Envelope time-domain characterizations to assess in-band linearity performances of pre-matched MASMOS® power amplifier

Abstract

This paper reports on an innovative in-band linearity performances characterization dedicated to nonlinear RF power amplifiers, here, pre-matched MASMOS® power amplifier. It consists of a generic multi-tones test signal that emulates the statistical properties of the applicative signal and allows signal and intermodulation output component separation for in-band C/I (signal to intermodulation power ratio) calculation. Two types of tests are successively discussed. The first one are standards VSA-based measurement performed with a 16-QAM and 256-QAM modulated signal. Secondly, a specific multi-tones signal is presented and compared with the reference VSA measurement. It is shown that the proposed generic stimulus can be used to evaluate, in specific conditions, the in-band interferences that degrade the Error Vector Magnitude (EVM) in the case of a nonlinear link.