基于光正交频分复用的光与无线融合接入技术研究
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摘要
随着网络的发展和通信需求的提高,未来的接入网不仅需要满足用户的高带宽需求,而且需要给用户提供灵活多样的接入方式(高速有线接入和灵活的宽带无线接入)。在无源光接入网(PON)中同时传输无线和有线的信号,可以将无线接入的灵活性和有线接入的大容量和高稳定性相结合,提高服务的综合性,具有很高的研究价值。但是,现有的PON与移动网络融合接入存在带宽容量不足、系统结构复杂、带宽资源分配冲突等问题。为解决以上问题,本论文提出基于光正交频分复用(OFDM)的PON与无线接入信号(LTE, WiFi和60GHz-ROF)的异构融合接入模型,实现光与无线的异构融合接入。目前该技术的研究还有难点需要克服：如,下行融合信号的生成及交调干扰的抑制；光OFDM信号的高峰均比(PAPR)抑制和融合信号在光纤中传输时色散效应和噪声影响的消除问题等。从解决以上问题的角度出发,本论文围绕基于光OFDM的光与无线异构融合接入技术展开深入研究,具体工作和创新如下：
1)对OFDM-PON技术展开深入研究。分别构建了时分复用(TDM)和波分复用(WDM)与OFDM-PON的混合接入系统架构模型,并进行了性能分析和网络资源分配方式的研究；采用理论分析、仿真计算和实验研究相结合的方法研究了基于外调制的OFDM-PON系统的性能；研究了OFDM-PON的下行载波重利用技术,节省上行传输所需激光光源,最大限度简化用户端结构的同时实现全双工通信。
2)论文提出了基于光OFDM的PON与无线接入主流信号LTE, WiFi和60GHz-ROF的异构融合接入模型,使得不同接入方式的接入信号同时在光纤中传输,实现光与无线的异构融合接入：对于OFDM-PON与LTE和WiFi的异构融合模型,论文提出采用中频混频技术使得无线信号的工作频带与有线信号的传输频带远离布里渊散射等非线性效应的易发条件,抑制接收端光电转换时的交调干扰；对于OFDM-PON与60GHz-ROF的信号融合模型,论文提出采用马赫曾德光调制器组结合光学外调制技术生成融合下行信号,简化系统结构,实现光与无线的融合接入。设计生成的有线／无线融合信号通过光调制器调制到光域生成下行光信号,论文对基于马赫曾德调制器的多业务信号调制机制进行了数学建模和分析,优化选用合适的调制深度,使融合信号工作在调制器的线性区域,有效抑制了下行光信号中的无用边带。
3)针对光OFDM系统中的高峰均比(PAPR)抑制问题,本论文提出采用压扩参数可控的双曲正切函数对信号进行压扩处理。算法在双曲正切函数中引入两个可控参数,分别控制压扩信号的最大压缩幅值和压扩的非线性程度,使得小信号得到放大,大信号得到压缩,从而有效降低信号的PAPR。仿真结果显示所提算法对PAPR的抑制作用和误码率性能都优于μ律。
4)针对光OFDM接入系统中的信道估计问题,本论文提出了一种基于导频的信道估计算法。算法只在光OFDM信号的前半部分子载波中插入导频,利用后补偿的方法结合光纤信道色散效应与子载波频率的对应关系,最终实现了导频数目少,计算复杂度低的信道估计,有效抵抗了传输中色散和相位噪声的影响。相关的性能仿真结果显示,实现了40Gb/s的下行信号接入,且所提算法的误码率性能要高于其他基于LS准则的信道估计算法。
本论文从网络架构模型和性能提升算法的角度出发,采用数学建模、仿真计算以及实验研究相结合的方法对基于光OFDM的光与无线融合接入技术展开研究。以上所提技术可简化远端用户接收结构,降低系统成本,提高系统传输性能和频谱效率,增大系统覆盖区域和接入方式的灵活性,最终实现光与无线异构融合的泛在信息接入。
With the increasing demand of the communication bandwidth, the future access network should provide not only enough bandwidth, but also various access methods (wired and wireless access). It is significant to research on the heterogeneous integration access technique of passive optical network (PON) and wireless communications which can combine the flexible mobility of the wireless communications and the high-capacity of the wired communication. However, there are some drawbacks in the existing integration network, such as, deficient bandwidth, complexity system structure, and bandwidth distribution conflict. Based on the study of orthogonal frequency division multiplexing (OFDM), novel PON architecture which can simultaneously support various services, such as LTE, wifi and60GHz-radio-over-fiber (ROF) is proposed in this dissertation. However, there are still some challenges, such as, bandwidth distribution scheme, high peak to average power ratio (PAPR) suppression and channel estimation. In order to solve those problems, in-depth research about the heterogeneous integration access technique of optical wired/wireless services based on optical OFDM are made in this dissertation. The detailed works are as follows:
(1) Some in-depth studies of the time division multiplexing OFDM-PON and wavelength division multiplexing OFDM-PON, which include system models, performance analysis and network resource allocation, are done with the combined method of theoretical analysis, simulation and experiment. Downlink carrier re-use technology is researched to save the uplink light source and simplify the ONU structure.
(2) Based on the above study of OFDM-PON, novel PON architecture which can simultaneously support heterogeneous services such as PON, LTE, WiFi and60GHz-ROF is presented. Intermedium frequency (IF) mixing technology is utilized to make the operation band of OFDM-PON, LTE and WiFi away from the Brillouin scattering effects. Meanwhile, a Mach Zehnder modulator (MZM) group combined with the optical external modulation technique are applied to generate high-quality downlink OFDM-PON-ROF integration signals. The generated wired/wireless heterogeneous signals are modulated into optical domain through optical modulator. In order to generate high quality heterogeneous signals which have no useless signal-band, the mathematical model of MZM is analyzed. Then, suitable modulation depth which could make the integration signals work in the linear region of the optical modulator and reduce the useless signal-band in the downstream signal highly, is optimized.
(3) Now, how to suppress the PAPR in optical OFDM access system is still a challenge. Nonlinear companding transform is an effective technique to reduce the PAPR in optical OFDM transmission system. A novel companding scheme, which is based on the modified hyperbolic tangent (MHT) transform, is presented in this dissertation. The MHT scheme can enlarge the small signals and compress the large signals while keeping the average power invariant through two companding parameters. Numerical mathematical models of PAPR have been analyzed. Simulation results show that large PAPR reduction was achieved and offered better bit error rate (BER) performance than the famous μ law.
(4) Inspired by nonlinear post-compensation algorithms, a channel estimation algorithm which can highly resist dispersion and phase noise in the optical OFDM system is presented. The proposed scheme is pilot-aided in which just a little number of pilots is inserted in the first half part of the subcarriers and high spectral efficiency is achieved. The fiber dispersion and the phase noise are resisted with the combined method of post-compensation and the relationship between the OFDM subcarriers and the fiber channel mathematic model. Numerical mathematic models have been analyzed. Simulation results show that the presented scheme achieved40Gbit/s data transmission and the BER performance of the proposed algorithm is better than other LS channel estimation algorithms.
This dissertation focuss on the heterogeneous intergration access of optical wired/wireless services with the combining method of mathematic model analysis, simulation and experiment.Those above research technologies can highly simplify the remote receiving structure, reduce the cost of transmission, improve the access flexibility and achieve ubiquitous information access. The research in this dissertation will play an important role in the next generation information highway.
1)对OFDM-PON技术展开深入研究。分别构建了时分复用(TDM)和波分复用(WDM)与OFDM-PON的混合接入系统架构模型,并进行了性能分析和网络资源分配方式的研究；采用理论分析、仿真计算和实验研究相结合的方法研究了基于外调制的OFDM-PON系统的性能；研究了OFDM-PON的下行载波重利用技术,节省上行传输所需激光光源,最大限度简化用户端结构的同时实现全双工通信。
2)论文提出了基于光OFDM的PON与无线接入主流信号LTE, WiFi和60GHz-ROF的异构融合接入模型,使得不同接入方式的接入信号同时在光纤中传输,实现光与无线的异构融合接入：对于OFDM-PON与LTE和WiFi的异构融合模型,论文提出采用中频混频技术使得无线信号的工作频带与有线信号的传输频带远离布里渊散射等非线性效应的易发条件,抑制接收端光电转换时的交调干扰；对于OFDM-PON与60GHz-ROF的信号融合模型,论文提出采用马赫曾德光调制器组结合光学外调制技术生成融合下行信号,简化系统结构,实现光与无线的融合接入。设计生成的有线／无线融合信号通过光调制器调制到光域生成下行光信号,论文对基于马赫曾德调制器的多业务信号调制机制进行了数学建模和分析,优化选用合适的调制深度,使融合信号工作在调制器的线性区域,有效抑制了下行光信号中的无用边带。
3)针对光OFDM系统中的高峰均比(PAPR)抑制问题,本论文提出采用压扩参数可控的双曲正切函数对信号进行压扩处理。算法在双曲正切函数中引入两个可控参数,分别控制压扩信号的最大压缩幅值和压扩的非线性程度,使得小信号得到放大,大信号得到压缩,从而有效降低信号的PAPR。仿真结果显示所提算法对PAPR的抑制作用和误码率性能都优于μ律。
4)针对光OFDM接入系统中的信道估计问题,本论文提出了一种基于导频的信道估计算法。算法只在光OFDM信号的前半部分子载波中插入导频,利用后补偿的方法结合光纤信道色散效应与子载波频率的对应关系,最终实现了导频数目少,计算复杂度低的信道估计,有效抵抗了传输中色散和相位噪声的影响。相关的性能仿真结果显示,实现了40Gb/s的下行信号接入,且所提算法的误码率性能要高于其他基于LS准则的信道估计算法。
本论文从网络架构模型和性能提升算法的角度出发,采用数学建模、仿真计算以及实验研究相结合的方法对基于光OFDM的光与无线融合接入技术展开研究。以上所提技术可简化远端用户接收结构,降低系统成本,提高系统传输性能和频谱效率,增大系统覆盖区域和接入方式的灵活性,最终实现光与无线异构融合的泛在信息接入。
With the increasing demand of the communication bandwidth, the future access network should provide not only enough bandwidth, but also various access methods (wired and wireless access). It is significant to research on the heterogeneous integration access technique of passive optical network (PON) and wireless communications which can combine the flexible mobility of the wireless communications and the high-capacity of the wired communication. However, there are some drawbacks in the existing integration network, such as, deficient bandwidth, complexity system structure, and bandwidth distribution conflict. Based on the study of orthogonal frequency division multiplexing (OFDM), novel PON architecture which can simultaneously support various services, such as LTE, wifi and60GHz-radio-over-fiber (ROF) is proposed in this dissertation. However, there are still some challenges, such as, bandwidth distribution scheme, high peak to average power ratio (PAPR) suppression and channel estimation. In order to solve those problems, in-depth research about the heterogeneous integration access technique of optical wired/wireless services based on optical OFDM are made in this dissertation. The detailed works are as follows:
(1) Some in-depth studies of the time division multiplexing OFDM-PON and wavelength division multiplexing OFDM-PON, which include system models, performance analysis and network resource allocation, are done with the combined method of theoretical analysis, simulation and experiment. Downlink carrier re-use technology is researched to save the uplink light source and simplify the ONU structure.
