S. Zhang, X. Li, P. Y. Kam, C. Yu, J. Chen, "Pilot-assisted, decision-aided, maximum likelihood phase estimation in
coherent optical phase-modulated systems with nonlinear phase noise," IEEE Photon. Technol. Lett. 22, 380-382 (2010).

Y. Li, P. Y. Kam, C. C. Chui, "Sequence detection for MPSK/MQAM with adaptive phase tracking," Phys. Commun. 01.003, (2009).

Y. Atzmon, M. Nazarathy, "Laser phase noise in coherent and differential optical transmission
revisited in the polar domain," J. Lightw. Technol. 27, 19-29 (2009).

Y. Atzmon, M. Nazarathy, "A gaussian polar model for error rates of differential phase detection
impaired by linear, non-linear and laser phase noises," J. Lightw. Technol. 27, 4650-4659 (2009).

S. Zhang, P. Y. Kam, C. Yu, J. Chen, "Laser linewidth tolerance of decision-aided maximum likelihood phase
estimation in coherent optical $M$-ary PSK and QAM systems," IEEE Photon. Technol. Lett. 21, 1075-1077 (2009).

S. Zhang, P. Y. Kam, J. Chen, C. Yu, "Decision-aided maximum likelihood detection in coherent optical
phase-shift-keying system," Opt. Exp. 17, 703-715 (2009).

Y. Mori, C. Zhang, K. Igarashi, K. Katoh, K. Kikuchi, "Unrepeated 200-km transmission of 40-Gbit/s 16-QAM signals using digital
coherent receiver," Opt. Exp. 17, 1435-1441 (2009).

W. Shieh, K.-P. Ho, "Equalization-enhanced phase noise for coherent detection systems using
electronic digital signal processing," Opt. Exp. 16, 15718-15727 (2008).

M. Nazarathy, X. Liu, L. Christen, Y. Lize, A. Willner, "Self-coherent optical detection of multi-symbol differential
phase-shift-keyed transmission," J. Lightw. Technol. 26, 1921-1934 (2008).

X. Liu, S. Chandrasekhar, A. Leven, "Digital self-coherent detection," Opt. Exp. 16, 792-803 (2008).

M. Nazarathy, X. Liu, L. Christen, Y. Lize, A. Willner, "Self-coherent decision-feedback-directed 40 Gbps DQPSK receiver," IEEE Photon. Technol. Lett. 19, 828-839 (2007).

Y. K. Lizé, "Tolerances and receiver sensitivity penalties of multi-bit delay
differential phase shift keying demodulation," IEEE Photon. Technol. Lett. 19, 1874-1876 (2007).

E. Ip, J. M. Kahn, "Feedforward carrier recovery for coherent optical communications," J. Lightw. Technol. 25, 2675-2692 (2007).

E. Ip, J. M. Kahn, "Digital equalization of chromatic dispersion and polarization mode
dispersion," J. Lightw. Technol. 25, 2033-2043 (2007).

S. J. Savory, G. Gavioli, R. I. Killey, P. Bayvel, "Transmission of 42.8 Gbit/s polarization multiplexed NRZ-QPSK over 6400 km
of standard fiber with no optical dispersion compensation," Proc. OFC Paper OTuA1 (2007).

T. Pfau, S. Hoffmann, R. Peveling, S. Bhandare, S. K. Ibrahim, O. Adamczyk, M. Porrmann, R. Noe, Y. Achiam, "First real-time data recovery for synchronous QPSK transmission with
standard DFB lasers," IEEE Photon. Technol. Lett. 18, 1907-1909 (2006).

D.-S. Ly-Gagnon, S. Tsukamoto, K. Katoh, K. Kikuchi, "Coherent detection of optical quadrature phase-shift keying signals with
carrier phase estimation," J. Lightw. Technol. 24, 12-21 (2006).

G. Goldfarb, G. Li, "BER estimation of QPSK homodyne detection with carrier phase estimation
using digital signal processing," Opt. Exp. 14, 8043-8053 (2006).

R. No'e, "PLL-free synchronous QPSK polarization multiplex/diversity receiver concept
with digital I&Q baseband processing," IEEE Photon. Technol. Lett. 17, 887-889 (2005).

