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arXiv · 1612.03194

Holography of Wi-Fi radiation

Philipp Holl·Friedemann Reinhard
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Abstract

Wireless data transmission systems such as WiFi or Bluetooth emit coherent light - electromagnetic waves with precisely known amplitude and phase. Propagating in space, this radiation forms a hologram - a two-dimensional wavefront encoding a three-dimensional view of all objects traversed by the light beam. Here we demonstrate a scheme to record this hologram in a phase-coherent fashion across a meter-sized imaging region. We recover three-dimensional views of objects and emitters by feeding the resulting data into digital reconstruction algorithms. Employing a digital implementation of dark field propagation to suppress multipath reflection we significantly enhance the quality of the resulting images.

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Philipp Holl, Friedemann Reinhard. 2017-05-05. Holography of Wi-Fi radiation. https://doi.org/10.1103/physrevlett.118.183901

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