Power amplifier behavioral modeling based on Laguerre Polar‐Volterra series with independent truncations

• Published in: International journal of RF and microwave computer-aided engineering Vol. 32; no. 5
• Main Authors: Nypwipwy, Vithor Bernardo, Cavalheiro, Ricardo Augusto da Silva, Dartora, César Augusto, Lima, Eduardo Gonçalves
• Format: Journal Article
• Language: English
• Published: Hoboken, USA John Wiley & Sons, Inc 01.05.2022; Hindawi Limited
• Subjects: Basis functions; behavioral modeling; independent truncation; Laguerre functions; Model accuracy; Modelling; power amplifier; Power amplifiers; Radio frequency; Volterra series
• ISSN: 1096-4290; 1099-047X
• DOI: 10.1002/mmce.23104

This article proposes an approach that modifies the Polar‐Volterra series expanded by a set of Laguerre Orthonormal Basis Functions and the Polar‐Volterra series using independent truncation techniques to significantly reduce the amount of parameters, where the resulting models reproduce the distortions of the nonlinearities of a radio frequency power amplifier (RF PA). An RF PA GaN HEMT class AB, stimulated by a wave centered at 900 MHz modulated by two 3GPP WCDMA envelope signals, each having a bandwidth of 3.84 MHz and shifted by 5 MHz, was used. A comparison of several models showed that the two proposed models, both containing a larger number of independent truncation factors, can provide a reduction over 50% in the number of generated coefficients, reaching a maximum of 84%. In another comparison with the other models, the modified Polar‐Volterra series expanded by a set of Laguerre functions significantly improved the modeling accuracy, quantified by improvements of normalized mean square error of up to 6.51 dB.