Approximation algorithms for the antenna orientation problem
Paper in proceedings, 2013

We consider the following Antenna Orientation Problem: Given a connected Unit Disk Graph (UDG) formed by n identical omnidirectional sensors, what is the optimal range (or radius) which is necessary and sufficient for a given antenna beamwidth (or angle) φ so that after replacing the omnidirectional sensors by directional antennae of beamwidth φ we can determine an appropriate orientation of each antenna so that the resulting graph is strongly connected? The problem was first proposed and studied in Caragiannis et al. [3] where they showed that the antenna orientation problem can be solved optimally for φ ≥ 8π/5, and is NP-Hard for φ < 2π/3, where there is no approximation algorithm with ratio less than √3, unless P = NP. In this paper we study beamwidth/range tradeoffs for the antenna orientation problem. Namely, for the full range of angles in the interval [0, 2π] we compare the antenna range provided by an orientation algorithm to the optimal possible for the given beamwidth. We employ the concept of (2,φ)-connectivity, a generalization of the well-known 2-connectivity, which relates connectivity in the directed graph to the best possible antenna orientation at a given point of the graph and use this to propose new antenna orientation algorithms that ensure improved bounds on the antenna range for given angles and analyze their complexity.

Connectivity

Directional Antenna

Beamwidth

Wireless Sensor Networks

Antenna Orientation Problem

Author

Evangelos Kranakis

Carleton University

F. MacQuarrie

Carleton University

Oscar Morales

Chalmers, Computer Science and Engineering (Chalmers), Networks and Systems (Chalmers)

Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics)

03029743 (ISSN) 16113349 (eISSN)

Vol. 8070 225-235

Subject Categories

Computer and Information Science

DOI

10.1007/978-3-642-40164-0_22

ISBN

9783642401633

More information

Latest update

9/6/2018 1