(2) Based on the above study of OFDM-PON, novel PON architecture which can simultaneously support heterogeneous services such as PON, LTE, WiFi and60GHz-ROF is presented. Intermedium frequency (IF) mixing technology is utilized to make the operation band of OFDM-PON, LTE and WiFi away from the Brillouin scattering effects. Meanwhile, a Mach Zehnder modulator (MZM) group combined with the optical external modulation technique are applied to generate high-quality downlink OFDM-PON-ROF integration signals. The generated wired/wireless heterogeneous signals are modulated into optical domain through optical modulator. In order to generate high quality heterogeneous signals which have no useless signal-band, the mathematical model of MZM is analyzed. Then, suitable modulation depth which could make the integration signals work in the linear region of the optical modulator and reduce the useless signal-band in the downstream signal highly, is optimized.
(3) Now, how to suppress the PAPR in optical OFDM access system is still a challenge. Nonlinear companding transform is an effective technique to reduce the PAPR in optical OFDM transmission system. A novel companding scheme, which is based on the modified hyperbolic tangent (MHT) transform, is presented in this dissertation. The MHT scheme can enlarge the small signals and compress the large signals while keeping the average power invariant through two companding parameters. Numerical mathematical models of PAPR have been analyzed. Simulation results show that large PAPR reduction was achieved and offered better bit error rate (BER) performance than the famous μ law.
(4) Inspired by nonlinear post-compensation algorithms, a channel estimation algorithm which can highly resist dispersion and phase noise in the optical OFDM system is presented. The proposed scheme is pilot-aided in which just a little number of pilots is inserted in the first half part of the subcarriers and high spectral efficiency is achieved. The fiber dispersion and the phase noise are resisted with the combined method of post-compensation and the relationship between the OFDM subcarriers and the fiber channel mathematic model. Numerical mathematic models have been analyzed. Simulation results show that the presented scheme achieved40Gbit/s data transmission and the BER performance of the proposed algorithm is better than other LS channel estimation algorithms.
This dissertation focuss on the heterogeneous intergration access of optical wired/wireless services with the combining method of mathematic model analysis, simulation and experiment.Those above research technologies can highly simplify the remote receiving structure, reduce the cost of transmission, improve the access flexibility and achieve ubiquitous information access. The research in this dissertation will play an important role in the next generation information highway.
引文
[1]Kao KC, Hockman GA. Dielectric-fiber surface waveguides for optical frequencies [J]. Porc.IEEE 1966,113(7):1151-8.
[2]顾畹仪,李国瑞.光纤通信系统[M].北京：北京邮电大学出版社,2006.209-210.
[3]陈雪.无源光网络技术[M].北京：北京邮电大学出版社,2006.1-12.
[4]internet world stats-www.internetworldstats.com/stats.htm
[5]http://www.ciscovni.com/vni_forecast/advanced.html
[6]韦乐平.光网络的发展趋势与挑战[J].电信科学,201 1,27(2):10-14.
[7]Sano A, Yamada E, Masuda H, et al.13.4-Tb/s(134×111-Gb/s/ch)no-guard-interval coherent OFDM transmission over 3600km of SMF with 19-ps average PMD[A]. In:Proceeding of the Eur.Conf. of optical communications[C].Brussels Belgium:2008.Th.3.E.1.
[8]R.Berezdivin, R.Breinig, and R.Topp, Next-generation wireless communications concepts and technologies [J]. IEEE communications magazine,2002,40:108-116.
[9]3GPP TS 36.101,3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA);User Equipment (UE) radio transmission and reception[S].Realse 11.
[10]马修.贝科,LTE-UMTS长期演进理论与实践,北京：人民邮电出版社,2009,12。
[11]IEEE 802.11a-1999 (8802-11:1999/Amd 1:2000(E)),Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications-Amendment 1:High-speed PhysicalLayer in the 5GHzband[S].1999.
[12]IEEE 802.11b-1999 Supplement to 802.11-1999, Wireless LAN MAC and PHY specifications: Higher speed Physical Layer (PHY) extension in the 2.4GHzband[S].1999.
[13]IEEE 802.11e-2005, Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications:Amendment 8:Medium Access Control (MAC) Quality of Service Enhancements[S].2005.
[14]Youngsu Cho, Myungin Ji and Yangkoo Lee, et al WIFI AP position estimation using contribution from heterogeneous mobile devices[A]. In:Proceeding of the IEEE position location and navigation symposium[C].Myrtle Beach SC:2012.562-567.
[15]Pareit Daan, Lannoo Bart and Moerman Ingrid, et al. The History of WiMAX:A Complete Survey of the Evolution in Certification and Standardization for IEEE 802.16 and WiMAX [J]. IEEE communications survey & Tutorials,2011,14(4):1183-1121.
[16]ITU-T G.995.1. Overview for digital subscriber line (DSL) recommendations[S].2001.
[17]YD/T 1063-2000.接入网技术要求-混合光纤同轴电缆网(HFC)[S].2000.
[18JITU-T G.983.1. Broadband optical access systems based on passive optical network (PON) [S].1998
[19]Cedric Lam, Passive Optical Networks [M]. Burlington USA:Academic Press in an imprint of elsevier,2007.19-29.
[20]Kamal A.E., Blietz B.F. A priority mechanism for the IEEE 802.3ah EPON [A]. In: Proceeding of the IEEE international conference on communications[C].2005:1879-1883.
[21]Kramer G., Mukherjee B., and Pessavento G. Ipact:a dynamic protocol for an Ethernet PON [J]. IEEE communication Magazine,2002,40(2):74-80.
[22]Vica Cale. Gigabit passive optical network-GPON [A].In:Proceeding of the ITI 200729th Int. Conf. on information technology interfaces[C]. Cavtat Croatia:2007.679-684.
[23]Shieh W, Athaudage C, Coherent optical orthogonal frequency division multiplexing [J]. Electronics Letters,2006,42(10):1-2.
[24]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express. 2008.16(2):841-859.
[25]Hung-Chang Chien,Ming-Fang Huang,Jie Liu,et al. Novel Architectures for Orthogonal Wavelength Division Multiplexed Passive Optical Networks (OFDM-PONs) in a 25-GHz Grid[A]. In:Proceeding of the 2011 optical fiber communication conference and exposition (OFC) [C].Los Angles:2011.OTuB6.
[26]Jun-ichi Kani, Naoto Yoshimoto, Next generation PONs:an operator's view[A]. In: Proceedings of the European Conference on Optical Communications (ECOC)[C]. Austria:2009.5.7.4.
[27]Sander L. Jansen, Itsuro Morita, Kamyar Forozesh, and et al. Optical OFDM, a hype or is it for real?[A].In:Proceedings of the 2008 European Conference on Optical Communications (ECOC) [C].Burssels:2008.49-52.
[28]C. H. Wang, C. W. Chow, C. H. Yeh, et al. Demonstration of Hybrid 10Gb/s PON and 10Gb/s OFDM-ROF Architecture Towards Next Generation Access Networks[J].SPIE-OSA-IEEE Asia Communications and Photonics,2009,7632(2):1-6.
[29]P. Chanclou, F.Bourgart and B.Landousies, et al. Technical options for NGPON2 beyond 10G PON [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C]. Geneva:2011.We.9.C.3.
[30]Ning C.Passive Optical Networks for Mobile Backhaul [A].In:Proceeding of the workshop on Photonic Technologies for Access and Bio-Photonics [C].Dusseldorf Germanny:2011.
[31]Helmy A., Fathallah H., and Mouftah H.. Interleaved polling versus multi-thread polling for bandwidth allocation in long-reach PONs [J]. IEEE/OS A Journal of Optical Communications and Networking,2012,4(3):210-218.
[32]Dayou Qian, Neda Cvijetic, and Junqiang Hu, et al. A novel OFDMA-PON architecture with source-freee ONUs for next-generation optical access networks[J]. IEEE photonics technology letters,2009,21 (17):1265-1267.
[33]Dayou Qian, Junqiang Hu, and Philip Nan Ji, et al. 10Gb/s OFDMA-PON for delivery of heterogeneous services[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C]. San Diego CA:2008.OWH4.
[34]Lei Xu, Dayou Qian and Junqiang Hu, et al. OFDMA-based passive optical networks[A].In: Proceeding of the IEEE summer topical meeting[C]. Acapulco:2008.TuE3.1.
[35]Maria Morant,Terence Quinlan, Roberto Liorente,et al. Full Standard Triple-Play Bi-Directional and Full-Duplex CWDM Transmission in Passive Optical Network[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angles CA:2011.OWB3.
[36]Maria Morant, Terence Quinlan, Stuart Walker, et al.Complete Mitigation of Brillouin Scattering Effects in Reflective Passive Optical Networks using Triple-Format OFDM Radio Signals[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angles CA:2011.JWA72.
[37]Filipe Carvalho, Adolfo Cartaxo.Baseband OFDM and ultrawide band OFDM signals coexistence requirements for extended rach PONs[A]. In:Proceeding of the 12th international conference on transparent optical networks ICTON2010[C]. Munich:2010.Th.A2.6.
