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mitigation of 40-Gbit/s polarization-multiplexed QPSK by digital processing
in a coherent receiver," J. Lightw. Technol. 26, 36-42 (2008).

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phase-shift keying signals with carrier phase estimation," J. Lightw. Technol. 24, 12-21 (2006).

G. Colavolpe, "Robust multilevel coherent
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J. Armstrong, "OFDM for optical communications," J. Lightw. Technol. 27, 189-204 (2009).

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system," Opt. Exp. 16, 873-879 (2008).

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