Modified Hilbert Space-Filling Curve for Ellipsoidal Coverage in Wireless Ad Hoc Sensor Networks

Sensor nodes are deployed to sense an environment for observing the physical world. The sensing field (an area of interest) can be represented as an ellipse. This paper proposes an algorithm for covering an elliptical shaped area of interest within wireless sensor network fields by modifying the Hilbert-space filling curve. Conventionally, an area is partitioned into 2ⁿ times 2ⁿ square grid (Hilbert cells). Hilbert space-filling curve is modified to map only specific area of interest. To cover the entire area of interest, the algorithm requires a mobility pattern for a sink node in order to collect data for a specific mission. This is done by traversing the area from an entry point and finishing at an exit point from the square grids. Simulation results show that modified Hilbert space-filling curve achieves its best Hilbert-covering for an ellipse that is almost circular as opposed to a narrow ellipse.