Pages
- 1
- 2
- document
-
Ozzola, R. (author), Neto, A. (author), Imberg, Ulrik (author), Cavallo, D. (author)We present a dual-polarized connected array of slots with an artificial dielectric layer (ADL) radome for mobile communication applications operating in the sub-6 GHz and the upper 6 GHz bands of 5G. The radiating slots are combined with two interchangeable ADL radomes with different thicknesses, targeting the bands 6-8 and 2-8 GHz,...journal article 2024
- document
-
Coco Martin, C.M. (author), Hu, Weiya (author), Cavallo, D. (author)This work aims to provide guidelines on the design of wideband flat lenses based on artificial dielectric layers (ADLs). Planar lenses based on metasurfaces are typically narrowband, due to the phase wrapping over the period of 2\pi that is strongly frequency-dependent. On the contrary, true-time-delay (TTD) planar lenses, which do not resort...journal article 2024
- document
-
Hu, Weiya (author), Coco Martin, C.M. (author), Cavallo, D. (author)A semi-analytical method is presented for the design of gradient index (GRIN) flat lenses. Closed-form expressions are derived to define the refractive index distribution of the lens, for several cases: collimating lenses with on-axis feed, collimating lenses with off-axis feed, lenses converting spherical wavefronts with different...journal article 2024
- document
-
van Schelven, R.M. (author), Syed, Waqas (author), Carluccio, G. (author), Doris, Kostas (author), de Graauw, Anton (author), Neto, A. (author), Cavallo, D. (author)In this work, we investigate antenna architectures to implement dual-mode operation in phased array designs. Planar slot antenna elements are used in array configuration, in combination with artificial dielectrics layers (ADLs) located in the close proximity of the array, to achieve pattern shaping. The artificial dielectric superstrate...journal article 2023
- document
-
van Schelven, R.M. (author), Spirito, M. (author), Cavallo, D. (author)In this study, an efficient power combiner for mm-wave frequency transmitters is investigated. The combiner is based on a parallel plate waveguide (PPW) excited with multiple parallel feeds. The Doherty power combiner scheme is also integrated in the proposed concept, to increase the efficiency of the amplifiers when implementing amplitude...journal article 2023
- document
-
Hoogelander, M. (author), van Berkel, S.L. (author), Malotaux, E.S. (author), Alonso Del Pino, M. (author), Cavallo, D. (author), Spirito, M. (author), Llombart, Nuria (author)This article presents the development of a focal plane array (FPA) for terahertz imaging applications with a near diffraction-limited resolution achieved through a very tight sampling of the focal plane. The antenna array is integrated with direct detectors in a 22-nm CMOS technology and operates from 200 to 600 GHz. The tight sampling of the...journal article 2023
- document
-
Amendola, Giandomenico (author), Cavallo, D. (author), Chaloun, Tobias (author), Defrance, Nicolas (author), Goussetis, George (author), Margalef-Rovira, Marc (author), Martini, Enrica (author), Quevedo-Teruel, Oscar (author), Valenta, Vaclav (author)Low-Earth orbit (LEO) constellations are revolutionizing the world of satellite communication (Satcom), providing new opportunities to manufacturers and operators and enabling innovative and attractive services to users.journal article 2023
- document
-
van Schelven, R.M. (author), Cavallo, D. (author)We present a general analysis to describe nonsquare artificial dielectric layers (ADLs). Closed-form expressions for the equivalent layer impedance are given for generic plane-wave incidence, assuming that the ADLs have different geometrical parameters in the {x}-and {y}-directions. The analytical expressions account for the interaction...journal article 2022
- document
-
Pascual Laguna, A. (author), Cavallo, D. (author), Baselmans, J.J.A. (author), Llombart, Nuria (author)This communication proposes a broadband and efficient integrated focal plane array solution based on a near-field focused connected array of slots. The focused aperture provides: 1) broadband and highly efficient illumination of the quasi-optical system and 2) scanning capabilities within a focusing system. The connected array antenna in turn...journal article 2022
- document
-
Cavallo, D. (author)A novel approach for the practical realization of the feeding lines in connected array of slots is presented. The proposed feed concept is based on a parallel-plate waveguide (PPW) structure and allows simplifying the unit cell design. When compared to the typical integrated coaxial feed, the PPW-based feeding structure can reduce the cost...journal article 2022
