In this paper, the design of a class-F radio frequency power amplifier with a multiharmonic input transmission line network is presented. Harmonic signal components at the gate come from several sources including nonlinear device capacitances and imperfect output harmonic terminations that create harmonic components that are fed back to the gate through the gate-drain capacitance. The effect of these harmonic generation mechanisms and the potential to shape the gate waveform to improve power efficiency are investigated. The study shows that a second harmonic short is most beneficial and the effect of a third harmonic termination is small. The concepts are applied to the design of a 10 W GaN class-F amplifier and the design is supported by theoretical, simulation and experimental results. The fabricated design has a measured drain efficiency of 78.8% at an output power of 40.5 dBm for a frequency of 990 MHz. The amplifier was also tested with a 8.8 dB peak-to-average power ratio 5 MHz WCDMA signal. With the modulated signal, the adjacent channel power ratio was -33.1 dBc at a drain efficiency of 46.1% without predistortion correction.
"Effect of Second and Third Harmonic Input Impedances in a Class-F Amplifier," Progress In Electromagnetics Research C,
Vol. 56, 39-53, 2015. doi:10.2528/PIERC14101410
1. Raab, F. H., "Class-F power amplifiers with maximally flat waveforms," IEEE Trans. Microwave Theory, Vol. 45, No. 11, 2007-2012, 1997. doi:10.1109/22.644215
2. Carrubba, V., A. L. Clarke, M. Akmal, J. Lees, J. Benedikt, P. J. Tasker, and S. C. Cripps, "On the extension of the continuous class-F mode power amplifier," IEEE Trans. Microwave Theory, Vol. 59, No. 5, 1294-1303, 2011. doi:10.1109/TMTT.2011.2117435
3. Chen, K. and D. Peroulis, "A 3.1-GHz class-F power amplifier with 82% power-added-efficiency," Microwave and Wireless Components Letters, Vol. 23, No. 8, 436-438, 2013. doi:10.1109/LMWC.2013.2271295
4. Hwang, T., K. Azadet, R. Wilson, and J. Lin, "Characterization of class-F power amplifier with wide amplitude and phase bandwidth for outphasing architecture," Microwave and Wireless Components Letters, Vol. 24, No. 3, 188-190, 2014. doi:10.1109/LMWC.2013.2292929
5. Kim, J. and Y. Park, "Design of a compact and broadband inverse class-F-1 power amplifier," Progress In Electromagnetics Research C, Vol. 46, 75-81, 2014. doi:10.2528/PIERC13112404
7. Mediano, A. and N. Sokal, "A Class-E RF power amplifier with a flat-top transistor-voltage waveform," IEEE Trans. Power Electronics, Vol. 28, No. 11, 5215-5221, 2013. doi:10.1109/TPEL.2013.2242097
8. Abbasian, S. and T. Johnson, "RF current mode class-D power amplifiers under periodic and non-periodic switching conditions," International Symposium on Circuits and Systems (ISCAS), 610-613, 2013.
9. Moon, J., S. Jee, J. Kim, and B. Kim, "Behaviours of class-F and class-F-1 amplifiers," IEEE Trans. Microwave Theory, Vol. 60, No. 6, 1937-1951, 2012. doi:10.1109/TMTT.2012.2190749
10. Ramadan, A., T. Reveyrand, A. Martin, J. M. Nebus, P. Bouysse, L. Lapierre, J. F. Villemazet, and S. Forestier, "Experimental study on effect of second-harmonic injection at input of classes F and F-1 GaN power amplifiers," Electronics Letters, Vol. 46, No. 8, 570-572, 2010. doi:10.1049/el.2010.0392
11. White, P., "Effect of input harmonic terminations on high efficiency class-B and class-F operation of PHEMT devices," IEEE MTT-S Int. Microwave Symp. Dig., Vol. 3, 1611-1614, 1998.
12. Goto, S., T. Kunii, A. Ohta, A. Inoue, Y. Hosokawa, R. Hattori, and Y. Mitsui, "Effect of bias condition and input harmonic termination on high e±ciency inverse class-F amplifiers," 31st European Microwave Conference (EuMC), 1-4, 2001.
