Introduction to Millimeter Wave Antennas

This chapter presents an overview of millimeter-wave antennas and important related issues. In particular, the unique properties of millimeter-wave propagation are addressed first. With a shorter wavelength, the millimeter-waves suffer from higher pathloss and worse diffraction in its propagation compared with microwaves. The wavelength of the order of millimeter determines the difference of applications of millimeter-wave wireless systems from the systems operating at lower or higher frequencies. Also, the design of antennas at this band has its own special considerations from the selection of types, feeding structures, materials, fabrication, and testing. In addition to the fast-developing applications, this chapter updates the latest development of applications of millimeter-wave technology in the 5G and future wireless communication networks as well.