Phased array antennas for radar and telecommunications

The state of the art in phased array antenna technology, research and applications is explored. Phased arrays feature individual elements fed exciting radio frequency inputs that are phased in arithmetic progression. A plane wave is emitted by the array in a determinable direction. Array lobes are avoided by sending near-half wave impulses. Sidelobes are decreased in the far field by control of coupling effects, tolerances in the components during manufacture of the array, and phase shift. Phased array configurations thus far utilized include disk antennas, electronically scanning, rotating rectilinear arrays, and vertical scanning flat arrays. Research is being performed on fixed angle scanning directive antennas, toroidal or hemispherical covered antennas, and auto-adaptive grid antennas. Two main goals of radar research are to define antennas that are resistant to jamming and that can do all-azimuth tracking.