Digital linearization of wideband envelope tracking power amplifiers for mobile terminals

This article presents a low-complexity linearization method to compensate for multisource nonlinear distortion in wideband envelope tracking (ET) power amplifiers (PAs) for 5G new radio (NR) mobile terminals. The proposed linearization approach consists in an envelope leakage cancellation (ELC) syst...

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Detalles Bibliográficos
Autores: Li, Wantao|||0000-0002-2634-6742, Montoro López, Gabriel|||0000-0002-1328-4175, Gilabert Pinal, Pere Lluís|||0000-0001-6183-6977
Tipo de recurso: artículo
Fecha de publicación:2023
País:España
Institución:Universitat Politècnica de Catalunya (UPC)
Repositorio:UPCommons. Portal del coneixement obert de la UPC
Idioma:inglés
OAI Identifier:oai:upcommons.upc.edu:2117/406097
Acceso en línea:https://hdl.handle.net/2117/406097
https://dx.doi.org/10.1109/TMTT.2022.3196691
Access Level:acceso abierto
Palabra clave:Radio frequency
Bandwidth
Linearity
Modulation
Wideband
Nonlinear distortion
Behavioral sciences
Digital predistortion (DPD)
Envelope tracking (ET)
Power amplifier (PA)
Radio frequency (RF) leakage
Àrees temàtiques de la UPC::Enginyeria de la telecomunicació
Descripción
Sumario:This article presents a low-complexity linearization method to compensate for multisource nonlinear distortion in wideband envelope tracking (ET) power amplifiers (PAs) for 5G new radio (NR) mobile terminals. The proposed linearization approach consists in an envelope leakage cancellation (ELC) system operating in the dynamic supply path and a 2-D digital predistortion (2-D-DPD) linearizer acting on the baseband complex modulated signal. In a first step, an envelope generalized memory polynomial (EGMP) behavioral model is proposed to compensate for the unwanted radio frequency (RF) leakage that appears at the output of ET modulator (ETM). Then, a baseband 2-D-DPD linearizer based on a slow envelope-dependent generalized memory polynomial (SED-GMP) behavioral model is used to further enhance the linearization performance. The proposed method is validated on a system-on-chip (SoC) ET PA board for mobile applications. The reported experimental results show how the proposed digital linearization approach can mitigate the linearity and efficiency trade-off in ET PAs. Consequently, the out-of-band linearity requirement of - 36 dBc of adjacent channel power ratio (ACPR) is met for 5G-NR test signals with bandwidths ranging from 60 to 200 MHz at 2.55 GHz (band B41), with an overall ET PA power efficiency ranging from 10.1 % and up to 16.5 % , depending on the signal bandwidth.