Mitsubishi Electric US will be showcasing their high-efficiency, wide-band GaN Doherty Amplifier at the International Microwave Symposium (IMS 2017) in Honolulu, Hawaii from 6-8 June. 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 wide-band Doherty power amplifier design technique for next generation LTE base stations using GaN transistor technology. The demonstration at IMS 2017 will further illustrate the superb ability to linearize an ultra-wideband signal applied to Mitsubishi Electric’s GaN power amplifier using an advanced pre-distortion technique provided by NanoSemi.
The proliferation of smartphones and tablets will require a dramatic increase in wireless capacity of base stations. To meet this demand, mobile technologies are moving to next generation LTE in which 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 base stations.
Conventional base station doherty power amplifier designs presents many challenges to simultaneously achieve both high efficiency and low distortion for wide-band carrier aggregation. Using NanoSemi’s digital pre-distortion (DPD) technology, Mitsubishi Electric’s wide-band 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 3.5GHz
| Carrier Configuration |
Efficiency |
Output Power |
ACLR |
| 100 MHz (5 LTE carriers x 20MHz) |
47.9 % |
+34.0 dBm |
-50.0dBc |
| 160 MHz (8 LTE carriers x 20MHz) |
46.2 % |
+33.9 dBm |
-50.8 dBc |
| 200 MHz (4 LTE carriers x 20MHz) |
47.5 % |
+34.2 dBm |
-50.6 dBc |
| 200 MHz (10 LTE carriers x 20MHz) |
44.4 % |
+33.2 dBm |
-50.5 dBc |
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 watts, support a wide variety of end-communications applications, including cellular base station, satellite, ground station and point to point.
IMS 2017 attendees can stop by the Mitsubishi Electric US booth at IMS2017 for more information and to view the latest GaN technology in action. NanoSemi, Inc. will also be at the event showcasing additional live demos and providing details about best in class linearization techniques.
