A multilevel QAM demodulator VLSI with wideband carrier recovery and dual equalizing mode. - Kazuya Yamanaka; Sumitaka Takeuchi; Shuji Murakami; Masayuki Koyama; Jun Ido; Takashi Fujiwara; Susumu Hirano; Keisuke Okada; Tadashi Sumi (IEEE J. Solid State Circuits, 1997)

High-Speed Multilevel Coded Modulation and Soft Performance Monitoring in Optical Communications. - Tsuyoshi Yoshida; Isamu Kudo; Kenji Ishii; Hideo Yoshida; Hidenori Shimizu; Susumu Hirano; Yoshiaki Konishi; Magnus Karlsson 001; Erik Agrell (OFC, 2024)