High power and high efficiency GaN-HEMT for microwave communication applications

This paper describes the developement of high power and high efficiency GaN HEMT amplifiers for base transciever station (BTS) applications. The suitability of the GaN HEMT to the switching mode amplification is confirmed by the result of the Class-E amplifier with more than 80% drain efficiency. The recent achievement of successful improvement of the backed off efficiency by Doherty or envelope tracking operation through the GaN HEMT chip optimization proves the excellent saturated efficiency performance. A series of results including high robustness and high reliability suggest the GaN HEMT is a promising technology for microwave power transmission applications, as well as for microwave communication applications.