Doherty Power Amplifier at 2.4 GHz to

improve harmonic response using filter

characteristics

Ajinkya C. Kulkarni

ajinkyackulkarni@gmail.com

Outline: Concept

Carrier

Amplifier

Peaking

Amplifier

Po

wer

Sp

litt

erOffset Lines

Qu

art

er W

av

e

Tra

nsf

orm

er

Lo

ad

Quarter Wave

Transformer

Input

Ou

tpu

t

Amplifiers used in cellular base stations

[3] R. Giofrè, L. Piazzon, P. Colantonio and F. Giannini, “Being Seventy-Five Still Young: The Doherty Power Amplifier,”

Microwave Journal, April 2012, pp. 72-88.

[4] Bumman Kim, Jangheon Kim, Ildu Kim, and Jeonghyeon Cha, “The Doherty Power Amplifier,” IEEE Microwave

Magazine, Oct. 2006, pp. 42-50. [5]

Pre 2003

2003-2005

2005 20102010-

Present

Feed-forward

Class AB

Class AB with DPD

Doherty with memory

based DPD

Enhanced Video

bandwidth

Doherty and its

novel approaches

Doherty Power Amplifier

[6] W. H. Doherty, “New High Efficiency Power Amplifier for Modulated Waves,” Proceedings of Institute of Radio

Engineers, vol.24, no.9, pp. 1163-1182, Sept.1936

[3] and Internet Source: http://en.wikipedia.org/wiki/Doherty_amplifier

Aug 21, 1907 - Feb 15, 2000

• Invented by William H. Doherty at Bell Labs in

1936

• Originally, class B carrier and class B peaking

amps (both tubes, of course, its 1930’s)

• Later modified by Joseph B. Sainton of Continental

Microwave, giving it a form it today has.

Doherty Amplifier Architecture

Carrier Amplifier

Peaking Amplifier

Po

wer

Sp

litt

erOffset Lines

Qu

art

er W

av

e

Tra

nsf

orm

er

Lo

ad

Quarter Wave

Transformer

Input

Ou

tpu

t

Low power: peaking amp pinched off, representing open circuit at recombination point

High power: carrier amp remains saturated, peaking adapts load and reaches maxefficiency

Typically class C

Typically class AB

Doherty Amplifier operation

[7] Joongjin Nam, Jin-Ho Shin, and Bumman Kim, “A Handset Power Amplifier With High Efficiency at a

Low Level Using Load-Modulation Technique,” IEEE Transactions on Microwave Theory and Techniques,

vol. 53, no. 8, August 2005, pp. 2639-2644. [4] and [8]

Doherty Amplifier

working can be

explained using load

modulation

principle.

Fig. Reproduced from: [7]

Device Selection: CGH40010, GaN HEMT:

Large Signal Model

[38], [41], [42]

[43] Kazutaka Inoue et al., “High Power and High Efficiency GaN-HEMT for Microwave

Communication Applications,” IMWS-IWPT2011 Proceedings, pp. 267-270.

Doherty power amplifier design: 50:50 power split

ratio

Ref. [55]

Inverted Doherty Power Amplifier

Carrier

Amplifier

Po

wer

Sp

litt

er

Offset Lines

Qu

art

er W

av

e

Tra

nsf

orm

er

Lo

ad

Quarter Wave

Transformer

Input

Output

Peaking

Amplifier

[56] Karun Rawat , Fadhel Ghannouchi, “Load-pull Assisted CAD Design of Inverted Doherty Amplifier without Quarter-

wave Transformer,” presented at 25th IEEE Canadian Conference on Electrical and Computer Engineering (CCECE), 2012.

Selected Amplifier: Inverted Doherty Power

Amplifier: 70:30 power split ratio

Designing the Layout

Measurement Set Up

Response from the amplifier: Signal Spectrum

Response from the amplifier: C/N ratio

Response from the amplifier: Small signal gain

References 1

1. Frank Amoroso, “Spectral Sidelobe Regrowth in Saturating Amplifiers,” Applied Microwave and

Wireless, March 1998, pp. 36-42.

2. Hasan, Z. ,Boostanimehr, H. ; Bhargava, V.K., “Green Cellular Networks: A Survey, Some Research

Issues and Challenges,” Communication Surveys and Tutorials, IEEE, vol.13, no.4, pp. 524-540, Fourth

Quarter 2011.

3. R. Giofrè, L. Piazzon, P. Colantonio and F. Giannini, “Being Seventy-Five Still Young: The Doherty

Power Amplifier,” Microwave Journal, April 2012, pp. 72-88.

4. Bumman Kim, Jangheon Kim, Ildu Kim, and Jeonghyeon Cha, “The Doherty Power Amplifier,” IEEE

Microwave Magazine, Oct. 2006, pp. 42-50.

5. Damon Holmes, “Doherty Power Amplifier Theory and Design for Cellular Infrastructure Applications,”

presented at EDI CON 2013, Beijing China.

6. W. H. Doherty, “New High Efficiency Power Amplifier for Modulated Waves,” Proceedings of Institute

of Radio Engineers, vol.24, no.9, pp. 1163-1182, Sept.1936.

