Directional Virtual Coordinate Systems for Wireless Sensor Networks

A Directional Virtual Coordinate System (DVCS) is proposed based on a novel transformation that restores the lost directionality information in a Virtual Coordinate System (VCS). VCS is an attractive option to characterize the node locations in Wireless Sensor Networks (WSNs), instead of using geographical coordinates, which is expensive or difficult to obtain. A VCS characterizes each node in a network with the minimum hop distances to a set of anchor nodes as its coordinates. The proposed transformation supplements the virtual coordinates, thus preserving all the inheriting properties such as embedded information of geodesic distances in the coordinates. The virtual directionality introduced, alleviates the local minima issue present in original VCS. Properties of this virtual directional domain are discussed. With these directional properties, it is possible, for the first time, to consider deterministic algorithms in the virtual domain, as illustrated with a constrained tree network example. A novel routing scheme called Directional Virtual Coordinate Routing (DVCR), which illustrates the effectiveness of the Directional Virtual Coordinate domain is proposed. DVCR significantly outperforms existing VCS routing schemes Convex Subspace Routing (CSR) and Logical Coordinate Routing (LCR), while achieving a performance similar to the geographical routing scheme - Greedy Perimeter Stateless Routing (GPSR), but without the need for node location information.