A High Efficiency Doherty Power Amplifier for TV Band Applications

Mohamad Y. Abou-Shahine^*, Youssef Nasser, Karim Y. Kabalan

Electrical and Computer Engineering Department, American University of Beirut, Beirut, Lebanon.

DOI: 10.4236/jemaa.2015.712031                

Abstract

This paper presents a high efficiency Doherty power amplifier suitable for TV band applications. A class AB power amplifier is firstly implemented using a commercial GaN HEMT from Cree Incorporation, achieving a high power-added-efficiency of 77.78% and a 40.593 dBm output power with an associated gain of 21.65 dB. The Doherty amplifier has then been designed following the previous class AB scheme for the main amplifier and a class C scheme for the peak one. This amplifier attained a high power-added-efficiency of 81.94%, a 42.77 dBm output power, an associated gain of 21.32 dB, and an operating frequency bandwidth between 550 and 1000 MHz (58.06% fractional bandwidth) which made it suitable for TV band applications.

Keywords

Power Amplifier, Class AB, Doherty Power Amplifier, Efficiency, TV Band

Conflicts of Interest

The authors declare no conflicts of interest.

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