Combining of redundant signal strength readings for an improved RF localization in multipath indoor environments

Multipath signal fading is a fundamental problem when using received signal strength (RSS) readings as sensor for a range-based indoor localization. Redundant RF transceivers with a simultaneous use of spatial and frequency diversity enable a compensation of multipath fading effects for more precise distance and position estimations. A novel maximum probability combining technique for a sensor fusion of the RSS readings of up to eight redundant and decorrelated RF channels is proposed. Experimental results on a one-dimensional motion test track are used to evaluate the improved localization performance compared to a maximum signal combining and the accuracy of a position estimation without redundancy.