EPON技术在长庆油田住宅接入网的应用

EPON集成了无源光网络的各种技术优势,而且与以太网技术可以进行无缝融合等。结合长庆油田住宅小区的实际情况,介绍了利用EPON技术构建综合接入网的设计方案,并详细地从业务解决、FTTB用户接入、网管以及ODN布放等方面详细地阐述了其关键技术。

Review on Dynamic Bandwidth Allocation of GPON and EPON

The passive optical network(PON)technology has been drastically improved in recent years.In spite of using the optical technology,the utilization of the entire bandwidth is a very challenging task.The main categories of PON are the Ethernet passive optical network(EPON)and gigabit passive optical network(GPON).These two networks use the dynamic bandwidth allocation(DBA)algorithm to attain the maximum usage of bandwidth,which is provided in the network dynamically according to the need of the customers with the support of the service level agreement(SLA).This paper will provide a clear review about the DBA algorithm of both technologies as well as the comparison。

AN IMPROVED EPON UPSTREAM TRANSMISSION SCHEME WITH ZERO INTER-PERIOD IDLE LOSS

Existing Ethernet Passive Optical Network(EPON) Dynamic Bandwidth Allocation(DBA) algorithms suffer from the disadvantage of idle time loss,which lower the upstream bandwidth utili-zation.This letter proposes an improved upstream transmission scheme with idle-time eliminating mechanism.Theoretical analysis and numerical calculation prove that the improved scheme can ef-fectively eliminate the idle time and enhance the efficiency of upstream link utilization.Simulation results have shown that the bandwidth utilization can be raised up to 15% in heavy-load scenarios while the time delay performance of Assured Forwarding(AF) and Best Effort(BE) services are improved simultaneously.

Modeling for Ethernet passive optical network receiver

A behavior model for the receiver of the Ethernet passive optical network（EPON） is presented. The model consists of a fiber, a photodetector, a transimpedance amplifier （TIA） followed by a limiting amplifier and a clock and data recovery＇ circuit （CDR）. Each sub-model is constructed based on the architecture of a circuit. The noise and jitter in each block such as shot noise, thermal noise, deterministic and random jitter are also considered. The performance of the whole receiver can be evaluated by the simulation of the behavior model, which is faster than the ordinary circuit model and more accurate than the analytical model. The whole model is implemented with C ＋＋ and simulated in Microsoft Visual C ＋＋ 6. 0. Using the Monte Carlo method, the EPON receiver is simulated. The simulation results show a good agreement with experimental ones.

基于光通信芯片的配电光通信解决方案

目前国网实施配电自动化的城市中,其通信系统绝大部分采用基于以太网无源光网络(ethernet passive optical network,EPON)光通信技术。提出一种配电光通信解决方案,其特点是基于配用电专用ONU芯片设计光网络单元(optical network unit,ONU),将ONU内嵌到配电终端中;同时将加密安全模块集成到ONU模块中。与传统配电通信EPON解决方案相比,该方案综合考虑了配电终端通信系统的功能、性能,其将ONU模块与配电终端进行一体化设计,降低了模块功耗。通过配网现场试点表明,该方案不但能实现传统EPON方案的环网保护、大数据量高速、实时接入等功能,而且在系统功耗、安全、可维护性、经济性等方面具有较大优势。

Design and implementation of ethernet passive electronic network over coax

To increase the limit of ethernet over coax （EoC） technology in the bidirectional reform of the hybrid fiber coaxial （HFC） network, an ethernet passive electronic network （EPEN） system based on Coax is proposed and experimentally demonstrated in this paper. The proposed EPEN exploits the existing capabilities of the MAC layer in the ethernet passive optical network （EPON） for reduction of cost of the HFC network. As the MPCP （multi-point control protocol） is introduced in the EPEN, bandwidth control and higher efficiency can be achieved. The experimental results exhibit the throughput of system up to 100Mbps, which meet the requirements of HFC network. To improve the performance of EPEN, frequency division multiplexing （FDM） can be used for further increase of the throughput and more hardware processing modules in the future. can be implemented to enhance the capacity

A novel algorithm for Ethernet-passive-optical-network dynamic bandwidth allocation based on threshold

The Ethemet passive optical network （EPON） is the next generation of broad-band network technique. A crucial issue in EPONs is the sharing of uplink bandwidth among optical network units （ONUs）. This article provides a novel dynamic bandwidth allocation algorithm, i.e. threshold dynamic bandwidth allocation （TDBA）, which is based on adaptive threshold, to increase resource utilization. The algorithm uses ONU data-transmitting rate to adjust optical line terminal （OLT） receiving data threshold from an ONU. Simulation results show that this algorithm can decrease average packet delay and increase network throughput in a l 0G EPON system.

