Accurate Positioning Based on a Combination of Power Attenuation and a Signal Strength Indicator Using Active RFID Technology

The aim of this paper is to develop a new positioning technique to assist the blind and people with low vision to indicate their locations and reach their destinations. The presented technique is based on a combination of power level and Signal Strength Indicator (SSI) using active Radio Frequency Identification RFID technology. The system uses a mobile reader with power attenuation feature. SSI is used as a distance estimator for short range and in combination with one of eight receiver attenuation level sittings for a wider range of up to 70 meters. Global Positioning System (GPS) works efficiently in a similar environment but is only accurate to around ten to twenty meters and it does not work efficiently at indoor environments. This research has produced an identification localization system which identifies various locations such as offices, labs, theaters and so on to assist users reach their destination of interest. Then it has been conducted as a real empirical case study to identify labs base on a combined technique with a successful identification rate of around 98%. The reader has eight attenuation settings, and the geographic range of each level using various tags has been calculated. Then, to evaluate reliability 108 experiments were conducted using three tags with distances from 1 metre to 25 metres using power settings 1 to 6. A successful detection rate of 93.5% was achieved, as well as a false positive rate of 1%.