Design and Performance of 6-GHz 135-Mb/s Radio System with 64-QAM. - Y. Ito; Toshihiko Ryu; Y. Kitahara; T. Noguchi (ICC (2), 1984)

IF Band Cross Polarization Canceler. - Toshihiko Ryu; Masato Tahara; T. Noguchi (ICC (3), 1984)

A Stepped Square 256QAM for Digital Radio System. - Toshihiko Ryu; Junichi Uchibori; Yasuharu Yoshida (ICC, 1986)

6GHz 140Mbps Digital Radio Repeater with 256QAM Modulation. - Yasuharu Yoshida; Masato Tahara; Toshihiko Ryu (ICC, 1986)