T. Sakamoto, A. Chiba, and T. Kawanishi, “50-Gb/s 16 QAM by a quad-parallel Mach-Zehnder modulator,” in Proc. ECOC 2007, paper PD2.8, 2007.
H. Yamazaki, T. Yamada, T. Goh, Y. Sakamaki, and A. Kaneko, 64QAM modulator with a hybrid configuration of silica PLCs and LiNbO3 phase modulators for 100-Gb/s applications,” in Proc. ECOC 2009, paper 2.2.1, 2009.
X. Zhou, and J. Yu, “200-Gb/s PDM-16QAM generation using a new synthesizing method,” in Proc. ECOC 2009, paper 10.3.5, 2009.
M. Seimetz, “Transmitter design,” in High-order modulation for optical fiber transmission, (Springer, 2009), pp. 28.
M. Seimetz, “Performance of Coherent Optical Square-16-QAM-Systems Based on IQ-Transmitters and Homodyne Receivers with Digital Phase Estimation,” in Optical Fiber Communication Conference and Exposition and The National Fiber Optic Engineers Conference, Technical Digest (CD) (Optical Society of America, 2006), paper NWA4. http://www.opticsinfobase.org/abstract.cfm?URI=NFOEC-2006-NWA4
A. Sano, H. Masuda, T. Kobayashi, M. Fujiwara, K. Horikoshi, E. Yoshida, Y. Miyamoto, M. Matsui, M. Mizoguchi, H. Yamazaki, Y. Sakamaki, and H. Ishii, “69.1-Tb/s (432 x 171-Gb/s) C- and Extended L-Band Transmission over 240 Km Using PDM-16-QAM Modulation and Digital Coherent Detection,” in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optical Society of America, 2010), paper PDPB7. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2010-PDPB7
Y. K. Huang, E. Ip, M.-F. Huang, B. Zhu, P. N. Ji, Y. Shao, D. W. Peckham, R. Lingle, Y. Aono, T. Tajima, and T. Wang, “10x456-Gb/s DP-16QAM transmission over 8x100 km of ULAF using coherent detection with a 30-GHz Analog-to-Digital Converter,” in Proc. OECC, paper PD3, 2010.
M. Nakazawa, S. Okamoto, T. Omiya, K. Kasai, and M. Yoshida, “256 QAM (64 Gbit/s) Coherent Optical Transmission over 160 km with an Optical Bandwidth of 5.4 GHz,” in Optical Fiber Communication Conference, OSA Technical Digest (CD) (Optical Society of America, 2010), paper OMJ5. http://www.opticsinfobase.org/abstract.cfm?URI=OFC-2010-OMJ5