Millimeter wave antennas

Millimeter wave antennas are primarily parabolic reflectors, Cassegrain systems, and lenses. Comparative merits and the few design features peculiar to millimeter waves are discussed. Some of these antennas have larger gain and much larger gain per unit cost than any other microwave antennas. A few experimental arrays and ferrite scanners have been built. Brief mention is made of absorbers and radomes at millimeter waves.