13. Colantonio, P., F. Giannini, G. Leuzzi, and E. Limiti, "Theoretical facet and experimental results of harmonic tuned PAs," Int. J. RF Microw. Comput.-Aided Eng., Vol. 13, No. 6, 459-472, 2003. doi:10.1002/mmce.10106
14. Colantonio, P., F. Giannini, and E. Limiti, "An approach to harmonic load- and source-pull measurements for high-efficiency PA design," IEEE Trans. Microwave Theory, Vol. 52, No. 1, 191-198, 2004. doi:10.1109/TMTT.2003.821276
15. Colantonio, P., F. Giannini, G. Leuzzi, and E. Limiti, "Multiharmonic manipulation for highly efficient microwave power amplifiers," Int. J. RF Microw. Comput.-Aided Eng., Vol. 11, 366-384, 2001. doi:10.1002/mmce.1045
16. Gao, S., P. Butterworth, S. Ooi, and A. Sambell, "High-efficiency power amplifier design including input harmonic termination," IEEE Microwave and Wireless Components Letters, Vol. 16, No. 2, 81-83, 2005. doi:10.1109/LMWC.2005.863171
17. Lovelace, D., J. Costa, and N. Camilleri, "Extracting small-signal model parameters of silicon MOSFET transistors," EEE MTT-S Dig., 865-868, 1994.
18. CGH60015D Datasheet, Rev. 3.1, , Cree, Inc. 2012.
19. Colantonio, P., F. Giannini, and E. Limiti, High Efficiency RF and Microwave Solid State Power Amplifiers, John Wiley & Sons, Inc., 2009. doi:10.1002/9780470746547
20. Woo, Y., Y. Yang, and B. Kim, "Analysis and experiments for high-efficiency Class-F and inverse Class-F power amplifiers," Class-F power amplifiers, Vol. 54, No. 5, 1969-1974, 2006.
21. Vadala, V., A. Raffo, S. Di Falco, G. Bosi, A. Nalli, and G. Vannini, "A load pull characterization technique accounting for harmonic tuning," IEEE Trans. Microwave Theory, Vol. 61, No. 7, 2695-2704, 2013. doi:10.1109/TMTT.2013.2262803
22. Dambrine, G., A. Cappy, F. Heliodore, and E. Playez, "A new method for determining the FET small-signal equivalent circuit," IEEE Trans. Microwave Theory, Vol. 36, No. 7, 1151-1159, 1998. doi:10.1109/22.3650
23. Jarndal, A. and G. Kompa, "A new small-signal modeling approach applied to GaN devices," IEEE Trans. Microwave Theory, Vol. 53, No. 11, 3440-3448, 2005. doi:10.1109/TMTT.2005.857332
24. Colantonio, P., F. Giannini, R. Giofre, and L. Piazzon, "A design technique for concurrent dual band harmonic tuned power amplifier," IEEE Trans. Microwave Theory, Vol. 56, No. 11, 2545-2555, 2008. doi:10.1109/TMTT.2008.2004897
25. Rollett, J., "Stability and power-gain invariants of linear twoports," IEEE Trans. Circuit Theory, Vol. 9, No. 1, 29-32, 1962. doi:10.1109/TCT.1962.1086854
26. Nemati, H., C. Fager, M. Thorsell, and H. Zirath, "High-efficiency LDMOS power-amplifier design at 1 GHz using an optimized transistor model," IEEE Trans. Microwave Theory, Vol. 57, No. 7, 1647-1654, 2009. doi:10.1109/TMTT.2009.2022590
27. Saad, P., C. Fager, H. Nemati, H. Cao, H. Zirath, and K. Andersson, "A highly efficient 3.5 GHz inverse class-F GaN HEMT power amplifier," Int. J. of Microwave and Wireless, Vol. 2, No. 3-4, 317-324, 2010. doi:10.1017/S1759078710000395
28. Saad, P., C. Fager, H. Cao, H. Zirath, and K. Andersson, "Design of a highly efficient 2-4 GHz octave bandwidth GaN-HEMT power amplifier," IEEE Trans. Microwave Theory, Vol. 58, No. 7, 1677-1685, 2010. doi:10.1109/TMTT.2010.2049770
29. Bassam, S. A., M. Helaoui, and F. M. Ghannouchi, "2-D Digital predistortion (2-D-DPD) architecture for concurrent dual-band transmitters," IEEE Trans. Microwave Theory, Vol. 59, No. 10, 2547-2553, 2011. doi:10.1109/TMTT.2011.2163802
30. Yu, X. and H. Jiang, "Digital predistortion using adaptive basis functions," IEEE Trans. Circuits Syst. I, Vol. 60, No. 12, 3317-3327, 2013. doi:10.1109/TCSI.2013.2265958