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Abstract A key challenge in millimeter-wave and terahertz wireless networks is blockage of the line-of-sight path between a base station and a user. User and environmental mobility can lead to blockage of highly directional beams by intervening people or objects, yielding link disruptions and poor quality of service. Here, we propose a solution to this problem which leverages the fact that, in such scenarios, users are likely to be located within the electromagnetic near field of the base station, which opens the possibility to engineer wave fronts for link maintenance. We show that curved beams, carrying data at high bit rates, can realize a link by curving around an intervening obstacle. We develop a model to analyze and experimentally evaluate the bandwidth limitations imposed by the use of self accelerating beams. We also demonstrate that such links employ the full aperture of the transmitter, even those portions which have no direct line of sight to the receiver, emphasizing that ray optics fails to capture the behavior of these near-field wave fronts. This approach, which is ideally suited for use at millimeter-wave and terahertz frequencies, opens vast new possibilities for wave front management in directional wireless networks.
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Ultrabroadband terahertz-band communications with self-healing bessel beams
Abstract The large available bandwidth at sub-terahertz and terahertz frequencies has the potential to enable very high data rates for wireless communications. Moreover, given the large electrical size of terahertz antenna apertures, many future terahertz communication systems will likely operate in the near field. However, due to their reliance on highly directional beams, terahertz systems are susceptible to blockage. Here, we propose using Bessel beams to overcome issues caused by blockage due to their diffraction-free nature and self-healing properties in the near field. We compare the performance of information-bearing Bessel beams and Gaussian beams with and without an obstacle. We later discuss the use of reconfigurable intelligent surfaces to construct terahertz Bessel beams. Finally, we propose a metric to quantify the quality of imperfectly generated terahertz Bessel beams and explore their ability to self-heal. The results demonstrate that Bessel beams are an attractive option for near-field terahertz communications, especially when mitigating the effects of partial blockage.
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- PAR ID:
- 10467988
- Publisher / Repository:
- Nature Publishing Group
- Date Published:
- Journal Name:
- Communications Engineering
- Volume:
- 2
- Issue:
- 1
- ISSN:
- 2731-3395
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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