Shigeo Kawasaki Yuta Kobayashi Satoshi Yoshida High-power, high-efficiency microwave circuits and modules for wireless power transfer based on green-Eco technology. 28-30 2013 RWS https://doi.org/10.1109/RWS.2013.6486630 conf/rws/2013 db/conf/rws/rws2013.html#KawasakiKY13