Mimix Broadband's 19.0-26.0 GHz GaAs MMIC transmitter has a +20.0 dBm output third order intercept and 15.0 dB image rejection across the band. This device is an image reject sub-harmonic anti-parallel diode mixer followed by a balanced two stage output amplifier and includes an integrated LO buffer amplifier. The image reject mixer reduces the need for unwanted sideband filtering before the power amplifier. The use of a sub-harmonic mixer makes the provision of the LO easier than for fundamental mixers at these frequencies. I and Q mixer inputs are provided and an external 90 degree hybrid is required to select the desired sideband. This MMIC uses Mimix Broadband's GaAs PHEMT device model technology, and is based upon electron beam lithography to ensure high repeatability and uniformity. The chip has surface passivation to protect and provide a rugged part with backside via holes and gold metallization to allow either a conductive epoxy or eutectic solder die attach process. This device is well suited for Millimeter-wave Point-to-Point Radio, LMDS, SATCOM and VSAT applications.