Title :
Compensation of amplifier nonlinear phase response to improve wideband distortion cancellation of feedforward amplifiers
Author :
Hau, Y.K.G. ; Postoyalko, V. ; Richardson, J.R.
Author_Institution :
Dept. of Electron. & Electr. Eng., Leeds Univ., UK
fDate :
3/13/1997 12:00:00 AM
Abstract :
Feedforward amplifiers with very good distortion cancellation over narrow bandwidth have been reported. However, if an amplifier in a cancellation loop has a nonlinear phase response, the 180° phase difference between halves of the loop required for perfect cancellation cannot in general be maintained over a wideband if only simple delay line is used. The use of a phase equaliser to improve wideband feedforward cancellation is proposed. Simulated and measured results show a significant improvement in cancellation over the frequency range 1.7-1.9 GHz
Keywords :
UHF power amplifiers; delay lines; electric distortion; equalisers; feedforward; wideband amplifiers; 1.7 to 1.9 GHz; UHF power amplifiers; amplifier nonlinear phase response; cancellation loop; delay line; feedforward amplifiers; phase difference; phase equaliser; wideband distortion cancellation;
Journal_Title :
Electronics Letters
DOI :
10.1049/el:19970338
