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A 3-bit load-pulling digital power amplifier

Published online by Cambridge University Press:  01 June 2020

Gavin T. Watkins*
Affiliation:
Toshiba Research Europe Limited, 32 Queen Square, Bristol, BS1 4ND, England
*
Author for correspondence: Gavin T. Watkins, E-mail: gavin.watkins@toshiba-trel.com

Abstract

A radio frequency (RF) 3-bit digital power amplifier (DPA) is described in this paper. It consists of three RF amplifiers connected at their outputs with a transmission line (TL) network. The three amplifiers are designed for different output powers (POUT). The TL network allows them to load-pull one other to achieve eight different amplitude states by alternatively enabling and disabling the amplifiers via their gate bias. A prototype was designed in the National Instruments' Microwave Office (MWO) for 500 MHz with the aid of a genetic algorithm to optimize the TL network for all seven active (on-) states. The optimizer efficiencies goals were based on data derived from load-pull simulation. The POUT goals were based on a 1 Vrms step-size. In simulation, ≥50% efficiency was achieved at all on-states with 29.7 dBm peak POUT. A practical prototype based on the simulation achieved an efficiency of ≥40% over all seven on-states. A peak POUT of 28.9 dBm was achieved, with the lowest state at 22.4 dBm.

Type
Power Amplifiers
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2020

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References

Watkins, GT and Mimis, K (2018) How not to rely on Moore's Law alone: low-complexity envelope-tracking amplifiers. IEEE Microwave Magazine 19, 8494.CrossRefGoogle ScholarPubMed
Cidronali, A, Giovannelli, N, Maddio, S, Del Chiaro, A, Schuberth, C, Magesacher, T and Singerl, P (2016) A 280 W LDMOS broadband Doherty PA with 52% of fractional bandwidth based on a multi-line impedance inverter for DVB-T applications. International Journal of Microwave and Wireless Technologies 8, 11411153.CrossRefGoogle Scholar
Bogusz, A, Lees, J, Quaglia, R, Watkins, G and Cripps, SC (2018) Practical load compensation networks in Chireix outphasing amplifiers using offset transmission lines. 48th European Microwave Conference (EuMC), Madrid.CrossRefGoogle Scholar
Mimis, K and Watkins, GT (2015) Impact of time misalignment and input signal statistics in dynamically load-modulated amplifiers. International Journal of Microwave and Wireless Technologies 3–4, 11411153.Google Scholar
Wentzel, A, Hossain, M, Stoppel, D, Weimann, N, Krozer, V and Heinrich, W (2016) An efficient W-band InP DHBT digital power amplifier. International Journal of Microwave and Wireless Technologies 6, 12411249.Google Scholar
Fuhrmann, J, Moreira, J, Oßmann, P, Springer, A, Weigel, R and Pretl, H (2017) A 15-bit 28 nm CMOS fully-integrated 1.6W digital power amplifier for LTE IoT. 43rd IEEE European Solid-State Circuits Conference, Lenven.CrossRefGoogle Scholar
Bousnina, S (2009) Maximizing efficiency and linearity. IEEE Microwave Magazine 5, 99107.CrossRefGoogle Scholar
Li, T, Yin, Y, Zhu, Y, Xiong, L, Liu, Y, Yan, N, Min, H and Xu, H (2018) A wideband efficiency-enhanced class-G digital power amplifier for IoT applications. IEEE Microwave and Wireless Components Letters 8, 714716.CrossRefGoogle Scholar
Dietrich, F, Wei, M and Negra, R (2018) 450W sequential power amplifier with 60% efficiency at 10 dB back-off using active Doherty-type load modulation. 48th European Microwave Conference (EuMC), Madrid.CrossRefGoogle Scholar
Xu, H, Wang, G and Lu, K (2011) Microstrip Rat-Race couplers. IEEE Microwave Magazine 4, 117129.CrossRefGoogle Scholar
Arabi, E, Enrico de Falco, P, Birchall, J, Morris, KA and Beach, M (2017) Design of a triple-band power amplifier using a genetic algorithm and the continuous mode method. 2017 IEEE Topical Conference on RF/Microwave Power Amplifiers for Radio and Wireless Applications (PAWR), San Diego.CrossRefGoogle Scholar
Gulati, M, Siddhartha, S, Vedi, Y and Susila, M (2018) Genetic-algorithm based planar antenna design. International Conference on Wireless Communications, Signal Processing and Networking (WiSPNET).Google Scholar
Bhat, R and Krishnaswamy, H (2014) A watt-level 2.4 GHz RF I/Q power DAC transmitter with integrated mixed-domain FIR filtering of quantization noise in 65 nm CMOS. IEEE Radio Frequency Integrated Circuits Symposium, pp. 413416.Google Scholar
Watanabe, M and LaRocca, T (2012) A 3-bit, 2-watt, digital-analog gallium nitride power amplifier for 64-QAM bandwidth efficient modulation with 25% power savings. IEEE Radio Frequency Integrated Circuits Symposium, Montreal, pp. 229232.CrossRefGoogle Scholar
Quach, T, Watson, P, Dupaix, B, Barton, T, LaRue, M, Gouty, W and Khalil, W (2017) Wideband high-efficiency digital power amplifier in GaN. 12th European Microwave Integrated Circuits Conference, pp. 192195.CrossRefGoogle Scholar
Watkins, GT (2018) A class E digital transmitter for 16-APSK. 48th European Microwave Conference (EuMC), Madrid, pp. 13091312.Google Scholar
Hashemi, M, Shen, Y, Mehrpoo, M, Alavi, MS and de Vreede, LCN (2017) An intrinsically linear wideband polar digital power amplifier. IEEE Journal of Solid-State Circuits 12, 33123328.CrossRefGoogle Scholar
Shopov, S, Cahoon, N and Voinigescu, SP (2017) Ultra-broadband I/Q RF-DAC transmitters. IEEE Transactions on Microwave Theory and Techniques 12, 54115420.Google Scholar
Zhu, Y, Xiong, L, Yin, Y, Luo, W, Chen, B, Li, T and Xu, H (2018) A compact 2.4 GHz polar/quadrature reconfigurable digital power amplifier in 28 nm logic LP CMOS. IEEE Custom Integrated Circuits Conference (CICC), San Diego, pp. 14.Google Scholar