Title :
An MMIC low-distortion variable-gain amplifier using active feedback
Author :
Nishikawa, Kiisa ; Tokumitsu, T.
Author_Institution :
NTT Wireless Syst. Labs., Kanagawa, Japan
Abstract :
A new low-distortion variable-gain amplifier (VGA) is proposed and analyzed. The gain of the VGA is controlled using the transconductance of a common-drain FET (CDF) in the negative feedback path. The analysis and prototype results indicate that the third-order intermodulation-distortion ratio is greatly improved at a high input power levels due to the CDF´s unilateral characteristic and a reduction in the VGA´s input impedance.<>
Keywords :
MMIC amplifiers; feedback amplifiers; field effect MMIC; gain control; intermodulation distortion; MMIC amplifier; active feedback; common-drain FET; intermodulation-distortion; low-distortion amplifier; negative feedback path; third-order IMD ratio; transconductance; variable-gain amplifier; Degradation; Equivalent circuits; FETs; Impedance; Laboratories; Linearity; MMICs; Negative feedback; Prototypes; Transconductance;
Conference_Titel :
Microwave Symposium Digest, 1995., IEEE MTT-S International
Conference_Location :
Orlando, FL, USA
Print_ISBN :
0-7803-2581-8
DOI :
10.1109/MWSYM.1995.406286
