Optical phase-locked loop for coherent transmission over 500km using heterodyne detection with fiber lasers. - Keisuke Kasai; Jumpei Hongo; Masato Yoshida; Masataka Nakazawa (IEICE Electron. Express, 2007)

The use of a Nyquist filter for reducing an optical signal bandwidth in a coherent QAM optical transmission. - Keisuke Kasai; Jumpei Hongo; Hiroki Goto; Masato Yoshida; Masataka Nakazawa (IEICE Electron. Express, 2008)