[38]Filipe Carvalho, Adolfo Cartaxo.Power requirements for coexisting baseband and wireless OFDM-based signals in hybrid metro-access networks[A]. In:Proceeding of the 13th international conference on transparent optical networks (ICTON) 2011[C].Stockholm: 2011.Tu.A5.6.
[39]J.Armstrong, Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J].Electronics letters,2002,38(5):246-247.
[40]Omer Bulakci, Matthias Schuster, Christian-A. Bunge, et al., Reduced Complexity Precoding Based Peak-to-Average Power Ratio Reduction Applied to Optical Direct-Detection OFDM [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Brussels, Belgium:2008.P.4.11.
[41]Shieh, W., Tucher Rodney S., and Chen Wei, et al. Optical Performance Monitoring through Channel Estimation by Receiver Signal Processing[A].In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Cannes France:2006.1-2.
[1]王文博,郑侃,宽带无线通信OFDM技术[M].北京：人民邮电出版社,2003.2-10.
[2]Chang RW. Synthesis of band-limited orthogonal signals for multichannel data transmission [J], Bell System Technology Journal,1966,45:1775-1796.
[3]Jun-ichi Kani, Naoto Yoshimoto, Next generation PONs:an operator's view[A], In:Proceedings of the European Conference on Optical Communications (ECOC) [C], Austria:2009.5.7.4.
[4]Hiroshi Ichibangase and Kuniaki Motoshima, Next generation optical transport technology [J], Mitsubishi electric advance,2008:6-9.
[5]William Shieh, Ivan Djordjevic, Orthogonal frequency division multiplexing for optical communications [M], Burlington USA:Academic press of Elsevier,2010.22-24.
[6]Weinsten SB, Ebert PM. Data transmission by frequency-dvision multiplexing using the discrete Fourier transform[J], IEEE Trans Commun,1997,19:628-634.
[7]Duhamel P, Hollmann H. Split-radix FFT algorithm[J]. IET electronic letter,1984,20:14-16.
[8]Hara S, Prasad R. Multicarrier techniques for 4G mobile communicationsfM], Boston:Arrech House,2003.33-39.
[9]Armstrong J., Tutorial on optical OFDM [A], In:Proceeding of the 2012 14th international conference on transparent optical networks (ICTON) [C], Coventry United Kingdom:2012.1.
[10]Armstrong J., OFDM for optical communications [J] Journal of lightwave technology,2009, 27(3):189-204.
[11]Dayou Qian, Neda Cvijetic and Junqiang Hu, et al. Optical OFDM transmission in metro/access networks [A], In:Proceeding of the OFC 2009[C],San Diego:2009.OMV1.
[12]Zheng Z.H., Qian Zongjue and Shou G.C., Next-generation passive optical network based on OFDM transmission [A], In:Proceeding of the 2009 WASE international conference on information engineering[C],Taiyuan:2009.329-332.
[13]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express. 2008.16(2):841-859.
[14]Yan Tang, Shieh W.. Coherent optical OFDM transmission up to lTb/s per channel[J]Journal of lightwave technology,2009,27(16):3511-3517.
[15]W.Shieh, X.Yi and Y.Tang. Transmission experiment of multi-gigabit coherent optical OFDM systems over 1000km SSMF fiber [J].Electronics letters,2007,43(3):183-184
[16]W. Shieh and C.Athaudage, Coherent optical orthogonal frequency division multiplexing [J]. Electronics letters,2006,42(10):587-589.
[17]Arthur James Lowery, Liang Bangyuan Du, and Jean Armstrong. Performance of optical OFDM in ultralong-haul WDM lightwave systems [J]. Journal of lightwave technology, 2007,25(1):131-138.
[18]Xuejun Liu, Yaojun Qiao and Yuefeng Ji. electronic compensator for 100G-b/s PDM-CO-OFDM long-hual transmission systems[J]. Chinese optics letters, 2011,9(3):030602-1-5.
[19]Sander L.Jansen, Itsuro Morita and Kamyar Forozesh, et al. Optical OFDM, a hype or is it for real?[A]. In:Proceeding of the 34th Eruropean conference on optical communication[C]. Brussels Belgium:2008.Mo.3.E.3.
[20]Ghislain Mouil Sil, Hadrien Louchet and Andre Richter. Efficient BER estimation for radio-over-fiber systems[A].In:Proceeding of the conference on optical fiber communication and the national fiber optic engineers conference[C], Anaheim CA:2007.1-3.
[21]Rishad Ahmed Shafik Md.Shahriar Rahman and AHM Razibul Islam. On the extended relationship among EVM, BER and SNR as performance metrics [A]. In:Proceeding of the 4th international conference on electrical and computer engineering ICECE[C]. Dhaka Bangladesh:2006.408-411.
[22]Rene-jean Essiambre, Gerard J.Foschini and Peter J.Winzer, et al. The capacity of fiber-optic communication systems[A].In:Proceeding of the conference on optical fiber communication/National fiber optic engineers conference[C].San Diego CA:2008.1-3.
[23]Rene-jean Essiambre, Gerard J.Foschini and Peter J.Winzer, et al. Capacity limits of optical fiber networks [J]. Journal of lightwave technology,2010,28(4):662-701.
[24]John G.Proakis, Masoud Salehi, Gerhard Bauch, Contemporary communications systems using matlab [M],2nd edition, Nelson Engineering,2003.
[25]Hussin S., Puntsri K., Noe R.. Performance analysis of optical OFDM systems [A].In:Proceeding of the 2011 3rd international congress on ultra modern telecommunications and control systems and workshops[C].Budapest:2011.1-5.
[26]Djordjevic IB, Vasic B.Orthogonal frequency division multiplexing for high-speed optical transmission[J].Optics express,2007,15(10):6332-6346.
[27]Berrou C, Glavieux A.Thitimajshima P. Near Shannon limit error-correcting coding and decoding:Turbo codes[A]. In:Proceeding of the 1993 Int. Conf. of Communications[C]. Geneva Swetzerland:1993.1064-1070.
[28]Seung H.H., Jae H.L., An overview of peak-to-average power ratio reduction techniques for multicarrier transmission [J]. IEEE Wireless Communications,2005,12(2):56-65.
[29]J.armstrong. Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J]. Electronics Letters,2002,38(5):246-247.
[30]Yuki Yoshida, Akihiro Maruta and Ken-ichi Kitayama. On the peak-to-average power ratio distribution along fiber in the optical OFDM transmissions [A]. In:Proceeding of the European Conference on Optical Communications[C], Gneva:2011.We.10.P1.69.
[31]Morelli, M. and U. Mengali. A comparison of pilot-aided channel estimation methods for OFDM systems [J], IEEE Transactions on Signal Processing.2001.49(12):3065-3073.
[32]W.Shieh, Maximum-likelihood phase and channel estimation for coherent optical OFDM[J].IEEEE photonics technology letters.2008.20(8):605-607.
[33]Mingying, L., Song Yu and Wanyi Gu, et al. A LMMSE channel estimator for coherent optical OFDM system [A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP) [C]. Shanghai, China:2009.1-2.
[34]Xiaoyong Hao, Kun Qiu, Chongfu Zhang,et al.On the Timing Synchronization Methods for Optical Orthogonal Frequency Division Multiplexing (O-OFDM) Systems:Comparisons and Improvement[A].In:Proceeding of the 2009 Asia communications and photonics conference and exhibition (OSA/ACP)[C].Shanghai China:2009.Th04.
[35]Wang Zhuo, Wu Dapeng, Liu Zuqi, Wang Ruyan,et al. An Efficient Timing Synchronization Scheme for Asymmetrically Clipped Optical Orthogonal Frequency Division Multiplexing Systems Using Implicit Training[A].In:Proceeding of the 2010 International Conference on Computer Application and System Modeling (ICCASM 2010)[C].Taiyuan China:2010.v12-338-342.
[36]K. Puntsri, S. Hoffmann, S. Hussin, A. et al. A Low Complexity and High Accuracy Frame Synchronization for Optical OFDM Systems[A].In:Proceeding of the 2011 16th optoelectronics and communications conference (OECC)[C],Kaohsiung:2011.579-580.
[1]Huang Ming-fang, Jianjun Yu, and Dayou Qian, et al. Lightwave centralized WDM-OFDM-PON [A]. In:Proceeding of the ECOC 2008 [C].Brussels Belgium:2008.Th.1.F.5.
[2]Wang Dong, Zou Nianyu, and Zhang Yinghai, et al. Research on next-generation 40Gbit/s OFDM-PON employing OOK modulated upstream signals [A].In:Proceeding of the IET International Conference on Communication Technology and Application (ICCTA) [C]. Beijing China:2011.942-945.
[3]Dayou Qian, Tyrone Tai-on Kwok and Neda Cvijetic, et al.41.25Gb/s real-time OFDM receiver for variable rate WDM-OFDMA-PON transmission [A]. In:Proceeding of the conference on optical fiber communications(OFC)[C].San Diego CA:2010.PDPD9.
[4]Lin Chen, J.G.Yu, and Shuang Chun Wen, et al. A novel scheme for seamless integration of ROF with centralized lightwave OFDM-WDM-PON system [J], Journal of lightwave technology,2009,27(14):2786-2791.
[5]Jianjun Yu, Ming-fang Huang, and Dayou Qian, et al. Centralized lightwave WDM-PON employing 16-QAM intensity modulated OFDM downstream and OOK modulated upstream signals[J], IEEE photonics technology Ietters,2008,20(I8):1545-1547.
[6]Dayou Qian, Junqiang Hu and Pholip Nan Ji, et al.10.8Gb/s OFDMA-PON transmission performance study[A]. In:Proceeding of the Conference on optical fiber communication[C].San Diego CA:2009.NME6.
[7]Yumin Lin, Polung Tien and Maria C.Yuang, et al. A novel passive optical network architecture supporting seamless integration of ROF and OFDMA signals[J]. IEEE phtonics tehnology letter,2010,22(6):419-421.
[8]Neda Cvijetic, Dayou Qian and Junqiang Hu, 100Gb/s optical access based on optical orthogonal frequency division multiplexing[J], IEEE communications magazine,2010:70-77.
