Loading the Third Harmonic: A Linear and Efficient Post-Matching Doherty PA

Among the most exciting parts of the IEEE Microwave Theory and Techniques Society (MTT-S) 2017 International Microwave Symposium (IMS2017) was the "High-Efficiency Power Amplifier" Student Design Competition (SDC) sponsored by Technical Coordinating Committee MTT-5. This competition focuses on RF power amplifiers (PAs) having both high efficiency and linearity. Competitors are required to design, construct, and measure a high-efficiency PA with a specified linearity at a frequency of their choice between 1 and 10 GHz. The winner is determined by a figure of merit (FOM), with other requirements [1] that must also be satisfied:

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

[3]  Christian Musolff,et al.  Linear Doherty PA at 5 GHz , 2015, IEEE Microwave Magazine.

[4]  G. Fischer,et al.  A Linear and Efficient Doherty PA at 3.5 GHz , 2013, IEEE Microwave Magazine.

[5]  Jun Peng,et al.  A Post-Matching Doherty Power Amplifier Employing Low-Order Impedance Inverters for Broadband Applications , 2015, IEEE Transactions on Microwave Theory and Techniques.

[6]  Jangheon Kim,et al.  The Doherty power amplifier , 2006, IEEE Microwave Magazine.

[7]  Franco Giannini,et al.  A Closed-Form Design Technique for Ultra-Wideband Doherty Power Amplifiers , 2014, IEEE Transactions on Microwave Theory and Techniques.