An indoor optical wireless location comparison between an angular receiver and an image receiver

Abstract

In this work, the positioning accuracies of two novel photoreceivers are demonstrated. The two photoreceivers, namely an angular receiver and an image receiver, estimate their position via triangulation by measuring the angle of arrival (AOA) of light from LED optical beacons. The angular receiver consists of three PDs assembled in a corner-cube structure, while the image receiver consists of a custom-made microlens over top of a CMOS array image sensor. The mean AOA accuracy of the angular receiver was found to be 2° whereas the mean AOA accuracy of the image receiver was found to be 0.5°. The effect of LED optical beacon and photoreceiver geometry was quantified in terms of Dilution of Precision (DOP). The position accuracy of the photoreceivers was quantified while static and in motion. In the static case, the mean position accuracy of the angular receiver was found to be 5 cm whereas the mean position accuracy of the image receiver was found to be 2.5 cm. While the photoreceivers were in motion, the mean position accuracy of the angular receiver was found to be on the order of 10 cm whereas the mean position accuracy of the image receiver was found to be 4 cm.