system.
引文
[1]T. Richter, E. Palushani, C. Langhorst, et al,. "Single Wavelength Channel 10.2 Tb/s TDM-Data Capacity using 16-QAM and coherent detection", OFC 2011, PDPA9.
[2]A. Sano, T. Kobayashi, S. Yamanaka, et al, "102.3 Tb/s (224*548 Gb/s) C-and L-band All Raman Transmission over 240 km using PDM-64QAM Single Carrier FDM with Pilot Tone," OFC 2012, PDP5C.3.
[3]D. Qian, M. Huang, E. Ip, et al, "101.7-Tb/s (370x294-Gb/s) PDM-128QAM-OFDM Transmission over 3x55-km SSMF using Pilot-based Phase Noise Mitigation", OFC 2011, PDPB5.
[4]J. Yu, Z. Dong, and N. Chi, "Generation, Transmission and Coherent Detection of 11.2 Tb/s (112x100Gb/s) Single Source Optical OFDM Superchannel", OFC 2011.PDPA6.
[5]B. Zhu, T.F. Taunay, M. Fishteyn, et al, "112-Tb/s Space-division multiplexed DWDM transmission with 14-b/s/Hz aggregate spectral efficiency over a 76.8-km seven-core fiber", Opt. Express, vol.19, no.17, pp16665-16671, 2011.
[6]J. Sakaguchi, Y. Awaji, N. Wada, et al, "109-Tb/s (7x97x172-Gb/s SDM/WDM/PDM) QPSK transmission through 16.8-km homogeneous multi-core fiber", OFC 2011, PDPB6.
[7]J. Sakaguchi, B. J. Puttnam, W. Klaus, et al, "19-core fiber transmission of 19 x 100 x 172 Gb/s SDM-WDM-PDM-QPSK signals at 305Tb/s", OFC 2012,PDP5C.l.
[8]M. G. Taylor, "Algorithms for Coherent Detection", OFC 2010,OThL4.
[9]E. Ip, A.P. Lau, et al, "Coherent detection in optical fiber systems", Opt. Express, Vol 16, No.2, pp 753-791,2008.
[10]K. Kikuchi, "Coherent transmission systems", ECOC 2008, Th.2. A.1.
[11]S. J. Savory, "Digital Coherent Optical Receivers:Algorithms and Subsystems", IEEE Journal of Selected Topics in Quantum Electronics, Vol.16, No.5, pp 1164-1179,2010.
[12]D. J. Maylon, T. G. Hodgkinson, D. W. Smith et al., "PSK Homodyne Receiver Sensitivity Measurements at 1.5μm", Electron. Lett., vol.19, no.4, pp.144-146, Feb.1983.
[13]M.J.Adams. An Introduction to Optical Waveguides[M]. Wiley, New York,1981.
[14]A.W.Snyder, J.D.Love. Optical Waveguide Theory[M]. Chapman and Hall, London,1983.
[15]G. P. Agrawal. Applications of Nonlinear Fiber Optics[M]. Second Edition, Elsevier, Singapore,2010.
[16]顾畹仪,李国瑞.光纤通信系统[M].北京邮电大学出版社.2006.
[17]徐霞,席丽霞,张晓光等.光数字相干接收机中色散补偿模块设计与优化[J].光学学报,2011,31(11),pp.1106001.
[18]Q. Yu, A. Shanbhag. Electronic data processing for error and dispersion compensation[J]. Journal of lightwave technology.2006,24(12):4514-4525.
[19]S. J. Savory, G. Gavioli, R. I. Killey, et al,. Electronic compensation of chromatic dispersion using a digital coherent receiver[J]. Optics Express.2007, 15(5):2120-2126.
[20]E. Ip, J. M. Kahn. Digital equalization of chromatic dispersion and polarization mode dispersion[J]. Journal of lightwave technology.2007,25(8):2033-2043.
[21]新谷隆一.偏振光[M].原子能出版社.1994年.
[22]唐先锋.高速光纤通信系统中的集中均衡技术的研究[学位论文].北京邮电大学：2011年.
