In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discr...In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discrete linear system with state and control constraints. Then we apply the discrete maximum principle to get the optimal solution. Experimental results are given in the end. Compared with traditional algorithms, the proposed algorithm is suitable for the coder with continuous output rates, and can achieve the better solution. Our algorithm can be used in both off-line and on-line coding.展开更多
随着无线传感网技术的快速发展以及它自身的标准要与互联网共存的需要,6LOWPAN应运而生。6LOWPAN性能参数包括能量消耗,传输时延,接收信号强度指示和丢包率等。通过实施具体的实验分析得出IEEE802.15.4信道选择影响数据传输时间。节点...随着无线传感网技术的快速发展以及它自身的标准要与互联网共存的需要,6LOWPAN应运而生。6LOWPAN性能参数包括能量消耗,传输时延,接收信号强度指示和丢包率等。通过实施具体的实验分析得出IEEE802.15.4信道选择影响数据传输时间。节点个数和有无恒定比特率(CBR,Concurrent Constant Bit Rate)则会改变网络通信量,能量消耗等性能指标值。深入探讨了各种参数对6LOWPAN性能的影响,主要研究了IEEE802.15.4信道选择以及恒定比特率的作用。通过硬件和软件实验也证明了信道选择26时网络性能最好。展开更多
文摘In this paper we discuss the source rate control problem of adapting variable bit-rate （VBR） compressed video over constant bit-rate （CBR） channels. Firstly we formulate it as an optimal control problem of a discrete linear system with state and control constraints. Then we apply the discrete maximum principle to get the optimal solution. Experimental results are given in the end. Compared with traditional algorithms, the proposed algorithm is suitable for the coder with continuous output rates, and can achieve the better solution. Our algorithm can be used in both off-line and on-line coding.
文摘随着无线传感网技术的快速发展以及它自身的标准要与互联网共存的需要,6LOWPAN应运而生。6LOWPAN性能参数包括能量消耗,传输时延,接收信号强度指示和丢包率等。通过实施具体的实验分析得出IEEE802.15.4信道选择影响数据传输时间。节点个数和有无恒定比特率(CBR,Concurrent Constant Bit Rate)则会改变网络通信量,能量消耗等性能指标值。深入探讨了各种参数对6LOWPAN性能的影响,主要研究了IEEE802.15.4信道选择以及恒定比特率的作用。通过硬件和软件实验也证明了信道选择26时网络性能最好。
