Performance analysis and characterization of a Bluetooth 5.0 architecture for the mobility of visually impaired people

Abstract

Assistive technologies for visually impaired people (VIP) face critical wireless connectivity challenges in both urban and rural environments. This study presents the technological evolution of systems previously developed by the research group, transitioning from a radio frequency architecture within the ISM band to an architecture based on Bluetooth 5.0 technology. Unlike solutions dependent on network infrastructure, the proposed system relies on a decentralized four-module architecture (MASTER, BUS, STOP, and ETA), optimized for the autonomous navigation of VIP in public transport. The core of the research focuses on an experimental characterization of the propagation channel by monitoring and analyzing the stability of the Received Signal Strength Indicator (RSSI) and latency through Round-Trip Time (RTT). The results demonstrate that the Bluetooth 5.0 implementation, enhanced by the use of high-density integration microcontrollers, not only significantly reduces signal variance but also resulted in a reduction of more than 60% in the area of the implemented electronic boards. The integration of antennas into the PCB constitutes a critical aspect of the system design, as it influences cost reduction and increases robustness against multipath interference. The new system enables more precise localization and superior scalability, contributing to the improvement of inclusive mobility for VIP in limited connectivity environments.