Driven by an ever-increasing num- ber of new services and applications, transport networks have been undergoing significant changes. In this paper, we describe several ex- citing technology directions associated with ...Driven by an ever-increasing num- ber of new services and applications, transport networks have been undergoing significant changes. In this paper, we describe several ex- citing technology directions associated with future optical transport networks. We review the status of 100G, which is now commercially available and entering volume deployments, and its applications in China. Beyond 100G is considered as the primary technology for the expansion of both channel and fiber capacity in tile near term, and several enabling techniques are introduced. Then, key technologies, prod- ucts, and future evolutionary options of Optical Transport Networks (OTNs) are extensively discussed. Compared to fixed bandwidth and coarse granularity of current WDM network, a flexible grid architecture is a desirable evolu- tion trend, and key technologies and challenges are described. Finally, we illustrate the multi-dimension convergences in terms of IP and optical, Packet OTN (P-OTN), as well as Electronic Integrated Circuits (EICs) and Photonic Integrated Cimuits (PICs). Transport networks are therefore in the process of be- coming more broadband, robust, flexible, cost-effective and lower-power-consumptive.展开更多
Two-way decode-and-forward(DF) relay technique is an efficient method to improve system performance in 5G networks.However,traditional orthogonal frequency division multiplexing(OFDM) based two-way relay systems only ...Two-way decode-and-forward(DF) relay technique is an efficient method to improve system performance in 5G networks.However,traditional orthogonal frequency division multiplexing(OFDM) based two-way relay systems only consider a per-subcarrier relay strategy,which treats each subcarrier as a separate channel,which results in significant sum rate loss,especially in fading environments.In this paper,a joint coding scheme over multiple subcarriers is involved for multipair users in two-way relay systems to obtain multiuser diversity.A generalized subcarrier pairing strategy is proposed to permit each user-pair to occupy different subcarriers during the two transmission phases,i.e.,the multiple access and broadcast phases.Moreover,a low complexity joint resource allocation scheme is proposed to improve the spectrum efficiency with an additional multi-user diversity gain.Some numerical simulations are finally provided to verify the efficacy of our proposal.展开更多
This paper divides the vertex set into several disjoined subsets and provides an optimal fault-tolerance routing algorithm based on the vertex set partition. This algorithm is efficient and convergent, in polynomial t...This paper divides the vertex set into several disjoined subsets and provides an optimal fault-tolerance routing algorithm based on the vertex set partition. This algorithm is efficient and convergent, in polynomial time, we can get the output if the vertex is given.展开更多
基金supported by the National Natural Science Foundation of China under GrantNo. 61171076National 863 Project underGrant No. 2012AA011303National 973 Project under Grant No. 2010CB328200(2010CB328201)
文摘Driven by an ever-increasing num- ber of new services and applications, transport networks have been undergoing significant changes. In this paper, we describe several ex- citing technology directions associated with future optical transport networks. We review the status of 100G, which is now commercially available and entering volume deployments, and its applications in China. Beyond 100G is considered as the primary technology for the expansion of both channel and fiber capacity in tile near term, and several enabling techniques are introduced. Then, key technologies, prod- ucts, and future evolutionary options of Optical Transport Networks (OTNs) are extensively discussed. Compared to fixed bandwidth and coarse granularity of current WDM network, a flexible grid architecture is a desirable evolu- tion trend, and key technologies and challenges are described. Finally, we illustrate the multi-dimension convergences in terms of IP and optical, Packet OTN (P-OTN), as well as Electronic Integrated Circuits (EICs) and Photonic Integrated Cimuits (PICs). Transport networks are therefore in the process of be- coming more broadband, robust, flexible, cost-effective and lower-power-consumptive.
基金supported by the National Natural Science Foundation of China(NSFC)(No.61501527)State’s Key Project of Research and Development Plan(No.2016YFE0122900-3)+1 种基金the Fundamental Research Funds for the Central Universities,Basic Research Foundation of Science Technology and Innovation Commission of Shenzhen Municipality(No.JCYJ20150630153033410)SYSU-CMU Shunde International Joint Research Institute and 2016 Major Project of Collaborative Innovation in Guangzhou(Research and Application of Ground Satellite Communicaiton Systems for Space Broadband Information Networks)
文摘Two-way decode-and-forward(DF) relay technique is an efficient method to improve system performance in 5G networks.However,traditional orthogonal frequency division multiplexing(OFDM) based two-way relay systems only consider a per-subcarrier relay strategy,which treats each subcarrier as a separate channel,which results in significant sum rate loss,especially in fading environments.In this paper,a joint coding scheme over multiple subcarriers is involved for multipair users in two-way relay systems to obtain multiuser diversity.A generalized subcarrier pairing strategy is proposed to permit each user-pair to occupy different subcarriers during the two transmission phases,i.e.,the multiple access and broadcast phases.Moreover,a low complexity joint resource allocation scheme is proposed to improve the spectrum efficiency with an additional multi-user diversity gain.Some numerical simulations are finally provided to verify the efficacy of our proposal.
基金This project is supported by National Natural Science Foundation of Chins (10371049) and Science Foundation of Three Gorges University
文摘This paper divides the vertex set into several disjoined subsets and provides an optimal fault-tolerance routing algorithm based on the vertex set partition. This algorithm is efficient and convergent, in polynomial time, we can get the output if the vertex is given.