Time-varying Bit Rate Routing Algorithm And Robust Routing Strategy In Wireless Sensor Networks

Different from traditional networks, wireless sensor networks(WSNs) are usually powered by batteries with limited energy, so the lifetime of wireless sensor networks has become a critical performance index. At the same time, in order to improve the quality of service in wireless sensor networks, the robustness of routing is also studied. The concrete research content is divided into two parts.(1) In the section we formulate the WSNs with a two-tier architecture, where the cluster head nodes partitioned into the upper tier are studied, and the routing problem is analyzed with the time-varying data rate, then a time-varying bit rate routing algorithm based on data fusion is proposed. If the mean value of varying data rate at a specific cluster head is known a priori, then the routing solution obtained by the proposed algorithm achieves maximal network lifetime. Further, we prove that the routing solution is optimal by applying the bit rate routing algorithm, and the simulation results validate the effectiveness.(2) We jointly integrate the maximization of network lifetime and the designing of robust routing strategy into consideration, by which both two sub-problems are modeled in a framework of cross-layer nonlinear optimization. By using the popular anti-risk methods popularly used in financial mathematics, our proposed cross-layer optimization problem can be transformed to a convex expression, while its uncertain probabilistic constraints are further changed to a specific solvable expression. Inspired by the particle swarm intelligence in recent development of evolutionary computation, a penalty function based method is introduced and applied in the optimal solution searching process. The effectiveness of our robust routing design is validated by the extensive simulation results, and the quantitative interactions among different neighboring links are also analyzed in a typical network topology.