0.4-5.8 GHz SiGe-MMIC Quadrature Modulator Employing Self Current Controlled Mixer for Cognitive Radio. - Shintaro Shinjo; Fumiki Onoma; Koji Tsutsumi; Noriharu Suematsu; Mitsuhiro Shimozawa; Hiroshi Harada (IEICE Trans. Commun., 2009)

Adaptively Phase-Shift Controlled Self-Injection Locked VCO. - Masaomi Tsuru; Kengo Kawasaki; Koji Tsutsumi; Eiji Taniguchi (IEICE Trans. Electron., 2015)

A Compact RF Frontend Module of Active Phased Array Antenna for High SHF Wideband Massive MIMO in 5G. - Hideyuki Nakamizo; Shintaro Shinjo; Koji Tsutsumi; Satoshi Yamaguchi; Hideharu Yoshioka; Akihiro Okazaki; Akinori Taira; Kenichi Tajima (IEICE Trans. Electron., 2017)

A 15GHz-Band 4-Channel Transmit/Receive RF Core-Chip for High SHF Wide-Band Massive MIMO in 5G. - Koji Tsutsumi; Takaya Maruyama; Wataru Yamamoto; Takanobu Fujiwara; Tatsuya Hagiwara; Ichiro Somada; Eiji Taniguchi; Mitsuhiro Shimozawa (IEICE Trans. Electron., 2017)

A 0.3-to-5.5 GHz Digital Frequency Discriminator IC with Time to Digital Converter and Edge Counter for Instantaneous Frequency Measurement. - Akihito Hirai; Koji Tsutsumi; Hideyuki Nakamizo; Eiji Taniguchi; Kenichi Tajima; Kazutomi Mori; Masaomi Tsuru; Mitsuhiro Shimozawa (IEICE Trans. Electron., 2019)

Variable-Gain Phase Shifter with Phase Compensation Using Varactors. - Akihito Hirai; Yuki Tsukui; Koji Tsutsumi; Kazutomi Mori (IEICE Trans. Electron., 2023)