[23]张晓光.光纤偏振模色散的缓解与补偿技术研究与进展[J].中国激光,36(3),2009,525～539.
[24]张晓光.光纤偏振模色散自适应补偿系统的研究[学位论文].北京邮电大学：2004年.
[25]D. S. Millar, S. Makovejs, C. Behrens, et al,. Mitigation of fiber nonlinearity using a digital coherent receiver[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1217-1226.
[26]L. Du, A. Lowery. Compensating XPM for 100Gb/s coherent channels with 10 Gb/s direct-detection NRZ neighbors[C]. OFC 2010, paper OTuE7.
[27]T. Hoshida, T. Tanimura, S. Oda, et al,. Recent progress on nonlinear compensation technique in digital coherent receiver[C]. OFC 2010, paper OTuE5.
[28]S. Kumar. Analysis of nonlinear phase noise in coherent fiber-optic systems based on phase shift keying[J]. Journal of lightwave technology.2009,27(21): 4722-4733.
[29]K. Kikuchi. Optical Fiber Telecommunications V B:Systems and Networks(Elsevier,2008)
[30]E. Ip, A. P. T. Lau, D. J. F. Barros, et al,. Coherent Detection in Optical Fiber Systems[J]. Optics Express.2008,16(2):753-791.
[31]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[32]M. Seimetz. High-order modulation for optical fiber transmission[M]. Springer-Verlag Berlin Heidelberg 2009.
[33]M. G. Taylor. Algorithms for Coherent Detection[C], OFC 2010, paper OThL4.
[34]S. J. Savory. Digital Coherent Optical Receivers:Algorithms and Subsystems[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010, 16(5):1164-1179.
[35]A. Leven, N. Kaneda, S. Corteselli. Real-time implementation of digital signal processing for coherent optical digital communication systems[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1227-1234.
[36]E. Ip, J. M. Kahn. Digital equalization of chromatic dispersion and polarization mode dispersion[J]. Journal of lightwave technology.2007,25(8):2033-2043.
[37]S. J. Savory, G. Gavioli, R. I. Killey, et al,. Electronic compensation of chromatic dispersion using a digital coherent receiver[J]. Optics Express.2007, 15(5):2120-2126.
[38]Q. Yu, A. Shanbhag. Electronic data processing for error and dispersion compensation[J]. Journal of lightwave technology.2006,24(12):4514-4525.
[39]徐霞,席丽霞,张晓光等.光数字相干接收机中色散补偿模块设计与优化[J].光学学报,2011,31(11),pp.1106001.
[40]冯勇,闻和,张汉一等.差分相移键控信号的数字相干光检测与色散补偿研究与实现[J].中国激光,2010,37(2),pp.471-476.
[41]M. Seimetz. Multi-format transmitters for coherent optical M-PSK and M-QAM Transmission[C]. ICTON 2005, paper Th.B1.5.
[42]M. Seimetz. Performance of coherent optical square-16-QAM-systems based on IQ-transmitters and homodyne receivers with digital phase estimation[C]. OFC 2005, paper NWA4.
[43]许玮.高速光纤通信系统中码型调制技术与偏振模色散补偿技术的研究[学位论文].北京邮电大学：2008年.
[44]邸雪静,童程,张霞等.高速相干光通信系统中的自适应步长恒模算法[J].光学学报,2012,32(10).
[45]I. Fatadin, D. Ives, S. J. Savory. Blind Equalization and Carrier Phase Recovery in a 16-QAM Optical Coherent System[J]. Journal of Lightwave Technology, Aug.2009, vol.27, no.15, pp.3042-3049.
[46]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[47]C. Xie, S. Chandrasekhar. Two-stage Constant Modulus Algorithm Equalizer for Singularity Free Operation and Optical Performance Monitoring in Optical Coherent Receiver[J]. in Proceedings of Optical Fiber Communication Conference,2010,OMK3.
[48]L. Liu, Z. Tao, W. Yan et al., Initial Tap Setup of Constant Modulus Algorithm for Polarization De-multiplexing in Optical Coherent Receivers[J]. in Proceedings of Optical Fiber Communication Conference,2009,OMT2.
