1 watt broad Ka-band ultra small high power amplifier MMICs using 0.25-/spl mu/m GaAs PHEMTs

We report the design and performance of ultra compact high power amplifier MMICs for Ka-band applications. Using a production 4-inch 0.25-/spl mu/m GaAs PHEMT technology, in combination with appropriate compact circuit topologies, these power amplifiers achieved on wafer, a linear gain of more than 18 dB over the 26-36 GHz frequency range, with an output power at 1 dB gain compression of P/sub -1 dB/=29.5 dBm (900 mW) and a saturated output power above 1 watt (30.1 dBm), for a chip size of only 2.25 mm/sup 2/ (1.25/spl times/1.8 mm/sup 2/). To our knowledge, this is the highest output power and gain densities per chip area (i.e. 400-440 mW/mm/sup 2/ and 8 dB/mm/sup 2/) ever reported at Ka-band for any GaAs PHEMT MMIC power amplifier.