[9]Chien-hung Yeh, Chiwai Chow and Chihhung Hsu,40Gb/s time division multiplexed passive optical networks using downstream OOK and upstream OFDM modulations[J].IEEE photonics technology letters,2010,22(2):118-120.
[10]C.H.Yeh and C.W.Chow, 10Gb/s upstream TDM-PON based on four WDM signals with OFDM-QAM remodulation [A]. In:Proceeding of the phtonics and electro-optics conference[C].Hong-kong:2009.ThLP46.
[11]Xi Zheng, Xiao Liu, and Chunning Hou, et al. A novel OFDM-PON architecture using single side band OFDM for dwon stream and subcarrier multiplexed ask for up stream[A]. In:Proceeding of the SPIE-OSA-IEEE asia communications and photonics[C], Shanghai: 2010.76330K-1-5.
[12]Dong WANG, Nianyu ZOU, Yinghai ZHANG, et al. A Novel Design of Passive Optical Network Supporting Triple-format OFDM Signals [J]. ICIC Express Letters,2012,6(9): 2383-2388.
[13]Jia Z. S., Yu J. J., Ellinas G., et.al. Key enabling technologies for optical-wireless networks: Optical millimeter-wave generation, Wavelength reuse, and Architecture[J]. Journal of Lightwave Technology,2007,25(11):3452-3471.
[14]N.Mohamed, S.M.Idrus and A.B.Mohammad, Review on system architectures for the millimeter wave generation techniques for ROF communication link [A]. IEEE international RF and microwave conference[C].Kuala Lumpur Malaysia:2008.326-330.
[15]A.M.Zin, M.S.Bongsu, and S.M.Idrus, et al. An overview of radio-over-fiber network technology[A].In:Proceeding of the international conference on photonics[C]. Langkawi: 2010.1-3.
[16]H.Chettat, L.M.Simohamed, and Y. Bouslimani, ROF networks:a comprehensive study[A].In:Proceeding of the international symposium on wireless pervasive computing[C]. Santorini:2008.495-498.
[17]Kun xu, Xiaoqiang Sun and Jintong Lin, et al. Enabling ROF techonogies and integration architectures for in-building optical wireless access networks[J]. IEEE photonics journal,2010,2(2):102-112.
[18]David Wake, Anthony Nkansah, and Nathan J.Gomes, Radio over fiber link design for next generation wireless systems[J]. Journal of lightwave technology,2010,28(16):2456-2464.
[19]Alwyn Seeds, Chinpang Liu and Tabassam Ismial, Technologies for radio over fiber systems [A]. In:Proceeding of IEEE summer topical meeting[C].Newport beach CA:2009.TuB11.
[20]Wang Jianping, Xianwei Zhou and Yongxia Xu, et al. Performance improvement of OFDM-ROF system with clipping and filtering technique[J]. IEEE transactions on consumer electronics,2008,54(2):296-299.
[21]Wang Jianping, Bosheng Liu and Xianwei Zhou, PCE algorithm for PAPR reduction in OFDM-ROF system [J].IEEE transaction on consumer electronics,2009,55(3):1078-1082.
[22]Z.Cao Z.Dong, and J.Lu, et al. Optical OFDM signal generation by optical phase modulator and its application in ROF system[A]. In:Proceeding of the European conference on optical communications[C]. Vienna Austria:2009.2.4.4.
[23]Ning Kang,Xuekang Sun,and Jin Liang, et al. Performance improvement of OFDM-ROF system with combined adaptive modulation[A].In:Proceeding of the global mobile congress[C].Shanghai China:2009.1-4.
[24]H.Yang,J.Zeng, and H.D.Jung, et al. Evaluation of effects of MZM nonlinearity on QAM and OFDM signals in ROF transmitter[A].In:Proceeding of the international topical meeting on microwave photonics jointly held with 2009 asia pacific microwave photonics conference[C].Gold Coast Q1d:2008.90-93.
[25]Z.Z.Cao,J.J.Yu, and Minmin Xia, et al. Reduction of intersubcarrier interference and frequency selective fading in OFDM-ROF systems[J]. Journal of lightwave technology,2010, 28(16):2423-2429.
[26]A.Ngoma,M.Sauer,and F.Annunziata,et al.14Gbps 60GHz ROF link employing a simple system architecture and OFDM modulation[A].In:Proceeding of the internaltional topical meeting on microwave photonics[C].Valencia:2009,1-4.
[27]P.Assimakopoulos, L.C.Vieira and A.Nkansah, et al. Modelling of a DFB laser at low bias directly modulated with an OFDM signal for ROF applications[A].In:Proceeding of the international topical meeting on microwave photonics[C].Valencia:2009.1-4.
[28]A.S.Chahine, U.A.K.Okonkwo, and R.Ngah, Study the performance of OFDM radio over fiber for wireless communication systems[A]. IEEE international RF and microwave conference[C].Malaysia:2008.335-338.
[29]Diogo Coelho, Henrique M.Salgado. OFDM signals in WDM radio over fiber networks with fiber bragg grating selection [A].In:Proceeding of the 11th international conference on transparent optical networks (ICTON)[C]. Azores:2009.Tu.A5.5.
[30]Yumin Lin and Polung Tien, Next-generation OFDMA-based passive optical network architecture supporting radio-over-fiber [J]. IEEE Journal of selected areas in communications,2010,28(6):791-799.
[31]Khaled M.Maamoun and Hussein T.Mouftah, A survey and a novel scheme for ROF-PON as FTTx wireless services [A].In:Proceeding of the 6th international symposium on high-capacity optical networks and enabling technologies(HONET)[C]. Alexandria:2009,246-253.
[1]Ze Dong, Zizheng Cao and Jia Lu, et al. Transmission performance of optical OFDM signals with low peak-to-average power ratio by phase modulator [J]. Optics Communications,2009, 282:4194-4197.
[2]Dong WANG, Nianyu ZOU, and Yinghai ZHANG,et al. A Companding Scheme for Peak-to-Average Power Ratio Reduction in Optical Orthogonal Frequency Division Multiplexing Systems[J].Optical Review,2012,19(6):371-375.
[3]Hidenori Taga. A theoretical study of OFDM system performance with respect to subcarrier numbers [J]. Optics Express,2009,17(21):18638-18642.
[4]Yuki Yoshida, Akihiro Maruta and Ken-ichi Kitayama. On the peak-to-average power ratio distribution along fiber in the optical OFDM transmissions [A]. In:Proceeding of the European Conference on Optical Communications[C]. Geneva:2011.We.10.P1.69.
[5]Seung Hee Han, Jae Hong Lee. An overview of peak-to-average power ratio reduction techniques for multicarrier transmission [J]. IEEE Wireless Communications,2005,12(2): 56-65.
[6]Zhou He, Wei Li and Zhiyoung Tao.et al. PAPR reduction in all-optical OFDM systems based on phase pre-empasis [J]. Journal of Physics,2010:1-9.
[7]Stefen H. Muller and Johannes B.Huber. A comparison of peak power reduction schemes for OFDM [A]. In:Proceeding of the IEEE Global Telecommunications Conference (Globecom) [C]. Phoenix Arizona USA:1997.1-5.
[8]Michela Svaluto Moreolo, Raul Munoz and Gabriel Junyent. Novel power efficient optical OFDM based on Hartley transform for intensity modulated direct-detection systems [J]. 2010,28(5):798-805.
[9]Athinarayanan Vallavaraj, Brian G.Stewart and David K.Harrison. An evaluation of modified u-law companding to reduce the PAPR of OFDM systems [J].Int.J.Electron.Commun.. 2010,64:844-857.
[10]J.armstrong. Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J]. Electronics Letters,2002,38(5):246-247.
[11]Jianping Wang, Ying Guo and Xianwei Zhou. PTS-Clipping method to reduce the PAPR in ROF-OFDM system [J]. IEEE transactions on consumer electronics,2009,55(2):356-359.
[12]Xiao Huang, Jianhua Lu and Junli Zheng.et al. Companding transform for reduction in peak-to-average power ratio of OFDM signals [J].IEEE transactions on wireless communications,2004,3(6):2030-2039.
[13]B.Ragini, M.Sushanth Babu and K.Kishan Rao. Companding technique for reducing peak-to-average power ratio in OFDM linear coded systems [J]. International journal of power system operation and enegy management,2011,1(2):48-53.
[14]Xianbin Wang, T.T.Tjhung and C.S.Ng. Reduction of peak-to-average power ratio of OFDM system using a companding technique [J]. IEEE transactions on broadcasting,1999, 45(3):303-307.
[15]Xianbin Wang, T.T.Tjhung and C.S.Ng. Reply to the comments on "Reduction of peak-to-average ratio of OFDM system using a companding technique [J]. IEEE transactions on broadcasting,1999,45(4):420-423.
[16]Tao Jiang and Guangxi Zhu. Nonlinear companding transform for reducing peak-to-average power ratio of OFDM signals [J]. IEEE transactions on broadcasting,2004,50(3):342-346.
[17]Tao Jiang, Yang Yang and Yong-Hua Song. Exponential companding technique for PAPR reduction in OFDM systems [J]. IEEE transactions on broadcasting,2005,51(2):244-248.
[18]Omer Bulakci, Matthias Schuster and Christian-A.Bunge. et al. Reduced complexity precoding based peak-to-average power ratio reduction applied to optical direct-detection OFDM [A]. In:Proceeding of the European conference on optical communications (ECOC) [C]. Brussels Belgium:2008.P.4.11.
[19]Wang Zhongpeng, Xiao Jiangnan and Li Fan. et al. Hadamard precoding for PAPR reduction in optical direct detection OFDM systems [J], Optoelectronics Letters,2011,7(5):0363-0366.
[20]Stefan H.Muller and Johannes B.Huber. A novel peak power reduction schemes for OFDM [A].In:Proceedings of the Int. Symposium on personal indoor and mobile radio communications (PIMRC) [C]. Helsinki Finland:1997.1-5.
[21]Siva Ram Krishna Vadali, Saswat Chakrabaiti and Ratnam Varada RajaKumar. A low complexity PAPR reduction scheme without side information for pilot assisted OFDM systems [A]. In:Proceeding of the 2008 IEEE Region 10 Colloquium and the third ICIIS[C]. Kharagpur India:2008.512.