[49]K Kikuchi. Polarization-demultiplexing Algorithm in the Digital Coherent Receiver, in IEEE/LEOS Summer Topical Meetings,2008 Digest of the,2008, pp.101-102.
[50]C. Xie, S. Chandrasekhar. Two-stage Constant Modulus Algorithm Equalizer for Singularity Free Operation and Optical Performance Monitoring in Optical Coherent Receiver[J], in Proceedings of Optical Fiber Communication Conference,2010,OMK3.
[51]彭钧,郭见兵,陈东进.一种高阶QAM联合载波恢复算法的研究[J].光通信研究,2011,37(3),pp.20～22.
[52]I. Fatadin, D. Ives, S. J. Savory. Blind Equalization and Carrier Phase Recovery in a 16-QAM Optical Coherent System[J]. Journal of Lightwave Technology, Aug.2009, vol.27, no.15, pp.3042-3049.
[53]S.Abrar, A. K. Nandi. Blind Equalization of Square-QAM Signals:A Multimodulus Approach[J]. IEEE Transactions on Communications, Jun.2010, vol.58, no.6, pp.1674-1685.
[54]C. R. Johnson, Jr., P. Schniter, T. Endres et al., Blind Equalization Using the Constant Modulus Criterion:a review[J]. Proceedings of the IEEE,1998, vol.86, no.10, pp.1927-1950.
[55]D. Godard. Self-recovering Equalization and Carrier Tracking in a Two Dimensional Data Communication System[J]. IEEE Transactions on Communications., Nov.1980, vol.28, no.11, pp.1867-1875.
[56]K Kikuchi. Polarization-demultiplexing Algorithm in the Digital Coherent Receiver, in EEEE/LEOS Summer Topical Meetings,2008 Digest of the,2008, pp.101-102.
[57]V. Zarzoso, P. Comon. Optimal Step-size Constant Modulus Algorithm[J]. IEEE Transactions on Communications, Jan.2008, vol.56, no.1, pp.10-13.
[58]W. Xue, X. Yang, Z. Zhang. A Variable Step Size Blind Equalization Algorithm for QAM signals[J]. in Proceedings of International Conference on Material and Manufacturing Technology,2010, pp.1801-1804.
[59]K. Kikuchi. Optical Fiber Telecommunications V B:Systems and Networks(Elsevier,2008)
[60]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[61]M. G. Taylor. Phase estimation methods for optical coherent detection using digital signal processing[J]. Journal of lightwave technology.2009, 27(7):901-914.
[62]A. P. T. Lau, T. S. R. Shen, W. Shieh, et al,. Equalization-enhanced phase noise for 100Gb/s transmission and beyong with coherent detection[J]. Optics express. 2010,18(16):17239-17251.
[63]J. R. Barry, J. M Kahn. Carrier synchronization for homodyne and heterodyne detection of optical quadriphase-shift keying[J]. IEEE Journal of lightwave technology.1992,10(12):1939-1951.
[64]L. G. Kazovsky. Balance phase-locked loops for optical homodyne receivers: performance analysis and laser linewidth requirements[J]. IEEE Journal of Lightwave Technology.1985,3(6):1238-1247.
[65]R. Noe, S. Hoffman, C. Wordehoff, et al,. Advances in coherent optical modems and 16-QAM transmission with feedforward carrier recovery[C]. SPIE 2011, Vol 7960.
[66]X. Zhou. An improved feedforward carrier recovery algorithm for coherent receivers with M-QAM modulation format[J]. IEEE photonics technology letters. 2010,22(14):1051-1053.
[67]樊弋,张晓光,席丽霞,张文博.16进制正交幅度调制码的相位估计算法的改进[J].光电子激光,2011,12(22).
[68]M. Seimetz. High-order modulation for optical fiber transmission[M]. Springer-Verlag Berlin Heidelberg 2009.
[69]T. Pfau, R. Noe. Phase-noise-tolerant two-stage carrier recovery concept for higher order QAM formats[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1210-1216.
[70]M. Seimetz. Performance of coherent optical square-16-QAM-systems based on IQ-transmitters and homodyne receivers with digital phase estimation[C]. OFC 2005, paper NWA4.
