|Abstract: Today, the wireless communications systems have become an integral part of daily life and continue to evolve in providing better quality and user experience. One of the recent emerging wireless technologies is millimeter wave (mm-wave) technology. It is important to note that mm-wave technology has been known for many decades, but has mainly been deployed for military applications. Over the past 5–6 years, advances in process technologies and low-cost integration solutions have made mm-wave a technology to watch and begun to attract a great deal of interest from academia, industry, and standardization bodies. Millimeter wave technology offers various advantages over current or existing communications systems. One major reason for the recent interest in mm-wave technology is the huge unlicensed bandwidth, around 7 GHz of continuous bandwidth is available in many countries worldwide. This massive spectral space enables densely situated, noninterfering wireless networks to be used in the most bandwidth-starving applications of the future, in all kinds of short-range (<1 km) wireless communication. This huge bandwidth represents great potential in terms of capacity and flexibility, making mm-wave technology particularly attractive for gigabit wireless applications. Generally, specified requirements for antennas used in mm-wave systems concern gain, radiation efficiency, operating bandwidth, technological reliability, cost, and compatibility with other RF modules. Significant efforts have been made during the past few years for designing and implementing efficient miniaturized antennas for mobiles or radio communications equipments. With the rapid development of advanced millimeter wave systems and applications, highly efficient antennas and RF circuits are required.The tutorial is dedicated to millimeter wave antennas and describes the main features and specificities of millimeter wave frequency range such as: technological and realization difficulties, antenna measurements, need to characterize the dielectric materials and consequences on the antenna performance, etc. Other types of mm-wave antennas and arrays will be presented than the printed antennas, 3D antenna technologies, including lenses, reflectors, leaky-waves, etc. Finally, major civil, military, automotive and medical applications of mm-wave antennas will be presented.
Abstract: Reconfigurable antennas are becoming more and more popular, a direct result of the important developments in the Telecom industry in general and the Wireless Communications domain in special. The apparition of multiservice radios and, at a higher degree, cognitive radios has considerably changed the way engineers deal with antennas. Previously, most of system engineers excluded the antenna from the evaluation of system performances; a best example is the evaluation of the system noise figure. Now, the antenna is becoming an important part of the system as it contributes to the signal processing by introducing both frequency and spatial filtering and also diversity. Some specialists talk today about Signal Processing Antennas.
In the present tutorial, the speaker will talk about the different approaches to design reconfigurable antennas and will use his experience in the field to give guidelines to decide which one to use for a specific application. For each approach, antenna examples will be given and the speaker will highlight the contribution of the antenna to the system performances.