A time-dependent link failure model for wireless sensor networks

Wireless links are one of the primary performance-limiting factors in wireless sensor networks (WSNs). In particular, link failures negatively influence the network performance, reliability, and availability in most cases. In WSNs, a link failure might result in the loss of the shortest path between a sensor node and the sink node; thus the data will have to be transmitted via a longer path, leading to longer transmission delay and increased energy consumption. Therefore, it is crucial to characterize the impact of different parameters, such as battery life-time, power consumption of sensor nodes, fading, and interference, on wireless links. The main contribution of this work is the introduction of a time-dependent link failure model that incorporates the consideration of battery discharge model, sensor node power consumption in different modes, and wireless channel conditions (shadowing, background noise and interference). Furthermore, effects of the proposed link failure model on application communication reliability, network coverage, network topology, and energy consumption of delivering sensed data to sink node using different routing protocols are studied. Experimental results show that WSNs using the shortest-path distance algorithm are typically more reliable than those using the shortest-path hop algorithm, but they typically consume more energy for communication.