Recent advances in monolithic millimeter-wave arrays

It is pointed out that advances in both HEMT technology and array technology have made it feasible to fabricate solid-state arrays at the lower millimeter-wave frequencies, such as Ka-band. An overview of the relevant developments is presented, and it is noted that the basis for optimism is fourfold: rapid advances in GaAs monolithic circuits; radiating elements at millimeter waves are becoming much better understood; the understanding of thermal control issues is now more comprehensive and advanced; and a good practical understanding of different array constructs has been gained.<>