Water–Bomb Origami Phased Array with Integrated SWIPT for Battery–Free IoT Node

This paper presents a novel origami-based phased-array antenna that integrates simultaneous wireless information and power transfer for battery-free Internet-of-Things nodes. Water-bomb tessellation enables mechanical beam steering by folding the aperture from a planar sheet into an inverted dome geometry. As a proof-of-concept, a <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$2 \times 2$</tex> array simulated results show that the folded state increases the beamwidth from 30.6° to 61.3° at 2.45 GHz and reduces the realized gain from 13.7 dBi to 10.5 dBi. Each patch element incorporates a single-diode rectifier, achieving <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$3.6 \mu \mathrm{W}$</tex> of harvested power per element during 0.85 m over-the-air data reception with 1 Mbps BPSK modulation.