A new linear amplifier using low-frequency second-order intermodulation component feedforwarding

Author

Yang, Youngoo ; Kim, Bumman

Author_Institution

Dept. of Electron. & Electr. Eng., Pohang Univ. of Sci. & Technol., South Korea

Volume

9

Issue

10

fYear

1999

fDate

10/1/1999 12:00:00 AM

Firstpage

419

Lastpage

421

Abstract

A new linearization method by feedforwarding low-frequency second intermodulation component (f₂-f₁) is proposed. Drain voltage modulation by forwarding second intermodulation voltage improves linearity significantly. This new technique, which adopts a simple circuit configuration, has advantages in the stability and bandwidth due to the feedforwarding nature and shows a very good performance in comparison with other harmonic tuning circuits. Analytical derivation of low-frequency feeding voltage gain (β) to obtain perfect cancellation of IMD₃ is presented. For verification of the proposed circuit topology, a two-tone test and a CDMA signal test at carrier frequency 2.15 GHz are performed and show about 18- and 10-dB improvement of IMD₃ and adjacent channel power ratio (ACPR), respectively

Keywords

circuit stability; circuit tuning; feedforward; intermodulation; microwave amplifiers; microwave circuits; 2.15 GHz; CDMA signal test; IMD₃; adjacent channel power ratio; bandwidth; carrier frequency; circuit topology; drain voltage modulation; harmonic tuning circuits; intermodulation component feedforwarding; linear amplifier; linearization method; low-frequency second-order intermodulation; perfect cancellation; stability; two-tone test; Bandwidth; Circuit analysis; Circuit optimization; Circuit stability; Circuit testing; Circuit topology; Frequency; Linearity; Multiaccess communication; Voltage;

fLanguage

English

Journal_Title

Microwave and Guided Wave Letters, IEEE

Publisher

ieee

ISSN

1051-8207

Type

jour

DOI

10.1109/75.798035

Filename

798035