An S-Band Image Rejection Receiver Front-End Incorporating GaAs MMICs

An S-band image rejection receiver front-end has been designed, using GaAs MMICs to provide all the necessary functions up to, and including, the mixers. The receiver system incorporates the following GaAs MMICs: lownoise amplifier, in-phase signal splitter, quadrature local oscillator splitter, passive routing chip and dual-channel mixer. The mixer chip is novel in that a single-gate FET is used in conjunction with a passive 3 dB RF/LO-combiner. The design and performance of these circuits are discussed in the paper, together with measured results for complete receiver front-ends using these circuits.