ôJournal of Radio Electronics. eISSN 1684-1719. 2026. ¹8
Full text in Russian (pdf)
DOI: https://doi.org/10.30898/1684-1719.2026.8.13
POLAR POLYNOMIAL MODEL OF A DIGITAL PREDISTORTER
FOR COMPENSATION OF NONLINEAR DISTORTIONS
OF A MICROWAVE POWER AMPLIFIER
WITH AN UNMATCHED LOAD
L.I. Averina1, I.V. Zavgorodniy1, V.D. Shutov2
1Voronezh State University,
394018, Russia, Voronezh, Universitetskaya Sq., 12JSC «Concern «Sozvezdie»,
394018, Russia, Voronezh, Plekhanovskaya St., 14
The paper was received July 17, 2026.
Abstract. The paper presents a polar polynomial model of a digital corrector for compensating for nonlinear distortions of a microwave power amplifier with an unmatched load, which takes into account the separate influence of the magnitude and phase of the reflection coefficient on the nonlinear dynamics of the amplifier. The key advantage of the proposed model is the use of only input signal samples and the value of the complex reflection coefficient, which significantly reduces the computational and hardware complexity of implementing digital signal predistortion. The results of simulation modeling and comparative analysis confirm the high efficiency of linearization of the transmission path in a wide range of load changes using the developed model. Thus, the proposed approach allows us to recommend the developed polar polynomial model for practical application in modern wireless communication systems for the purpose of efficient linearization of output paths under conditions of real operational uncertainty of load impedance.
Key words: digital corrector, nonlinear power amplifier, learning architectures, mismatched load, reflection coefficient.
Financing: The study was supported by a grant from the Russian Science Foundation ¹ 24-19-00891, https://rscf.ru/project/24-19-00891/.
Corresponding author: Zavgorodniy Ilya Vyacheslavovich, zavgorodny@phys.vsu.ru
References
1. Nazarov L.E., Zudilin A.S. The influence of transmitter nonlinearities on multifrequency signals with orthogonal frequency division multiplexing // Journal of Radio Electronics. – 2010. – ¹. 12. – P. 5-5.
2. Averina L.I., Bobreshov A.M., Shutov V.D. Increasing the linearity of the transmission path using digital pre-distortion // Nonlinear world. – 2013. – Ò. 11. – ¹. 10. – P. 720-727.
3. Ghoniem A.A. et al. An error vector magnitude performance modeling and analysis methodology for 5G mm-Wave Transmitters // IEEE Microwave and Wireless Technology Letters. – 2023. – Ò. 33. – ¹. 6. – P. 771-774.
4. Romier M. et al. Load-pull effect on radiation characteristics of active antennas // IEEE Antennas and Wireless Propagation Letters. – 2008. – Ò. 7. – P. 550-552.
5. El Nashef G.Z. et al. EM/circuit mixed simulation technique for an active antenna // IEEE Antennas and Wireless Propagation Letters. – 2011. – Ò. 10. – P. 354-357.
6. El Nashef G.Z. et al. Second order extension of power amplifiers behavioral models for accuracy improvements // The 40th European Microwave Conference. – IEEE, 2010. – P. 1030-1033.
7. Fager C. et al. Prediction of smart antenna transmitter characteristics using a new behavioral modeling approach // 2014 IEEE MTT-S International Microwave Symposium (IMS2014). – IEEE, 2014. – P. 1-4.
8. Zargar H., Banai A., Pedro J.C. A new double input-double output complex envelope amplifier behavioral model taking into account source and load mismatch effects // IEEE Transactions on Microwave Theory and Techniques. – 2015. – Ò. 63. – ¹. 2. – P. 766-774.
9. Cai J., Gonçalves R., Pedro J.C. A new complex envelope behavioral model for load mismatched power amplifiers // International Journal of RF and Microwave Computer‐Aided Engineering. – 2017. – Ò. 27. – ¹. 6. – P. e21097.
10. Liu X. et al. Load-mismatch tracking digital predistortion technique for mobile-terminal power amplifiers // IEEE Transactions on Microwave Theory and Techniques. – 2023. – Ò. 71. – ¹. 1. – P. 158-172.
11. Jaraut P. et al. Behavior modeling and digital predistortion of mismatched wireless transmitters using convolutional neural networks // IEEE Transactions on Circuits and Systems II: Express Briefs. – 2023. – Ò. 70. – ¹. 1. – P. 336-340.
12. Eun C., Powers E.J. A new Volterra predistorter based on the indirect learning architecture // IEEE transactions on signal processing. – 1997. – Ò. 45. – ¹. 1. – P. 223-227.
13. Zhou D., DeBrunner V.E. Novel adaptive nonlinear predistorters based on the direct learning algorithm // IEEE transactions on signal processing. – 2007. – Ò. 55. – ¹. 1. – P. 120-133.
14. Chani-Cahuana J. et al. Iterative learning control for RF power amplifier linearization // IEEE Transactions on Microwave Theory and Techniques. – 2016. – Ò. 64. – ¹. 9. – P. 2778-2789.
15. Averina L.I., Guterman N.E. Comparative analysis of digital corrector training architectures in the problem of broadband power amplifier linearization // Ðàäèîòåõíèêà. – 2025. – ¹. 9. – P. 45-53.
16. Jaraut P. et al. Linearization of load mismatched power amplifiers using reflection-aware augmented polynomial model // IEEE Transactions on Circuits and Systems II: Express Briefs. – 2024. – Ò. 71. – ¹. 8. – P. 4025-4029.
For citation:
Averina L.I., Zavgorodniy I.V., Shutov V.D. Digital nonlinear distortion corrector for a microwave power amplifier with a mismatched load based on a polar polynomial model. // Journal of Radio Electronics. – 202X. – ¹. 8. https://doi.org/10.30898/1684-1719.2026.8.13 (In Russian)