A. H. Gnauck, P. J. Winzer, "Optical phase-shift-keyed transmission," J. Lightw. Technol. 23, 115-130 (2005).

C. Xu, X. Liu, X. Wei, "Differential phase-shift keying for high spectral efficiency optical
transmissions," IEEE J. Sel. Top. Quantum Electron. 10, 281-293 (2004).

F. Rice, M. Rice, B. Cowley, "A new algorithm for 16 QAM carrier phase estimation using QPSK partitioning," Digital Signal Process. 12, 77-86 (2002).

P. Y. Kam, Y. K. Some, "Approximate bit error probability analysis of 2 PSK and 4 PSK with
partially coherent, symbol-by-symbol detection in carrier phase noise," Proc. Inst. Elect. Eng.—Commun. 146, 120-126 (1999).

P. Y. Kam, K. H. Chua, X. Yu, "Adaptive symbol-by-symbol reception of MPSK on the Gaussian channel with
unknown carrier phase characteristics," IEEE Trans. Commun. 46, 1275-1279 (1998).

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and additive noise," J. Lightw. Technol. 13, 1847-1852 (1995).

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digital data modulations," IEEE Trans. Commun. COM-34, 522-527 (1986).

A. J. Viterbi, A. N. Viterbi, "Nonlinear estimation of PSK-modulated carrier phase with application to
burst digital transmission," IEEE Trans. Inf. Theory IT-29, 543-551 (1983).

W. J. Weber, "Differential encoding for multiple amplitude and phase shift keying systems," IEEE Trans. Commun. COM-26, 385-391 (1978).

F. Rice, M. Rice, B. Cowley, "A new algorithm for 16 QAM carrier phase estimation using QPSK partitioning," Digital Signal Process. 12, 77-86 (2002).

C. Xu, X. Liu, X. Wei, "Differential phase-shift keying for high spectral efficiency optical
transmissions," IEEE J. Sel. Top. Quantum Electron. 10, 281-293 (2004).

R. No'e, "PLL-free synchronous QPSK polarization multiplex/diversity receiver concept
with digital I&Q baseband processing," IEEE Photon. Technol. Lett. 17, 887-889 (2005).

T. Pfau, S. Hoffmann, R. Peveling, S. Bhandare, S. K. Ibrahim, O. Adamczyk, M. Porrmann, R. Noe, Y. Achiam, "First real-time data recovery for synchronous QPSK transmission with
standard DFB lasers," IEEE Photon. Technol. Lett. 18, 1907-1909 (2006).

S. Zhang, P. Y. Kam, C. Yu, J. Chen, "Laser linewidth tolerance of decision-aided maximum likelihood phase
estimation in coherent optical $M$-ary PSK and QAM systems," IEEE Photon. Technol. Lett. 21, 1075-1077 (2009).

Y. K. Lizé, "Tolerances and receiver sensitivity penalties of multi-bit delay
differential phase shift keying demodulation," IEEE Photon. Technol. Lett. 19, 1874-1876 (2007).

S. Zhang, X. Li, P. Y. Kam, C. Yu, J. Chen, "Pilot-assisted, decision-aided, maximum likelihood phase estimation in
coherent optical phase-modulated systems with nonlinear phase noise," IEEE Photon. Technol. Lett. 22, 380-382 (2010).

M. Nazarathy, X. Liu, L. Christen, Y. Lize, A. Willner, "Self-coherent decision-feedback-directed 40 Gbps DQPSK receiver," IEEE Photon. Technol. Lett. 19, 828-839 (2007).

P. Y. Kam, K. H. Chua, X. Yu, "Adaptive symbol-by-symbol reception of MPSK on the Gaussian channel with
unknown carrier phase characteristics," IEEE Trans. Commun. 46, 1275-1279 (1998).

W. J. Weber, "Differential encoding for multiple amplitude and phase shift keying systems," IEEE Trans. Commun. COM-26, 385-391 (1978).

P. Y. Kam, "Maximum-likelihood carrier phase recovery for linear suppressed-carrier
digital data modulations," IEEE Trans. Commun. COM-34, 522-527 (1986).

A. J. Viterbi, A. N. Viterbi, "Nonlinear estimation of PSK-modulated carrier phase with application to
burst digital transmission," IEEE Trans. Inf. Theory IT-29, 543-551 (1983).

