有限的节点能量和通信带宽,是AdHoc网络的两个重要的特点.节点能量是影响网络容量的关键因素,也是制约网络寿命的决定因素:而有限的通信带宽使得网络更容易产生拥塞.因此,节能型的功率控制与拥塞控制联合优化在AdHoc网络中显得尤为重要.首先,设计了节能型的网络效用最大化问题,即在目标函数中引入能量消耗成本函数,从网络效用和网络寿命两个方面来综合优化网络性能.其次,运用对偶分解与梯度投影方法,提出了相应的节能型功率控制与拥塞控制联合优化算法.另外,分析和证明了所提算法的收敛性.最后,详细的仿真结果表明了所提算法的有效性:在保持网络吞吐量基本不变的同时,可以有效地减少节点的能量消耗,从而延长网络寿命.
The limited energy of the node and the restricted communication bandwidths are two important features of ad hoc networks. The energy of the node is not only a key factor effecting network capacities, but is also a determinant factor in restricting network lifetime The limited communication bandwidth makes the network more prone to congestion. Hense, it is particular important to design a joint optimal congestion control and power control algorithm by providing energy saving in ad hoc networks. First, the study proposes a network utility maximization problem that provides energy saving, by introducing the cost function of energy consumption to the objective function of the network utility maximization problem, so the performance of the network can be optimized both in the network lifetime and network utility. Secondly, by the dual decomposition method and gradient projection method, the case proposes a joint power control and congestion control algorithm that provides energy saving to solve this problem. In addition, the project analyzes and verifies the convergence of the proposed algorithm. Finally, simulation results in detail are given to demonstrate the efficiency of the proposed algorithm. The network adapt the proposed algorithm can significantly reduce the energy consumption and prolong the network lifetime, while the remaining network throughput basically unchanged.