Design of a 0.7GHz to 3GHz High-Linearity Drive Amplifier

This paper presents a drive amplifier, operating in the L and S bands, cascade structure and double parallel negative feedback and filtering matching networks are adopted. Compared to conventional feedback systems, the dual- parallel negative feedback enhances the gain flatness of the amplifier. Additionally, the filtering matching networks enable the characteristics of high linearity of the amplifier. A prototype of 0.7 GHz to 3 GHz power amplifier is implemented in 0.15 $\mu \mathrm{m}$ GaAs pHEMT process. It achieves an input and output return loss of less than -10 dB followed by flat power gain of 21 dB across the operating band, while sustaining an unconditional stability performance up to 10 GHz. The PA delivers an OIP3 of more than 36 dBm with peak PAE of 40%. The fully integrated circuit consumes an area of $2.4mm\times 1.4$ mm.