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arXiv · 2109.09465

Analog FM free-space optical communication based on a mid-infrared quantum cascade laser frequency comb

Nicola Corrias·Tecla Gabbrielli·Paolo De Natale·Luigi Consolino·Francesco Cappelli
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Abstract

Quantum cascade laser frequency combs are nowadays well-appreciated sources for infrared spectroscopy. Here their applicability for free-space optical communication is demonstrated. The spontaneously-generated intermodal beat note of the frequency comb is used as carrier for transferring the analog signal via frequency modulation. Exploiting the atmospheric transparency window at 4 $\mu$m, an optical communication with a signal-to-noise ratio up to 65 dB is realized, with a modulation bandwidth of 300 kHz. The system tolerates a maximum optical attenuation exceeding 35 dB. The possibility of parallel transmission of an independent digital signal via amplitude modulation at 5 MS/s is also demonstrated.

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Nicola Corrias, Tecla Gabbrielli, Paolo De Natale, Luigi Consolino, Francesco Cappelli. 2021-09-14. Analog FM free-space optical communication based on a mid-infrared quantum cascade laser frequency comb. https://doi.org/10.1364/oe.443483

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