Dynamic Connectivity in Wireless Underground Sensor Networks

In wireless underground sensor networks (WUSNs), due to the dynamic underground channel characteristics and the heterogeneous network architecture, the connectivity analysis is much more complicated than in the terrestrial wireless sensor networks and ad hoc networks, which was not addressed before, to our knowledge. In this paper, a mathematical model is developed to analyze the dynamic connectivity in WUSNs, which captures the effects of the environmental parameters such as the soil composition and the soil moisture, and the system parameters such as the operating frequency, the sensor burial depth, the sink antenna height, the density of the sensor and sink devices, the tolerable latency of the networks, and the number and the mobility of the above-ground sinks. The lower and upper bounds of the connectivity probability are derived to analytically provide principles and guidelines for the design and deployment of WUSNs in various environmental conditions.