DoA estimation of a hidden RF source exploiting simple backscatter radio tags

Conventional direction of arrival (DoA) techniques employ multi-antenna receivers with increased complexity and cost. This work emulates a multi-antenna system using a singleantenna receiver and exploiting the beauty and simplicity of backscatter radio. More specifically, a number of simple backscatter radio tags offer copies of the hidden RF source, relayed in space and shifted in frequency, while requiring minimal time-synchronisation. DoA of a hidden RF source was estimated with an error of less than 5 degrees, exploiting a small number of simple, ultra-low-cost backscattering tags.