The JATES Technology Management & Innovation Awards honor concretely pursued innovations in Japan that contribute to Japan’s economic growth, social change and improved competitiveness. The award-winning innovation is outlined below.
Launch of High-Voltage and High-Efficiency Gallium Nitride Transistor (GaN HEMT) Intended for Compact and Power-Saving Cellular Base Stations
Since around 2004, high-performance 3G/LTE cellular base stations that would enable high-speed communication had been in demand to cope with sharp increases in the use of cellular phones and to support the development of video streaming and other content services. The remote radio head (RRH) system that featured the placement of base stations close to antennas was proposed for easy installation and low power consumption. However, to implement this system, it was necessary to develop a small unit weighing less than 20 kg and occupying less than 20 L, as doing so was difficult with silicon transistors using conventional technologies.
Sumitomo Electric early on recognized the properties of the new compound material gallium nitride (GaN) and worked on the development of high-power, high-efficiency transistors suitable for RRH base station applications. In 2006, achieving substrate and other quality improvements, the Company successfully mass-produced the world’s first high-quality, high-performance GaN HEMT. Furthermore, in cooperation with other manufacturers, Sumitomo Electric refined peripheral technologies such as power supply units and distortion compensators used in conjunction with GaN HEMTs in order to facilitate customers in newly adopting GaN HEMTs and to boost the use of the transistor. As a consequence, cellular base stations have been downsized to less than 10 kg and 10 L and increasingly installed on steel towers and building roofs, enabling higher data-rate wireless cellular networks and supporting rapid proliferation of smartphones and other devices.