Behavioral Modeling of Chireix Outphasing Power Amplifier

Overview

During my time as a Visiting Scholar (2014–2016) and Ph.D. research at the RF Nonlinear Research Laboratory, Department of Electrical and Computer Engineering, The Ohio State University, I conducted extensive measurement campaigns and behavioral modeling of a Chireix outphasing power amplifier system.

Key Contributions

• Performed large-signal dynamic measurements of a Chireix PA using a nonlinear vector network analyzer (NVNA) to capture AM-AM, AM-PM distortion curves and dynamic efficiency behavior under modulated signal excitation.
• Developed NARMA-based behavioral models to accurately predict the nonlinear memory effects inherent to outphasing PA architectures, where signal recombination introduces load-dependent distortions.
• Validated models against LTE-Advanced waveforms, demonstrating improved prediction accuracy for efficiency and linearity metrics compared to conventional memoryless polynomial approaches.

Tools & Technologies

NVNA (Keysight PNA-X), MATLAB, automated RF testbed, signal generators, spectrum analyzers, Keysight ADS.

Impact

This work formed the core of my Ph.D. dissertation: “Measurement and Behavioral Modeling of Dynamic Efficiencies and Linearization of an LTE-A Chireix PA” (IPN-CITEDI, 2017), and was supported by an NSF Scholarship (2015–2016).