GLORHIA- non-diffracting Geodesic Lenses fOR HIghly efficient directed-energy Applications
Abstract
We propose investigating, for the first time, the implementation of fully metallic geodesic lenses for near-field applications. In particular, we propose to explore the unique combination of geodesic lenses and ray-tracing methods to investigate on the performance achievable when operating in near field, targeting the generation of a non-diffracting beams radiating high power density up to the non-diffracting range. To achieve this challenge, we propose to study and implement an ad hoc ray-tracing code able to compute the near-intermediate electric field of arbitrary lens design (geodesic shapes included) with non-diffracting characteristics. They may be an opportunity to produce highly efficient, highly directive (with unconventional scanning abilities), and cost effective antenna solutions. Due to the relatively large electrical size of lenses (by construction constituted by many wavelengths), the study and design of geodesic lenses using commercial software is highly time-consuming and in many cases impractical. In terms of this, KTH in Stockholm together with Prof. Francisco Mesa with the University of Seville (Spain) have developed a ray tracing method to design lenses in an accurate and fast manner. We propose to explore the combination of geodesic lenses and ray-tracing methods to investigate geodesic non-diffracting beam launchers that can allow us to uniquely solve the aforementioned problem. To achieve this challenge, we must study and update an ad hoc ray-tracing code able to compute the near-intermediate electric field of arbitrary lens design (geodesic shapes included) with non-diffracting characteristics. New solutions involving a new physical approach are investigated. First, the code will be updated and tested through the design of a more conventional graded-index dielectric lens capable of synthesizing a non-diffracting near field. The possibility of generating Bessel beams and-or pseudo-Bessel beams will be assessed. Afterwards, we will use this code to demonstrate the possibility of producing a fully metallic, highly efficient (up to 80percent total) geodesic Bessel beam launcher. Using more feeding points of the lens, the proposed solution can also offer large scanning capabilities of a non-diffracting beam along one direction. The proposed design method is completely independent on the frequency. The band of operation will be, for example, 27-32 GHz (Ka-band) or 56-62 GHz (V-band). Higher frequencies are also possible with the geodesic type thanks to the absence of dielectrics, as desired to design very electrically large geodesic launchers and therefore to reach NDRs up to hundreds of wavelengths. Given the wideband and non-dispersive nature of this new approach, there is strong potential to extend the method to the generation of non-diffracting pulses (e.g., X waves), at millimeter waves and beyond, as well as to implement two scanning directions (over both horizontal and vertical planes) designing vertically stacked geodesic lenses.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Feb 06, 2025
- Source ID
- FA86552517010
Entities
People
- Davide Comite
Organizations
- Air Force Office of Scientific Research
- Sapienza University of Rome
- United States Air Force