GPU-Based implementation of pruned artificial neural networks for digital predistortion linearization of wideband power amplifiers

This paper presents a feature selection technique based on l1 regularization to select the most relevant weights of artificial neural networks (ANNs) for digital predistortion (DPD) linearization of wideband radio-frequency (RF) power amplifiers (PAs). The proposed pruning method is applied to the f...

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Detalles Bibliográficos
Autores: Li, Wantao|||0000-0002-2634-6742, Criado Simón, Raúl, Thompson, William, Montoro López, Gabriel|||0000-0002-1328-4175, Chuang, Kevin, Gilabert Pinal, Pere Lluís|||0000-0001-6183-6977
Tipo de recurso: artículo
Fecha de publicación:2025
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:2117/445544
Acceso en línea:https://hdl.handle.net/2117/445544
https://dx.doi.org/10.1109/JMW.2025.3560420
Access Level:acceso abierto
Palabra clave:Radio frequency
Graphics processing units
Linearity
Artificial neural networks
Peak to average power ratio
Throughput
Predistortion
Real-time systems
Wideband
Power generation
Neural network
Power amplifier
Digital predistortion
GPU-based implementation
Predistortion linearization
Output power
Hidden layer
Processing unit
Graphics processing unit
Power efficiency
Relevant weight
Mean power output
Pruning strategy
Peak-to-average power ratio
Model performance
Behavioral model
Parallelization
Iterative learning control
Normalized mean square error
Throughput performance
Artificial neural network model
Orthogonal frequency division multiplexing
Reference signal
Digital signal processing
Parameter vector
Multiple blocks
Load-modulated balanced amplifier
Model-order reduction
Descripción
Sumario:This paper presents a feature selection technique based on l1 regularization to select the most relevant weights of artificial neural networks (ANNs) for digital predistortion (DPD) linearization of wideband radio-frequency (RF) power amplifiers (PAs). The proposed pruning method is applied to the first hidden layer of a feed-forward real-valued time-delay neural network, commonly used for DPD purposes. In addition, this paper presents the ANN-based DPD implementation using a graphic processing unit (GPU) with compute unified device architecture (CUDA) units. Thanks to the proposed pruning strategy, it is possible to reduce the ANN complexity significantly, thereby achieving a higher data throughput with the GPU-based implementation. The trade-off among RF performance metrics, number of model parameters and throughput of the GPU implementation is evaluated considering the linearization of a high-efficiency pseudo-Doherty load modulated balanced amplifier (LMBA). The linearized PA operating at an RF frequency of 2 GHz delivers a mean output power of 40 dBm with approximately 50% power efficiency when excited with 5G new radio (NR) signals with up to 200 MHz bandwidth and an 8 dB peak-to-average power ratio (PAPR). The real-time GPU implementation of the ANN-based DPD can meet the linearity specifications with a throughput circa 1 GSa/s.