FPGA-Based Architecture for Managing Ultrasonic Beacons in a Local Positioning System

During past decades, local positioning systems (LPSs) have become more and more important for different robotic and automation applications, as well as for service-oriented developments. One of the emerging technologies for that purpose is ultrasounds, since they provide positioning errors in the range of centimeters with low-cost deployments. Nevertheless, they present some drawbacks, which constrain their use and spreading. The performance of ultrasonic LPS (ULPS) can be significantly enhanced by applying encoding techniques to ultrasonic transmissions. The use of encoding techniques and the deployment of multiple beacon units require the availability of more sophisticated control modules capable of carrying out a suitable configuration of the system operation and processing the ultrasonic transmissions in these complex environments. In this way, this paper presents the design of a system in charge of managing a beacon unit used for the deployment of ULPS in wide spaces. The design consists of a system-on-chip architecture based on a field-programmable gate array device. The proposed system allows the flexible run-time configuration of a beacon unit in terms of the data to be transmitted and the bandwidth and frequencies used. The design has been successfully validated in an ULPS installed in a highly complex environment, where a robot has been correctly positioned during navigation.