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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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This content will become publicly available on June 1, 2027
Secrecy Capacity of Airy Beams
Communication in the terahertz (THz) frequency band is a key focus for the next generation of wireless systems, in part because of the possibility for enhanced security in combination with ultra-high data rates. To enable communication links in the presence of blockage of a directional line-of-sight beam, self-accelerating THz beams have recently been proposed. For such beams, the main lobe radiated from an aperture follows some engineered curved trajectory in the electromagnetic near field. Self-accelerating beams enable advantages unlike traditional beams by curving around potential eavesdroppers located in the vicinity of the radiating aperture. Here, we theoretically and experimentally analyze the security implications of such beams by evaluating their secrecy capacity. We also explore the implications of blockage and self-healing on this security metric.
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- PAR ID:
- 10696500
- Publisher / Repository:
- IEEE
- Date Published:
- Journal Name:
- IEEE Transactions on Terahertz Science and Technology
- Volume:
- 16
- Issue:
- 6
- ISSN:
- 2156-342X
- Page Range / eLocation ID:
- 640 to 646
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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