Hostname: page-component-7479d7b7d-pfhbr Total loading time: 0 Render date: 2024-07-12T13:28:42.185Z Has data issue: false hasContentIssue false
  • English
  • Français

Design and analysis of 80-W wideband asymmetrical Doherty amplifier

Published online by Cambridge University Press:  01 April 2014

Khaled Bathich  and
Georg Boeck
Khaled Bathich*
Affiliation:
Microwave Engineering Laboratory, Berlin Institute of Technology, Einsteinufer 25, D-10587, Berlin, Germany
Georg Boeck
Affiliation:
Microwave Engineering Laboratory, Berlin Institute of Technology, Einsteinufer 25, D-10587, Berlin, Germany
*
Corresponding author: K. Bathich Email: khaled.bathich@novero.com
Get access Rights & Permissions [Opens in a new window]

Abstract

This paper presents the analysis and design of a wideband asymmetrical Doherty amplifier. The frequency response of the output combining network of the Doherty amplifier with arbitrary back-off level configuration is analyzed. Other bandwidth-limiting factors were discussed and analyzed as well. A number of performance enhancement techniques were taken into consideration to obtain high and flat back-off efficiency over the amplifier design band of 1.7–2.25 GHz. The designed Doherty amplifier had, at 8.0–9.9 dB output back-off, a minimum efficiency of η = 50% [power-added efficiency of 45%], measured near 40 dBm of output power, and over 28% bandwidth. Using digital predistortion (DPD) linearization, an adjacent-channel leakage ratio (ACLR) of −43 dBc was obtained for a single-carrier W-CDMA signal, at 40.9 dBm and 46% of average output power and drain efficiency, respectively. The designed amplifier represents the first wideband Doherty amplifier reported over extended power back-off range.

Keywords

Power amplifiers and linearizersCircuit design and applications
Type
Research Papers
Information
International Journal of Microwave and Wireless Technologies , Volume 7 , Issue 1 , February 2015 , pp. 13 - 18
Copyright
Copyright © Cambridge University Press and the European Microwave Association 2014 

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

[1]Doherty, W.H.: A new high efficiency power amplifier for modulated waves. Proc. IRE, 24 (1936), 1163–1182.CrossRefGoogle Scholar
[2]Cripps, S.C.: Advanced Techniques in RF Power Amplifier Design, Artech House, Norwood, MA, (2002).Google Scholar
[3]Raab, F.H.: Efficiency of Doherty RF power-amplifier systems. IEEE Trans. Broadcast., BC-33 (3) (1987), 77–83.CrossRefGoogle Scholar
[4]Raab, F.H. et al. : Power amplifiers and transmitters for RF and microwave. IEEE Trans. Microw. Theory Tech., 50 (3) (2002), 814–826.CrossRefGoogle Scholar
[5]Bathich, K.; Markos, A.Z. and Boeck, G.: Frequency response analysis and bandwidth extension of the Doherty amplifier. IEEE Trans. Microw. Theory Tech., 59 (4) (2011), 934–944.CrossRefGoogle Scholar
[6]Sun, G. and Jansen, R.H.: Broadband Doherty power amplifier via real frequency technique. IEEE Trans. Microw. Theory Tech., 60 (1) (2012), 99–111.CrossRefGoogle Scholar
[7]Bathich, K. and Boeck, G.: Wideband harmonically-tuned GaN Doherty power amplifier, in IEEE MTT-S Int. Microwave Symp. Digest, June 2012.CrossRefGoogle Scholar
[8]Kang, D.; Kim, D.; Moon, J. and Kim, B.: Broadband HBT Doherty power amplifiers for handset applications. IEEE Trans. Microw. Theory Tech., 58 (12) (2010), 4031–4039.CrossRefGoogle Scholar
[9]Wu, D.Y.-T. and Boumiza, S.: A modified Doherty configuration for broadband amplification using symmetrical devices. IEEE Trans. Microw. Theory Tech., 60 (10) (2012), 3201–3213.CrossRefGoogle Scholar
[10]Bathich, K.; Markos, A.Z. and Boeck, G.: A wideband GaN Doherty amplifier with 35% fractional bandwidth, in Proc. 40th Eur. Microwave Conf., Paris, France, September 2010, 1006–1009.Google Scholar
[11]Kim, J.; Son, J.; Moon, J. and Kim, B.: A saturated Doherty power amplifier based on saturated amplifier. IEEE Microw. Wireless Compon. Lett., 20 (2) (2010), 109–111.CrossRefGoogle Scholar
[12]Moon, J.; Kim, J.; Kim, I.; Kim, J. and Kim, B.: A wideband envelope tracking Doherty amplifier for WiMAX systems. IEEE Microw. Wireless Compon. Lett., 18 (1) (2008), 49–51.CrossRefGoogle Scholar
[13]Lee, Y.-S.; Lee, M.-W.; Kam, S.-H. and Jeong, Y.-H.: A new wideband Distributed Doherty amplifier for WCDMA repeater applications. IEEE Microw. Wireless Compon. Lett., 19 (10) (2009), 668–670.Google Scholar
[14]Qureshi, J.H.; Li, N.; Neo, W.C.E.; van Rijs, F.; Blednov, I. and de Vreede, L.C.N.: A wide-band 20W LDMOS Doherty power amplifier, in IEEE MTT-S Int. Microwave Symp. Digest, May 2010, 1504–1507.CrossRefGoogle Scholar
[15]Ericsson: LTE-An Introduction, June (2009).Google Scholar
[16]Darraji, R.; Ghannouchi, F.M. and Hammi, O.: A dual-input digitally driven Doherty amplifier architecture for performance enhancement of Doherty transmitters. IEEE Trans. Microw. Theory Tech., 59 (5) (2011), 1284–1293.CrossRefGoogle Scholar
[17]Kang, D.; Kim, D.; Cho, Y.; Park, B.; Kim, J. and Kim, B.: Design of bandwidth-enhanced Doherty power amplifiers for handset applications. IEEE Trans. Microw. Theory Tech., 59 (12) (2011), 3474–3483.CrossRefGoogle Scholar
[18]Lee, J.-Y.; Kim, J.-Y.; Kim, J.-H.; Cho, K.-J. and Stapleton, S.P.: A high power asymmetric Doherty amplifier with improved linear dynamic range, in IEEE MTT-S Int. Microwave Symp. Digest, June 2006, 1348–1351.CrossRefGoogle Scholar
[19]Kitahara, T.; Yamamoto, T. and Hiura, S.: Doherty power amplifier with asymmetrical drain voltages for enhanced efficiency at 8 dB backed-off output power, in IEEE MTT-S Int. Microwave Symp. Digest, June 2011.CrossRefGoogle Scholar