Antennas for broadband and multiple-standard communications must provide excellent performance in a small area. While a spiral antenna can provide consistent radiation patterns, the size reduction is often a problem, since the antenna’s design is related to the physical wavelengths of the operating frequencies. Fortunately, a miniaturized arm-width-tapered Archimedean spiral antenna (ATARSA) has been designed that delivers outstanding performance in a size that is dramatically reduced compared to conventional spiral antennas.
Antennas for ultrawideband (UWB) must exhibit wide operating bandwidth, but also small size for use in a variety of electronic devices. A monopole planar sleeve antenna may meet those requirements with a broad frequency range extending almost to 12 GHz. It consists of symmetrical strips and a ground plane on the same side, using a coplanar-waveguide (CPW) structure on low-cost FR-4 dielectric substrate material with relative dielectric constant of 2.95 and thickness of 1.6 mm. This antenna is suitable for worldwide interoperability for microwave access (WiMAX) applications.