Patent 無線通信システム 平賀健, 坂元一光, 関智弘, 中川匡夫, 上原一浩 Application no. 特願2013-000502 Date applied Jan 7, 2013 Announcement no. 特開2014-132726 Date announced Nov 6, 2015 Patent/Registration no. 特許5833584 Date registered Nov 6, 2015 Date issued