Broadband Baseband Impedance Control for Linearity Enhancement in Microwave Devices
The out-of-band impedance environment is considered
to be of paramount importance in engineering the in-band impedance
environment. Presenting the frequency independent and constant outof-
band impedances across the wide modulation bandwidth is
extremely important for reliable device characterization for future
wireless systems. This paper presents an out-of-band impedance
optimization scheme based on simultaneous engineering of
significant baseband components IF1 (twice the modulation
frequency) and IF2 (four times the modulation frequency) and higher
baseband components such as IF3 (six times the modulation
frequency) and IF4 (eight times the modulation frequency) to
engineer the in-band impedance environment. The investigations
were carried out on a 10W GaN HEMT device driven to deliver a
peak envelope power of approximately 40.5dBm under modulated
excitation. The presentation of frequency independent baseband
impedances to all the significant baseband components whilst
maintaining the optimum termination for fundamental tones as well
as reactive termination for 2nd harmonic under class-J mode of
operation has outlined separate optimum impedances for best
intermodulation (IM) linearity.
[1] Joel Vuolevi and Timo Rahkonen, Distortion in RF Power Amplifiers,
Norwood, MA: Artech House, 2003.
[2] B. Kenington, High-Linearity RF Amplifier Design, Norwood, MA:
Artech House, 2000.
[3] C. Fan and K. M. Cheng, “Theoretical and experimental study of
amplifier linearization based on harmonic and baseband signal injection
technique,” IEEE Trans. Microwave Theory Tech., vol. 50, pp. 1801–
1806, July 2002.
[4] J. Vuolevi, J. Manninen, T. Rahkonen, “Cancelling the memory effects
in RF power amplifiers”, IEEE International Circuits and Systems
Symposium, 2001, pp. 57–60.
[5] S. C. Cripps, Advanced Techniques in RF Power Amplifier Design,
Norwood, MA, Artech House, 2006.
[6] M. D. LeFevre, D. W. Runton, C. T. Burns, M. K. Mellor, “Digital
Predistortion from an RF Perspective”, 2010 IEEE Topical Symposium
on Power Amplifiers for Wireless Communications, September 2010.
[7] Z. Yusoff, J. Lees, P. J. Tasker, J. Benedikt, S.C. Cripps, “Linearity
Improvement in RF Power Amplifier System Using Integrated Auxiliary
Envelope Tracking System”, in Proc. of IEEE MTT-S International,
June 2011, pages: 1 -4.
[8] A. Alghanim, J. Benedikt, P.J. Tasker, P “A measurement test-set for
characterisation of high power LDMOS transistors including memory
effects” Proceedings of High Frequency Postgraduate Student
Colloquium, 5-6 September 2005 Page(s): 29 – 32. [9] A. Alghanim, J. Lees,T. Williams, J. Benedikt, P.J. Tasker, “Using
active IF load-pull to investigate electrical base-band induced memory
effects in high-power LDMOS transistors,” in Proc. Asia-Pacific
Microwave Conference, 2007, 11-14 Dec. 2007 Page(s):1 - 4.
[10] J. Lees, T. Williams, S. Woodington, P. McGovern, S. Cripps, J.
Benedikt, and J. Tasker, “Demystifying Device related Memory Effects
using Waveform Engineering and Envelope Domain Analysis,”
European Microwave Conf., Oct. 2008, Amsterdam, pp:753-756.
[11] A. Alghanim, J. Lees,T. Williams, J. Benedikt, P.J. Tasker, P “Using
active IF load-pull to investigate electrical base-band induced memory
effects in high-power LDMOS transistors,” Proceedings of Asia-Pacific
Microwave Conference, December 2007, Page(s):1 - 4.
[12] M. Akmal, J. Lees, S. Bensmida, S. Woodington, J. Benedikt, K. Morris,
M. Beach, J. McGeehan, P. J. Tasker, “ The Impact of Baseband
Electrical Memory Effects on the Dynamic Transfer Characteristics of
Microwave Power Transistors”, in Proc. of 4th International Nonlinear
Microwave Monolithic Integrated Circuit(INMMIC), April 2010, pages:
148 – 151.
[13] T. Williams, J. Benedikt, P. J. Tasker, “Fully Functional Real Time
Non-Linear Device Characterization System Incorporating Active Load
Control”, in Proc. 36th European Microwave Conference (EuMC),
October 2006, pages: 1610-1613.
[14] T. Williams, J. Benedikt, P. J. Tasker, “Experimental evaluation of an
active envelope load pull architecture for high speed device
characterization”, in Proc. IEEE MTT-S Int. Microwave Symp. Dig.,
Long Beach, June 2005, pages: 1509-1512.
[15] M. Akmal, J. Lees, S. Bensmida, S. Woodington, V. Carrubba, S.
Cripps, J. Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker,
“The Effect of Baseband Impedance Termination on the Linearity of
GaN HEMTs”, 40th IEEE European Microwave Conference(EuMC),
September 2010, pages: 1046 -1049.