Heuristic polling sequence to enhance sleep count of EPON

Next-generation passive optical networks(PONs)demand power conservation to create a green environment.A reduction in power consumption of the traditional Ethernet passive optical network(EPON)can be achieved by increasing the sleep count in optical network units(ONUs).In this paper,this is accomplished by introducing a first-in-last-out(FILO)polling sequence in the place of a fixed polling sequence to increase the number of ONUs entering sleep mode(sleep count).In a fixed polling sequence,the optical line terminal(OLT)allocates idle time to the ONUs based on the overall load of the ONUs.This leads to a situation that whenever the idle time does not meet the wakeup time threshold of sleep mode,the ONUs are put into doze/active mode,which consumes more power.In the FILO polling sequence,the first polled ONU in the current cycle is made to be polled last in the following cycle.Polling continues in this way,and by this rearrangement,the idle time of delayed poll ONUs increases;hence,it helps to reduce the power consumption.Additionally,a modified load adaptive sequence arrangement(MLASA)method is suggested,where the ONUs are categorized into doze ONUs and sleep ONUs.A numerical simulation of the FILO polling sequence with a vertical cavity surface emitting laser(VCSEL)ONU shows a maximum reduction in power consumption of 15.5 W and a 20%improvement in energy savings compared with the traditional fixed polling sequence.The MLASA method results in better power consumption with minimum delay than that of the proposed FILO and existing LASA methods.

Dynamic Wavelength and Bandwidth Allocation Using Adaptive Linear Prediction in WDM/TDM Ethernet Passive Optical Networks

Hybrid wavelength-division-multiplexing(WDM)/time-division-multiplexing(TDM) ethernet passive optical networks(EPONs) can achieve low per-subscriber cost and scalability to increase the number of subscribers. This paper discusses dynamic wavelength and bandwidth allocation(DWBA) algorithm in hybrid WDM/TDM EPONs.Based on the correlation structure of the variable bit rate(VBR) video traffic,we propose a quality-ofservice (QoS) supported DWBA using adaptive linear traffic prediction.Wavelength and timeslot are allocated dynamically by optical line terminal(OLT) to all optical network units(ONUs) based on the bandwidth requests and the guaranteed service level agreements(SLA) of all ONUs.Mean square error of the predicted average arriving rate of compound video traffic during waiting period is minimized through Wiener-Hopf equation.Simulation results show that the DWBA-adaptive-linear-prediction(DWBA-ALP) algorithm can significantly improve the QoS performances in terms of low delay and high bandwidth utilization.

Analysis and testing of total ionizing dose effect on several commercial optical transceivers via gamma-ray radiation

In our Lett er, we selec ted several commercial optical t ransceivers, which consist of single-channel transceiver modules, parallel transmitting and receiving modules, and Ethernet passive optical network (EPON) optical linet erminal (OLT) and optical net work unit (ONU) modules, to do the total ionizing dose (TID) testing via the gamma-ray radiation method. The changing of current and receiver sensitivity of optical transceivers is discussed and analyzed. Based on the TID testing exposed to a TID of 50 krad (Si) at a dose rate of about 0.1 rad (Si)/s, the performance of single-channel transceivers and parallel receiving modules has not changed after 50 krad (Si) exposure, the parallel transmitting and EPON ONU modules have not worked after 40 krad (Si) and 47 krad (Si) exposure, the EPON OLT module has bit error in the process of irradiation, and it can work well after annealing;the reason for the error of OLT is analyzed. Finally, based on the theoretical analysis and testing results, this Letter provides several design suggestions to improve the reliability for optical transceivers, which can be referenced by satellite system designation for various space missions.