RSSI Based Localization of Bluetooth Devices Using Trilateration: An Improved Method for the Visually Impaired

摘要

The instantaneous and spatial localization for visually impaired people in dynamically changing environments with unexpected hazards and obstacles, is the most demanding and challenging issue faced by the navigation systems today. Although time difference of arrival (TDOA), time of arrival (TOA) and received signal strength (RSS) have been used in literature multiple times for positioning, but narrow band signals such as Bluetooth cannot efficiently utilize TDOA or TOA. Received signal strength indicator (RSSI), to measure RSS, has been found to be more suitable in this case. It has been found that the estimations using RSSI can be improved significantly by improving the existing methodologies related to RSSI. Therefore, the current paper focuses on proposing an improved method using trilateration for localization of Bluetooth devices for visually impaired people. To validate the method, class 2 Bluetooth devices were used along with the development of a software. Experiments were then conducted to obtain surface plots that showed the signal interferences and other environmental effects. Finally, the results obtained were discussed.