[22]Weilin Li, Song Yu and Wanyi Gu. et al. FWM mitigation based on serial correlation reduction by partial transmit sequence in coherent optical OFDM systems [J]. Optics Communications,2009,282:3676-3679.
[23]Laia Nadal, Michela Svaluto Moreolo and Josep Maria Fabrega. et al. Comparison of peak power reduction techniques in optical OFDM systems based on FFT and FHT [A]. In: Proceeding of the ICTON [C].2011,We.A1.5.
[24]D.Lowe and X.Huang. Optimal adaptive hyperbolic companding for OFDM [A]. In: Proceeding of the 2nd international conference on wireless broadband and ultra wideband communications Auswireless[C].Sydeney NSW:2007.1-6.
[25]Michael D.Godfrey. The TANH transformation [Z]. Information Systems Laboratory,2009:1-4.
[26]S.C.Jeffery Lee, Florian Breyer and Sebastian Randel.et al. High-speed transmission over multimode fiber using discrete multitone modulation [J]. Journal of optical network,2008, 7(2):183-196.
[1]Jan-Jaap van de beek, Ove Edfors, Magnus Sandell, et al. On channel estimation in OFDM systems [A]. In:Proceedings of the IEEE vehicular technology conference (VTC)[C].Chicago USA:1995.815-819.
[2]Shieh, W., Tucher Rodney S., and Chen Wei, et al. Optical Performance Monitoring through Channel Estimation by Receiver Signal Processing [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Cannes France:2006.1-2.
[3]Meng-Han, Hsieh and Wei Che-Ho. Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency selective fading channels [J]. IEEE Transactions on Consumer Electronics,1998.44(1):217-225.
[4]Morelli, M. and U. Mengali. A comparison of pilot-aided channel estimation methods for OFDM systems [J]. IEEE Transactions on Signal Processing,2001,49(12):3065-3073.
[5]Ivan B. Djordjevic and Bane Vasic, Orthogonal frequency division multiplexing for high-speed optical transmission [J].Optics Express,2006.14(9).3767-3775.
[6]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express, 2008.16(2):841-859.
[7]Jie, P. and C. Chi-Hao. Sparse Volterra model based coherent optical-OFDM channel modeling and compensation [A]. In:Proceedings of the 16th OptoElectronics and Communications Conference (OECC) [C]. Kaohsiung:2011.39-40.
[8]Ishihara, K., Kudo R., and Kobayashi T., et al. Frequency-domain equalization for coherent optical transmission systems [A]. In:Proceedings of the 2011 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2011.1-3.
[9]Nair, J.P. and R.V. Raja Kumar. Channel estimation and equalization based on implicit training in OFDM systems [A]. In:Proceedings of the IFIP International Conference on Wireless and Optical Communications Networks[C]. Bangalore:2006.1-5.
[10]Fan Li, Jianjun Yu and Lin Chen, et al. Reduction of frequency fading and imperfect frequency response with pre-emphasis technique in OFDM-ROF systems [J].Optics communications.2011, 284:4699-4705.
[11]Ahmed N. H. Alnuaimy, Mahamod Ismail, Mohd. A. M. Ali, et al. An improved algorithm for channel estimations of OFDM system based pilot signal [J].World academy of science, engineering and technology,2009.38:66-68.
[12]Mingying, L.. Song Yu and Wanyi Gu, et al. A LMMSE channel estimator for coherent optical OFDM system [A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP)[C]. Shanghai, China:2009.1-2.
[13]Yingkan, C., Adhikari S., Hanik N., et al. Pilot-aided sampling frequency offset compensation for coherent optical OFDM[A]. In:Proceedings of the 2012 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2012.1-3.
[14]W.Shieh. Maximum-likelihood phase and channel estimation for coherent optical OFDM[J].IEEE photonics technology letters,2008,20(8):605-607.
[15]Dar-Zu, H., Chiachien Wei, and Hsingyu Chen,et al. A 40-Gbps OFDM LR-PON system over 100-km fiber employing an economical 10-GHz-based transceiver[A]. In:Proceedings of the 2012 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2012.1-3.
[16]Shengjiao, C., K. Pooi-Yuen and Y. Changyuan. Decision-aided carrier phase estimation for coherent optical OFDM[A]. In:Proceedings of the 16th OptoeElectronics and Communications Conference (OECC) [C].Kaohsiung:2011.425-426.
[17]Xingwen, Y., W. Shieh and T. Yan. Phase Estimation for Coherent Optical OFDM [J]. IEEE Photonics Technology Letters,2007,19(12):919-921.
[18]Zhansheng W., Q. Yaojun and J. Yuefeng. A novel joint frequency offset and channel estimation method for CO-OFDM system[A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP) [C]. Shanghai China:2010.607-608.
[19]Pasandi M.E.M. and D.V. Plant. Improvement of phase noise compensation for coherent optical OFDM via data-aided phase equalizer [A]. In:Proceedings of the Optical Fiber Communication (OFC/NFOEC) [C]. San Diego CA:2010.1-3.
[20]Al-Dweik, A. and R. Hamila. Novel frequency offset estimation technique for OFDM systems using band edge filters[A]. In:Proceedings of the Second IFIP International Conference on Wireless and Optical Communications Networks[C].2005.406-409.
[21]Chun, J.Y., Liu Xiang, and Chandrasekhar S., et al. An efficient and frequency-offset-tolerant channel estimation and synchronization method for PDM CO-OFDM transmission[A]. In: Proceedings of the 2010 36th European Conference and Exhibition on Optical Communication (ECOC) [C]. Torino:2010.1-3.
[22]Yu Changyuan, Pooi-Yuen Kam, Shaoliang Zhang, et al. Phase and frequency offset estimation in coherent optical fiber communication systems[A]. In:Proceedings of the 16th OptoeElectronics and Communications Conference (OECC) [C]. Kaohsiung:2011.421-422.
[23]Schmidt B., A.J. Lowery and J. Armstrong, Impact of PMD in Single-Receiver and Polarization-Diverse Direct-Detection Optical OFDM[J]. Journal of Lightwave Technology,2009. 27(14):2792-2799.
[24]Xiang L. and F. Buchali. A novel channel estimation method for PDM-OFDM enabling improved tolerance to WDM nonlinearity. In:Proceedings of the International Conference on Optical Fiber Communication (OFC) [C]. San Diego CA:2009.1-3.
[25]Xiang Liu and Fred Buchali. Intra-symbol frequency-domain averaging based channel estimation for coherent optical OFDM [J].Optics Express.2008,16(26):21944-21957.
[2]顾畹仪,李国瑞.光纤通信系统[M].北京：北京邮电大学出版社,2006.209-210.
[3]陈雪.无源光网络技术[M].北京：北京邮电大学出版社,2006.1-12.
[4]internet world stats-www.internetworldstats.com/stats.htm
[5]http://www.ciscovni.com/vni_forecast/advanced.html
[6]韦乐平.光网络的发展趋势与挑战[J].电信科学,201 1,27(2):10-14.
[7]Sano A, Yamada E, Masuda H, et al.13.4-Tb/s(134×111-Gb/s/ch)no-guard-interval coherent OFDM transmission over 3600km of SMF with 19-ps average PMD[A]. In:Proceeding of the Eur.Conf. of optical communications[C].Brussels Belgium:2008.Th.3.E.1.
[8]R.Berezdivin, R.Breinig, and R.Topp, Next-generation wireless communications concepts and technologies [J]. IEEE communications magazine,2002,40:108-116.
[9]3GPP TS 36.101,3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA);User Equipment (UE) radio transmission and reception[S].Realse 11.
[10]马修.贝科,LTE-UMTS长期演进理论与实践,北京：人民邮电出版社,2009,12。
[11]IEEE 802.11a-1999 (8802-11:1999/Amd 1:2000(E)),Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications-Amendment 1:High-speed PhysicalLayer in the 5GHzband[S].1999.
[12]IEEE 802.11b-1999 Supplement to 802.11-1999, Wireless LAN MAC and PHY specifications: Higher speed Physical Layer (PHY) extension in the 2.4GHzband[S].1999.
[13]IEEE 802.11e-2005, Wireless LAN Medium Access Control (MAC) and Physical Layer (PHY) specifications:Amendment 8:Medium Access Control (MAC) Quality of Service Enhancements[S].2005.
[14]Youngsu Cho, Myungin Ji and Yangkoo Lee, et al WIFI AP position estimation using contribution from heterogeneous mobile devices[A]. In:Proceeding of the IEEE position location and navigation symposium[C].Myrtle Beach SC:2012.562-567.
[15]Pareit Daan, Lannoo Bart and Moerman Ingrid, et al. The History of WiMAX:A Complete Survey of the Evolution in Certification and Standardization for IEEE 802.16 and WiMAX [J]. IEEE communications survey & Tutorials,2011,14(4):1183-1121.
[16]ITU-T G.995.1. Overview for digital subscriber line (DSL) recommendations[S].2001.
[17]YD/T 1063-2000.接入网技术要求-混合光纤同轴电缆网(HFC)[S].2000.
[18JITU-T G.983.1. Broadband optical access systems based on passive optical network (PON) [S].1998
[19]Cedric Lam, Passive Optical Networks [M]. Burlington USA:Academic Press in an imprint of elsevier,2007.19-29.
[20]Kamal A.E., Blietz B.F. A priority mechanism for the IEEE 802.3ah EPON [A]. In: Proceeding of the IEEE international conference on communications[C].2005:1879-1883.
[21]Kramer G., Mukherjee B., and Pessavento G. Ipact:a dynamic protocol for an Ethernet PON [J]. IEEE communication Magazine,2002,40(2):74-80.
[22]Vica Cale. Gigabit passive optical network-GPON [A].In:Proceeding of the ITI 200729th Int. Conf. on information technology interfaces[C]. Cavtat Croatia:2007.679-684.
[23]Shieh W, Athaudage C, Coherent optical orthogonal frequency division multiplexing [J]. Electronics Letters,2006,42(10):1-2.
[24]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express. 2008.16(2):841-859.
