The Experts below are selected from a list of 6642 Experts worldwide ranked by ideXlab platform
Xingwen Yi - One of the best experts on this subject based on the ideXlab platform.
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enhanced performance of phase conjugated ofdm subcarriers using digital coherent superposition
Photonic Network Communications, 2016Co-Authors: Xingwen Yi, Changwei Tang, Hongyan Zhou, Dengke ZengAbstract:We have recently demonstrated the improved phase noise tolerance in coherent optical OFDM by digital coherent superposition of optical OFDM subcarriers, which are phase-conjugated pairs with Hermitian Symmetry. In this approach, we realized DCS of OFDM subcarriers in single polarization (or channel), denoted as SP-DCS-OFDM. In this paper, we show that another approach is in dual polarizations, or DP-DCS-OFDM. According to the concept of phase-conjugated twin wave, both approaches can also mitigate the fiber nonlinearity to the first order. We prove that both approaches can cancel the inter-carrier interference (ICI) due to phase noise to the second order, and we derive the reduced ICI power to the fourth order using the Wiener phase noise model. In simulation, we show the enhanced tolerance to the laser phase noise and fiber nonlinearity.
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Theoretical calculation on ICI reduction using digital coherent superposition of optical OFDM subcarrier pairs in the presence of laser phase noise
Optics Express, 2014Co-Authors: Xingwen Yi, Bo XuAbstract:Digital coherent superposition (DCS) of optical OFDM subcarrier pairs with Hermitian Symmetry can reduce the inter-carrier-interference (ICI) noise resulted from phase noise. In this paper, we show two different implementations of DCS-OFDM that have the same performance in the presence of laser phase noise. We complete the theoretical calculation on ICI reduction by using the model of pure Wiener phase noise. By Taylor expansion of the ICI, we show that the ICI power is cancelled to the second order by DCS. The fourth order term is further derived out and only decided by the ratio of laser linewidth to OFDM subcarrier symbol rate, which can greatly simplify the system design. Finally, we verify our theoretical calculations in simulations and use the analytical results to predict the system performance. DCS-OFDM is expected to be beneficial to certain optical fiber transmissions.
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Digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry for phase noise mitigation
Optics Express, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Dinesh Sharma, Qi Yang, Chao Li, Zhaohui LiAbstract:Digital coherent superposition (DCS) provides an approach to combat fiber nonlinearities by trading off the spectrum efficiency. In analogy, we extend the concept of DCS to the optical OFDM subcarrier pairs with Hermitian Symmetry to combat the linear and nonlinear phase noise. At the transmitter, we simply use a real-valued OFDM signal to drive a Mach-Zehnder (MZ) intensity modulator biased at the null point and the so-generated OFDM signal is Hermitian in the frequency domain. At receiver, after the conventional OFDM signal processing, we conduct DCS of the optical OFDM subcarrier pairs, which requires only conjugation and summation. We show that the inter-carrier-interference (ICI) due to phase noise can be reduced because of the Hermitain Symmetry. In a simulation, this method improves the tolerance to the laser phase noise. In a nonlinear WDM transmission experiment, this method also achieves better performance under the influence of cross phase modulation (XPM).
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Experimental Demonstration of Digital Coherent Superposition of Optical OFDM Subcarrier Pairs for Mitigation of Linear and Nonlinear Phase Noise
Optical Fiber Communication Conference, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Qi Yang, Chao Li, Zhaohui LiAbstract:We experimentally demonstrate digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry to mitigate phase noise, including laser phase noise and cross-phase modulation in a WDM transmission.
Zhaohui Li - One of the best experts on this subject based on the ideXlab platform.
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Digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry for phase noise mitigation
Optics Express, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Dinesh Sharma, Qi Yang, Chao Li, Zhaohui LiAbstract:Digital coherent superposition (DCS) provides an approach to combat fiber nonlinearities by trading off the spectrum efficiency. In analogy, we extend the concept of DCS to the optical OFDM subcarrier pairs with Hermitian Symmetry to combat the linear and nonlinear phase noise. At the transmitter, we simply use a real-valued OFDM signal to drive a Mach-Zehnder (MZ) intensity modulator biased at the null point and the so-generated OFDM signal is Hermitian in the frequency domain. At receiver, after the conventional OFDM signal processing, we conduct DCS of the optical OFDM subcarrier pairs, which requires only conjugation and summation. We show that the inter-carrier-interference (ICI) due to phase noise can be reduced because of the Hermitain Symmetry. In a simulation, this method improves the tolerance to the laser phase noise. In a nonlinear WDM transmission experiment, this method also achieves better performance under the influence of cross phase modulation (XPM).
