Amplificadores de potencia de alta eficiencia

The fast growth in modern wireless communication systems has set in motion a never-ending quest for greater capacity and higher data rates in radio access networks. These demands must be met within the existing radio base stations where cooling capacity and size are limited. At the same time, operators want to cut their expenses, of which energy consumption is a significant factor. Linear radio frequency (RF) power amplifiers (PA) play a major role in terms of energy consumption and heat dissipation. More efficient base station power amplifiers are thus a crucial factor in the context of mobile system evolution. In this conference, basic concepts for high efficiency power amplifier design will be reviewed, followed by the best known transmitter architectures and their application. Finally, a brief introduction in different linearization techniques will be given.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Consideraciones sobre el amplificador distribuido como amplificador de potencia

In this contribution, a short review of independent research activities on distributed power amplification is presented. An analysis of the intrinsic limitations of distributed power amplifiers serves as a guideline to present some solutions available in the literature. This analysis shows that a distributed amplifier can work as an optimum class-A power combiner for a discrete set of frequency values determined by the selected active devices, and the phase shift and characteristic impedances between stages. The solutions proposed over the years present several circuital configurations that offer different options for the distribution of the available gain-bandwidth product, which are briefly reviewed in this contribution.Este trabajo ha sido financiado por el Ministerio de Ciencia e Innovación (Programa Consolider-Ingenio 2010) en el marco del proyecto CSD2008-00066 (’EMET’-Engineering Metamaterials) y por la Junta de Andalucía por medio del proyecto P10-TIC-6883

Design Aspects of a Broadband Beam-Reconfigurable Leaky-Wave Antenna

Design aspects of a novel beam-reconfigurable pla-nar series-fed array are addressed to achieve beam steering with frequency tunability over a relatively broad bandwidth. The design is possible thanks to the use of the complementary strip-slot, which is an innovative broadly matched microstrip radiator, and the careful selection of the phase shifter parameters.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

DC-18 GHz MMIC tapered distributed power amplifier

A DC-18 GHz MMIC tapered power distributed amplifier has been designed and simulated in GaAs technology. The amplifier has been designed according to the theory for power and efficiency maximization based on tapered drain lines. Small- and large-signal simulations have been carried out to evaluate the amplifier’s behaviour. Results suggest that it is possible to achieve a good performance in terms of output power and efficiency for a wide bandwidth.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Distributed Amplifiers in MMIC Technology based on Composite Right/Left-Handed Transmision Lines

Abstract – Three MMIC distributed amplifiers based on Composite Right/Left-Handed Transmission Lines are presented in order to illustrate the actual performance of these devices, and the features that can be obtained with this distributed amplifier topology. Measurement results and/or qualified simulations have been included for two amplifiers with dual-band performance and for a high-power one. Also different frequency bands are illustrated, with examples at X-, C- and S-band operation.Universidad de Málaga.Campus de Excelencia Internacional Andalucía Tech. Ministerio de Ciencia e Innovación (Programa Consolider-Ingenio 2010) under Grant CSD2008-00066 (‘EMET’), and Junta de Andalucía (Spain) under Grant P10-TIC-6883

Desarrollo de un modelo no-lineal para HEMT de GaN incluyendo efectos térmicos

In this contribution the procedure to obtain a user-defined model for a commercial GaN HEMT (CGH35015 manufactured by Cree) is described. The developed model includes device thermal effects caused by power dissipation. Due to the lack of a complete set of device measurements, both pulsed I-V measurements and the simulated device performance obtained by using the model provided by the manufacturer have been employed. The result is an open model implemented in a commercial CAD tool (AWR Design Environment) that can be fully adjusted by the user and provides small, large-signal and self-heating phenomena simulation

On the system performance of DFT-S-OFDM and CP-OFDM for 5G Uplink in mmWave band

Both conventional Cyclic Prefix Orthogonal Frequency Division Multiplexing (CP-OFDM) and Discrete Fourier Transform Spread OFDM (DFT-S-OFDM) have been adopted for their use in the Physical Uplink Shared Channel (PUSCH) in the 5G New Radio (NR) standard. While CP-OFDM can better exploit the frequency characteristics of the channel, DFTS-OFDM has the advantage of a lower peak-to-average power ratio (PAPR). Due to the interactions between PAPR and power amplifier (PA) non-linearity, users adopting DFT-S-OFDM waveform may benefit from a potentially higher PA efficiency and extend their coverage by increasing their transmit power. In this paper we study the uplink performance of both waveforms and their interaction with non-linear PA and uplink power control in the millimeter-wave (mmWave) band to determine their optimal operational range

Extracción y validación de un modelo no-lineal para un dispositivo HEMT de GaN

In this contribution a non-linear model for a GaN 8x50 μm monolithic HEMT is described. Practical issues on model selection and parameter extraction procedure are assessed. The model has been validated by comparing measured and simulated results (up to 20 GHz) under large signal regime for a 4 GHz source. Once the simulation capability is confirmed the model is used to explore the possibilities of using the device in high-linear power amplifier applications such as WiMAX transmitter front-ends. Simulated results show that this device could be employed for such applications