In Sections 4, 5, and 6, the performances of planar printed monopole, wide-slot, and dipole antennas for wideband and UWB applications are illustrated. In Section 3, the characteristics of monopole antennas over metal plates are discussed. In Section 2 the features of some wideband microstrip antennas are presented. Particular emphasis is given to geometries, radiation mechanisms, broadbanding methods, materials, and prediction numerical tools adopted to the analysis and design of these important classes of antennas. To this end, in this paper a comprehensive review of the scientific literature of the last decade concerning these aspects is taken into account with the aim to provide researchers and designers with a valuable support tool to the antenna design. These antennas may in some cases meet the demanding requirements of the existing communication systems, while they can be the starting point from which to develop new radiating systems suitable for the future communication requirements. In general, 2D and 3D antenna technologies developed for wideband, multiband, and UWB applications can be divided into the following groups: microstrip antennas, monopole antennas over metal plates, printed monopole/dipole antennas, wide-slot antennas, metamaterial antennas, and dielectric resonator antennas (DRAs). This is particularly meaningful in wireless body area networks (WBANs) where high performances, as well as antenna flexibility under bending conditions, are important issues. In addition, antenna conformability may be a useful requirement to reduce the size and improve the look of mobile devices, while it results in an essential requirement for on-body type communication systems. Planar, printed (2D profile), and 3D antennas have been developed with the aim of meeting the integration requirements and transportability of handheld devices (mobile phones, laptops, tablets, etc.) as well as those of radio base stations and vehicles (cars, airplanes, ships, etc.). This is particularly relevant in UWB applications operating in the extended frequency bands listed in Table 1, where the communication standards adopted by the major countries in the world are reported. Many efforts are underway to identify new antenna geometries suitable to satisfy the challenging requirements of the modern wireless communication systems. In fact, the rapid growth of mobile systems toward the fifth-generation (5G systems) requires multiband, wideband, and UWB antennas suitable to cover mobile and wireless services and to reduce the system complexity, the overall device dimensions, and costs. The antenna design for high-speed multimedia connectivity represents a challenging activity for designers of fixed and mobile wireless communication systems. This information provides a guidance to the selection of the different antenna geometries in terms of bandwidth, gain, field polarization, time-domain response, dimensions, and materials useful for their realization and integration in modern communication systems. The performances of small, low-profile, and dielectric resonator antennas are illustrated paying particular attention to the application areas concerning portable devices (mobile phones, tablets, glasses, laptops, wearable computers, etc.) and radio base stations. Planar, printed, dielectric, and wearable antennas, achievable on laminate (rigid and flexible), and textile dielectric substrates are taken into account. A comprehensive review concerning the geometry, the manufacturing technologies, the materials, and the numerical techniques, adopted for the analysis and design of wideband and ultrawideband (UWB) antennas for wireless applications, is presented.
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