[25]Hung-Chang Chien,Ming-Fang Huang,Jie Liu,et al. Novel Architectures for Orthogonal Wavelength Division Multiplexed Passive Optical Networks (OFDM-PONs) in a 25-GHz Grid[A]. In:Proceeding of the 2011 optical fiber communication conference and exposition (OFC) [C].Los Angles:2011.OTuB6.
[26]Jun-ichi Kani, Naoto Yoshimoto, Next generation PONs:an operator's view[A]. In: Proceedings of the European Conference on Optical Communications (ECOC)[C]. Austria:2009.5.7.4.
[27]Sander L. Jansen, Itsuro Morita, Kamyar Forozesh, and et al. Optical OFDM, a hype or is it for real?[A].In:Proceedings of the 2008 European Conference on Optical Communications (ECOC) [C].Burssels:2008.49-52.
[28]C. H. Wang, C. W. Chow, C. H. Yeh, et al. Demonstration of Hybrid 10Gb/s PON and 10Gb/s OFDM-ROF Architecture Towards Next Generation Access Networks[J].SPIE-OSA-IEEE Asia Communications and Photonics,2009,7632(2):1-6.
[29]P. Chanclou, F.Bourgart and B.Landousies, et al. Technical options for NGPON2 beyond 10G PON [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C]. Geneva:2011.We.9.C.3.
[30]Ning C.Passive Optical Networks for Mobile Backhaul [A].In:Proceeding of the workshop on Photonic Technologies for Access and Bio-Photonics [C].Dusseldorf Germanny:2011.
[31]Helmy A., Fathallah H., and Mouftah H.. Interleaved polling versus multi-thread polling for bandwidth allocation in long-reach PONs [J]. IEEE/OS A Journal of Optical Communications and Networking,2012,4(3):210-218.
[32]Dayou Qian, Neda Cvijetic, and Junqiang Hu, et al. A novel OFDMA-PON architecture with source-freee ONUs for next-generation optical access networks[J]. IEEE photonics technology letters,2009,21 (17):1265-1267.
[33]Dayou Qian, Junqiang Hu, and Philip Nan Ji, et al. 10Gb/s OFDMA-PON for delivery of heterogeneous services[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C]. San Diego CA:2008.OWH4.
[34]Lei Xu, Dayou Qian and Junqiang Hu, et al. OFDMA-based passive optical networks[A].In: Proceeding of the IEEE summer topical meeting[C]. Acapulco:2008.TuE3.1.
[35]Maria Morant,Terence Quinlan, Roberto Liorente,et al. Full Standard Triple-Play Bi-Directional and Full-Duplex CWDM Transmission in Passive Optical Network[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angles CA:2011.OWB3.
[36]Maria Morant, Terence Quinlan, Stuart Walker, et al.Complete Mitigation of Brillouin Scattering Effects in Reflective Passive Optical Networks using Triple-Format OFDM Radio Signals[A]. In:Proceeding of the Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angles CA:2011.JWA72.
[37]Filipe Carvalho, Adolfo Cartaxo.Baseband OFDM and ultrawide band OFDM signals coexistence requirements for extended rach PONs[A]. In:Proceeding of the 12th international conference on transparent optical networks ICTON2010[C]. Munich:2010.Th.A2.6.
[38]Filipe Carvalho, Adolfo Cartaxo.Power requirements for coexisting baseband and wireless OFDM-based signals in hybrid metro-access networks[A]. In:Proceeding of the 13th international conference on transparent optical networks (ICTON) 2011[C].Stockholm: 2011.Tu.A5.6.
[39]J.Armstrong, Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J].Electronics letters,2002,38(5):246-247.
[40]Omer Bulakci, Matthias Schuster, Christian-A. Bunge, et al., Reduced Complexity Precoding Based Peak-to-Average Power Ratio Reduction Applied to Optical Direct-Detection OFDM [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Brussels, Belgium:2008.P.4.11.
[41]Shieh, W., Tucher Rodney S., and Chen Wei, et al. Optical Performance Monitoring through Channel Estimation by Receiver Signal Processing[A].In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Cannes France:2006.1-2.
[1]王文博,郑侃,宽带无线通信OFDM技术[M].北京：人民邮电出版社,2003.2-10.
[2]Chang RW. Synthesis of band-limited orthogonal signals for multichannel data transmission [J], Bell System Technology Journal,1966,45:1775-1796.
[3]Jun-ichi Kani, Naoto Yoshimoto, Next generation PONs:an operator's view[A], In:Proceedings of the European Conference on Optical Communications (ECOC) [C], Austria:2009.5.7.4.
[4]Hiroshi Ichibangase and Kuniaki Motoshima, Next generation optical transport technology [J], Mitsubishi electric advance,2008:6-9.
[5]William Shieh, Ivan Djordjevic, Orthogonal frequency division multiplexing for optical communications [M], Burlington USA:Academic press of Elsevier,2010.22-24.
[6]Weinsten SB, Ebert PM. Data transmission by frequency-dvision multiplexing using the discrete Fourier transform[J], IEEE Trans Commun,1997,19:628-634.
[7]Duhamel P, Hollmann H. Split-radix FFT algorithm[J]. IET electronic letter,1984,20:14-16.
[8]Hara S, Prasad R. Multicarrier techniques for 4G mobile communicationsfM], Boston:Arrech House,2003.33-39.
[9]Armstrong J., Tutorial on optical OFDM [A], In:Proceeding of the 2012 14th international conference on transparent optical networks (ICTON) [C], Coventry United Kingdom:2012.1.
[10]Armstrong J., OFDM for optical communications [J] Journal of lightwave technology,2009, 27(3):189-204.
[11]Dayou Qian, Neda Cvijetic and Junqiang Hu, et al. Optical OFDM transmission in metro/access networks [A], In:Proceeding of the OFC 2009[C],San Diego:2009.OMV1.
[12]Zheng Z.H., Qian Zongjue and Shou G.C., Next-generation passive optical network based on OFDM transmission [A], In:Proceeding of the 2009 WASE international conference on information engineering[C],Taiyuan:2009.329-332.
[13]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express. 2008.16(2):841-859.
[14]Yan Tang, Shieh W.. Coherent optical OFDM transmission up to lTb/s per channel[J]Journal of lightwave technology,2009,27(16):3511-3517.
[15]W.Shieh, X.Yi and Y.Tang. Transmission experiment of multi-gigabit coherent optical OFDM systems over 1000km SSMF fiber [J].Electronics letters,2007,43(3):183-184
[16]W. Shieh and C.Athaudage, Coherent optical orthogonal frequency division multiplexing [J]. Electronics letters,2006,42(10):587-589.
[17]Arthur James Lowery, Liang Bangyuan Du, and Jean Armstrong. Performance of optical OFDM in ultralong-haul WDM lightwave systems [J]. Journal of lightwave technology, 2007,25(1):131-138.
[18]Xuejun Liu, Yaojun Qiao and Yuefeng Ji. electronic compensator for 100G-b/s PDM-CO-OFDM long-hual transmission systems[J]. Chinese optics letters, 2011,9(3):030602-1-5.
[19]Sander L.Jansen, Itsuro Morita and Kamyar Forozesh, et al. Optical OFDM, a hype or is it for real?[A]. In:Proceeding of the 34th Eruropean conference on optical communication[C]. Brussels Belgium:2008.Mo.3.E.3.
[20]Ghislain Mouil Sil, Hadrien Louchet and Andre Richter. Efficient BER estimation for radio-over-fiber systems[A].In:Proceeding of the conference on optical fiber communication and the national fiber optic engineers conference[C], Anaheim CA:2007.1-3.
[21]Rishad Ahmed Shafik Md.Shahriar Rahman and AHM Razibul Islam. On the extended relationship among EVM, BER and SNR as performance metrics [A]. In:Proceeding of the 4th international conference on electrical and computer engineering ICECE[C]. Dhaka Bangladesh:2006.408-411.
[22]Rene-jean Essiambre, Gerard J.Foschini and Peter J.Winzer, et al. The capacity of fiber-optic communication systems[A].In:Proceeding of the conference on optical fiber communication/National fiber optic engineers conference[C].San Diego CA:2008.1-3.
[23]Rene-jean Essiambre, Gerard J.Foschini and Peter J.Winzer, et al. Capacity limits of optical fiber networks [J]. Journal of lightwave technology,2010,28(4):662-701.
[24]John G.Proakis, Masoud Salehi, Gerhard Bauch, Contemporary communications systems using matlab [M],2nd edition, Nelson Engineering,2003.
[25]Hussin S., Puntsri K., Noe R.. Performance analysis of optical OFDM systems [A].In:Proceeding of the 2011 3rd international congress on ultra modern telecommunications and control systems and workshops[C].Budapest:2011.1-5.
[26]Djordjevic IB, Vasic B.Orthogonal frequency division multiplexing for high-speed optical transmission[J].Optics express,2007,15(10):6332-6346.
[27]Berrou C, Glavieux A.Thitimajshima P. Near Shannon limit error-correcting coding and decoding:Turbo codes[A]. In:Proceeding of the 1993 Int. Conf. of Communications[C]. Geneva Swetzerland:1993.1064-1070.
[28]Seung H.H., Jae H.L., An overview of peak-to-average power ratio reduction techniques for multicarrier transmission [J]. IEEE Wireless Communications,2005,12(2):56-65.
[29]J.armstrong. Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J]. Electronics Letters,2002,38(5):246-247.
[30]Yuki Yoshida, Akihiro Maruta and Ken-ichi Kitayama. On the peak-to-average power ratio distribution along fiber in the optical OFDM transmissions [A]. In:Proceeding of the European Conference on Optical Communications[C], Gneva:2011.We.10.P1.69.
[31]Morelli, M. and U. Mengali. A comparison of pilot-aided channel estimation methods for OFDM systems [J], IEEE Transactions on Signal Processing.2001.49(12):3065-3073.
[32]W.Shieh, Maximum-likelihood phase and channel estimation for coherent optical OFDM[J].IEEEE photonics technology letters.2008.20(8):605-607.
[33]Mingying, L., Song Yu and Wanyi Gu, et al. A LMMSE channel estimator for coherent optical OFDM system [A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP) [C]. Shanghai, China:2009.1-2.
