Title :
Improving amplifier stability through resistive loading below the operating frequency
Author :
Kim, Sun-Wook ; Chang, Ik-soo ; Kang, Won-tae ; Kyung, In-Pyo
Author_Institution :
Dept. of Electron. Eng., Sogang Univ., Seoul, South Korea
fDate :
3/1/1999 12:00:00 AM
Abstract :
A new design method for a stable RF amplifier using a broadband-matched 3-dB coupled line is proposed in this paper. The proposed broad-band matching circuit consists of lossless matching circuits at operating frequency band and resistive matching circuits at frequencies below the operating band. This design method improves the stability of the amplifier and is suitable for the design of a power amplifier and multistage amplifier. When applying this proposed method to a design of a two-stage power amplifier for personal communication systems, measured results show 18.0dB gain and 9 W (39.5 dBm) output power
Keywords :
UHF power amplifiers; circuit stability; impedance matching; mobile radio; radiofrequency amplifiers; 0 to 1840 MHz; 18 dB; 9 W; amplifier stability; broadband matching circuit; design method; lossless matching circuits; multistage amplifier; operating frequency; personal communication systems; power amplifier; resistive loading; resistive matching circuits; stable RF amplifier; Broadband amplifiers; Circuit stability; Coupling circuits; Design methodology; Frequency; Gain measurement; Power amplifiers; Power generation; Power measurement; Radiofrequency amplifiers;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
