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arXiv · 2005.00807

Space-Time Medium Functions as a Perfect Antenna-Mixer-Amplifier Transceiver

Sajjad Taravati·George V. Eleftheriades
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Abstract

We show that a space-time-varying medium can function as a front-end transceiver, i.e., an antenna-mixer-amplifier. Such a unique functionality is endowed by space-time surface waves associated with complex space-time wave vectors in a subluminal space-time medium. The proposed structure introduces pure frequency up- and down-conversions and with very weak undesired time harmonics. In contrast to other recently proposed space-time mixers, a large frequency up-/down conversion ratio, associated with gain is achievable. Furthermore, as the structure does not operate based on progressive energy transition between the space-time modulation and the incident wave, it possesses a subwavelength thickness (metasurface). Such a multi-functional, highly efficient and compact medium is expected to find various applications in modern wireless telecommunication systems.

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Sajjad Taravati, George V. Eleftheriades. 2020-05-02. Space-Time Medium Functions as a Perfect Antenna-Mixer-Amplifier Transceiver. https://doi.org/10.1103/physrevapplied.14.054017

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