[34]Xiaoyong Hao, Kun Qiu, Chongfu Zhang,et al.On the Timing Synchronization Methods for Optical Orthogonal Frequency Division Multiplexing (O-OFDM) Systems:Comparisons and Improvement[A].In:Proceeding of the 2009 Asia communications and photonics conference and exhibition (OSA/ACP)[C].Shanghai China:2009.Th04.
[35]Wang Zhuo, Wu Dapeng, Liu Zuqi, Wang Ruyan,et al. An Efficient Timing Synchronization Scheme for Asymmetrically Clipped Optical Orthogonal Frequency Division Multiplexing Systems Using Implicit Training[A].In:Proceeding of the 2010 International Conference on Computer Application and System Modeling (ICCASM 2010)[C].Taiyuan China:2010.v12-338-342.
[36]K. Puntsri, S. Hoffmann, S. Hussin, A. et al. A Low Complexity and High Accuracy Frame Synchronization for Optical OFDM Systems[A].In:Proceeding of the 2011 16th optoelectronics and communications conference (OECC)[C],Kaohsiung:2011.579-580.
[1]Huang Ming-fang, Jianjun Yu, and Dayou Qian, et al. Lightwave centralized WDM-OFDM-PON [A]. In:Proceeding of the ECOC 2008 [C].Brussels Belgium:2008.Th.1.F.5.
[2]Wang Dong, Zou Nianyu, and Zhang Yinghai, et al. Research on next-generation 40Gbit/s OFDM-PON employing OOK modulated upstream signals [A].In:Proceeding of the IET International Conference on Communication Technology and Application (ICCTA) [C]. Beijing China:2011.942-945.
[3]Dayou Qian, Tyrone Tai-on Kwok and Neda Cvijetic, et al.41.25Gb/s real-time OFDM receiver for variable rate WDM-OFDMA-PON transmission [A]. In:Proceeding of the conference on optical fiber communications(OFC)[C].San Diego CA:2010.PDPD9.
[4]Lin Chen, J.G.Yu, and Shuang Chun Wen, et al. A novel scheme for seamless integration of ROF with centralized lightwave OFDM-WDM-PON system [J], Journal of lightwave technology,2009,27(14):2786-2791.
[5]Jianjun Yu, Ming-fang Huang, and Dayou Qian, et al. Centralized lightwave WDM-PON employing 16-QAM intensity modulated OFDM downstream and OOK modulated upstream signals[J], IEEE photonics technology Ietters,2008,20(I8):1545-1547.
[6]Dayou Qian, Junqiang Hu and Pholip Nan Ji, et al.10.8Gb/s OFDMA-PON transmission performance study[A]. In:Proceeding of the Conference on optical fiber communication[C].San Diego CA:2009.NME6.
[7]Yumin Lin, Polung Tien and Maria C.Yuang, et al. A novel passive optical network architecture supporting seamless integration of ROF and OFDMA signals[J]. IEEE phtonics tehnology letter,2010,22(6):419-421.
[8]Neda Cvijetic, Dayou Qian and Junqiang Hu, 100Gb/s optical access based on optical orthogonal frequency division multiplexing[J], IEEE communications magazine,2010:70-77.
[9]Chien-hung Yeh, Chiwai Chow and Chihhung Hsu,40Gb/s time division multiplexed passive optical networks using downstream OOK and upstream OFDM modulations[J].IEEE photonics technology letters,2010,22(2):118-120.
[10]C.H.Yeh and C.W.Chow, 10Gb/s upstream TDM-PON based on four WDM signals with OFDM-QAM remodulation [A]. In:Proceeding of the phtonics and electro-optics conference[C].Hong-kong:2009.ThLP46.
[11]Xi Zheng, Xiao Liu, and Chunning Hou, et al. A novel OFDM-PON architecture using single side band OFDM for dwon stream and subcarrier multiplexed ask for up stream[A]. In:Proceeding of the SPIE-OSA-IEEE asia communications and photonics[C], Shanghai: 2010.76330K-1-5.
[12]Dong WANG, Nianyu ZOU, Yinghai ZHANG, et al. A Novel Design of Passive Optical Network Supporting Triple-format OFDM Signals [J]. ICIC Express Letters,2012,6(9): 2383-2388.
[13]Jia Z. S., Yu J. J., Ellinas G., et.al. Key enabling technologies for optical-wireless networks: Optical millimeter-wave generation, Wavelength reuse, and Architecture[J]. Journal of Lightwave Technology,2007,25(11):3452-3471.
[14]N.Mohamed, S.M.Idrus and A.B.Mohammad, Review on system architectures for the millimeter wave generation techniques for ROF communication link [A]. IEEE international RF and microwave conference[C].Kuala Lumpur Malaysia:2008.326-330.
[15]A.M.Zin, M.S.Bongsu, and S.M.Idrus, et al. An overview of radio-over-fiber network technology[A].In:Proceeding of the international conference on photonics[C]. Langkawi: 2010.1-3.
[16]H.Chettat, L.M.Simohamed, and Y. Bouslimani, ROF networks:a comprehensive study[A].In:Proceeding of the international symposium on wireless pervasive computing[C]. Santorini:2008.495-498.
[17]Kun xu, Xiaoqiang Sun and Jintong Lin, et al. Enabling ROF techonogies and integration architectures for in-building optical wireless access networks[J]. IEEE photonics journal,2010,2(2):102-112.
[18]David Wake, Anthony Nkansah, and Nathan J.Gomes, Radio over fiber link design for next generation wireless systems[J]. Journal of lightwave technology,2010,28(16):2456-2464.
[19]Alwyn Seeds, Chinpang Liu and Tabassam Ismial, Technologies for radio over fiber systems [A]. In:Proceeding of IEEE summer topical meeting[C].Newport beach CA:2009.TuB11.
[20]Wang Jianping, Xianwei Zhou and Yongxia Xu, et al. Performance improvement of OFDM-ROF system with clipping and filtering technique[J]. IEEE transactions on consumer electronics,2008,54(2):296-299.
[21]Wang Jianping, Bosheng Liu and Xianwei Zhou, PCE algorithm for PAPR reduction in OFDM-ROF system [J].IEEE transaction on consumer electronics,2009,55(3):1078-1082.
[22]Z.Cao Z.Dong, and J.Lu, et al. Optical OFDM signal generation by optical phase modulator and its application in ROF system[A]. In:Proceeding of the European conference on optical communications[C]. Vienna Austria:2009.2.4.4.
[23]Ning Kang,Xuekang Sun,and Jin Liang, et al. Performance improvement of OFDM-ROF system with combined adaptive modulation[A].In:Proceeding of the global mobile congress[C].Shanghai China:2009.1-4.
[24]H.Yang,J.Zeng, and H.D.Jung, et al. Evaluation of effects of MZM nonlinearity on QAM and OFDM signals in ROF transmitter[A].In:Proceeding of the international topical meeting on microwave photonics jointly held with 2009 asia pacific microwave photonics conference[C].Gold Coast Q1d:2008.90-93.
[25]Z.Z.Cao,J.J.Yu, and Minmin Xia, et al. Reduction of intersubcarrier interference and frequency selective fading in OFDM-ROF systems[J]. Journal of lightwave technology,2010, 28(16):2423-2429.
[26]A.Ngoma,M.Sauer,and F.Annunziata,et al.14Gbps 60GHz ROF link employing a simple system architecture and OFDM modulation[A].In:Proceeding of the internaltional topical meeting on microwave photonics[C].Valencia:2009,1-4.
[27]P.Assimakopoulos, L.C.Vieira and A.Nkansah, et al. Modelling of a DFB laser at low bias directly modulated with an OFDM signal for ROF applications[A].In:Proceeding of the international topical meeting on microwave photonics[C].Valencia:2009.1-4.
[28]A.S.Chahine, U.A.K.Okonkwo, and R.Ngah, Study the performance of OFDM radio over fiber for wireless communication systems[A]. IEEE international RF and microwave conference[C].Malaysia:2008.335-338.
[29]Diogo Coelho, Henrique M.Salgado. OFDM signals in WDM radio over fiber networks with fiber bragg grating selection [A].In:Proceeding of the 11th international conference on transparent optical networks (ICTON)[C]. Azores:2009.Tu.A5.5.
[30]Yumin Lin and Polung Tien, Next-generation OFDMA-based passive optical network architecture supporting radio-over-fiber [J]. IEEE Journal of selected areas in communications,2010,28(6):791-799.
[31]Khaled M.Maamoun and Hussein T.Mouftah, A survey and a novel scheme for ROF-PON as FTTx wireless services [A].In:Proceeding of the 6th international symposium on high-capacity optical networks and enabling technologies(HONET)[C]. Alexandria:2009,246-253.
[1]Ze Dong, Zizheng Cao and Jia Lu, et al. Transmission performance of optical OFDM signals with low peak-to-average power ratio by phase modulator [J]. Optics Communications,2009, 282:4194-4197.
[2]Dong WANG, Nianyu ZOU, and Yinghai ZHANG,et al. A Companding Scheme for Peak-to-Average Power Ratio Reduction in Optical Orthogonal Frequency Division Multiplexing Systems[J].Optical Review,2012,19(6):371-375.
[3]Hidenori Taga. A theoretical study of OFDM system performance with respect to subcarrier numbers [J]. Optics Express,2009,17(21):18638-18642.
[4]Yuki Yoshida, Akihiro Maruta and Ken-ichi Kitayama. On the peak-to-average power ratio distribution along fiber in the optical OFDM transmissions [A]. In:Proceeding of the European Conference on Optical Communications[C]. Geneva:2011.We.10.P1.69.
[5]Seung Hee Han, Jae Hong Lee. An overview of peak-to-average power ratio reduction techniques for multicarrier transmission [J]. IEEE Wireless Communications,2005,12(2): 56-65.
[6]Zhou He, Wei Li and Zhiyoung Tao.et al. PAPR reduction in all-optical OFDM systems based on phase pre-empasis [J]. Journal of Physics,2010:1-9.
[7]Stefen H. Muller and Johannes B.Huber. A comparison of peak power reduction schemes for OFDM [A]. In:Proceeding of the IEEE Global Telecommunications Conference (Globecom) [C]. Phoenix Arizona USA:1997.1-5.
