Class-E power amplifier optimization for operation above maximum frequency

The optimized Class-E power amplifier (PA) for operation above the maximum frequency is described. We have found that the performance of the Class-E PA above the maximum frequency can be enhanced by the bifurcated current through saturation. The performance of the Class-E PA can be further improved by the inductive second harmonic tuning and power matched fundamental load. The resulting saturated amplifier delivers higher output power and efficiency because of the tuned load and the proper second harmonic voltage component generated by the second harmonic load matching. A highly efficient saturated amplifier is designed using Cree GaN HEMT CGH40010 device at 3.5 GHz. It provides a drain efficiency of 75.8% at a saturated power of 40.2 dBm (10.5W).

[1]  Bumman Kim,et al.  Investigation of a Class-J Power Amplifier With a Nonlinear $C_{\rm out}$ for Optimized Operation , 2010, IEEE Transactions on Microwave Theory and Techniques.

[2]  F. Raab.  Class-F power amplifiers with maximally flat waveforms , 1997 .

[3]  No Sokal,et al.  CLASS-E - NEW CLASS OF HIGH-EFFICIENCY TUNED SINGLE-ENDED SWITCHING POWER AMPLIFIERS , 1975 .

[4]  J. Lees,et al.  A Methodology for Realizing High Efficiency Class-J in a Linear and Broadband PA , 2009, IEEE Transactions on Microwave Theory and Techniques.

[5]  J. Lees,et al.  On the Continuity of High Efficiency Modes in Linear RF Power Amplifiers , 2009, IEEE Microwave and Wireless Components Letters.

[6]  Franco Giannini,et al.  High efficiency low-voltage power amplifier design by second-harmonic manipulation , 2000 .

[7]  S. C. Cripps,et al.  RF Power Amplifiers for Wireless Communications , 1999 .

[8]  Bumman Kim,et al.  Analysis and experiments for high-efficiency class-F and inverse class-F power amplifiers , 2006 .

[9]  Jangheon Kim,et al.  Saturated Power Amplifier Optimized for Efficiency Using Self-Generated Harmonic Current and Voltage , 2011, IEEE Transactions on Microwave Theory and Techniques.

[10]  Zoya Popovic,et al.  Switched-mode high-efficiency microwave power amplifiers in a free-space power-combiner array , 1998 .

[11]  S. Gao,et al.  High efficiency class-F RF/microwave power amplifiers , 2006, IEEE Microwave Magazine.

[12]  Franco Giannini,et al.  Theory and experimental validation of a Class E PA above theoretical maximum frequency , 2009, International Journal of Microwave and Wireless Technologies.

[13]  Frederick H. Raab,et al.  Idealized operation of the class E tuned power amplifier , 1977 .

[14]  Franco Giannini,et al.  Class G approach for low‐voltage, high‐efficiency PA design , 2000 .