Title :
A 38–46 GHz MMIC Doherty Power Amplifier Using Post-Distortion Linearization
Author :
Tsai, Jeng-Han ; Huang, Tian-Wei
Author_Institution :
Dept. of Electr. Eng., Nat. Taiwan Univ., Taipei
fDate :
5/1/2007 12:00:00 AM
Abstract :
This letter describes the first demonstration of a fully integrated Doherty power amplifier (PA) monolithic microwave integrated circuit (MMIC) with post-distortion linearization at millimeter-wave (MMW) frequency band. The Doherty amplifier MMIC, using a 0.15-mum GaAs HEMT process, achieves a small signal gain of 7dB from 38 to 46GHz with a compact chip size of 2mm2. The saturation output power of the Doherty amplifier is 21.8dBm. The similar topology between the Doherty amplifier and post-distortion linearization makes it possible to improve efficiency and linearity simultaneously in MMW PA designs. After gate bias optimization of the main and peaking amplifier, the drain efficiency improved 6% at 6-dB output back-off and the inter-modulation distortion (IMD) of quasi Doherty amplifier can be improved 18dB at 42GHz compared with the balanced amplifier operation
Keywords :
III-V semiconductors; gallium arsenide; high electron mobility transistors; millimetre wave power amplifiers; 0.15 micron; 38 to 46 GHz; Doherty power amplifier; GaAs; MMIC; MMW; millimeter wave; monolithic microwave integrated circuit; post distortion linearization; Frequency; Gallium arsenide; HEMTs; MMICs; Microwave amplifiers; Microwave integrated circuits; Millimeter wave integrated circuits; Monolithic integrated circuits; Operational amplifiers; Power amplifiers; Doherty amplifier; millimeter-wave (MMW); monolithic microwave integrated circuit (MMIC); post-distortion;
Journal_Title :
Microwave and Wireless Components Letters, IEEE
DOI :
10.1109/LMWC.2007.895726
