V-shape liquid crystal-based retromodulator air to ground optical communications

Morten. A. Geday; Guillermo del Campo; Alberto Carrasco-Casado; Noureddine Bennis; Xabier Quintana; Francisco Lopez Hernandez; Jose Manuel Oton Sanchez

doi:10.1080/15421400802430299

arXiv · 1512.01543

V-shape liquid crystal-based retromodulator air to ground optical communications

Morten. A. Geday·Guillermo del Campo·Alberto Carrasco-Casado·Noureddine Bennis·Xabier Quintana·Francisco Lopez Hernandez·Jose Manuel Oton Sanchez

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Abstract

This paper describes the use of a 2D liquid crystal retro-modulator as a free space, wireless, optical link. The retro-modulator is made up of a retro-reflecting cornercube onto which 2 cascaded V-shape smectics liquid crystal modulators are mounted. The communication link differs with respect to more conventional optical links in not using amplitude (nor frequency) modulation, but instead state-of-polarisation (SOP) modulation known as Polarisation Shift Keying (PolSK). PolSK has the advantage over amplitude modulation, that it is less sensitive to changes in the visibility of the atmosphere, and increases inherently the bandwidth of the link. The implementation of PolSK both in liquid crystal based and in retro-modulated communication are novelties.

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Morten. A. Geday, Guillermo del Campo, Alberto Carrasco-Casado, Noureddine Bennis, Xabier Quintana, Francisco Lopez Hernandez, Jose Manuel Oton Sanchez. 2015-06-26. V-shape liquid crystal-based retromodulator air to ground optical communications. https://doi.org/10.1080/15421400802430299

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