- document
-
Ozzola, R. (author), Cavallo, D. (author), Neto, A. (author)We present a study on beam coupling in radiating structures that support multiple simultaneous beams. The formation of multiple beams is relevant in modern wireless communication applications when diverse data streams can be sent from a single transmitter to users located in different directions. General expressions are provided that relate...journal article 2022
- document
-
Van Katwijk, Alexander J. (author), Neto, A. (author), Toso, Giovanni (author), Cavallo, D. (author)We present an efficient method for the analysis of finite connected slot arrays in the presence of stratified media. The formulation is based on a spectral method of moments, where only one basis function is considered for each array element and one for each slot edge. An expression for the mutual impedance is derived in terms of a double...journal article 2022
- document
-
Ozzola, R. (author), Cavallo, D. (author), Freni, Angelo (author), Llombart, Nuria (author), Neto, A. (author)The number of independent links that can be hosted by an antenna platform for Line-of-Sight (LoS) communications is limited by its physical size and the interference between the beams associated with different users. For large-size platforms, the interference can be reduced by compromising the aperture efficiency, and this trade-off is the...journal article 2022
- document
-
van Berkel, S.L. (author), Malotaux, E.S. (author), De Martino, C. (author), Spirito, M. (author), Cavallo, D. (author), Neto, A. (author), Llombart, Nuria (author)A complete system modeling and characterization of a wideband differential terahertz (THz) direct detector, integrated in a commercial CMOS technology, is presented. The detector consists of a recently developed double leaky-slot lens antenna that operates from 200 to 600 GHz in combination with a differential Schottky barrier diode (SBD) direct...journal article 2021
- document
-
Tokan, F. (author), Cavallo, D. (author), Neto, A. (author)Three-dimensional body scanning systems are increasingly used in sensitive public areas such as airports. By providing a high resolution image of a person from all sides, it is possible to detect potential metallic, ceramic and explosive threats. For these systems, it is essential to design broadband antennas with a fan beam, highly directional...journal article 2020
- document
-
Yepes Julia, C. (author), Gandini, E. (author), Monni, S. (author), Neto, A. (author), Vliet, F. E. van (author), Cavallo, D. (author)In this letter, we present a design of a linear array of tilted dipoles to achieve radiation patterns with asymmetric angular filtering characteristics. To realize the asymmetric radiation, the dipole elements are spaced by a distance larger than half a wavelength, thus allowing for grating lobes to occur in the visible region. Moreover, the...journal article 2020
- document
-
van Schelven, R.M. (author), Cavallo, D. (author), Neto, A. (author)We present a systematic approach to describe planar slot antennas embedded in generic stratified media. An equivalent transmission line model for the slot is proposed, based on a spectral domain analysis. First, we introduce a method of moments solution to model semiinfinite or finite slots, fed by a delta-gap excitation. The solution entails...journal article 2019
- document
-
Yepes Julia, C. (author), Cavallo, D. (author), Gandini, E. (author), Monni, Stefania (author), Neto, A. (author), van Vliet, Frank E. (author)A five-layer frequency selective surface (FSS) composed of subwavelength elements with large harmonic rejection bandwidth is presented. The FSS design is based on an equivalent circuit model, where the interlayer interaction is only described with a single transmission line representing the fundamental Floquet wave. A prototype of the...journal article 2018
- document
-
Cavallo, D. (author)Closed-form expressions to describe artificial dielectric layers (ADLs) with finite conductivity are presented. The propagation of a generic plane wave within the artificial material is described by means of transmission line models, where each layer is represented as an equivalent shunt impedance. The given analytical formulas for the shunt...journal article 2018
- document
-
Cavallo, D. (author), Syed, W.H. (author), Neto, A. (author)In this work we report on the design, manufacturing and testing of a dual-polarized array of connected slots radiating in the presence of an artificial dielectric superstrate. The prototype array consists of 512 elements, i.e. 16×16 connected slots for each of the two polarizations. The antenna array is realized with a single multi...journal article 2018
Pages
- 1
- 2