Interference Aware Heuristics to Optimize Power Beacons for Battery-less WSNs

Abstract

To achieve an infinite lifetime of sensing infrastructure in Internet-of-Things, battery-less wireless powered sensor networks (WPSNs) are an important step. The nodes in battery-less WPSNs harvest and store energy in super-capacitors from RF signal which are periodically transmitted by power beacons (PBs) or chargers. However, using multiple power chargers requires a focus on a crucial problem of interference. The sensor nodes which are covered by more than one power beacons become unreliable because of the overlapping signals from chargers since the overlap can be constructive or destructive. In this paper, we propose an algorithm to optimize the number and placement of power beacons such that interference can be reduced. The result shows that our proposed optimal power beacon location (OPBL) algorithm reduces interference in 60% of cases and also reduces data transmission time (DTT) by 30% in 24% of cases in comparison to the state-of-the-art.