A tree-based approach to design Heterogeneous Sensor Networks based on small world concepts

A typical Wireless Sensor Network (WSN) assumes a homogeneous set of nodes in terms of capabilities. However, this kind of network suffer from poor fundamental limits of latency during the data communication. Another model of WSN assumes a heterogeneous set of nodes with different capabilities (especially in terms of communication range and energy reserves) called Heterogeneous Sensor Networks (HSNs). In this work, we propose a tree-based approach based on small world concepts to design HSNs. The proposed model introduces an adjustable search space in order to find H-sensors to create shortcuts between them. The endpoints of these shortcuts are nodes with more powerful communication range and energy reserves to support the long communication range. The model was designed in such a way that the created shortcuts among the powerful nodes create a connected topology among them. As a consequence of this, it is not necessary that the nodes with lower capabilities forward messages as a bridge to interconnect the shortcuts. Simulation results showed that with just a few powerful nodes, a wireless sensor network can be tuned into a HSN with small world features. Also, when the shortcut addition creates a connected topology among the H-sensors, the data communication latency is significantly reduced.