Bias Switching Amplifier Design and Linearization

This paper presents the design and linearization of high efficiency dual mode amplifier. A dual mode transmitter requires an amplifier which generates different output level for different applications. For WiBro, the output is 1 W at 2.3 GHz, and for wireless LAN, the output is less than 100 mW at 2.4 GHz, A bias switching amplifier is designed to get the higher efficiency at both applications With bias switching the amplifier shows the efficiency improvement of up to 25% point. This paper also shows the possibility of linearity improvement for the dual mode amplifier by using predistortion technique.