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Abstract In this paper, we propose radial line slot array antenna for 5G fixed beam solutions aimed at integrating multiple frequencies of high gain aperture into a single antenna with a common feed. Thus generated shared aperture will facilitate multi-functional antenna aperture for 5G new radio applications in FR-2 band. With increasing diversity in paradigms of communication systems, especially in mm-wave frequency bands, antenna arrays with specialized, multifunctional radiation capabilities are being pursued. This includes RLSAs for multi-band, multi-polarization and multi-beam radiation. This paper will introduce a low-profile, shared-aperture Radial Line Slot Array (SA-RLSA) antenna for these applications in the mm-wave frequency band. The available design methods for these antennas require complex feeding structures, which could be inconvenient for mass production. This work uses a simple capacitive hole-assisted coaxial feed and a conventional substrate containing the radiating slots on the upper plane. A shared aperture approach is adopted to generate beams at multiple frequencies with pencil and conical shapes and to obtain dual polarization. The measured responses from the fabricated samples for dual-band (28 GHz and 47 GHz), dual-beam (pencil beam at 28 GHz and conical beam at 47 GHz), and dual-pol (28 GHz and 47 GHz with X-pol and 38 GHz with Y-pol) showed a very good agreement with the simulated result. At operating frequencies,$$\sim$$20+ dBi gain is obtained, which can be enhanced by increasing the size of the slotted aperture.
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Absolute Security with Multiple-Slit Diffraction in Terahertz Communication Links
Many widely used antennas in terahertz (THz) directional communications (including horn antennas) are not fully compatible with the recently proposed absolute security approach due to the absence of strong frequency-dependent minima in the intrinsic antenna pattern. To this end, we propose to use a multiple-slit aperture to modify these non-suitable radiation patterns in a non-intrusive manner. Based on the principle of diffraction, the multi-slit aperture creates frequency varying minima critical for absolute security. We show that improved security performance, quantified by the size of the secure region in space (termed blind region), can be achieved by employing a wider diffraction aperture with a wider slit opening. We further characterize how the non-uniform wavefront, which is typical in practical transmission and results in varying amplitude and phase at different slit openings, affects the size of the blind region. This diffraction-based scheme is experimentally demonstrated with a horn antenna operating near 200 GHz. We demonstrate that, while the intrinsic horn antenna yields no blind region for angles within 16° from the intended user, the modified antenna configuration produces strong minima sufficient to create blind regions at angles as small as 4° and an expanding blind region with increasing transmission bandwidth, thus validating the security gain with this approach.
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- PAR ID:
- 10696495
- Publisher / Repository:
- Springer-Nature
- Date Published:
- Journal Name:
- Journal of Infrared, Millimeter, and Terahertz Waves
- Volume:
- 46
- Issue:
- 9
- ISSN:
- 1866-6892
- Page Range / eLocation ID:
- 58
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
-
Accepted Manuscript
- Journal Article:
- https://doi.org/10.1007/s10762-025-01073-5