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Experimental Demonstration of Digital Coherent Superposition of Optical OFDM Subcarrier Pairs for Mitigation of Linear and Nonlinear Phase Noise
Optical Fiber Communication Conference, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Qi Yang, Chao Li, Zhaohui LiAbstract:We experimentally demonstrate digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry to mitigate phase noise, including laser phase noise and cross-phase modulation in a WDM transmission.
Bo Xu - One of the best experts on this subject based on the ideXlab platform.
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Theoretical calculation on ICI reduction using digital coherent superposition of optical OFDM subcarrier pairs in the presence of laser phase noise
Optics Express, 2014Co-Authors: Xingwen Yi, Bo XuAbstract:Digital coherent superposition (DCS) of optical OFDM subcarrier pairs with Hermitian Symmetry can reduce the inter-carrier-interference (ICI) noise resulted from phase noise. In this paper, we show two different implementations of DCS-OFDM that have the same performance in the presence of laser phase noise. We complete the theoretical calculation on ICI reduction by using the model of pure Wiener phase noise. By Taylor expansion of the ICI, we show that the ICI power is cancelled to the second order by DCS. The fourth order term is further derived out and only decided by the ratio of laser linewidth to OFDM subcarrier symbol rate, which can greatly simplify the system design. Finally, we verify our theoretical calculations in simulations and use the analytical results to predict the system performance. DCS-OFDM is expected to be beneficial to certain optical fiber transmissions.
Qi Yang - One of the best experts on this subject based on the ideXlab platform.
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Digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry for phase noise mitigation
Optics Express, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Dinesh Sharma, Qi Yang, Chao Li, Zhaohui LiAbstract:Digital coherent superposition (DCS) provides an approach to combat fiber nonlinearities by trading off the spectrum efficiency. In analogy, we extend the concept of DCS to the optical OFDM subcarrier pairs with Hermitian Symmetry to combat the linear and nonlinear phase noise. At the transmitter, we simply use a real-valued OFDM signal to drive a Mach-Zehnder (MZ) intensity modulator biased at the null point and the so-generated OFDM signal is Hermitian in the frequency domain. At receiver, after the conventional OFDM signal processing, we conduct DCS of the optical OFDM subcarrier pairs, which requires only conjugation and summation. We show that the inter-carrier-interference (ICI) due to phase noise can be reduced because of the Hermitain Symmetry. In a simulation, this method improves the tolerance to the laser phase noise. In a nonlinear WDM transmission experiment, this method also achieves better performance under the influence of cross phase modulation (XPM).
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Experimental Demonstration of Digital Coherent Superposition of Optical OFDM Subcarrier Pairs for Mitigation of Linear and Nonlinear Phase Noise
Optical Fiber Communication Conference, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Qi Yang, Chao Li, Zhaohui LiAbstract:We experimentally demonstrate digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry to mitigate phase noise, including laser phase noise and cross-phase modulation in a WDM transmission.
Chao Li - One of the best experts on this subject based on the ideXlab platform.
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Digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry for phase noise mitigation
Optics Express, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Dinesh Sharma, Qi Yang, Chao Li, Zhaohui LiAbstract:Digital coherent superposition (DCS) provides an approach to combat fiber nonlinearities by trading off the spectrum efficiency. In analogy, we extend the concept of DCS to the optical OFDM subcarrier pairs with Hermitian Symmetry to combat the linear and nonlinear phase noise. At the transmitter, we simply use a real-valued OFDM signal to drive a Mach-Zehnder (MZ) intensity modulator biased at the null point and the so-generated OFDM signal is Hermitian in the frequency domain. At receiver, after the conventional OFDM signal processing, we conduct DCS of the optical OFDM subcarrier pairs, which requires only conjugation and summation. We show that the inter-carrier-interference (ICI) due to phase noise can be reduced because of the Hermitain Symmetry. In a simulation, this method improves the tolerance to the laser phase noise. In a nonlinear WDM transmission experiment, this method also achieves better performance under the influence of cross phase modulation (XPM).
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Experimental Demonstration of Digital Coherent Superposition of Optical OFDM Subcarrier Pairs for Mitigation of Linear and Nonlinear Phase Noise
Optical Fiber Communication Conference, 2014Co-Authors: Xingwen Yi, Xuemei Chen, Qi Yang, Chao Li, Zhaohui LiAbstract:We experimentally demonstrate digital coherent superposition of optical OFDM subcarrier pairs with Hermitian Symmetry to mitigate phase noise, including laser phase noise and cross-phase modulation in a WDM transmission.