[2]A. Sano, T. Kobayashi, S. Yamanaka, et al, "102.3 Tb/s (224*548 Gb/s) C-and L-band All Raman Transmission over 240 km using PDM-64QAM Single Carrier FDM with Pilot Tone," OFC 2012, PDP5C.3.
[3]D. Qian, M. Huang, E. Ip, et al, "101.7-Tb/s (370x294-Gb/s) PDM-128QAM-OFDM Transmission over 3x55-km SSMF using Pilot-based Phase Noise Mitigation", OFC 2011, PDPB5.
[4]J. Yu, Z. Dong, and N. Chi, "Generation, Transmission and Coherent Detection of 11.2 Tb/s (112x100Gb/s) Single Source Optical OFDM Superchannel", OFC 2011.PDPA6.
[5]B. Zhu, T.F. Taunay, M. Fishteyn, et al, "112-Tb/s Space-division multiplexed DWDM transmission with 14-b/s/Hz aggregate spectral efficiency over a 76.8-km seven-core fiber", Opt. Express, vol.19, no.17, pp16665-16671, 2011.
[6]J. Sakaguchi, Y. Awaji, N. Wada, et al, "109-Tb/s (7x97x172-Gb/s SDM/WDM/PDM) QPSK transmission through 16.8-km homogeneous multi-core fiber", OFC 2011, PDPB6.
[7]J. Sakaguchi, B. J. Puttnam, W. Klaus, et al, "19-core fiber transmission of 19 x 100 x 172 Gb/s SDM-WDM-PDM-QPSK signals at 305Tb/s", OFC 2012,PDP5C.l.
[8]M. G. Taylor, "Algorithms for Coherent Detection", OFC 2010,OThL4.
[9]E. Ip, A.P. Lau, et al, "Coherent detection in optical fiber systems", Opt. Express, Vol 16, No.2, pp 753-791,2008.
[10]K. Kikuchi, "Coherent transmission systems", ECOC 2008, Th.2. A.1.
[11]S. J. Savory, "Digital Coherent Optical Receivers:Algorithms and Subsystems", IEEE Journal of Selected Topics in Quantum Electronics, Vol.16, No.5, pp 1164-1179,2010.
[12]D. J. Maylon, T. G. Hodgkinson, D. W. Smith et al., "PSK Homodyne Receiver Sensitivity Measurements at 1.5μm", Electron. Lett., vol.19, no.4, pp.144-146, Feb.1983.
[13]M.J.Adams. An Introduction to Optical Waveguides[M]. Wiley, New York,1981.
[14]A.W.Snyder, J.D.Love. Optical Waveguide Theory[M]. Chapman and Hall, London,1983.
[15]G. P. Agrawal. Applications of Nonlinear Fiber Optics[M]. Second Edition, Elsevier, Singapore,2010.
[16]顾畹仪,李国瑞.光纤通信系统[M].北京邮电大学出版社.2006.
[17]徐霞,席丽霞,张晓光等.光数字相干接收机中色散补偿模块设计与优化[J].光学学报,2011,31(11),pp.1106001.
[18]Q. Yu, A. Shanbhag. Electronic data processing for error and dispersion compensation[J]. Journal of lightwave technology.2006,24(12):4514-4525.
[19]S. J. Savory, G. Gavioli, R. I. Killey, et al,. Electronic compensation of chromatic dispersion using a digital coherent receiver[J]. Optics Express.2007, 15(5):2120-2126.
[20]E. Ip, J. M. Kahn. Digital equalization of chromatic dispersion and polarization mode dispersion[J]. Journal of lightwave technology.2007,25(8):2033-2043.
[21]新谷隆一.偏振光[M].原子能出版社.1994年.
[22]唐先锋.高速光纤通信系统中的集中均衡技术的研究[学位论文].北京邮电大学：2011年.
[23]张晓光.光纤偏振模色散的缓解与补偿技术研究与进展[J].中国激光,36(3),2009,525～539.
[24]张晓光.光纤偏振模色散自适应补偿系统的研究[学位论文].北京邮电大学：2004年.
