DoA estimation with a single antenna and a few low-cost backscattering tagsDoA estimation with a single antenna and a few low-cost backscattering tags Peer-Reviewed Journal Publication Δημοσίευση σε Περιοδικό με Κριτές 2023-11-092022enThe research work was supported by the Hellenic Foundation for Research and Innovation (H.F.R.I.) under the “First Call for H.F.R.I. Research Projects to support Faculty members and Researchers and the Procurement of High-cost research equipment” (Project Number: 2846).An earlier version of this paper was presented in part at the IEEE International Conference on Acoustics, Speech and Signal Processing (ICASSP), Toronto, ON, Canada, June 2021, [DOI: 10.1109/ICASSP39728.2021.9414918].Backscatter radio utilizes the reflection that an electromagnetic wave undergoes when it impinges an unmatched-to-a-load antenna, in order to achieve ultra-low-power communication. This work exploits principles commonly found in the ultra-low-power, backscatter communication literature, offering multi-element array functionalities to a single-antenna receiver. A small number of simple, switching backscattering tags deployed in space, emulate a distributed, multi-element antenna array by copying a transmitter’s signal to distinct frequency bands. A receiver can then obtain independent observations of the same signal by discriminating said bands. Using the backscatter tag-based array, the direction of arrival (DoA) estimation problem is addressed without the cost of multiple RF front ends or hardware modifications, at either end of a wireless communication link. The feasibility of the idea was examined through both simulations and experimental deployments. An absolute error of ≈20 degrees was observed when utilizing 5 custom-built backscattering tags, while simulations showed that more than 10 tags can offer error of less than 5 degrees.http://creativecommons.org/licenses/by/4.0/IEEE Transactions on Communications70106849-6860 Vougioukas Georgios Βουγιουκας Γεωργιος Bletsas Aggelos Μπλετσας Αγγελος Institute of Electrical and Electronics Engineers Backscatter radio Direction of arrival estimation Antenna arrays