In this paper, a three-layer dielectric structure is presented as innovative unit-cell element for transmitarray (TA) antennas with enhanced bandwidth. It consists of central layer, varying size square hole, used to compensate the phase incident field and located between two other identical layers linearly tapered holes, acting matching circuits. The effectiveness demonstrated by numerical experimental results here presented. As first step, three different TAs increasing are designed...

In this paper, the design of a beam scanning, 3D-printed dielectric Transmitarray (TA) working in Ka-band is discussed. Thanks to use an innovative three-layer unit-cell that exploits tapered sections enhance bandwidth, 50 × elements transmitarray with improved scanning capabilities and wideband behavior has been designed experimentally validated. The measured radiation performances over coverage ±27 ∘ shown variation gain lower than 2.9 dB 1-dB bandwidth any case higher 23%. promising...

Evolutionary algorithms can be successfully exploited for carrying on an effective design of beam-scanning passive reflectarrays, even if the problem is highly non-linear and multimodal. In this article, Social Network Optimization (SNO) algorithm has been used assessing procedure a reflectarray (RA). For exploiting at most optimization capabilities SNO, entire environment deeply analyzed in all its parts. The performance SNO optimized RA have assessed through comparison with other well...

This paper explores the possibility of integrating a smart electromagnetic skin into street light or traffic pole to enhance coverage 5G base station operating in millimeter-waves frequency band with consequent improvement wireless network performance. Specifically, characteristics curved skin, which can be easily integrated cylindrical radome enclosing pole, have been analyzed and compared those planar solution. Additionally, provided by real urban scenario has considered. The obtained...

In this article, a dielectric-only reflectarray (RA) with wideband behavior is proposed as an alternative to conventional metallo-dielectric configurations. The introduced unit-cell (UC) consists of single dielectric layer perforated square hole located at the center, whose size used control phase reflection coefficient. For such element, accurate equivalent circuit model for predicting coefficient derived by combining two different concepts: effective medium theory characterize permittivity...

The feasibility of a wireless communication system to be use by scuba divers in case danger, adopting radiofrequency electromagnetic wave technology, is investigated. Some results on the characterizing feature propagation inside water are reported, together with principal constrains that environment introduced design entire and its antenna more specifically.

In this paper, preliminary results on the feasibility of a multibeam antenna based use transmitarray are presented. A reduced size configuration has been properly designed and optimized, with aim to minimize degradation radiation pattern introduced by variation in direction maximum radiation. Thereafter, numerical analysis obtained performed.

In this paper some results on the analysis of a recently introduced family optimization algorithms, named M <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">m</sub> C xmlns:xlink="http://www.w3.org/1999/xlink">n</sub> -BBO are presented. The algorithms have been generated starting from Biogeography Based Optimization (BBO) algorithm, introducing new features aimed to improve convergence and reliability methods. Here, is applied antenna problems:...

In this paper, some preliminary results on a 3D-printable dielectric Reflectarray antenna are presented. The unit-cell consists of single-layer element perforated with square hole, whose side is used to control the phase response. It has been adopted design 32×32 offset working in Ka-band. shown maximum gain 24.8 dB at 30 GHz and good radiation performances. Moreover, can be easily printed using Additive Manufacturing techniques.

Underwater Communication has a wide range of applications. In the case short-range communication system, use electromagnetic waves been recently proposed as an alternative to mostly used acoustic waves. The design antennas be for underwater is strongly influenced by properties water and therefore, after its but before experimental characterization, it necessary perform accurate numerical analysis behavior. As proof-of concept, here results obtained with full-wave designed system between...

In this work, preliminary results on the design of a dielectric transmitarray (TA) antenna are presented. The unit-cell consists in two circular cylinders located sides thin square slab, with size <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\boldsymbol{ 0.3}\lambda$</tex> at central frequency, realized same material cylinders. amplitude and phase transmission coefficient controlled varying diameter cylinders, while their height is kept...

In this paper, a new unit-cell is introduced with the aim of improving efficiency and bandwidth dielectric perforated transmitarray antennas. The behavior proposed compared that conventional one, consisting single layer central square hole. structure here proposed, two additional tapered layers have been added, acting as matching circuits. Two antennas 40×40 elements, each using one unit-cells, designed numerically characterized. results show significant performance improvements when used:...

A key element in next generation 5G communication systems is the adopted antenna configuration. Among several possible solutions, particularly interesting for this application are Multiple-Input Multiple-Output (MIMO) antennas, that allow to improve channel capability exploiting spatial properties of itself. In paper, after some general considerations on MIMO preliminary results an innovative configuration their realization presented.

In this paper, some numerical results on the scanning capabilities of a bifocal dielectric transmitarray (TA) are presented. The TA surface has been discretized with three-layer unit cells: central one presents varying size square hole, used to control phase transmission coefficient, while two identical, external layers characterized by truncated pyramid hole and they act as matching elements. computed antenna radiation patterns stay quite stable an angular range ±40°, keeping in each...

In this paper, we investigate the possibility of using cylindrical antennas for short-range underwater communication in freshwater. The performances three types are compared: dipole, monopole and folded dipole. freshwater wavelength is 9-10 times lower than free space at a specific frequency. This allows reduction antenna actual length therefore to work frequencies, where attenuation introduced by water lower, too. dimensions derived well-known analytical model. have been designed simulated...

In this paper, some numerical results on the possibil-ity to design a 3D-printable dielectric ReflectArray (RA) antenna with beam steering capabilities are presented. The adopted unit-cell consists of single-layer element perforated square hole, whose side is varied change phase reflection coefficient. Since behavior quite stable direction arrival incident field, it used 52 × reflectarray working in Ka-band. Its characterization proves that RA able provide less than 2 dB gain losses over...

Recently, the possibility of increasing performance 5G and beyond wireless networks with use "smart electromagnetic skin" able to provide coverage in blind zones for a base station, is becoming an object several studies. In this framework, curved configuration, which can be easily integrated into cylindrical radome enclosing street light or traffic pole, analyzed. The obtained numerical results prove that proposed solution guarantees even better than planar configuration occupying same...

An evolved antenna is an designed fully or substantially by automatic computer design program that uses evolutionary algorithm. In this article, we present our work in using algorithms to automated system. Based on the primal individual structure of genetic programming (GP) a tree form, new data-structure which can be represented as entire parameters has been explored. The first experiment done successfully for 5G mobile device microstrip patch (MPA) operates at 3.5 GHz with 50-160 MHz...