[25]D. S. Millar, S. Makovejs, C. Behrens, et al,. Mitigation of fiber nonlinearity using a digital coherent receiver[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1217-1226.
[26]L. Du, A. Lowery. Compensating XPM for 100Gb/s coherent channels with 10 Gb/s direct-detection NRZ neighbors[C]. OFC 2010, paper OTuE7.
[27]T. Hoshida, T. Tanimura, S. Oda, et al,. Recent progress on nonlinear compensation technique in digital coherent receiver[C]. OFC 2010, paper OTuE5.
[28]S. Kumar. Analysis of nonlinear phase noise in coherent fiber-optic systems based on phase shift keying[J]. Journal of lightwave technology.2009,27(21): 4722-4733.
[29]K. Kikuchi. Optical Fiber Telecommunications V B:Systems and Networks(Elsevier,2008)
[30]E. Ip, A. P. T. Lau, D. J. F. Barros, et al,. Coherent Detection in Optical Fiber Systems[J]. Optics Express.2008,16(2):753-791.
[31]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[32]M. Seimetz. High-order modulation for optical fiber transmission[M]. Springer-Verlag Berlin Heidelberg 2009.
[33]M. G. Taylor. Algorithms for Coherent Detection[C], OFC 2010, paper OThL4.
[34]S. J. Savory. Digital Coherent Optical Receivers:Algorithms and Subsystems[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010, 16(5):1164-1179.
[35]A. Leven, N. Kaneda, S. Corteselli. Real-time implementation of digital signal processing for coherent optical digital communication systems[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1227-1234.
[36]E. Ip, J. M. Kahn. Digital equalization of chromatic dispersion and polarization mode dispersion[J]. Journal of lightwave technology.2007,25(8):2033-2043.
[37]S. J. Savory, G. Gavioli, R. I. Killey, et al,. Electronic compensation of chromatic dispersion using a digital coherent receiver[J]. Optics Express.2007, 15(5):2120-2126.
[38]Q. Yu, A. Shanbhag. Electronic data processing for error and dispersion compensation[J]. Journal of lightwave technology.2006,24(12):4514-4525.
[39]徐霞,席丽霞,张晓光等.光数字相干接收机中色散补偿模块设计与优化[J].光学学报,2011,31(11),pp.1106001.
[40]冯勇,闻和,张汉一等.差分相移键控信号的数字相干光检测与色散补偿研究与实现[J].中国激光,2010,37(2),pp.471-476.
[41]M. Seimetz. Multi-format transmitters for coherent optical M-PSK and M-QAM Transmission[C]. ICTON 2005, paper Th.B1.5.
[42]M. Seimetz. Performance of coherent optical square-16-QAM-systems based on IQ-transmitters and homodyne receivers with digital phase estimation[C]. OFC 2005, paper NWA4.
[43]许玮.高速光纤通信系统中码型调制技术与偏振模色散补偿技术的研究[学位论文].北京邮电大学：2008年.
[44]邸雪静,童程,张霞等.高速相干光通信系统中的自适应步长恒模算法[J].光学学报,2012,32(10).
[45]I. Fatadin, D. Ives, S. J. Savory. Blind Equalization and Carrier Phase Recovery in a 16-QAM Optical Coherent System[J]. Journal of Lightwave Technology, Aug.2009, vol.27, no.15, pp.3042-3049.
[46]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[47]C. Xie, S. Chandrasekhar. Two-stage Constant Modulus Algorithm Equalizer for Singularity Free Operation and Optical Performance Monitoring in Optical Coherent Receiver[J]. in Proceedings of Optical Fiber Communication Conference,2010,OMK3.
[48]L. Liu, Z. Tao, W. Yan et al., Initial Tap Setup of Constant Modulus Algorithm for Polarization De-multiplexing in Optical Coherent Receivers[J]. in Proceedings of Optical Fiber Communication Conference,2009,OMT2.
[49]K Kikuchi. Polarization-demultiplexing Algorithm in the Digital Coherent Receiver, in IEEE/LEOS Summer Topical Meetings,2008 Digest of the,2008, pp.101-102.
