共查询到20条相似文献,搜索用时 31 毫秒
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报告了一个用于低频射频天线网络LOFAR的160 Gbit/s 演示平台.文章介绍了LOFAR网络结构以及用于LOFAR长臂的OTDM/WDM系统结构,回顾并探讨了用于实现160 Gbit/s系统的关键技术,并介绍了实验室中实现该160 Gbit/s OTDM/WDM演示平台所采用的技术方案。出于经济性考虑,所有的关键系统功能都采用自己搭建方案. 相似文献
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C. C. Hiew H. T. Chuah H. A. Abdul-Rashid F. M. Abbou S. P. Majumder 《Fiber and Integrated Optics》2005,24(5):457-470
The impact of a post-OTDM-demultiplexing optical filter on the performance of dense on-off keying (OOK) optical time division multiplexing (OTDM)—wavelength division multiplexing (WDM) systems was studied. For return-to-zero (RZ) modulation, it was found that the additional filter working in a double-tier filter configuration did not offer any significant improvements to performance when the signal pulse width is optimized. Improvements generally increase only when the signal pulse width deviates from its optimal value and only for low spectral densities. For ideal non-return-to-zero (NRZ) modulation, however, significant improvements of around 1 dB are obtained using the double-tier configuration over a large range of spectral densities. 相似文献
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CrostalkinWDMSCMSystemsduetoSRSZHAOLiangXUDayongWUDemingYUANHongXUAnshi(DepartmentofElectronics,BeijingUniversityNationalKeyL... 相似文献
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Effects of pulse chirp on supercontinuum produced in dispersion decreasing fibre 总被引:1,自引:0,他引:1
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The supercontinuum (SC) source plays a key role in wavelength division multiplexing over the optical time division multiplexing (WDM/OTDM) transmission system. The SC produced in dispersion decreasing fibre (DDF) is wider and flatter than that produced in dispersion shifted fibre (DSF). In this paper, a SC producing process in DDF is numerically simulated, the effects of pump pulse chirp on the SC width and flatness are initially studied and the corresponding theoretical explanations are given. Particularly, we have analysed and compared the evolutions of the SC along DDF pumped by different chirp pulses. Several valuable conclusions are obtained. 相似文献
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提出了一种利用Fabry-Perot(FP)半导体激光器同步提取波长转换的分路光时钟的新方法,并对该方法进行了数值模拟和实验验证.光注入半导体激光器会产生非线性单周期振荡特性,利用交叉增益调制效应及对单周期振荡的微波锁频效应,可从光时分复用信号中提取出波长转换的分路光时钟.采用一个FP半导体激光器作为全光分路时钟提取及波长转换器,数值模拟实现了从波长为1555 nm、速率为2×20 Gb/s的光时分复用信号中提取出波长转换为1550 nm、重复频率为20 GHz的分路光时钟,实验完成了从波长为155024 nm、重复频率为1236 GHz光脉冲信号中提取出相位噪声为-105 dBc/Hz的波长为154591 nm、重复频率618 GHz的分频光时钟.此外还详细研究了注入光功率、波长失谐、FP激光器偏置电流及纵模选择对光时钟提取的影响,实验结果和数值模拟结果符合.该方法在光时分复用混合波分复用通信系统中实现全光解复用及波长路由有着重要的应用价值.
关键词:
波长转换
时钟提取
光注入
非线性动力学 相似文献
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A radio-over-fiber (RoF) distribution system incorporating both sub-carrier multiplexing and wavelength division multiplexing (WDM) technologies is presented. This signal is directly modulated onto three high-speed lasers. Bragg filters are employed at the receiver base station in order to both demultiplex the required optical channel, and ensure that the detected signal is single side band (in order to overcome dispersion limitations of the link). System spectral efficiency is optimised by wavelength interleaving. The channel spacing between the WDM channels is varied and the system performance for different values of channel spacing and spectral efficiencies is investigated. The results show that wavelength interleaving is a reliable technique that could be used to increase the spectral efficiency of RoF systems. 相似文献
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A New 1×K Tunable Multi-wavelength Router and its Features 总被引:2,自引:0,他引:2
GAN Chaoqin SUN Xiaohan ZHANG Mingde 《Chinese Journal of Lasers》2002,11(1):61-65
1 Introduction Wavelengthrouters (WRs)arekeydevicesinwavelength routingall opticalnetworks.Recently ,researchfortheWRshasbeenoneofhotspotsinwavelengthdivisionmultiplexing (WDM )networktechnologies[1,2 ] .Bydifferentroutingpatterns,theWRscanbedividedintotwokind… 相似文献
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Tunable wavelength routers (TWRs) for multiple wavelength selection are key devices in dynamic wavelength-routing wavelength division multiplexing (WDM) networks. In this paper, by cascading conventional 2×2 TWRs, a new 1×K TWR is proposed for large-scale dynamic wavelength-routing WDM networks. When the cascading numbers are smaller, the 1×K TWR can be directly applied to networking WDM networks. When the cascading numbers are larger, the 1×K TWR can be carried out by the integrating method and be extensively used to networking various multi-wavelength optical networks by the way of “EDFA+TWR”. Though the cascading method proposed is based on the acousto-optic TWRs, it can be also applied to cascading other kinds of TWRs. 相似文献
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Reference-frame-independent quantum key distribution of wavelength division multiplexing with multiple quantum channels
