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In this paper, we present a fully automated procedure for the direct design of a novel class of single-feed flat antennas with patterning of a conductive surface. We introduce a convenient surface discretization, based on hexagonal cells, and define an appropriate objective function, including both gain and input matching requirements. The reference geometry is constituted by a very thin, single feed-point square panel. It features a backing metal plate (“ground”) and a top conductive layer, which is automatically patterned to achieve the desired radiation and input matching properties. The process employs an evolutionary algorithm combined with a boundary element electromagnetic solver. By applying this method, we designed an antenna tailored to the 2.4 GHz ISM frequency band, with a size of $$24\,\hbox {cm} \times 24\,\hbox {cm}$$24cm×24cm, i.e., $$2 \times 2$$2×2 wavelengths and an height of 4 mm, or 0.03 wavelengths. Measured data confirmed the expected high gain (13 dBi), with a remarkable aperture efficiency (higher than 50%, including losses), thus validating the proposed approach.

We present a novel algorithm for the synthesis of planar (2-D) arrays subject to arbitrary pattern masks and excitation constraints (e.g., dynamic range). The algorithm is simple and deterministic, and considers the radiating element pattern. The procedure starts with a conventional constrained fixed-grid synthesis on a regular lattice, yielding a goal radiated field. Next, element locations are selected sequentially by maximizing projection on field difference to goal, while excitation amplitudes are computed using fixed-grid constrained synthesis for irregular lattices. The final result is the sparse layout and constrained excitation coefficients. The proposed method is validated against literature results; application examples are given for circular flat-top, isoflux and triangular flat-top shaped beam patterns, with constraints on excitation coefficients dynamic range, both for isotropic and patch-type element patterns.

Some numerical results about the use of a Reduced Order Model to map currents to their radiated field in the presence of a scatterer are shown for antenna design and placement.

The project STRUCTURES, funded by the European Union, started in July 2012 to study problems related to the emerging threats of electromagnetic attacks to critical infrastructures. Partners of the team have worked to list possible threats, identify the main characteristics of the critical infrastructures our way of living depends on, test current protection strategies with different simulation and measurement techniques, and condensate the results in guidelines accessible to an audience wider than the one of people working in the field. Here, we summarize the challenges, the solutions, and the results of almost three years of work.

This paper proposes an innovative functional testing methodology suitable for RF end-to-end antenna testing. Any measurement point requires mechanical movement and signal integration time to produce a sample; thus, the most radical way to reduce testing time is to reduce the number of required measured samples to a minimum. The presented approach exploits existing measurement capabilities, and allows a radical under-sampling via insertion of a-priori information by way of suitable use of advanced numerical modeling tools. The methodology can be used also with non-canonical grids, and when only a limited number of measured points is available. Experimental results are provided to show the potentials of the method.

An overview of the European project STRUCTURES and its main challenges is given. Current and foreseen Intentional Electromagnetic Interference (IEMI) threats are classified according to their availability, their technical characteristics (such as bandwidth) and their portability. Critical infrastructures are identified and their most characteristic aspects are highlighted, from an electromagnetic point of view. These concepts are used to establish a set of reference threats to be investigated and possible techniques to handle simulations and measurements in this complex environment are explored, emphasizing the use of the topological approach. © 2012 IEEE.

This paper presents a comprehensive application of the Field-to-TL approach implemented through a computer framework designed to facilitate data exchange among different computational tools. The framework is used also to compare results from different codes, specifically MDD (Multilevel Domain Differentiate) and CRIPTE, thus providing a validation test case for both of them. Furthermore, the comparison with measurements gives an idea of the degree of accuracy obtained with such an operating approach.