7. Joongjin Nam, Jin-Ho Shin, and Bumman Kim, “A Handset Power Amplifier With High Efficiency at a

Low Level Using Load-Modulation Technique,” IEEE Transactions on Microwave Theory and

Techniques, vol. 53, no. 8, August 2005, pp. 2639-2644.

8. Paolo Colantonio, Franco Giannini, and Ernesto Limiti, High Efficiency RF and Microwave Solid State

Power Amplifiers, A John Wiley and Sons Ltd., Publication, 2009, pp. 131-160.

9. Christopher Burns, “Highly efficient amplifier shows the promise of Doherty architecture.” Internet:

www.rfdesign.com [June 2007]

10. Bumman Kim, Ildu Kim, and Junghwan Moon, “Advanced Doherty Architecture,” IEEE Microwave

Magazine, August 2010, pp. 72-86.

References 2

11. R. Giofrè, L. Piazzon, P. Colantonio and F. Giannini, “Being Seventy-Five Still Young: The Doherty Power

Amplifier,” Microwave Journal, April 2012, pp. 72-88.

12. P. Colantonio, F. Giannini, R. Giofrè and L. Piazzon, “The Doherty Power Amplifier,” International Journal of

Microwave and Optical Technology, vol.5, no.6, November 2010, 415-430.

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vol. BC-33, no. 3, September 1987, pp. 77-83.

14. Youngoo Yang, Jaehyok Yi, Young Yun Woo, and Bumman Kim, “Experimental Investigation on Efficiency and

Linearity of Microwave Doherty Amplifier,” Microwave Symposium Digest (MTT), 2001 IEEE MTT-S

International, 2001, vol. 2, pp. 1367-1370.

15. Bumman Kim, Jangheon Kim, Ildu Kim, and Jeonghyeon Cha, “The Doherty Power Amplifier,” IEEE

Microwave Magazine, Oct. 2006, pp. 42-50.

16. Paolo Colantonio, Franco Giannini, Rocco Giofrè and Luca Piazzon, edited by Vitaliy Zhurbenko, Advanced

Microwave Circuits and Systems, InTech Publishers, pp.107-132.

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Amplifiers,” White Paper, Harris Corp., Broadcast Communications Division, Englewood, CO USA, 5 July,

2011.

18. David W. Runton, Michael LeFevre, Christopher Burns, “200W GaN Broadband, Quick-turn Doherty

Amplifier,” RF Micro Devices Chandler, AZ, Feb. 2012.

19. Li-Yuan Yang, Hsin-Shu Chen et al., “A 2.4 GHz Fully Integrated Cascode-Cascade CMOS Doherty Power

Amplifier,” IEEE Microwave and Wireless Components Letters, vol. 18, no. 3, March 2008, pp. 197-199.

20. JorgeMorenoRubio et al., “ A 22 W 65% efficiency GaN Doherty power amplifier at 3.5GHz for WiMAX

applications,” IEEE Integrated Nonlinear Microwave and Millimetre-wave Circuits (INMMiC 2011), April 18th -

19th, 2011 in Vienna, Austria.

References 3

21. Kenle Chen et al., “Design of Adaptive Highly Efficient GaN Power Amplifier for Octave-Bandwidth

Application and Dynamic Load Modulation,” IEEE Transactions on Microwave Theory and Techniques, vol. 60,

no. 6, June 2012, pp. 1829-1839.

22. Khaled Bathich, Georg Boeck, “Wideband Harmonically-Tuned GaN Doherty Power Amplifier,” IEEE MTT-S

2012 International Microwave Symposium, Montreal, Canada.

23. Heung-Jae Choi et al., “Doherty Amplifier Using Load Modulation and Phase Compensation DGS Microstrip

Line,” Proceedings of the 36th European Microwave Conference, Sept. 2006, Manchester UK.

24. Jangheon Kim et al., “Advanced Design Methods of Doherty Amplifier for Wide Bandwidth, High Efficiency

Base Station Power Amplifiers,” 35th Europian Microwave Conference, 2005, Paris, pp. 963-966.

25. Jangheon Kim et al., “A Saturated Doherty Power Amplifier Based On Saturated Amplifier,” IEEE Microwave

and Wireless Components Letters, vol. 20, no. 2, February 2010, pp. 109-111.

26. Simon Wood, Ray Pengelly et al., “High-Power, High-Efficiency GaN HEMT Power Amplifiers for 4G

Applications,” High Frequency Electronics, May 2009, pp. 36-48.

27. Rocco Giofrè, Luca Piazzon, Paolo Colantonio, Franco Giannini, “Focusing on Doherty Power Amplifiers for S-

Band,” MIKON 2012, 19th International Conference on Microwaves, Radar and Wireless Communications,

Warsaw, Poland, 21-23 May, 2012, pp. 186-189.

28. R. W. Zhou, Y. Dong, and J. F. Bao, “A 460mhz Doherty Amplifier For IMT-Advanced System,” Progress in

Electromagnetics Research Letters, vol. 32, June 2012, pp.187-195.

