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Computationally efficient real-time digital predistortion architectures for envelope tracking power amplifiers

Published online by Cambridge University Press:  05 March 2013

Pere L. Gilabert  and
Gabriel Montoro
Pere L. Gilabert*
Affiliation:
Department of Signal Theory and Communications, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Esteve Terradas 7, 08860 Castelldefels, Barcelona, Spain
Gabriel Montoro
Affiliation:
Department of Signal Theory and Communications, Universitat Politècnica de Catalunya-BarcelonaTech, c/ Esteve Terradas 7, 08860 Castelldefels, Barcelona, Spain
*
Corresponding author: Pere L. Gilabert Email: [email protected]
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Abstract

This paper presents and discusses two possible real-time digital predistortion (DPD) architectures suitable for envelope tracking (ET) power amplifiers (PAs) oriented at a final computationally efficient implementation in a field programmable gate array (FPGA) device. In ET systems, by using a shaping function is possible to modulate the supply voltage according to different criteria. One possibility is to use slower versions of the original RF signal's envelope in order to relax the slew-rate (SR) and bandwidth (BW) requirements of the envelope amplifier (EA) or drain modulator. The nonlinear distortion that arises when performing ET with a supply voltage signal that follows both the original and the slow envelope will be presented, as well as the DPD function capable of compensating for these unwanted effects. Finally, two different approaches for efficiently implementing the DPD functions, a polynomial-based and a look-up table-based, will be discussed.

Keywords

Power amplifiers and linearizersModelingSimulation and characterizations of devices and circuits
Type
Research Papers
Information
International Journal of Microwave and Wireless Technologies , Volume 5 , Special Issue 2: Special Issue on Power Amplifier Linearization , April 2013 , pp. 187 - 193
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2013

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References

REFERENCES

[1]Kim, B.; Kim, I.; Moon, J.: Advance Doherty architecture. IEEE Microw. Mag., 11 (2010), 72–86.Google Scholar
[2]Raab, F.; Sigmon, B.; Myers, R.; Jackson, R.: L-band transmitter using Kahn EER technique. IEEE Trans. Microw. Theory Tech., 46 (1998), 2220–2225.CrossRefGoogle Scholar
[3]Wang, F. et al. : An improved power-added efficiency 19 dBm hybrid envelope elimination and restoration power amplifier for 802.11 g WLAN applications. IEEE Trans. Microw. Theory Tech., 54 (2006), 4086–4099.Google Scholar
[4]Taromaru, M.; Ando, N.; Kodera, T.; Yano, K.: An EER transmitter architecture with burst-width envelope modulation based on triangle wave comparison PWM, in Proc. IEEE Int. Symp. Personal, Indoor and Mobile Radio Communications (PIMRC’07), Athens, Greece, September 2007, 1–5.CrossRefGoogle Scholar
[5]Jeong, J.; Kimball, D.F.; Kwak, M.; Hsia, C.; Draxler, P.; Asbeck, P.M.: Wideband envelope tracking power amplifiers with reduced bandwidth power supply waveform and adaptive digital predistortion techniques. IEEE Trans. Microw. Theory Tech., 57 (2009), 3307–3314.Google Scholar
[6]Mustafa, A.K.; Bassoo, V.; Faulkner, M.: Reducing drive signal bandwidths of EER microwave power amplifiers, in IEEE MTT Int. Microwave Symp. (IMS 2009), Boston, USA.Google Scholar
[7]Kim, J.; Konstantinou, K.: Digital predistortion of wideband signals based on power amplifier model with memory. Electron. Lett., 37 (23) (2001), 1417–1418.Google Scholar
[8]Montoro, G.; Gilabert, P.L.; Bertran, E.; Berenguer, J.: A method for real-time generation of slew-rate limited envelopes in envelope tracking transmitters, in IEEE Int. Microwave Series on RF Front-ends for Software Defined and Cognitive Radio Solutions, Aveiro, Portugal, February 2010, 1–4.Google Scholar
[9]Gilabert, P.L.; Montoro, G.: Look-up table implementation of a slow envelope dependent digital predistorter for envelope tracking power amplifiers. IEEE Microw. Wirel. Compon. Lett., 22 (2) (2012), 97–99.Google Scholar
[10]Montoro, G.; Gilabert, P.L.; Berenguer, J.; Bertran, E.: Digital predistortion of envelope tracking amplifiers driven by slew-rate limited envelopes, in IEEE Int. Microwave Symp. (IMS’2011), Baltimore, USA, June 2011.Google Scholar
[11]Wimpenny, G.: Envelope Tracking PA Characterisation. White Paper. Open ET Alliance (http://www.open-et.org). November 2011.Google Scholar
[12]Hanington, G.; Chen, P.-F.; Asbeck, P.M.; Larson, L.E.: High-efficiency power amplifier using dynamic power-supply voltage for CDMA applications. IEEE Trans. Microw. Theory Tech., 47 (1999), 1471–1476.CrossRefGoogle Scholar
[13]Hoversten, J.; Schafer, S.; Roberg, M.; Norris, M.; Maksimovic, D.; Popovic, Z.: Codesign of PA, supply, and signal processing for linear supply-modulated RF transmitters. IEEE Trans. Microw. Theory Tech., 60 (2012), 2010–2020.CrossRefGoogle Scholar
[14]Vizarreta, P.; Montoro, G.; Gilabert, P.A.: Hybrid envelope amplifier for envelope tracking power amplifier transmitters, in European Microwave Conf. (EuMC’12), Amsterdam, Holland, November 2012, 1–4.Google Scholar
[15]Gilabert, P.L.; Montoro, G.; Vizarreta, P.: Slew-rate and efficiency trade-off in slow envelope tracking power amplifiers, in German Microwave Conf. (GeMiC'12), Ilmenau, Germany, March 2012, 1–4.Google Scholar
[16]Mrabet, N.; Mohammad, I.; Mkadem, F.; Rebai, C.; Boumaiza, S.: Optimized hardware for polynomial digital predistortion system implementation, in IEEE Topical Conf. on Power Amplifiers for Wireless and Radio Applications (PAWR), Santa Clara, USA, January 2012, 81–84.CrossRefGoogle Scholar
[17]Gilabert, P.L.; Montoro, G.; Bertran, E.: FPGA implementation of a real-time NARMA-based digital adaptive predistorter. IEEE Trans. Circuits Syst. II, 57 (2011), 402–406.Google Scholar
[18]Julius, S.; Dinh, A.: Evaluation of a digital predistortion on FPGA for power amplifier linearization, in IEEE Canadian Conf. on Electrical and Computer Eng. (CCECE), Montreal, Canada, May 2011, 660–664.Google Scholar