Maximizing Barrier Coverage Lifetime with Mobile Sensors

TL;DR

This paper investigates strategies for mobile sensors to maximize barrier coverage lifetime, considering energy constraints and sensor mobility, and introduces algorithms and complexity results for fixed and variable sensing radii.

Contribution

It presents new parametric search algorithms for maximizing coverage lifetime and proves NP-hardness and approximation bounds for related problems.

Findings

Developed algorithms for fixed radii with predetermined sensor order

Proposed algorithms for sensors initially at barrier endpoints

Proved NP-hardness and approximation limits for variable radii with co-located sensors

Abstract

Sensor networks are ubiquitously used for detection and tracking and as a result covering is one of the main tasks of such networks. We study the problem of maximizing the coverage lifetime of a barrier by mobile sensors with limited battery powers, where the coverage lifetime is the time until there is a breakdown in coverage due to the death of a sensor. Sensors are first deployed and then coverage commences. Energy is consumed in proportion to the distance traveled for mobility, while for coverage, energy is consumed in direct proportion to the radius of the sensor raised to a constant exponent. We study two variants which are distinguished by whether the sensing radii are given as part of the input or can be optimized, the fixed radii problem and the variable radii problem. We design parametric search algorithms for both problems for the case where the final order of the sensors is predetermined and for the case where sensors are initially located at barrier endpoints. In contrast, we show that the variable radii problem is strongly NP-hard and provide hardness of approximation results for fixed radii for the case where all the sensors are initially co-located at an internal point of the barrier.