Radar Antennas

Abstract

The radar antenna plays an important role in the radar system, and the requirement of radar antenna performances and functions is varied with different radar types. The radar antenna forms a highly directive beam in both transmit and receive modes, which achieve accurate angular targets and resolve closely located targets, and this important feature of the radar antennas can be quantitatively expressed in terms of the beamwidth, gain, and sidelobes. Besides, the functions of radar antennas can be classified into beam scanning (search or surveillance target) and target tracking. In the increasingly complex electromagnetic (EM) world, digital coding and programmable metamaterials and metasurfaces have been enabling commercial opportunities with a broad impact on radars and wireless communications. Because the subject of radar antennas is very extensive, in this chapter, only selected types and performances of radar antennas are discussed and then four different antennas (reflector antennas, phased‐array antennas, space‐fed arrays, and metamaterial antennas) are summarized.