Development of a monolithic FET Ka-band single side band upconverter and image reject downconverter

Abstract

A GaAs monolithic, single-sideband (SSB), Ka-band FET upconverter is being developed for use in a miniature coherent radar transceiver module, along with a monolithic image reject downconverter. The SSB upconverter IC comprises balanced FET converters, Lange couplers, and an IF quadrature splitter. The balanced FET converters provide 7 dB of conversion loss and 28 dB of LO rejection. The SSB IC, currently in fabrication, is expected to provide 8 dB of conversion loss, 5 dBm of output power, and 28 dB of LO and 20 dB of lower sideband rejection. The image reject downconverter IC comprises a balanced pair of FET converters. Lange couplers, a Wilkinson divider, and a lumped element branchline coupler. The single FET converters produced 1 dB of conversion gain with a 5.5-dB noise figure, DSB. The image reject downconverter, currently in fabrication, is expected to provide 0 dB of conversion gain and 20 dB of image rejection with a noise figure of 9 dB, SSB.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>