High-efficiency monolithic GaAs power MESFET amplifier operating with a single low voltage supply for 1.9-GHz digital mobile communication applications

A monolithic GaAs power amplifier IC using refractory WN/sub xW self-aligned gate power MESFETs has been developed for 1.9-GHz digital mobile communication systems, such as the Japanese personal handy phone system. The power amplifier operates with high efficiency and low distortion with a single low voltage supply of 2.7-3.0 V, by virtue of small drain knee voltage, high transconductance and sufficient breakdown voltage of the power MESFET. An output power of 23.7 dBm and a high power-added efficiency of 24.2% were attained at 3 V for 1.9-GHz /spl pi4-shifted QPSK (quadrature phase shift keying) modulated input when adjacent channel leakage power was -58 dBc at 600 kHz apart.<
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