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Zhongqi Sun 《中国物理 B》2021,30(11):110303-110303
Reference-frame-independent quantum key distribution (RFI-QKD) can allow a quantum key distribution system to obtain the ideal key rate and transmission distance without reference system calibration, which has attracted much attention. Here, we propose an RFI-QKD protocol based on wavelength division multiplexing (WDM) considering finite-key analysis and crosstalk. The finite-key bound for RFI-QKD with decoy states is derived under the crosstalk of WDM. The resulting secret key rate of RFI-QKD, which is more rigorous, is obtained. Simulation results reveal that the secret key rate of RFI-QKD based on WDM is affected by the multiplexing channel number, as well as crosstalk between adjacent channels. 相似文献
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In this paper a hybrid multiplexing technique has been presented that merges WDM and OTDM multiplexing technologies. The WDM-OTDM hybrid realizes wavelength parallel bus architecture and is inherent with features of high spectral efficiency, high scalability and bandwidth elasticity. Simulations and experiments were carried out to investigate the selection of most suitable modulation format, dispersion compensation technique and erbium doped fiber amplifier (EDFA) noise figure for WDM-OTDM hybrid, where link lengths exceeding 500 km at high Q-values was achieved. 相似文献
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提出一种利用双向使用高非线性光纤(HNLF)实现同时解复用出两路信号的全光解复用方案.将复用信号和控制光的混合信号从HNLF的两端同时注入,复用信号中的某一路信号通过交叉相位调制使控制光产生蓝移或红移,在HNLF的输出端用窄带滤波器将控制光的蓝移或红移部分滤出从而同时实现两路信号解复用.理论分析了信号光和控制光在HNLF中的相互作用和解复用原理.搭建80 Gbit/s光时分复用系统,对双向使用HNLF的解复用结构进行了实验研究.在HNLF的两个输出端同时实现不同信道的无误码解复用,其中信道解复用的最大功率代价为2.6 dB. 相似文献
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Transmission capacity for optical undersea cable systems is growing remarkably and a more than 500-fold increase has been achieved for commercial systems over the past 10 years. The first optical fiber cable in the Pacific Ocean went into service in 1989 and has a capacity of 280 Mbit/s per fiber pair. The emergence of an Erbium-doped fiber amplifier paved the way for a drastic capacity increase for these cables, and large capacity optical amplifier undersea cable systems with 5 Gbit/s per fiber pair were constructed worldwide in 1995-1996. Recent 10 Gbit/s-based wavelength division multiplexing (WDM) technologies together with new fibers and new amplifiers have allowed a further increase in capacity up to 160 Gbit/s, and these WDM systems will begin commercial service in both the Pacific Ocean and the Atlantic Ocean in 2000. Research interest is now being directed towards the development of undersea cable systems with a transmission capacity of 1 Tera-bit/s or more. This paper reviews the key technologies for next generation 160 Gbit/s optical undersea cable systems and recent progress towards Tera-bit/s systems. Dispersion managed soliton transmission for future higher bit rate WDM is also discussed. 相似文献
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采用波分复用方法实现飞秒级超快动态过程的脉冲数字显微全息记录和再现。在全息记录过程中,利用BBO倍频晶体对入射激光进行倍频,将基波和谐波分光,并经时间延迟后进入迈克耳孙干涉仪,从而可应用波分复用技术,先后在CCD的一帧图像上记录两张具有不同空间频率的子全息图。采用这种方法,实现了对单脉冲飞秒激光激发空气电离的超快动态过程的全息记录,并通过数字傅里叶变换和数字滤波的方法,分别再现出每张子全息图记录的波前,从而获得了具有飞秒时间分辨的空气等离子体形成和传播过程的动态振幅和相位图像,其单次曝光时间为50 fs,曝光时间间隔为400 fs,相应的曝光频率约为2.5×1012f/s。 相似文献
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Amin Malekmohammadi Ahmad Fauzi Abas Ghafour Amouzad Mahdiraji Mohd Fadlee A. Rasid 《Optics Communications》2009,282(21):4233-4241
The performance of absolute polar duty cycle division multiplexing (AP-DCDM) over wavelength division multiplexing (WDM) system is presented based on the simulation results. The AP-DCDM signal has narrower bandwidth than conventional time division multiplexing (TDM) signal, which makes its implementation in WDM system advantageous. In this paper, characteristics of AP-DCDM and TDM signals in WDM system are compared at the speed of 40 Gbit/s per channel, for the minimum allowed channel spacing and the chromatic dispersion tolerance. The results clearly show that AP-DCDM performs significantly better than TDM. By using AP-DCDM, 1.28 Tbit/s (32 × 40 Gbit/s) was successfully transmitted over 320 km standard single mode fiber. Spectral efficiency of 0.64 b/s/Hz was achieved by using 10 Gbit/s transmitters and receivers without polarization multiplexing. 相似文献
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In this paper, a new algorithm for wavelength assignment has been proposed and its performance is evaluated in terms of blocking probability and fairness. It has been shown that the proposed algorithm offers the least blocking probability. The blocking performance of wavelength division multiplexing (WDM) network has been analyzed for the network having 10 nodes and for varying loads. As the load per link (in Erlangs) increases, the blocking probability increases. The result shows that the performance of first-fit algorithm is better than random algorithm whereas the proposed algorithm offers the least blocking. 相似文献