An Upgraded Dual-Band Digital Predistorter Model for Power Amplifiers Linearization

Abstract

Digital predistortion (DPD) based on Volterra models is commonly employed to counteract nonlinear distortion of power amplifiers. However, when concurrent dual-band signals are transmitted, two-dimensional DPD models are required. In this work an upgrading of a standard dual-band model is proposed and justified using multinomial theorem. The linearization performance of the current proposal has been compared to the unextended model. 5G New Radio signals have been generated to compose a dual-band signal, which later was employed as input signal at Chalmers University of Technology's RF WebLab. Using coefficient selection techniques, the most relevant regressors are shown and the importance of the new extension is proven. Linearization results highlight the benefits of this proposal.

Predistortion-Based Linearization for 5G and Beyond Millimeter-Wave Transceiver Systems: A Comprehensive Survey

“…Neural Network-Based Model Waveform Processing at Transmission and Observation Path [67], [81], [89]- [103] [110]- [120], [122], [123] [67], [75], [82]- [88] DAC and ADC nonidealities [29], [130], [133]- [141] RF Sub-Components Effects [130]- [132], [142], [145] [130], [131] Amplitude-Compensated Phase Shifter [78], [79], [148]- [155], [157], [158] Phase-Compensated and Low-Noise Variable Gain Amplifier [44], [149], [159]- [169] SVM-Based Model better output performance. Since the invention of wireless communication, the linearity of transmitting signals hold paramount importance [73], [74].…”

“…Interestingly, the nonlinearity modeling is also evolved with every mobile generation, based on the necessary distortion (ACPR) levels assisted by the governing authorities [77]. From the linearization of standalone TX elements to the mMIMO TRX compounds [49] about maintaining the uniform phase setting of the desired beam through analog circuitry [44], [78], [79] or squeezing the IB nonlinear distortion via DPD assembly [80], [81] intimates the successful deployments of PD schemes from recent times.…”

“…In this regard, several algorithms from the family of greedy pursuits techniques have been proposed to reduce the cross-correlation complexity at high orders without losing the nonlinearity prediction for the leading, and lagging terms of IB carrier signal [98], [99]. A similar research group extended their discussion for the sparse MP (SMP) model of VoS, emphasizing the doubly orthogonal matching pursuit (DOMP), which is a modification of the Gram-Schmidt orthogonalization process [44], [81], [100]. The SMP formulation benefits signal with high sampling rates or wideband modulations.…”

Research on robust adaptive sliding film fault-tolerant control under nonlinear distortion of signal transmission in amorphous flat air-to-ground wireless ad-hoc network system

“…This paper uses the power series model as the nonlinear mathematical model of the power amplifier. In the literature (Dalbah et al , 2020; Wang et al , 2019c; Pérez-Hernández et al , 2021), the baseband equivalent input and output relationship are shown in equation (1): where i denotes the i-th wireless communication transmit link. To make a clarification here, the power amplifier because it is at the transmitting end of the subsystem, i can denote both the i-th subsystem and the transmitting link of the i - th subsystem.…”

“…This paper uses the power series model as the nonlinear mathematical model of the power amplifier. In the literature (Dalbah et al, 2020;Wang et al, 2019c;Pérez-Hern andez et al, 2021), the baseband equivalent input and output relationship are shown in equation ( 1):…”