Design and realization of driving amplifier MMIC circuit stages for KT IMT-2000 handset

In this paper, an IMT-2000 driving amplifier MMIC with variable gain amplifier (VGA) to linearly controlled output gain is designed, fabricated and analyzed. The driving amplifier (which is composed of three stages, the middle stage gain is 40 dB which is provided by cascaded junction of the three stages) is realized. We have designed a stable and reliable output stage driving amplifier for the KT IMT-2000 handset, and realized the following improved features: 3.5 times bandwidth, 15 dBm output power, 25/spl sim/27 dB output power gain, -15/spl sim/-20 dB VSWR, 3 dB gain flatness at the operating frequency.