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An envelope tracking RF power amplifier with capacitive charge pump modulator

Published online by Cambridge University Press:  06 April 2016

Gavin Tomas Watkins  and
Konstantinos Mimis
Gavin Tomas Watkins*
Affiliation:
Toshiba Research Europe Limited, 32 Queen Square, Bristol BS1 4ND, UK. Phone: +44 (0)117 906 0740
Konstantinos Mimis
Affiliation:
Toshiba Research Europe Limited, 32 Queen Square, Bristol BS1 4ND, UK. Phone: +44 (0)117 906 0740
*
Corresponding author:G. T. Watkins Email: [email protected]
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Abstract

An envelope tracking (ET) radio frequency (RF) power amplifier (PA) is described intended for handsets and applications where a large number of PAs are needed. Instead of the usual split frequency architecture, a linear tracking charge pump structure is proposed. This allows the supply voltage of an RF PA to increase during the peaks of a high peak-to-average power ratio signal. When combined with an LDMOS RF PA, 42.9% efficiency was achieved at 31.3 dBm output power (POUT) when amplifying a 5 MHz bandwidth 8 dB PAPR 3rd Generation Partnership Project (3GPP) long term evolution signal. The first channel adjacent power ratio (ACPR) without digital pre-distortion was −30.4 dBc, meeting the 3GPP handset emission mask. The ACPR could be improved to −32.5 dBc by adopting a curved envelope shaping function at a reduced efficiency of 38.9%.

Keywords

Circuit design and applicationsPower amplifiers and linearizers
Type
Research Papers
Information
International Journal of Microwave and Wireless Technologies , Volume 8 , Special Issue 4-5: EuMW 2015 Special Issue , June 2016 , pp. 683 - 690
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2016 

