Analog predistortion power amplifiers using IMD sweet spots for WCDMA applications

An analog predistortion power amplifier (PA) using intermodulation distortion (IMD) sweet spots for linearity improvement in wide-band code division multiple access (WCDMA) applications is represented. A third-order predistorter is used to cancel the IM3 components when the IM5 components are significantly reduced by the IMD5 sweet spots of the PA. For experimental validation, a 30-W PEP LDMOSFET PA is implemented and tested for two-tone and 4-carrier WCDMA signals at 2.14 GHz. The measured results show that the notable linearity improvement is obtained over a whole output power range. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2838–2841, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22859

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