A miniature low-current GaAs monolithic microwave integrated circuit (MMIC) downconverter with a novel image rejection filter was developed for commercial Ku-band broadcast satellite receivers. The low-noise RF amplifier, image rejection filter mixer, and intermediate-frequency amplifier were integrated on this MMIC. This MMIC used 0.3-μm-gate ion-implanted GaAs MESFETs. The individual circuit designs and performance are described. The current consumption of the MMIC downconverter was only 40 mA. The chip size of the MMIC downconverter with the image rejection filter was 1.7 mm × 2.05 mm.