共查询到20条相似文献,搜索用时 31 毫秒
1.
Kwanil Lee Sil-Gu Mun Chang-Hee Lee Sang Bae Lee 《Photonics Technology Letters, IEEE》2008,20(9):679-681
A novel, reliable wavelength-division-multiplexed passive optical network (WDM-PON) with self-protection capability is proposed. By utilizing the routing characteristics of N x N arrayed waveguide grating, the proposed architecture can provide automatic protection against any fiber cut between central office and optical network unit (ONU). Compared with the conventional schemes, this scheme adopts colorless ONUs, thus leading to a decrease in the costs of operation, administration, and maintenance, as well as the production cost. Without the performance degradation, the proposed WDM-PON scheme can offer a reliable network service. In the experiment, the protection performance was demonstrated in the carrier-distributed 1.25-Gb/s WDM transmission over 20-km single-mode fiber. 相似文献
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The higher bandwidth utilization of wavelength-division-multiplexing passive optical networks (WDM-PONs) can be problematic if the link failure is not repaired in a timely manner since major data losses may occur in the event of link failure. Therefore, developing robust WDM-PON architectures with an effective protection capability is an essential task when designing optical access networks. Although the literature contains many proposals for WDM-PON protection schemes, the majority of these schemes protect either the feeder fibers or the distribution fibers, but not both. By exploiting the cyclic properties of the AWG and establishing appropriate interconnections between matched pairs of ONUs such that one ONU in the pair can use the distribution fiber assigned to its partner for backup purposes, the proposed scheme can protect both the feeder fibers and the distribution fibers through the designated protection streams in feeder fiber 3. Additionally, five operational modes of the proposed scheme are detailed with the proposed wavelength assignment scheme, the operational sequence, and the operation flow chart of decision circuit in the ONU/OLT. The analytical results have shown that the proposed scheme not only provides a full protection capability for WDM-PON networks, but also has a lower unavailability, a lower construction cost, and a reduced wavelength requirement than existing representative protection schemes. Finally, an analysis of the power budget and the recovery time has confirmed the practical feasibility of the proposed scheme. 相似文献
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Fady I. El-Nahal 《光电子快报》2017,13(1):67-69
We investigate a wavelength-division-multiplexing passive optical network (WDM-PON) with centralized lightwave and direct detection. The system is demonstrated for symmetric 10 Gbit/s differential phase-shift keying (DPSK) downstream signals and on-off keying (OOK) upstream signals, respectively. A wavelength reused scheme is employed to carry the upstream data by using a reflective semiconductor optical amplifier (RSOA) as an intensity modulator at the optical network unit (ONU). The constant-intensity property of the DPSK modulation format can keep high extinction ratio (ER) of downstream signal and reduce the crosstalk to the upstream signal. The bit error rate (BER) performance of our scheme shows that the proposed 10 Gbit/s symmetric WDM-PON can achieve error free transmission over 25-km-long fiber transmission with low power penalty. 相似文献
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A time interleaved differential phase shift keying (DPSK) remodulation technique is proposed to mitigate the effect of Rayleigh backscattering (RBS)-induced noise in a single fiber colorless wavelength-division-multiplexing passive optical network (WDM-PON). In order to achieve a cost effective optical network unit (ONU) solution without dedicated laser sources for upstream signals to provide optimum symmetric capacity in a colorless WDM-PON, remodulation becomes the core attraction. Also as the performance of colorless WDM-PON systems suffers from the transmission impairments due to RBS, it is mitigated by using this remodulation scheme. Simulation results show that downstream and upstream signals achieve the error-free performance at 10 Gbit/s with negligible penalty, and enhance the tolerance to RBS-induced noise over a 25 km single-mode fiber. 相似文献
5.
《Photonics Technology Letters, IEEE》2009,21(14):990-992
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We propose and experimentally demonstrate a novel flexible optical network unit (ONU) internetworking architecture over a wavelength-division multiplexed passive optical network (WDM-PON). By employing our designated wavelength assignment and remodulating the downstream differential phase-shift keying signal as the ONU internetworking carrier, one ONU can broadcast its own message to all other ONUs, with negligible signal interference. Moreover, the inter-ONU communication can further be partitioned into arbitrary virtual private groups of ONUs by employing designated RF tones for identification and control. It was experimentally demonstrated that the performance degradation due to the introduction of RF tones is negligible compared with the full broadcast case. Our proposed scheme can provide high flexibility and practical implementation for WDM-PONs. 相似文献
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波分复用无源光网络技术(WDM-PON)是被FASN认为可以作为下一代光纤接入网技术来研究[1]587-588。反射式半导体光放大器(RSOA)可以解决WDM-PON中光网络单元(ONU)无色化问题[2]。文章先简单介绍WDM-PON技术,在重点研究基于RSOA对WDM-PON系统中上行光源的再调制技术基础上,用OptiSystem软件对基于RSOA的WDM-PON系统仿真,验证基于RSOA的WDM-PON系统的可靠性。最后,总结WDM技术应用前景。 相似文献
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介绍了下一代多波长光接入网的主要技术及其体系架构,主要包括WDM—PON技术、WDM/TDM—PON技术、WDM/OCDMA—PON技术。重点介绍了WDM—PON无色ONU的实现方式,其中采用RSOA实现ONU无色化的体系架构有很大的应用前景。分析了下一代基于广播电视的WDM-PON体系架构的研究现状和发展方向。 相似文献
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EPON关键技术及其展望 总被引:2,自引:0,他引:2
无源光网络接入技术由于其支持高带宽和长距离等特性,将成为解决最后一公里问题的最佳方案.文章对以太无源光网络(EPON)的ONU自动发现、ONU测距、动态带宽分配等关键技术进行了分析和研究,最后对其技术发展方向10G EPON以及WDM-PON进行了展望. 相似文献
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Chien-Hung Yeh Chi-Wai Chow Yu-Fu Wu Fu-Yuan Shih Sien Chi 《Optical Fiber Technology》2010,16(3):178-181
High capacity time-division-multiplexed passive optical network (TDM-PON) is an emerging fiber access network that deploys optical access lines between a carrier’s central office (CO) and a customer sites. In this investigation, we demonstrate and analyze the continuous wave (CW) upstream effect in TDM-PONs. Besides, we also propose and design a protection apparatus in each optical network unit (ONU) to avoid a CW upstream traffic in TDM-PONs due to sudden external environment change or ONU failure. When an upstream CW injection occurs in TDM access network, the protection scheme can stop the CW effect within a few ms to maintain the entire data traffic. 相似文献
14.
