Ultra-Wideband, Differential-Mode Bandpass Filters with Four Coupled Lines Embedded in Self-Complementary Antennas. - Akira Saitou; Kyoung-Pyo Ahn; Hajime Aoki; Kazuhiko Honjo; Koichi Watanabe (IEICE Trans. Electron., 2007)

Synthesis for Negative Group Delay Circuits Using Distributed and Second-Order RC Circuit Configurations. - Kyoung-Pyo Ahn; Ryo Ishikawa; Akira Saitou; Kazuhiko Honjo (IEICE Trans. Electron., 2009)

UWB Active Balun Design with Small Group Delay Variation and Improved Return Loss. - Kyoung-Pyo Ahn; Ryo Ishikawa; Kazuhiko Honjo (IEICE Trans. Electron., 2011)