Design and characterization of a microwave feed-forward amplifier with improved wide-band distortion cancellation

Author

Hau, Y. K Gary ; Postoyalko, Vasil ; Richardson, John R.

Author_Institution

Sch. of Electron. & Electr. Eng., Leeds Univ., UK

Volume

49

Issue

1

fYear

2001

Firstpage

200

Lastpage

203

Abstract

A new approach to the design of a wide-band feed-forward amplifier (FFAMP) is presented in this paper. Phase equalizers are employed in an FFAMP to match the nonlinear delay/phase characteristics of the main and error amplifiers, improving phase balances within the cancellation loops and providing improvement in signal cancellations over a wide bandwidth. The proposed 1.7-1.9-GHz FFAMP was fabricated and characterized. The conventional FFAMP obtains an average of 15-dB third-order intermodulation (IM3) distortion cancellation over the whole bandwidth. With the phase equalizers, the proposed FFAMP achieves a further 6-dB reduction on IM3 level.

Keywords

UHF amplifiers; equalisers; feedforward; intermodulation distortion; linearisation techniques; microwave amplifiers; wideband amplifiers; 1.7 to 1.9 GHz; IM3 cancellation; amplifier characterization; cancellation loops; error amplifier; intermodulation distortion cancellation; linear amplifiers; main amplifier; microwave feedforward amplifier; nonlinear delay/phase characteristics matching; phase balances; phase equalizer design; third-order IMD cancellation; wideband distortion cancellation; Bandwidth; Broadband amplifiers; Circuits; Delay; Equalizers; Feedforward systems; Frequency; Microwave amplifiers; Nonlinear distortion; Phase distortion;

fLanguage

English

Journal_Title

Microwave Theory and Techniques, IEEE Transactions on

Publisher

ieee

ISSN

0018-9480

Type

jour

DOI

10.1109/22.900009

Filename

900009