9 research outputs found
Multihyperuniform Shared Aperture Antenna Arrays for Multiband Unidirectional Emission Applications
The multihyperuniform disordered distribution is an aperiodic distribution that was firstly identified on avian eye retina and is the reason behind their wideband and highly directive vision attributes. In particular, five different photoreceptor species are arranged in a disordered manner following a hyperuniform distribution which provides low side lobe levels and highly directive radiation patterns, while the overall photoreceptor distribution is hyperuniform as well, hence the term multihyperuniformity. Inspired by this, we are applying the concept in the field of shared-aperture antenna array design and to prove the concept, design a penta-band shared-aperture antenna array of circular patches operating in microwave frequencies. The proposed antenna array has low side levels over the whole frequency bandwidth and provides high peak realized gain values at the patches' resonant frequencies
A Computational Model for Generating Multihyperuniform Distributions for Realistic Antenna Array and Metasurface Designs
An Ultra-Wideband (35:1) Shared-Aperture Antenna Array with Multihyperuniform Disorder
This paper is aimed at studying the concept of multihyperuniformity and applying it to the design of shared-aperture antenna arrays for ultra-wideband, broadside unidirectional emission. In this study, we present our work on the design of multiple frequency helical antenna arrays within a shared-aperture configuration, incorporating multihyperuniform disorder. The array consists of seven different intercalated helical subarrays and is optimized to cover a 35 : 1 continuous bandwidth at 0.4 – 14 GHz. We provide comprehensive details regarding the fabrication process and present measurement results. Our work provides a new alternative to existing solutions of antenna array designs and has wider applicability in electromagnetics. The proposed methodology extends the limitations for the realization of multi-band antenna arrays, surpassing the previously reported designs that operated in a maximum of three frequency bands, by incorporating naturally optimized disordered distributions
Investigation of Hyperuniform Disorder in Antenna Array Applications
The most commonly employed antenna array distribution is the periodic array, which as the operating frequency increases suffers from strong undesired grating lobes. In order to overcome this limitation, aperiodic or random distributions combined with array optimization algorithms have been employed in the past. In many cases, the convergence to the optimal solution can be extremely time-consuming and computationally demanding, especially when considering a large number of elements. Here, a new array design strategy is presented to provide a robust and efficient solution for the design of wideband antenna arrays, without the need for extensive optimization techniques. Researchers have discovered a new state of matter that lies between a liquid and a crystal, the so-called disordered hyperuniformity. Applying the theory of hyperuniform disorder to the field of antenna arrays results in overcoming the periodic array limitations and leads to optimized wideband distributions characterized by directive emission, with low side lobes and for wide beam-steering angles. Furthermore, the main lobe is surrounded by a weak emission region and the theoretical tools for controlling its size while properly selecting the optimal combinations for the number of elements and amount of disorder/order in the distribution are provided. In addition, inspired by the naturally optimized photoreceptor distribution that is found on the retina of avian eyes, this study employs the hyperuniform distribution for each of the subarrays that form the multi-band shared-aperture antenna array. This leads to the design of an ultra-wideband multihyperuniform shared-aperture antenna array made of seven different intercalated arrays with broadside emission that suppresses the grating lobes in a continuous 35 : 1 bandwidth while avoiding any element overlaps and with increasing peak far-field realized gain. As a result, the available aperture area is employed in an electromagnetically efficient manner
Benchmarking Computational Electromagnetics with the Large Resonant Circular Array of Electrically Short and Thick Dipoles
The phenomenon of resonances in large circular arrays of electrically short and thick dipoles was studied intensively in the nineties by Harvard’s Antenna Group, led by R. W. P. King and T. T. Wu. Here, we propose these arrays as a benchmark for modern 3D Computational Electromagnetics (CEM) solvers. Our proposed benchmark is challenging because it exhibits resonances which, for judicious choices of the parameters, can be extremely narrow. We present exploratory simulations of our proposed benchmark using COMSOL Multiphysics and ANSYS HFSS, and give detailed comparisons with previously published results
Extraordinary Directive Emission and Scanning from an Array of Radiation Sources with Hyperuniform Disorder
The main challenge in the antenna or laser array design is to find the element distribution that best meets the optimal performance for broadband emission and large angle beam steering. In the past, the design strategy was restricted to arrays with periodic, aperiodic, and random distributions, which are characterized by several fundamental limitations related to the operating frequency, the power consumption that arises from interelement interference, and the computation time required during the random optimization process. Furthermore, the interelement spacing has a lower or upper bound due to the elements' physical dimensions and the former prohibits the use of the aforementioned element distributions for small operating wavelengths, whereas the latter induces high-order grating lobes. We prove that hyperuniform disorder is an array element distribution evolving through natural selection processes that warrants a disordered solution to the array design when this is treated as a packing problem. We theoretically and experimentally report that the array with hyperuniform disorder exhibits extraordinary directive emission and scanning features, while being scalable for extra-large arrays without any additional computational effort