为缓解基站的视频流量过载,本文针对时延敏感的实时视频业务,设计一种D2D协作视频多播传输方案。该方案采用可伸缩视频编码(Scalable Video Coding, SVC)对视频流进行编码处理,利用SVC流的分层结构特征来应对多播信道间的差异性。在SVC...为缓解基站的视频流量过载,本文针对时延敏感的实时视频业务,设计一种D2D协作视频多播传输方案。该方案采用可伸缩视频编码(Scalable Video Coding, SVC)对视频流进行编码处理,利用SVC流的分层结构特征来应对多播信道间的差异性。在SVC编码的基础上,为了改善用户观看体验及提升用户所接收的视频质量,所提出的协作式视频传输方案引入有效吞吐量这一概念,在一定时延约束下,根据信道反馈信息灵活地对不同信道上的不同SVC视频层进行码率调整。仿真结果表明,所提出的方案能够有效地减小端到端时延,有效丢失率,提高有效吞吐量。展开更多
Random Matrix Theory (RMT) is a valuable tool for describing the asymptotic behavior of multiple systems,especially for large matrices. In this paper,using asymptotic random matrix theory,a new cooperative Multiple-In...Random Matrix Theory (RMT) is a valuable tool for describing the asymptotic behavior of multiple systems,especially for large matrices. In this paper,using asymptotic random matrix theory,a new cooperative Multiple-Input Multiple-Output (MIMO) scheme for spectrum sensing is proposed,which shows how asymptotic free property of random matrices and the property of Wishart distribution can be used to assist spectrum sensing for Cognitive Radios (CRs). Simulations over Rayleigh fading and AWGN channels demonstrate the proposed scheme has better detection performance compared with the energy detection techniques even in the case of a small sample of observations.展开更多
文摘为缓解基站的视频流量过载,本文针对时延敏感的实时视频业务,设计一种D2D协作视频多播传输方案。该方案采用可伸缩视频编码(Scalable Video Coding, SVC)对视频流进行编码处理,利用SVC流的分层结构特征来应对多播信道间的差异性。在SVC编码的基础上,为了改善用户观看体验及提升用户所接收的视频质量,所提出的协作式视频传输方案引入有效吞吐量这一概念,在一定时延约束下,根据信道反馈信息灵活地对不同信道上的不同SVC视频层进行码率调整。仿真结果表明,所提出的方案能够有效地减小端到端时延,有效丢失率,提高有效吞吐量。
基金Supported by the National Natural Science Foundation of China (No.60972039)Natural Science Foundation of Jiangsu Province (No.BK2007729)Natural Science Funding of Jiangsu Province (No.06KJA51001)
文摘Random Matrix Theory (RMT) is a valuable tool for describing the asymptotic behavior of multiple systems,especially for large matrices. In this paper,using asymptotic random matrix theory,a new cooperative Multiple-Input Multiple-Output (MIMO) scheme for spectrum sensing is proposed,which shows how asymptotic free property of random matrices and the property of Wishart distribution can be used to assist spectrum sensing for Cognitive Radios (CRs). Simulations over Rayleigh fading and AWGN channels demonstrate the proposed scheme has better detection performance compared with the energy detection techniques even in the case of a small sample of observations.
