Cross Layer Optimization for Energy-Constrained Wireless Sensor Networks: Joint Rate Control and Routing

In the following paper, we study the tradeoff between network utility and network lifetime for energy-constrained wireless sensor networks (WSNs). By introducing a weighted factor, we combine these two objectives into a single weighted objective, and we consider rate control and routing in this tradeoff framework simultaneously. First, by using a dual decomposition method, we decompose the tradeoff model into two subproblems: the congestion control/routing problem and the network lifetime problem, both of which interact through the dual variables for energy dissipation constraints. Based on the decomposition results, we propose a fully distributed algorithm to solve these two sub-problems and the dual problem by using gradient and sub-gradient projection methods. Second, we propose a fully distributed algorithm by approximating the network lifetime maximization problem by using the network utility maximization (NUM) framework. Third, we extend our distributed algorithm to deal with reliable communication and the real-time requirement. Rigorous analysis and simulations are presented to validate our algorithms.