Enhancing the radio link quality of device-free localization system using directional antennas

Device-Free Localization (DfL) exploits the radio signal irregularities, hence can be used as an assistive technology to detect the moving entities, e.g. people, without the need for wearable devices. However, most of DfL systems employ omni-directional antennas, where the localization accuracy of these systems experienced the complex multipath propagation behavior. The directional micro-strip patch antennas have been implemented into the existing DfL system to observe the quality of radio link behavior and its effect to the human indoor localization accuracy. The performance of the proposed system has been evaluated and compared to the existing omni-directional attenuation-based DfL, which usually experienced the complex multipath propagation problem. Result shows that the proposed system was able to accurately detect a human presence in both static and moving scenarios, with a significant improvement in the quality of radio links behavior.