Design and analysis of a dc-43.5-GHz fully integrated distributed amplifier (DA) using a GaAs high electron-mobility transistor (HEMT) heterojunction bipolar transistor (HBT) cascode gain stage is presented in this paper. The proposed DA is fabricated in a stacked 2-mu m InGaP/GaAs HBT, 0.5-mu m Al-GaAs/GaAs enhancement-and depletion-mode HEMT monolithic microwave integrated circuit technology. A modified m-derived network and an HEMT-HBT cascode amplifier with inductive peaking technique are investigated to enhance the bandwidth of the DA. The bias networks of the DA are fully integrated in a single chip without off-chip bias-T or bias components. The measured average small-signal gain is 8.5 dB. The measured minimum noise figure is 4.2 dB. The measured maximum output 1-dB compression point (P(1 dB)) and the maximum output third-order intercept point are 8 and 18 dBm, respectively. Moreover, the DA is successfully evaluated with an eye diagram measurement, and demonstrates good transmission quality.
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