D.-S. Ly-Gagnon, S. Tsukamoto, K. Katoh, K. Kikuchi, "Coherent detection of optical quadrature phase-shift keying signals with
carrier phase estimation," J. Lightw. Technol. 24, 12-21 (2006).

E. Ip, J. M. Kahn, "Digital equalization of chromatic dispersion and polarization mode
dispersion," J. Lightw. Technol. 25, 2033-2043 (2007).

A. H. Gnauck, P. J. Winzer, "Optical phase-shift-keyed transmission," J. Lightw. Technol. 23, 115-130 (2005).

E. Ip, J. M. Kahn, "Feedforward carrier recovery for coherent optical communications," J. Lightw. Technol. 25, 2675-2692 (2007).

Y. Atzmon, M. Nazarathy, "Laser phase noise in coherent and differential optical transmission
revisited in the polar domain," J. Lightw. Technol. 27, 19-29 (2009).

C. P. Kaiser, M. Shafi, P. J. Smith, "Analysis methods for optical heterodyne DPSK receivers corrupted by laser
phase noise," J. Lightw. Technol. 11, 1820-1830 (1993).

G. Einarsson, J. Strandberg, I. T. Monroy, "Error probability evaluation of optical systems disturbed by phase noise
and additive noise," J. Lightw. Technol. 13, 1847-1852 (1995).

M. Nazarathy, X. Liu, L. Christen, Y. Lize, A. Willner, "Self-coherent optical detection of multi-symbol differential
phase-shift-keyed transmission," J. Lightw. Technol. 26, 1921-1934 (2008).

Y. Atzmon, M. Nazarathy, "A gaussian polar model for error rates of differential phase detection
impaired by linear, non-linear and laser phase noises," J. Lightw. Technol. 27, 4650-4659 (2009).

G. Goldfarb, G. Li, "BER estimation of QPSK homodyne detection with carrier phase estimation
using digital signal processing," Opt. Exp. 14, 8043-8053 (2006).

X. Liu, S. Chandrasekhar, A. Leven, "Digital self-coherent detection," Opt. Exp. 16, 792-803 (2008).

S. Zhang, P. Y. Kam, J. Chen, C. Yu, "Decision-aided maximum likelihood detection in coherent optical
phase-shift-keying system," Opt. Exp. 17, 703-715 (2009).

Y. Mori, C. Zhang, K. Igarashi, K. Katoh, K. Kikuchi, "Unrepeated 200-km transmission of 40-Gbit/s 16-QAM signals using digital
coherent receiver," Opt. Exp. 17, 1435-1441 (2009).

W. Shieh, K.-P. Ho, "Equalization-enhanced phase noise for coherent detection systems using
electronic digital signal processing," Opt. Exp. 16, 15718-15727 (2008).

Y. Li, P. Y. Kam, C. C. Chui, "Sequence detection for MPSK/MQAM with adaptive phase tracking," Phys. Commun. 01.003, (2009).

P. Y. Kam, Y. K. Some, "Approximate bit error probability analysis of 2 PSK and 4 PSK with
partially coherent, symbol-by-symbol detection in carrier phase noise," Proc. Inst. Elect. Eng.—Commun. 146, 120-126 (1999).

S. J. Savory, G. Gavioli, R. I. Killey, P. Bayvel, "Transmission of 42.8 Gbit/s polarization multiplexed NRZ-QPSK over 6400 km
of standard fiber with no optical dispersion compensation," Proc. OFC Paper OTuA1 (2007).

K.-P. Ho, Phase-Modulated Optical Communication Systems (Springer, 2005).

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H. Louchet, K. Kuzmin, A. Richter, "Improved DSP algorithms for coherent 16- QAM transmission," Proc. ECOC (2008).

M. G. Taylor, "Accurate digital phase estimation for coherent detection using a parallel
digital processor," Proc. ECOC (2005) pp. 263-264.

L. M. Pessoa, H. M. Salgado, I. Darwazeh, "Joint mitigation of optical impairments and phase estimation in coherent
optical systems," Proc. IEEE LEOS Summer Topical Meetings (2008) pp. 169-170.

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A. Atzmon, M. Nazarathy, "Self-coherent differential transmission with decision
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