Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Principle of algorithms (a) CMA, (b) postfilter (PF), and (c) CMMA. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Simulation setup of 112 Gb/s quadrature duobinary (QDB) spectrum shaping polarization division multiplexed-quadrature phase shift keying (PDM-QPSK) signal with Nyquist and super-Nyquist spectrum efficiency. Optical spectrum of PDM-QPSK before (a) and after (b) optical filter. I/Q mod, I/Q modulator; PBC, polarization beam combiner; n(t), AWGN; EDFA, erbium-doped fiber amplifier; and LO, local oscillator. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Spectrum after the optical filter with different bandwidths. Eye diagrams of 28 GHz (a), 24 GHz (b), and 20 GHz (c) QDB spectrum shaping bandwidth. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Amplitude response of constant modulus algorithm (CMA) and cascaded multimodulus algorithm (CMMA) for super-Nyquist QPSK signal at a 21G/23G/25G optical bandpass filter. (a) Rate of convergence for CMA and (b) rate of convergence for CMMA. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Simulation results of back-to-back bit-error-ratio (BER) performance varying with OSNR for CMA, CMA plus PF, and CMMA. Constellation diagrams for CMA (a), CMA plus PF (b), and CMMA (c) at 21-GHz QDB spectrum shaping. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Simulation results of BER performance varying with QDB spectrum shaping bandwidth with super-Nyquist spectrum efficiency for CMMA. Constellation diagrams for CMMA at 17-GHz (a) and 18-GHz (b) QDB spectrum shaping. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE

Date of download: 5/31/2016 Copyright © 2016 SPIE. All rights reserved. Simulation results of BER performance varying with QDB spectrum shaping bandwidth with super-Nyquist spectrum efficiency for CMA, CMA plus PF, and CMMA in 20-dB (a) and 12-dB (b) OSNR. Figure Legend: From: Characteristics of filtering effect for a polarization division multiplexed-quadrature phase shift keying signal with Nyquist and super-Nyquist spectrum efficiency employing various algorithms Opt. Eng. 2014;53(7): doi: /1.OE