[16] M. Akmal, J. Lees, V. Carrubba, S. Bensmida, S. Woodington, J.
Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker,
“Minimization of Baseband Electrical Memory Effects in GaN HEMTs
Using IF Active Load-pull”, in Proc. Of IEEE Asia Pacific Microwave
Conference (APMC. December 2010), pages: 5-8.
[17] M. Akmal, V. Carrubba, J. Lees, S. Bensmida, S. Woodington, J.
Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker, “Linearity
Enhancement of GaN HEMTs under Complex Modulated Excitation by
Optimizing the Baseband Impedance Environment”, in Proc. of IEEE
MTT-S International. Microwave Symposium, June 2011, pages(s):1-4.
[18] M. Akmal, J. Lees, , J. Benedikt, P.J. Tasker, Characterization of
electrical memory effects for complex multi-tone excitations using
broadband active baseband load-pull”, in Proc. of 42nd European
Microwave Conference (EuMC), October 2012, pages: 1265 -1268.
[19] Chaudhary, M.A.; Lees, J.; Benedikt, J.; Tasker, P., “Reduction of
baseband electrical memory effects using broadband active baseband
load-pull”, in Proc. of IEEE Internation Wireless Symposium (IWS),
April 2013, pages: 1 - 4.
[20] P. Wright, J. Lees, P. J. Tasker, J. Benedikt, S.C. Cripps, “An efficient,
linear, broadband class-J-mode PA realised using RF waveform
engineering”, in Proc. of IEEE MTT-S International, June 2009, pages:
653 -656.
[21] V. Carrubba, A. L. Clarke, M. Akmal, J. Lees, J. Benedikt, P. J. Tasker,
S. C. Cripps, “On the Extension of the Continuous Class-F Mode Power
Amplifier,” IEEE Trans. Microw, Theory and Tech., vol. 59, March
2011, pp. 1294-1303.
[22] V. Carrubba, J. Lees, J. Benedikt, P. J. Tasker, S. C. Cripps, ”A Novel
Highly Efficient Broadband Continuous Class-F RFPA Delivering 74%
Average Efficiency for an Octave Bandwidth,” Proceeding of the IEEE
MTT-S Dig., June 2011, pages: 1 – 4.
[1] Joel Vuolevi and Timo Rahkonen, Distortion in RF Power Amplifiers,
Norwood, MA: Artech House, 2003.
[2] B. Kenington, High-Linearity RF Amplifier Design, Norwood, MA:
Artech House, 2000.
[3] C. Fan and K. M. Cheng, “Theoretical and experimental study of
amplifier linearization based on harmonic and baseband signal injection
technique,” IEEE Trans. Microwave Theory Tech., vol. 50, pp. 1801–
1806, July 2002.
[4] J. Vuolevi, J. Manninen, T. Rahkonen, “Cancelling the memory effects
in RF power amplifiers”, IEEE International Circuits and Systems
Symposium, 2001, pp. 57–60.
[5] S. C. Cripps, Advanced Techniques in RF Power Amplifier Design,
Norwood, MA, Artech House, 2006.
[6] M. D. LeFevre, D. W. Runton, C. T. Burns, M. K. Mellor, “Digital
Predistortion from an RF Perspective”, 2010 IEEE Topical Symposium
on Power Amplifiers for Wireless Communications, September 2010.
[7] Z. Yusoff, J. Lees, P. J. Tasker, J. Benedikt, S.C. Cripps, “Linearity
Improvement in RF Power Amplifier System Using Integrated Auxiliary
Envelope Tracking System”, in Proc. of IEEE MTT-S International,
June 2011, pages: 1 -4.
[8] A. Alghanim, J. Benedikt, P.J. Tasker, P “A measurement test-set for
characterisation of high power LDMOS transistors including memory
effects” Proceedings of High Frequency Postgraduate Student
Colloquium, 5-6 September 2005 Page(s): 29 – 32. [9] A. Alghanim, J. Lees,T. Williams, J. Benedikt, P.J. Tasker, “Using
active IF load-pull to investigate electrical base-band induced memory
effects in high-power LDMOS transistors,” in Proc. Asia-Pacific
Microwave Conference, 2007, 11-14 Dec. 2007 Page(s):1 - 4.
[10] J. Lees, T. Williams, S. Woodington, P. McGovern, S. Cripps, J.
Benedikt, and J. Tasker, “Demystifying Device related Memory Effects
using Waveform Engineering and Envelope Domain Analysis,”
European Microwave Conf., Oct. 2008, Amsterdam, pp:753-756.
[11] A. Alghanim, J. Lees,T. Williams, J. Benedikt, P.J. Tasker, P “Using
active IF load-pull to investigate electrical base-band induced memory
effects in high-power LDMOS transistors,” Proceedings of Asia-Pacific
Microwave Conference, December 2007, Page(s):1 - 4.