ZHANG Wei-feng XIN Xiang-jun ZHANG Qi ZHANG Zi-xing NAI Wei SHI Yan 《中国邮电高校学报(英文版)》2010,17(4):125-128
A novel architecture for wavelength-division-multiplexing passive optical network (WDM-PON) with centralized light-wave is proposed and demonstrated. At the optical line terminal (OLT) session of this architecture, optical differential quadrature phase shift keying (DQPSK) modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission. At the optical network unit (ONU), part of the downstream optical power is remodulated with on-off keying (OOK) intensity modulation at 10 Gbit/s for upstream without additional laser. Simulation results show that the power penalties of the downstream for 20 km single-mode fiber (SMF) transmission and multi-channels are negligible. While for the upstream, the power penalties are obvious. The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters, power penalties can be reduced, although the transmission distance is limited. 相似文献
15.
Tae-Young Kim Sang-Kook Han 《Photonics Technology Letters, IEEE》2006,18(22):2350-2352
We proposed and experimentally demonstrated the reflective semiconductor optical amplifier (RSOA)-based wavelength-division-multiplexed passive optical network (WDM-PON) scheme where not only up/downlink data services but also broadcasting service could be provided using a single optical source. In the proposed scheme, the digital signal and subcarrier multiplexing (SCM) signal for downstream were simultaneously modulated by a single distributed feedback laser diode and RSOA in optical network unit remodulated downstream source as an upstream. Without performance deterioration of digital signals both in up- and downstream, the proposed WDM-PON scheme can stably offer the SCM signal for broadcasting service. In the experiment, 1-Gb/s digital signals both for up- and downstream and 20-Mb/s SCM signal at 2.2 GHz for broadcasting were demonstrated in 10-km bidirectional link 相似文献
16.
A novel architecture for wavelength-division-multiplexing passive optical network(WDM-PON)with centralized light-wave is proposed and demonstrated.At the optical line terminal(OLT)session of this architecture,optical differential quadrature phase shift keying(DQPSK)modulated signal with constant-intensity at 10 Gbit/s is utilized for downstream transmission.At the optical network unit(ONU),part of the downstream optical power is remodulated with on-off keying(OOK)intensity modulation at 10 Gbit/s for upstream without additional laser.Simulation results show that the power penalties of the downstream for 20 km single-mode fiber(SMF)transmission and multi-channels are negligible.While for the upstream,the power penalties are obvious.The simulation results and analysis also reflect that by reducing the launch power of DQPSK transmitters,power penalties can be reduced,although the transmission distance is limited. 相似文献
17.
HanWu Hu Hanan Anis 《Lightwave Technology, Journal of》2008,26(8):870-881
This paper presents a general formulation for the impact of back-reflection in wavelength division multiplexing-passive optical networks (WDM-PON) access networks. The analysis is applied to various wavelength-independent optical network unit (ONU) configurations such as amplified spontaneous emission (ASE)-locked Fabry-Perot (FP) lasers, reflective semiconductor optical amplifiers or injection locked FP using the downstream signal. The power penalty due to beat noise and its dependence on relative intensity noise, transmitter linewidth, and receiver bandwidth is investigated. The optimal gain at the ONU that minimizes the effect of beat noise is also found. The results show that the power penalty decreases as the linewidth of the the optical line terminal (OLT) and ONU light source increase. 相似文献
18.
《Photonics Technology Letters, IEEE》2008,20(17):1479-1481
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Chao-Chin Yang 《Photonics Technology Letters, IEEE》2007,19(7):516-518
One novel decoding scheme of prime codes for interference elimination is proposed for optical code-division multiple-access network. This scheme uses the correlation property of prime codes for interference elimination without additional processing, and thus simplifies the coder implementation. By taking advantage of the cyclic property of the prime codes in the same code groups, the proposed compact encoder is low cost and suitable for the application of passive optical network (PON). In addition, the information encoding of each optical network unit (ONU) can adopt two-code keying using a simplified ONU decoder for performance enhancement. Thus, this is an economical solution for end users in the PON 相似文献
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Kwanil Lee Sun Do Lim Young Min Jhon Chul Han Kim Paolo Ghelfi An Truong Nguyen Luca Poti Sang Bae Lee 《Optical Fiber Technology》2012,18(2):112-116
We propose and experimentally demonstrate a novel wavelength-division-multiplexed passive optical network (WDM-PON) scheme for providing broadcasting service by using an inverted amplified spontaneous emission (ASE) from a semiconductor optical amplifier (SOA). In this scheme, single pump signal is converted into multiple wavelengths signal by spectrum sliced wavelength conversion. We expect it could be very practical and cost-effective solution for broadcasting in WDM-PON due to its simplicity. 相似文献