Time Reversal Precoding at SubTHz Frequencies: Experimental Results on Spatiotemporal Focusing

Ali Mokh; Julien de Rosny; George C. Alexandropoulos; Ramin Khayatzadeh; Abdelwaheb Ourir; Mohamed Kamoun; Arnaud Tourin; Mathias Fink

arXiv · 2203.15322

Time Reversal Precoding at SubTHz Frequencies: Experimental Results on Spatiotemporal Focusing

Ali Mokh·Julien de Rosny·George C. Alexandropoulos·Ramin Khayatzadeh·Abdelwaheb Ourir·Mohamed Kamoun·Arnaud Tourin·Mathias Fink

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Abstract

Due to availability of large spectrum chunks, the sub-TeraHertz (subTHz) frequency band can support Ultra-WideBand (UWB) wireless communications, paving the way for unprecedented increase in the wireless network capacity. This fact is expected to be the next breakthrough for the upcoming sixth Generation (6G) standards. However, the technology of subTHz transceivers is not yet mature enough to apply the advanced signal processing currently being implemented for millimeter wave wireless communications. In this paper, we consider the Time Reversal (TR) precoding technique, which provides simple and robust processing capable to offer highly focalized in time and space UWB waveforms, exploiting the spatial diversity of wireless channels. We first investigate experimentally the performance of subTHz TR focusing in complex media inside a leaking reverberation cavity. We then combine TR with received spatial modulation to realize data communication using a simple non-coherent receiver with two antennas. Our results showcase the capability of TR to offer focusing in time in the order of few nanoseconds and in space in the order of less than 1 mm.

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Ali Mokh, Julien de Rosny, George C. Alexandropoulos, Ramin Khayatzadeh, Abdelwaheb Ourir, Mohamed Kamoun, Arnaud Tourin, Mathias Fink. 2022-03-29. Time Reversal Precoding at SubTHz Frequencies: Experimental Results on Spatiotemporal Focusing. https://arxiv.org/abs/2203.15322

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