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References

REFERENCES

[1]3GPP TS 36.211 E-UTRA specifications. Available from http://www.3gpp.org, viewed 29 March 2016.Google Scholar
[2]IEEE 802.11 Wireless LAN specifications. Available from http://standards.ieee.org/, viewed 29 March 2016.Google Scholar
[3]The DVB Project ETSI EN 302 755 specifications. Available from http://www.etsi.org, viewed 29 March 2016.Google Scholar
[4] Hone, T. et al. : Optimized load modulation in a Doherty amplifier using a current injection technique, 2011 European Microwave Integrated Circuits Conf. (EuMIC), Manchester, UK, 2011, 296–299.Google Scholar
[5] Hone, T.M.; Aref, A.F.; Guan, J.; Negra, R.: Noncontiguous LTE channel amplification using a multilevel outphasing transmitter, 2014 German Microwave Conf. (GeMIC), Aachen, Germany, 2014, 1–4.Google Scholar
[6] Mimis, K.; Watkins, G.T.: Impact of time misalignment and input signal statistics in dynamically load-modulated amplifiers. Int. J. Microw. Wireless Technol., 7 (2015), 327–337.CrossRefGoogle Scholar
[7] Kim, B. et al. : Pushing the envelope, IEEE Microwave Magazine, IMS Special Issue, May 2013, 68–81.CrossRefGoogle Scholar
[8]Nujira white paper: The market opportunities for envelope tracking. Available online, published Sep. 2014.Google Scholar
[9] Watkins, G.T.; Mimis, K.: Low Complexity Charge Pump Envelope Tracking RF Power Amplifier, 2015 European Microwave Conf. (EuMC), Paris, UK, 2015, 92–95.CrossRefGoogle Scholar
[10] Augeau, P. et al. : A New GaN-Bsed high-swpeed and high-power switched circuit for envelope-tracking modulators. Int. J. Microw. Wireless Technol., 6 (1) (2013), 13–21.CrossRefGoogle Scholar
[11] Walling, J.S.; Taylor, S.S.; Allstot, J.D.: A class-G supply modulator and class E-PA in 130 nm CMOS. IEEE J. Solid-State Circuits, 44 (9) (2009), 2339–2347.CrossRefGoogle Scholar
[12] Kim, J.H.; Son, H.S.; Kim, W.Y.; Park, C.S.: Envelope amplifier with multiple-linear regulator for envelope tracking power amplifier. IEEE Trans. Microw. Theory Tech., 61 (11) (2013), 3951–3960.CrossRefGoogle Scholar
[13]National Instrument white paper: 5 G massive MIMO testbed: from theory to reality. Available online, published 1st Oct. 2014.Google Scholar
[14] Marston, R.: Newnes Electronics Circuit Pocket Book. Butterworth-Heinemann, 1993, 159–162. ISBN 0750608579.Google Scholar
[15] Watkins, G.: Inductor-less envelope modulated RF PA using stacked amplifiers and envelope shaping. IET Microw. Antennas Propag., 7 (15) (2013), 1215–1220.CrossRefGoogle Scholar
[16] McCune, E.: Operating modes of dynamic power supply transmitter amplifiers. IEEE Trans. Microw. Theory Tech., 62 (11) (2014), 2511–2517.CrossRefGoogle Scholar
[17] Sedra, A.S.; Smith, K.C.: Microelectronic Circuits . Oxford University Press, 1991, 880–882. ISBN 0195103696.Google Scholar
[18] Kim, B.; Moon, J.; Kim, J.: A Multimode/Multiband Envelope Tracking Transmitter with Broadband Saturated Amplifier, Telsiks, Serbia, 2011, 215–221.Google Scholar
[19] Watkins, G.T.; Mimis, K.: Impact of Envelope Shaping on the Linearity of Envelope Tracking Transmitters, 2nd Annual Active and Passive RF Devices Seminar, Birmingham, UK, 2014, 29–32.Google Scholar
[20] Rahkonen, T.; Hietakangas, S.; Aikio, J.: AM-PM distortion caused by transistor's signal dependent input impedance, IEEE 20th European Conf. on Circuit Theory and Design (ECCTD), 2011, 833–836.CrossRefGoogle Scholar
[21] Yan, J.J.; Draxler, P.; Presti, C.D.; Kimball, D.F.; Asbeck, P.M.: Digital prediction of envelope-tracking power amplifiers under average power back-off and long-term average power efficiency for base-station applications. Int. J. Microw. Wireless Technol., 5 (2) (2013), 171–177.CrossRefGoogle Scholar
[22] Kang, D. et al. : A 34% PAE, 26-dBm output power envelope-tracking CMOS power amplifier for 10-MHz BW LTE applications, 2012 IEEE MTT-S Int. Microwave Symp. Digest (MTT), Montréal, Canada, 2012, 1–3.CrossRefGoogle Scholar
[23] Kim, H. et al. : Efficiency enhancement amplifier using a digitally-controlled dynamic bias switching circuit. Microw. J., 56 (2013), 106–120.Google Scholar
[24] Modi, S.S.; Balsara, P.T.; Eliezer, O.E.: Reduced bandwidth class H supply modulation for wideband RF power amplifiers, 2012 IEEE 13th Annual Wireless and Microwave Technology Conf. (WAMICON), Florida, USA, 2012, 1–7.CrossRefGoogle Scholar
[25] Hiura, S.; Sumi, H.; Takahashi, H.: High-efficiency 400 W power amplifier with dynamic drain votlage control for 6 MHz OFDM signal, 2010 IEEE MTT-S Int. Microwave Symp. Digest (MTT), Anaheim, USA, 2010, 936–939.CrossRefGoogle Scholar
[26] Bracle, A.; Rathgeber, L.; Siegert, F.; Heck, S.; Berroth, M.: Power supply modulation for RF applications, EPE-PEMC 2012 ECCE Europe, 15th Int. Power Electronics and Motion Control Conf., Movi Sad, Serbia, 2012, LS8d.3–1–LS8d.3–5.CrossRefGoogle Scholar