Improving an IEEE 802.15.4 Based Direction of Arrival Estimation System Reliability in a Real Case Scenario Exploiting a Smart Multichannel Approach

This manuscript presents a novel method to enhance phaseless Direction of Arrival (DoA) estimation reliability in real case indoor scenarios by the means of channel hopping, supported by the exploited wireless standard (IEEE 802.15.4). The use of multiple channels allows for a change in the electromagnetic environment seen by both the anchor and the target node, thus improving the resistance against deterministic but untraceable non idealities such as the multi-path. The DoA estimation is based on a maximum likelihood (ML) criteria applied to the data coming from a Switched Beam Antenna (SBA) capable of space partitioning thanks to the diagram patterns of its elements. To realistically mimic a real case scenario, the antenna of the target is a Planar Inverted-F Antenna (PIFA) characterized by strong non idealities, such as a diagram pattern widely changing from one channel to the others. The experimental validation confirms the higher reliability of the multichannel method with respect to the single channel with numerical results.