1,176 research outputs found
Performance of hemielliptic dielectric lens antennas with optimal edge illumination
The role of edge illumination in the performance of compact-size dielectric
lens antennas (DLAs) is studied in accurate manner using a highly efficient
algorithm based on the combination of the Muller boundary integral equations
and the method of analytical regularization. The analysis accounts for the
finite size of the lens and directive nature of the primary feed placed close
to the center of the lens base. The problem is solved in a two-dimensional
formulation for both E- and H-polarizations. It is found that away from
internal resonances that spoil the radiation characteristics of DLAs made of
dense materials, the edge illumination has primary importance. The proper
choice of this parameter helps maximize DLA directivity, and its optimal value
depends on the lens material and feed polarization. Index Terms: Beam
collimation, dielectric lens antenna, directivity improvement, edge
illumination, edge taper, hemielliptic lens.Comment: 5 pages, 9 figure
Dielectric lens antennas
Dielectric lens antennas are attracting a renewed interest for millimeter- and submillimeter-wave applications where they become compact, especially for configurations with integrated feeds usually referred as integrated lens antennas. Lenses are very flexible and simple to design and fabricate, being a reliable alternative at these frequencies to reflector antennas. Lens target output can range from a simple collimated beam (increasing the feed directivity) to more complex multi-objective specifications. This chapter presents a review of different types of dielectric lens antennas and lens design methods. Representative lens antenna design examples are described in detail, with emphasis on homogeneous integrated lenses. A review of the different lens analysis methods is performed, followed by the discussion of relevant lens antenna implementation issues like feeding options, dielectric material characteristics, fabrication methods, and a few dedicated measurement techniques. The chapter ends with a detailed presentation of some recent application examples involving dielectric lens antennas
Perforated Dielectric Lens Antenna Design
In this paper, a dielectric lens in a three dimensional structure with a matching layer on a planar antenna platform was added to work on a high gain antenna. It has been shown that the antenna with the same parameters can be designed by reducing the cost of production by using the perforated dielectric lens method which can be used equivalent to the dielectric lens used. Due to the high production difficulties and high cost of lens antenna structures, alternative methods have been studied and successful results have been obtained by using a method with scientific innovation value.This work was supported by Research Fund of the Yildiz Technical University. Project Number:FBA-2017-3070
Terahertz Artificial Dielectric Lens
We have designed, fabricated, and experimentally characterized a lens for the THz regime based on artificial dielectrics. These are man-made media that mimic properties of naturally occurring dielectric media, or even manifest properties that cannot generally occur in nature. For example, the well-known dielectric property, the refractive index, which usually has a value greater than unity, can have a value less than unity in an artificial dielectric. For our lens, the artificial-dielectric medium is made up of a parallel stack of 100âÎŒm thick metal plates that form an array of parallel-plate waveguides. The convergent lens has a plano-concave geometry, in contrast to conventional dielectric lenses. Our results demonstrate that this lens is capable of focusing a 2âcm diameter beam to a spot size of 4âmm, at the design frequency of 0.17âTHz. The results further demonstrate that the overall power transmission of the lens can be better than certain conventional dielectric lenses commonly used in the THz regime. Intriguingly, we also observe that under certain conditions, the lens boundary demarcated by the discontinuous plate edges actually resembles a smooth continuous surface. These results highlight the importance of this artificial-dielectric technology for the development of future THz-wave devices
Impedance-matched microwave lens
A microwave lens with highly reduced reflectance, as compared to conventional
dielectric lenses, is proposed. The lens is based on two-dimensional or
three-dimensional transmission-line networks that can be designed to have an
effective refractive index larger than one, while having almost perfect
impedance matching with free space. The design principles are presented and an
example lens is studied using commercial simulation software.Comment: 11 pages, 8 figure
A low profile radiating element with nearly hemispheric coverage for satellite communications on-the-move hybrid array antenna
A novel design solution of a dual-linearly polarised Ku-band low-profile radiating element for low elevation angle coverage (down to 10° above horizon) is presented. Such an element is suitable for full-duplex Satellite Communications On-The-Move (SCOTM) hybrid scanned phased array antenna applications. Standard designed radiating elements for array applications with low profile physical structure suffer poor low elevation angle coverage as the element pattern reduces by sine of the elevation angle. The element design demonstrated in this paper features unique louvered array element geometry incorporating a spatial âray bendingâ lens facilitates the shaping of the element pattern to increase gain at low elevation angles. Preliminary modelling results using ray tracing analysis shows that the desired low angle coverage can be achieved. Currently in progress full 3D electromagnetic simulations which include the interaction between the basic radiator and the spatial lens indicates that using an ideal tilted element with novel louvered reflector in addition with proposed lens, low angular coverage can potentially be realised in a low profile structure
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