Antenna Polarization as Complementarities on RSSI Based Location Identification

Abstract

Pervasive computing applications, which are location-aware systems becoming increasingly important as part of our daily life. Real-time position localization of moving objects in an indoor environment is an encouraging technology for realizing the vision of creating numerous novel location-aware services and applications in various market segments. An off the shelf development platform that uses radio signal strength indication (RSSI) based location technique is always used for testing. In this paper we investigated at the affects of polarization on an indoor location tracking system. The target of this paper is to present an optimal design for RSSI location technology. We created a model for determining range form RSSI demonstrated that this model fits our experimental setup. Antenna polarization will affect RSSI and thus range accuracy. The experiments and its errors are carefully analyzed and found that the traditional least squares method of determining the parameters of the range model will give unacceptably high location error. A simple and cheap method of determining polarization angle is introduced with an accelerometer, which also increase the battery life of the node.