Mitsubishi Electric US, Inc. will present a hands-on mini lab showcasing its high efficiency, wideband GaN Doherty power amplifier in Booth #1827 at the 2017 International Microwave Symposium (IMS).

Mitsubishi Electric Corporation (Information Technology R&D Center and High Frequency and Optical Device Works), along with Mitsubishi Electric Research Laboratories, presented a paper earlier this year at Radio Wireless Week describing this wideband Doherty power amplifier design technique for next generation LTE base stations, using GaN transistor technology. The demonstration at IMS will illustrate the ability to linearize an ultra-wideband signal applied to Mitsubishi Electric’s GaN power amplifier using an advanced predistortion technique provided by NanoSemi, Inc.

The proliferation of smartphones and tablets will require a dramatic increase in the wireless capacity of base stations. To meet this demand, mobile technologies are moving to next-generation LTE, where the wireless capacities are increased by allocating multiple simultaneous frequency bands (carrier aggregation) above 3 GHz. Operating in multiple simultaneous frequency bands usually requires multiple power amplifiers to cover each frequency band, leading to an increase in the size of the base station.

Conventional base station Doherty power amplifier design presents many challenges to simultaneously achieve both high efficiency and low distortion for wideband carrier aggregation. Using NanoSemi's digital predistortion (DPD) technology, Mitsubishi Electric’s wideband Doherty power amplifier can achieve high efficiencies with up to 200 MHz instantaneous bandwidth while maintaining ACLR of −50 dBc. With this breakthrough, base station designers gain the ability to design a single flexible LTE power amplifier capable of many carrier aggregation scenarios, even above 3 GHz.

Doherty Power Amplifier Performance at 3.5 GHz*

Carrier Configuration

Efficiency Output Power ACLR

100 MHz
(5 LTE carriers x 20 MHz)

47.9% +34.0 dBm −50.0 dBc

160 MHz
(8 LTE carriers x 20 MHz)

46.2% +33.9 dBm −50.8 dBc

200 MHz
(4 LTE carriers x 20 MHz)


+34.2 dBm −50.6 dBc

200 MHz
(10 LTE carriers x 20 MHz)

44.4% +33.2 dBm −50.5 dBc

*Data measured at room temperature.  Measurements may vary from board to board.

The IMS will be held June 6-8 at the Hawaii Convention Center, Honolulu, Hawaii. Attendees are invited to stop by the Mitsubishi Electric US booth for more information and to view the latest GaN technology in action. Visit NanoSemi, Inc. (Booth #2030) for additional live demos and details about linearization techniques.

Mitsubishi Electric’s full line-up of GaN devices, with frequencies in L-, S-, C- and Ku-Bands, at output powers ranging from 2 to 100 W, supports a wide variety of communications applications, including cellular, satellite, ground station and point-to-point.