[50]C. Xie, S. Chandrasekhar. Two-stage Constant Modulus Algorithm Equalizer for Singularity Free Operation and Optical Performance Monitoring in Optical Coherent Receiver[J], in Proceedings of Optical Fiber Communication Conference,2010,OMK3.
[51]彭钧,郭见兵,陈东进.一种高阶QAM联合载波恢复算法的研究[J].光通信研究,2011,37(3),pp.20～22.
[52]I. Fatadin, D. Ives, S. J. Savory. Blind Equalization and Carrier Phase Recovery in a 16-QAM Optical Coherent System[J]. Journal of Lightwave Technology, Aug.2009, vol.27, no.15, pp.3042-3049.
[53]S.Abrar, A. K. Nandi. Blind Equalization of Square-QAM Signals:A Multimodulus Approach[J]. IEEE Transactions on Communications, Jun.2010, vol.58, no.6, pp.1674-1685.
[54]C. R. Johnson, Jr., P. Schniter, T. Endres et al., Blind Equalization Using the Constant Modulus Criterion:a review[J]. Proceedings of the IEEE,1998, vol.86, no.10, pp.1927-1950.
[55]D. Godard. Self-recovering Equalization and Carrier Tracking in a Two Dimensional Data Communication System[J]. IEEE Transactions on Communications., Nov.1980, vol.28, no.11, pp.1867-1875.
[56]K Kikuchi. Polarization-demultiplexing Algorithm in the Digital Coherent Receiver, in EEEE/LEOS Summer Topical Meetings,2008 Digest of the,2008, pp.101-102.
[57]V. Zarzoso, P. Comon. Optimal Step-size Constant Modulus Algorithm[J]. IEEE Transactions on Communications, Jan.2008, vol.56, no.1, pp.10-13.
[58]W. Xue, X. Yang, Z. Zhang. A Variable Step Size Blind Equalization Algorithm for QAM signals[J]. in Proceedings of International Conference on Material and Manufacturing Technology,2010, pp.1801-1804.
[59]K. Kikuchi. Optical Fiber Telecommunications V B:Systems and Networks(Elsevier,2008)
[60]K. Kikuchi. Coherent transmission systems[C]. ECOC 2008, paper Th.2.A.1.
[61]M. G. Taylor. Phase estimation methods for optical coherent detection using digital signal processing[J]. Journal of lightwave technology.2009, 27(7):901-914.
[62]A. P. T. Lau, T. S. R. Shen, W. Shieh, et al,. Equalization-enhanced phase noise for 100Gb/s transmission and beyong with coherent detection[J]. Optics express. 2010,18(16):17239-17251.
[63]J. R. Barry, J. M Kahn. Carrier synchronization for homodyne and heterodyne detection of optical quadriphase-shift keying[J]. IEEE Journal of lightwave technology.1992,10(12):1939-1951.
[64]L. G. Kazovsky. Balance phase-locked loops for optical homodyne receivers: performance analysis and laser linewidth requirements[J]. IEEE Journal of Lightwave Technology.1985,3(6):1238-1247.
[65]R. Noe, S. Hoffman, C. Wordehoff, et al,. Advances in coherent optical modems and 16-QAM transmission with feedforward carrier recovery[C]. SPIE 2011, Vol 7960.
[66]X. Zhou. An improved feedforward carrier recovery algorithm for coherent receivers with M-QAM modulation format[J]. IEEE photonics technology letters. 2010,22(14):1051-1053.
[67]樊弋,张晓光,席丽霞,张文博.16进制正交幅度调制码的相位估计算法的改进[J].光电子激光,2011,12(22).
[68]M. Seimetz. High-order modulation for optical fiber transmission[M]. Springer-Verlag Berlin Heidelberg 2009.
[69]T. Pfau, R. Noe. Phase-noise-tolerant two-stage carrier recovery concept for higher order QAM formats[J]. IEEE Journal of Selected Topics in Quantum Electronics.2010,16(5):1210-1216.
[70]M. Seimetz. Performance of coherent optical square-16-QAM-systems based on IQ-transmitters and homodyne receivers with digital phase estimation[C]. OFC 2005, paper NWA4.