【作者】 赵凯；

【导师】 郭磊；

【作者基本信息】 东北大学 ， 信号与信息处理， 2015， 硕士

【摘要】 近年来,互联网日新月异不断发展和创新,高带宽需求的业务呈现爆炸式增长趋势,如何促进下一代网络向高带宽、高速率和低能耗的方向发展成为学术界和工业界共同关注的焦点。作为一种新型的宽带接入技术,正交频分复用-无源光网络(Orthogonal Frequency Division Multiplexing-Passive Optical Network,OFDM-PON)不仅能通过多址接入方式提供多用户的高效灵活接入,而且允许时域和频域内的二维资源联合调度,进而实现带宽按需灵活分配。因此,OFDM-PON被公认为下一代宽带接入的理想技术之一。尽管OFDM-PON系统能提供较高的带宽利用率和信息传输速率,随之而来的高能耗、低能效等新问题却严重制约了网络规模和服务能力的可扩展性。因此,OFDM-PON中能效带宽分配算法的研究对建设绿色通信网络有着极其重要的理论意义和应用价值。本文聚焦OFDM-PON系统中能效型带宽分配算法的研究,针对以往研究中普遍存在的片面关注系统吞吐量或带宽利用率却忽视了带宽分配过程中的高能耗或能耗模型考虑不完善等典型问题,提出了全面的能效带宽分配机制,目的是为OFDM-PON系统未来的建设和发展提供丰富的理论指导和技术参考。首先,依据OFDM-PON中主要耗能部件光网络单元(Optical Network Unit,ONU)的工作状态对网络能耗的影响,提出基于ONU休眠模式的三维动态带宽分配算法(Three-Dimensional Dynamic Bandwidth Allocation,3D-DBA),通过时隙、载波和比特的三维带宽资源分配,在保证业务的误码率和ONU带宽需求的前提下,最小化OFDM-PON系统中业务相关能耗和业务无关能耗;其次,依据链路速率对能耗的影响,提出基于自适应链路速率和ONU休眠的混合节能动态带宽分配算法(Hybrid Energy-saving Dynamic Bandwidth Allocation,HE-DBA),在保证业务误码率和ONU带宽需求的基础上,通过混合节能机制,进一步降低OFDM-PON中业务无关能耗。本文通过VC++ 6.0软件搭建仿真平台,对所提出的算法进行了仿真实验和性能评估,并与以往研究中能效带宽分配算法进行了比较分析。结果表明,文中提出的3D-DBA和HE-DBA算法在降低网络能耗方面具有显著优势。更多还原

【Abstract】 In recent years,the Internet changes rapidly with continuous development and innovation,meanwhile the traffic which requires high bandwidth presents explosive growth trend.Therefore,how to promote the development of next-generation network to the direction of high bandwidth,high rate and low energy consumption has become the focus in the academic and industrial communities.As a new kind of broadband access technology,Orthogonal Frequency Division Multiplexing-Passive Optical Network(OFDM-PON)not only supports highly efficient and flexible access among multi-users through multiple accesses,but also allows united scheduling between time domain and frequency domain,achieving elastic bandwidth allocation according to the bandwidth requirement.Therefore,OFDM-PON is recognized as one of the most promising technologies of next-generation broadband access.OFDM-PON system can provide higher bandwidth utilization and higher rate of information transmission compared with conventional PON systems.However,with the new problems emerging such as higher energy consumption and lower energy efficiency,the extensible capacity of network scale and traffic ability are seriously restricted.As a result,the research of energy efficient dynamic bandwidth allocation algorithm in OFDM-PON takes theoretical and practical significance for the development of green communication network.This thesis focuses on the research of energy efficient dynamic bandwidth allocation algorithm in OFDM-PON system.In previous works,some researchers have paid one-sided attention to improving system throughput or bandwidth utilization,even ignoring high energy consumption in the process of bandwidth allocation,and other researchers have considered imperfect model of energy consumption.To solve these challenging problems,we propose two comprehensive enegy efficient bandwidth allocation schemes.Firstly,according to the energy consumption that is influedced by the operation state of Optical Network Unit(ONU)which is the primary component of energy consumption in network,we propose the Three-Dimensional Dynamic Bandwidth Allocation based on ONU sleep mode(3D-DBA).In 3D-DBA,we deal with the three dimension bandwidth resource allocation,which includes time slot,subcarrier and bit allocation.We optimize the energy consumption of traffic related and traffic unrelated in OFDM-PON system.Meanwhile,the performance of bit error ratio(BER)of traffic and bandwidth requirements of each ONU should be guaranteed.Secondly,we further propose the Hybrid Energy-saving Dynamic Bandwidth Allocation based on adaptive link rate and ONU sleep mode(HE-DBA)in accordance with the energy consumption which is influenced by link rate.In HE-DBA,we deal with the hybrid energy-saving scheme.Our objective is to further minimize the energy consumption of traffic unrelated while guaranteeing the ’bit error ratio of traffic and bandwidth requirements of each ONU.The VC++ 6.0 software is employed to develop the simulation platform in order to make simulation experiment and evaluate the performance of proposed algorithms.A comparative analysis is made between the proposed algorithms and the previous algorithms.Simulation results demonstrate that the proposed 3D-DBA and HE-DBA algorithms gain the obvious advantages in reducing the energy consumption of OFDM-PON system,which may provide abundant theoretical guidelines and technological references for the development of OFDM-PON system in future.更多还原