[8]Michela Svaluto Moreolo, Raul Munoz and Gabriel Junyent. Novel power efficient optical OFDM based on Hartley transform for intensity modulated direct-detection systems [J]. 2010,28(5):798-805.
[9]Athinarayanan Vallavaraj, Brian G.Stewart and David K.Harrison. An evaluation of modified u-law companding to reduce the PAPR of OFDM systems [J].Int.J.Electron.Commun.. 2010,64:844-857.
[10]J.armstrong. Peak-to-average power reduction for OFDM by repeated clipping and frequency domain filtering [J]. Electronics Letters,2002,38(5):246-247.
[11]Jianping Wang, Ying Guo and Xianwei Zhou. PTS-Clipping method to reduce the PAPR in ROF-OFDM system [J]. IEEE transactions on consumer electronics,2009,55(2):356-359.
[12]Xiao Huang, Jianhua Lu and Junli Zheng.et al. Companding transform for reduction in peak-to-average power ratio of OFDM signals [J].IEEE transactions on wireless communications,2004,3(6):2030-2039.
[13]B.Ragini, M.Sushanth Babu and K.Kishan Rao. Companding technique for reducing peak-to-average power ratio in OFDM linear coded systems [J]. International journal of power system operation and enegy management,2011,1(2):48-53.
[14]Xianbin Wang, T.T.Tjhung and C.S.Ng. Reduction of peak-to-average power ratio of OFDM system using a companding technique [J]. IEEE transactions on broadcasting,1999, 45(3):303-307.
[15]Xianbin Wang, T.T.Tjhung and C.S.Ng. Reply to the comments on "Reduction of peak-to-average ratio of OFDM system using a companding technique [J]. IEEE transactions on broadcasting,1999,45(4):420-423.
[16]Tao Jiang and Guangxi Zhu. Nonlinear companding transform for reducing peak-to-average power ratio of OFDM signals [J]. IEEE transactions on broadcasting,2004,50(3):342-346.
[17]Tao Jiang, Yang Yang and Yong-Hua Song. Exponential companding technique for PAPR reduction in OFDM systems [J]. IEEE transactions on broadcasting,2005,51(2):244-248.
[18]Omer Bulakci, Matthias Schuster and Christian-A.Bunge. et al. Reduced complexity precoding based peak-to-average power ratio reduction applied to optical direct-detection OFDM [A]. In:Proceeding of the European conference on optical communications (ECOC) [C]. Brussels Belgium:2008.P.4.11.
[19]Wang Zhongpeng, Xiao Jiangnan and Li Fan. et al. Hadamard precoding for PAPR reduction in optical direct detection OFDM systems [J], Optoelectronics Letters,2011,7(5):0363-0366.
[20]Stefan H.Muller and Johannes B.Huber. A novel peak power reduction schemes for OFDM [A].In:Proceedings of the Int. Symposium on personal indoor and mobile radio communications (PIMRC) [C]. Helsinki Finland:1997.1-5.
[21]Siva Ram Krishna Vadali, Saswat Chakrabaiti and Ratnam Varada RajaKumar. A low complexity PAPR reduction scheme without side information for pilot assisted OFDM systems [A]. In:Proceeding of the 2008 IEEE Region 10 Colloquium and the third ICIIS[C]. Kharagpur India:2008.512.
[22]Weilin Li, Song Yu and Wanyi Gu. et al. FWM mitigation based on serial correlation reduction by partial transmit sequence in coherent optical OFDM systems [J]. Optics Communications,2009,282:3676-3679.
[23]Laia Nadal, Michela Svaluto Moreolo and Josep Maria Fabrega. et al. Comparison of peak power reduction techniques in optical OFDM systems based on FFT and FHT [A]. In: Proceeding of the ICTON [C].2011,We.A1.5.
[24]D.Lowe and X.Huang. Optimal adaptive hyperbolic companding for OFDM [A]. In: Proceeding of the 2nd international conference on wireless broadband and ultra wideband communications Auswireless[C].Sydeney NSW:2007.1-6.
[25]Michael D.Godfrey. The TANH transformation [Z]. Information Systems Laboratory,2009:1-4.
[26]S.C.Jeffery Lee, Florian Breyer and Sebastian Randel.et al. High-speed transmission over multimode fiber using discrete multitone modulation [J]. Journal of optical network,2008, 7(2):183-196.
[1]Jan-Jaap van de beek, Ove Edfors, Magnus Sandell, et al. On channel estimation in OFDM systems [A]. In:Proceedings of the IEEE vehicular technology conference (VTC)[C].Chicago USA:1995.815-819.
[2]Shieh, W., Tucher Rodney S., and Chen Wei, et al. Optical Performance Monitoring through Channel Estimation by Receiver Signal Processing [A]. In:Proceedings of the European Conference on Optical Communications (ECOC) [C].Cannes France:2006.1-2.
[3]Meng-Han, Hsieh and Wei Che-Ho. Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency selective fading channels [J]. IEEE Transactions on Consumer Electronics,1998.44(1):217-225.
[4]Morelli, M. and U. Mengali. A comparison of pilot-aided channel estimation methods for OFDM systems [J]. IEEE Transactions on Signal Processing,2001,49(12):3065-3073.
[5]Ivan B. Djordjevic and Bane Vasic, Orthogonal frequency division multiplexing for high-speed optical transmission [J].Optics Express,2006.14(9).3767-3775.
[6]W. Shieh, H. Bao and Y.Tang, Coherent optical OFDM:theory and design [J]. Optics Express, 2008.16(2):841-859.
[7]Jie, P. and C. Chi-Hao. Sparse Volterra model based coherent optical-OFDM channel modeling and compensation [A]. In:Proceedings of the 16th OptoElectronics and Communications Conference (OECC) [C]. Kaohsiung:2011.39-40.
[8]Ishihara, K., Kudo R., and Kobayashi T., et al. Frequency-domain equalization for coherent optical transmission systems [A]. In:Proceedings of the 2011 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2011.1-3.
[9]Nair, J.P. and R.V. Raja Kumar. Channel estimation and equalization based on implicit training in OFDM systems [A]. In:Proceedings of the IFIP International Conference on Wireless and Optical Communications Networks[C]. Bangalore:2006.1-5.
[10]Fan Li, Jianjun Yu and Lin Chen, et al. Reduction of frequency fading and imperfect frequency response with pre-emphasis technique in OFDM-ROF systems [J].Optics communications.2011, 284:4699-4705.
[11]Ahmed N. H. Alnuaimy, Mahamod Ismail, Mohd. A. M. Ali, et al. An improved algorithm for channel estimations of OFDM system based pilot signal [J].World academy of science, engineering and technology,2009.38:66-68.
[12]Mingying, L.. Song Yu and Wanyi Gu, et al. A LMMSE channel estimator for coherent optical OFDM system [A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP)[C]. Shanghai, China:2009.1-2.
[13]Yingkan, C., Adhikari S., Hanik N., et al. Pilot-aided sampling frequency offset compensation for coherent optical OFDM[A]. In:Proceedings of the 2012 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2012.1-3.
[14]W.Shieh. Maximum-likelihood phase and channel estimation for coherent optical OFDM[J].IEEE photonics technology letters,2008,20(8):605-607.
[15]Dar-Zu, H., Chiachien Wei, and Hsingyu Chen,et al. A 40-Gbps OFDM LR-PON system over 100-km fiber employing an economical 10-GHz-based transceiver[A]. In:Proceedings of the 2012 Optical Fiber Communication Conference and Exposition (OFC/NFOEC) [C].Los Angeles CA:2012.1-3.
[16]Shengjiao, C., K. Pooi-Yuen and Y. Changyuan. Decision-aided carrier phase estimation for coherent optical OFDM[A]. In:Proceedings of the 16th OptoeElectronics and Communications Conference (OECC) [C].Kaohsiung:2011.425-426.
[17]Xingwen, Y., W. Shieh and T. Yan. Phase Estimation for Coherent Optical OFDM [J]. IEEE Photonics Technology Letters,2007,19(12):919-921.
[18]Zhansheng W., Q. Yaojun and J. Yuefeng. A novel joint frequency offset and channel estimation method for CO-OFDM system[A]. In:Proceedings of the Communications and Photonics Conference and Exhibition (ACP) [C]. Shanghai China:2010.607-608.
[19]Pasandi M.E.M. and D.V. Plant. Improvement of phase noise compensation for coherent optical OFDM via data-aided phase equalizer [A]. In:Proceedings of the Optical Fiber Communication (OFC/NFOEC) [C]. San Diego CA:2010.1-3.
[20]Al-Dweik, A. and R. Hamila. Novel frequency offset estimation technique for OFDM systems using band edge filters[A]. In:Proceedings of the Second IFIP International Conference on Wireless and Optical Communications Networks[C].2005.406-409.
[21]Chun, J.Y., Liu Xiang, and Chandrasekhar S., et al. An efficient and frequency-offset-tolerant channel estimation and synchronization method for PDM CO-OFDM transmission[A]. In: Proceedings of the 2010 36th European Conference and Exhibition on Optical Communication (ECOC) [C]. Torino:2010.1-3.
[22]Yu Changyuan, Pooi-Yuen Kam, Shaoliang Zhang, et al. Phase and frequency offset estimation in coherent optical fiber communication systems[A]. In:Proceedings of the 16th OptoeElectronics and Communications Conference (OECC) [C]. Kaohsiung:2011.421-422.
[23]Schmidt B., A.J. Lowery and J. Armstrong, Impact of PMD in Single-Receiver and Polarization-Diverse Direct-Detection Optical OFDM[J]. Journal of Lightwave Technology,2009. 27(14):2792-2799.
[24]Xiang L. and F. Buchali. A novel channel estimation method for PDM-OFDM enabling improved tolerance to WDM nonlinearity. In:Proceedings of the International Conference on Optical Fiber Communication (OFC) [C]. San Diego CA:2009.1-3.
[25]Xiang Liu and Fred Buchali. Intra-symbol frequency-domain averaging based channel estimation for coherent optical OFDM [J].Optics Express.2008,16(26):21944-21957.