29. Junghwan Moon et al., “Doherty Amplifier with Envelope Tracking for High Efficiency,” Microwave

Symposium Digest (MTT), 2010 IEEE MTT-S International, 23 28 May, 2010, pp. 1086-1089.

30. Junghwan Moon, Jangheon Kim, Ildu Kim, Jungjoon Kim, and Bumman Kim, “Highly Efficient Three-Way

Saturated Doherty Amplifier With Digital Feedback Predistortion,” IEEE Microwave and Wireless Components

Letters, vol. 18, no. 8, August 2008, pp. 539-541.

References 4

31. Asdesach Z. Markos and GUnter Kompa, “High Power Doherty Amplifier Design for UMTS Application,” Microwave

Conference (GeMIC), 2008, German, 10-12 March, 2008, pp. 1-4.

32. Craig Steinbeiser, Thomas Landon, Charles Suckling, “250W HVHBT Doherty with 57% WCDMA Efficiency

Linearized to -55dBc for 2c11 6.5dB PAR,” Compound Semiconductor Integrated Circuit Symposium, CSIC 2007,

IEEE, 14-17 Oct., 2007, pp. 1-4.

33. Ildu Kiml, and Bumman Kim, “A 2.655 GHz 3-stage Doherty Power Amplifier using Envelope Tracking Technique,”

Microwave Symposium Digest (MTT), 2010 IEEE MTT-S International, 23-28 May, 2010, pp. 1496-1498.

34. Hiroaki Deguchi, Norihiko Ui, Kaname Ebihara, Kazutaka Inoue, Norihiro Yoshimura and Hidenori Takahashi, “A 33W

GaN HEMT Doherty Amplifier with 55% Drain Efficiency for 2.6GHz Base Stations,” Microwave Symposium Digest

(MTT), 2009 IEEE MTT-S International, 7-12 June, 2009, pp. 1273-1276.

35. John Dunn, Mark Saffian, “Simulating an NXP Doherty Amplifier with Digital Pre-Distortion,” Presented at EDI CON

2013.

36. KenleChen, Xiaoguang Liu, William J. Chappell and Dimitrios Peroulis, “Co-Design of Power Amplifier and

Narrowband Filter using High-Q Evanescent-Mode Cavity Resonator as the Output Matching Network ,” IEEE MTT-S

International Microwave Symposium, 2011, Baltimore, MD, USA.

37. Hyoungjong Kim, Gilwong Choi, and Jinjoo Choi, “Pulse Operation of an Inverse Class-F GaN Power Amplifier,”

Proceedings of the 38th European Microwave Conference, Amsterdam, The Netherlands, October 2008, pp. 1177-1180.

38. KenleChen, DimitriosPeroulis, “ Design of Highly Efficient Broadband Class-E Power Amplifier Using Synthesized

Low-Pass Matching Networks, ” IEEE Transactions on Microwave Theory and Techniques, Vol. 59, No. 12, December

2011.

39. Arvind Raghavan, Deukhyoun Heo, Moonkyun Maeng, Albert Sutono, Kyutae Lim and Joy Laskar, “A 2.4 GHz High

Efficiency SiGe HBT Power Amplifier with High-Q LTCC Harmonic Suppression Filter,” IEEE MTT-S Digest, 2002,

pp. 1019-1022.

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Artech House, 1980, pp. 255-353.

References 5

41. U. H. Andre et al., “High Efficiency, High Linearity GaN HEMT Amplifiers for WiMAX Applications,”

High Frequency Electronics, June 2007, pp. 16-30.

42. S. Wood et al., “High Efficiency, High Linearity GaN HEMT Amplifiers for WiMAX Applications,”

High Frequency Electronics, May 2006, pp.22-36.

43. Kazutaka Inoue et al., “High Power and High Efficiency GaN-HEMT for Microwave Communication

Applications,” IMWS-IWPT2011 Proceedings, pp. 267-270.

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Systems Series, vol. 1, pp. 183-243.

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Symposium, Amsterdam, 2004, pp. 187-190.

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IEEE Transactions on Microwave Theory and Techniques, vol. 57, no. 8, August 2009.

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250PBRN,” Application Note, NXP Semiconductors, 14, March 2011.

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References 6

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Frequency Electronics, January 2008, pp. 42-54.

52. Andrei Grebennikov, “Power Combiners, Impedance Transformers and Directional Couplers: Part III,” High

Frequency Electronics, Feb. 2008, pp. 42-52.

53. Youngoo Yang, Jaehyok Yi, Young Yun Woo and Bumman Kim, “Optimum Design for Linearity and Efficiency

of a Microwave Doherty Amplifier Using a New Load Matching Technique,” Pohang University of Science and

Technology Pohang, Korea.

54. Roberto Quaglia, Marco Pirola and Chiara Ramella, “Offset Lines in Doherty Power Amplifiers: Analytical

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56. Karun Rawat , Fadhel Ghannouchi, “Load-pull Assisted CAD Design of Inverted Doherty Amplifier without

Quarter-wave Transformer,” presented at 25th IEEE Canadian Conference on Electrical and Computer

Engineering (CCECE), 2012.

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GHz frequency range”, 2003.

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Technology International, February 2012.a

Thank you!