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R. Nagarajan, D. Lambert, M. Kato, V. Lal, G. Goldfarb, J. Rahn, M. Kuntz, J. Pleumeekers, A. Dentai, H. -S. Tsai, R. Malendevich, M. Missey, K. -T. Wu, H. Sun, J. McNicol, J. Tang, J. Zhang, T. Butrie, A. Nilsson, M. Reffle, F. Kish, and D. Welch, “10 channel, 100Gbit/s per channel, dual polarization, coherent QPSK, monolithic InP receiver photonic integrated circuit,” in Proc. OFC2011, Mar. 2011, Paper OML7.

N. Alic, G. C. Papen, R. E. Saperstein, R. Jiang, C. Marki, Y. Fainman, S. Radic, and P. A. Andrekson, “Experimental demonstration of 10 Gb/s NRZ extended dispersion-limited reach over 600km-SMF link without optical dispersion compensation,” presented in OFC 2006, Anaheim, CA, March 2006, paper OWB7.

J. Li, E. Tipsuwannakul, M. Karlsson, and P. A. Andrekson, “Low-complexity duobinary signaling and detection for sensitivity improvement in Nyquist-WDM coherent system,” presented in OFC 2012, Los Angeles, CA, March 2012, Paper OM3H.2.

I. Lyubomirsky, “Quadrature duobinary modulation for 100G transmission beyond the Nyquist limit,” in Proc. OFC 2010, San Diego, CA, March 2010, Paper OThM4.

K. Horikoshi, T. Kobayashi, S. Yamanaka, E. Yamazaki, A. Sano, E. Yoshida, and Y. Miyamoto, “Spectrum-narrowing tolerant 171-Gbit/s PDM-16QAM transmission over 1,200 km using maximum likelihood sequence estimation,” in Proc. ECOC 2011, Paper We.10.P1.73.

M. Selmi, Y. Jaouën, and P. Ciblat, “Accurate digital frequency offset estimator for coherent PolMux QAM transmission systems,” in Proc. ECOC 2009, Sep. 2009, Paper P3.08.

G. Gavioli, E. Torrengo, G. Bosco, A. Carena, V. Curri, V. Miot, P. Poggiolini, M. Belmonte, F. Forghieri, C. Muzio, S. Piciaccia, A. Brinciotti, A. L. Porta, C. Lezzi, S. Savory, and S. Abrate, “Investigation of the impact of ultra-narrow carrier spacing on the transmission of a 10-carrier 1Tb/s superchannel,” in Proc. OFC 2010, San Diego, CA, March 2010, Paper OThD3.

S. Chandrasekhar, X. Liu, B. Zhu, and D. W. Peckham, “Transmission of a 1.2 Tb/s 24-carrier no-guard-interval coherent OFDM superchannel over 7200-km of ultra-large-area fiber,” presented at the ECOC 2009, Vienna, Austria, Sep. 20–24, 2009, Paper PD2.6.

J. Yu, Z. Dong, X. Xiao, Y. Xia, S. Shi, C. Ge, W. Zhou, N. Chi, and Y. Shao, “Generation of 112 coherent multi-carriers and transmission of 10 Tb/s (112x100Gb/s) single optical OFDM superchannel over 640 km SMF,” in Proc. OFC2011, Mar. 2011, Paper PDPA6.