Analysis and Performance Evaluation of Power Amplifier Linearization Techniques

Abstract

Linearity performance has become a defining characteristic as it affects power efficiency, channel density, signal coverage, and adjacent channel power ratio. The non-linearity of Power Amplifier generates inter-modulation (IMD) components, also referred to as out-of-band emission or spectral re-growth, which interfere with adjacent channels. To attain high energy-efficiency, PAs should be operated at their output saturation regions but this operational mode could not provide high bandwidth-efficiency for a single-carrier high-order quadrature amplitude modulation (QAM) signals as well as multi-carrier orthogonal frequency division multiplexing (OFDM) signals. It is therefore difficult to compensate the nonlinearity of the power amplifier (PA) in the design of a wireless system. There are several techniques for power amplifier linearization. This paper is based on the mathematical analysis of these linearization techniques and their comparision.