[12] M. Akmal, J. Lees, S. Bensmida, S. Woodington, J. Benedikt, K. Morris,
M. Beach, J. McGeehan, P. J. Tasker, “ The Impact of Baseband
Electrical Memory Effects on the Dynamic Transfer Characteristics of
Microwave Power Transistors”, in Proc. of 4th International Nonlinear
Microwave Monolithic Integrated Circuit(INMMIC), April 2010, pages:
148 – 151.
[13] T. Williams, J. Benedikt, P. J. Tasker, “Fully Functional Real Time
Non-Linear Device Characterization System Incorporating Active Load
Control”, in Proc. 36th European Microwave Conference (EuMC),
October 2006, pages: 1610-1613.
[14] T. Williams, J. Benedikt, P. J. Tasker, “Experimental evaluation of an
active envelope load pull architecture for high speed device
characterization”, in Proc. IEEE MTT-S Int. Microwave Symp. Dig.,
Long Beach, June 2005, pages: 1509-1512.
[15] M. Akmal, J. Lees, S. Bensmida, S. Woodington, V. Carrubba, S.
Cripps, J. Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker,
“The Effect of Baseband Impedance Termination on the Linearity of
GaN HEMTs”, 40th IEEE European Microwave Conference(EuMC),
September 2010, pages: 1046 -1049.
[16] M. Akmal, J. Lees, V. Carrubba, S. Bensmida, S. Woodington, J.
Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker,
“Minimization of Baseband Electrical Memory Effects in GaN HEMTs
Using IF Active Load-pull”, in Proc. Of IEEE Asia Pacific Microwave
Conference (APMC. December 2010), pages: 5-8.
[17] M. Akmal, V. Carrubba, J. Lees, S. Bensmida, S. Woodington, J.
Benedikt, K. Morris, M. Beach, J. McGeehan, P. J. Tasker, “Linearity
Enhancement of GaN HEMTs under Complex Modulated Excitation by
Optimizing the Baseband Impedance Environment”, in Proc. of IEEE
MTT-S International. Microwave Symposium, June 2011, pages(s):1-4.
[18] M. Akmal, J. Lees, , J. Benedikt, P.J. Tasker, Characterization of
electrical memory effects for complex multi-tone excitations using
broadband active baseband load-pull”, in Proc. of 42nd European
Microwave Conference (EuMC), October 2012, pages: 1265 -1268.
[19] Chaudhary, M.A.; Lees, J.; Benedikt, J.; Tasker, P., “Reduction of
baseband electrical memory effects using broadband active baseband
load-pull”, in Proc. of IEEE Internation Wireless Symposium (IWS),
April 2013, pages: 1 - 4.
[20] P. Wright, J. Lees, P. J. Tasker, J. Benedikt, S.C. Cripps, “An efficient,
linear, broadband class-J-mode PA realised using RF waveform
engineering”, in Proc. of IEEE MTT-S International, June 2009, pages:
653 -656.
[21] V. Carrubba, A. L. Clarke, M. Akmal, J. Lees, J. Benedikt, P. J. Tasker,
S. C. Cripps, “On the Extension of the Continuous Class-F Mode Power
Amplifier,” IEEE Trans. Microw, Theory and Tech., vol. 59, March
2011, pp. 1294-1303.
[22] V. Carrubba, J. Lees, J. Benedikt, P. J. Tasker, S. C. Cripps, ”A Novel
Highly Efficient Broadband Continuous Class-F RFPA Delivering 74%
Average Efficiency for an Octave Bandwidth,” Proceeding of the IEEE
MTT-S Dig., June 2011, pages: 1 – 4.
@article{"International Journal of Electrical, Electronic and Communication Sciences:71797", author = "Muhammad Akmal Chaudhary", title = "Broadband Baseband Impedance Control for Linearity Enhancement in Microwave Devices", abstract = "The out-of-band impedance environment is considered
to be of paramount importance in engineering the in-band impedance
environment. Presenting the frequency independent and constant outof-
band impedances across the wide modulation bandwidth is
extremely important for reliable device characterization for future
wireless systems. This paper presents an out-of-band impedance
optimization scheme based on simultaneous engineering of
significant baseband components IF1 (twice the modulation
frequency) and IF2 (four times the modulation frequency) and higher
baseband components such as IF3 (six times the modulation
frequency) and IF4 (eight times the modulation frequency) to
engineer the in-band impedance environment. The investigations
were carried out on a 10W GaN HEMT device driven to deliver a
peak envelope power of approximately 40.5dBm under modulated
excitation. The presentation of frequency independent baseband
impedances to all the significant baseband components whilst
maintaining the optimum termination for fundamental tones as well
as reactive termination for 2nd harmonic under class-J mode of
operation has outlined separate optimum impedances for best
intermodulation (IM) linearity.", keywords = "Active load-pull, baseband, device characterisation,
waveform measurements.", volume = "9", number = "8", pages = "1008-7", }