Towards Prolonged Lifetime for Deployed Wireless Sensor Networks in Outdoor Environment Monitoring *
Wireless networking and advanced sensing technology have enabled the development of low cost, power efficient Wireless Sensor Networks (WSNs) that can be used in various application domains such as healthcare, military, and Outdoor Environment Monitoring (OEM). The main building blocks of WSNs are Sensor Nodes (SNs). This chapter proposes a jointly energy-efficient and k- fault-tolerant node deployment strategy for heterogeneous WSNs. Intensive simulations showed that jointly considering energy efficiency and fault-tolerance in node deployment can dramatically increase the network lifetime in OEM applications. To maintain these two objectives during the operation time, a certain number of Mobile Relay Nodes (MRNs) is used. To find the optimal positions of these MRNs, an optimization problem is formulated where the objective is to jointly minimize the total energy consumed and maximize the minimum residual energy. The chapter describes the communication model, the network architecture, and the lifetime model. All three models were tailored to suit OEM applications.