Análise de desempenho de um conjunto de antenas para direction finding utilizando bluetooth 5.1

Abstract

Bluetooth technology is widely used in proximity solutions. The direction finding is a feature incorporated in the Bluetooth technology specification 5.1, which allows us to develop solutions in asset tracking and monitoring with higher accuracy. The location of the devices is done in a multi-stage process, and two methods can be used for direction finding. The Angle of Arrival (AoA) method allows us to measure the angle of arrival of a signal, transmitted by another device, at a receiver containing an array of antennas. Similar to AoA, the Angle of Departure (AoD) method allows us to measure the angle of departure of a signal transmitted by a device containing an array of antennas at a single antenna receiver. The antenna is a crucial part of any implementation with Bluetooth technology, its choice must be made aiming to meet some requirements to get the best possible performance, it must have high accuracy, high sensitivity, sufficient immunity to noise, polarization errors and multipath propagation. Given the lack of studies on the performance of antennas intended for direction finding in indoor localization systems, this work will develop a hardware platform with its respective firmware, in order to compare the performance of an antenna array. The direction finding method to be used is Angle of Arrival, so we will work only in two dimensions to find the angle from the receiver plane. With the results, discussions and conclusions of this work, it is expected to contribute with a study aimed at analyzing the performance of the antennas used in solutions that make use of the direction finding resource.