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Multi-kilometre and multi-gigabit-per-second sub-terahertz communications for wireless backhaul applications

Abstract

Sub-terahertz- and terahertz-band—that is, from 100 GHz to 10 THz—communication technologies will be required for next-generation (6G and beyond) wireless communication networks. Considerable progress has been made in terahertz device technology for personal and local area networks, but there are many applications that could benefit from the large capacity of sub-terahertz and terahertz wireless links if longer communication distances were possible. The generation of high-power information-bearing ultrabroadband signals for long-distance communication is though challenging. Here we report a multi-kilometre and multi-gigabit-per-second link operating at 210–240 GHz. We use on-chip power-combining frequency multiplier designs based on Schottky diode technology to achieve a transmit power of 200 mW. A tailored software-defined ultrabroadband digital signal processing back end is also used to generate the modulated signal and process it in the receiver.

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Fig. 1: Experimental setup and system design at 210–240 GHz.
Fig. 2: Transmitter and receiver performance at 210–240 GHz.
Fig. 3: Frame definition and its transition from the transmitter to receiver at various stages.
Fig. 4: Front-end characterization and performance of the 2 km link.
Fig. 5: JPL’s high-power multiplier and detailed front-end system design with capabilities.

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Data availability

The data corresponding to the raw received signals at the IF for the different configurations shown in Table 1 are available from the corresponding author upon request. Because the experiments were conducted at the US Air Force Research Laboratory (AFRL) Information Directorate’s Newport Research facilities, as indicated in the manuscript, a Cooperative Research and Development Agreement or memorandum of understanding is needed between the requester’s organization, authors’ organization and/or sponsoring organization, which in this case is the US Air Force Research Laboratory AFRL. To obtain such an agreement, please contact the corresponding author, who will guide the requester through the necessary steps. Source data are provided with this paper.

Code availability

The codes utilized for the generation of the signals at the transmitter and for the processing of the measured signals at the receiver. Because the experiments were conducted at the US AFRL Information Directorate’s Newport Research facilities, as indicated in the manuscript, a Cooperative Research and Development Agreement or memorandum of understanding is needed between the requester’s organization, authors’ organization and/or sponsoring organization, which in this case is the US AFRL. To obtain such an agreement, please contact the corresponding author, who will guide the requester through the necessary steps.

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Acknowledgements

P.S. and J.M.J. were supported in part by the US Air Force Research Laboratory grant FA8750-20-1-0200 and the US National Science Foundation grant CNS-2011411. J.V.S. was supported by the US Air Force Research Laboratory (AFRL) and JPL Advance Concept Funds program. We would like to acknowledge K. Gross (US Air Force) and AFRL interns, C. Bosso, J. Hall and C. Slezak, for help during data collection of the project. We would like to thank J. Heinig, AFRL Newport Research Facilities manager and the PAR Government Systems Corporation team led by J. Wille and D. Overrocker who helped us with the test setup, coordination and antenna mount fabrication during our experiment at Newport Research Facilities. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of AFRL. Approved for Public Release; Distribution Unlimited: AFRL-2022-5484.

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All the authors contributed to the problem definition, conceived and designed the experiments, analysed the data, contributed materials and wrote the paper.

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Correspondence to Priyangshu Sen, Jose V. Siles, Ngwe Thawdar or Josep M. Jornet.

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Sen, P., Siles, J.V., Thawdar, N. et al. Multi-kilometre and multi-gigabit-per-second sub-terahertz communications for wireless backhaul applications. Nat Electron 6, 164–175 (2023). https://doi.org/10.1038/s41928-022-00897-6

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