Residual Non-Linear Phase Noise in Probabilistically Shaped 64-QAM Optical Links

2018 ◽  
Author(s):  
Dario Pilori ◽  
F. Forghieri ◽  
Gabriella Bosco
Keyword(s):  
Phase Noise ◽  
Linear Phase ◽  
Optical Links ◽  
Non Linear

Non-Linear Phase Noise Mitigation Over Systems Using Constellation Shaping

2019 ◽  
Vol 37 (14) ◽  
pp. 3475-3482 ◽  
Author(s):  
Dario Pilori ◽  
Antonino Nespola ◽  
Fabrizio Forghieri ◽  
Gabriella Bosco
Keyword(s):  
Phase Noise ◽  
Linear Phase ◽  
Noise Mitigation ◽  
Constellation Shaping ◽  
Non Linear

scholarly journals Performance analysis of an all-optical OFDM system in presence of non-linear phase noise

2015 ◽  
Vol 23 (4) ◽  
pp. 3886 ◽  
Author(s):  
Jassim K. Hmood ◽  
Sulaiman W. Harun ◽  
Siamak D. Emami ◽  
Amin Khodaei ◽  
Kamarul A. Noordin ◽  
...  
Keyword(s):  
Performance Analysis ◽  
Phase Noise ◽  
Linear Phase ◽  
Ofdm System ◽  
All Optical ◽  
Non Linear ◽  
Optical Ofdm

scholarly journals Cosmic flows and the expansion of the local Universe from non-linear phase–space reconstructions

2016 ◽  
Vol 456 (4) ◽  
pp. 4247-4255 ◽  
Author(s):  
Steffen Heß ◽  
Francisco-Shu Kitaura
Keyword(s):  
Phase Space ◽  
Cold Dark Matter ◽  
Initial Conditions ◽  
Hubble Constant ◽  
Linear Phase ◽  
Local Universe ◽  
Non Linear ◽  
Galaxy Sample ◽  
Fisher Relation ◽  
The Impact

Abstract In this work, we investigate the impact of cosmic flows and density perturbations on Hubble constant H0 measurements using non-linear phase–space reconstructions of the Local Universe (LU). In particular, we rely on a set of 25 precise constrained N-body simulations based on Bayesian initial conditions reconstructions of the LU using the Two-Micron Redshift Survey galaxy sample within distances of about 90  h−1 Mpc. These have been randomly extended up to volumes enclosing distances of 360  h−1 Mpc with augmented Lagrangian perturbation theory (750 simulations in total), accounting in this way for gravitational mode coupling from larger scales, correcting for periodic boundary effects, and estimating systematics of missing attractors (σlarge = 134  s−1 km). We report on Local Group (LG) speed reconstructions, which for the first time are compatible with those derived from cosmic microwave background-dipole measurements: |vLG| = 685 ± 137  s−1 km. The direction (l, b) = (260$_{.}^{\circ}$5 ± 13$_{.}^{\circ}$3, 39$_{.}^{\circ}$1 ± 10$_{.}^{\circ}$4) is found to be compatible with the observations after considering the variance of large scales. Considering this effect of large scales, our local bulk flow estimations assuming a Λ cold dark matter model are compatible with the most recent estimates based on velocity data derived from the Tully–Fisher relation. We focus on low-redshift supernova measurements out to 0.01 < z < 0.025, which have been found to disagree with probes at larger distances. Our analysis indicates that there are two effects related to cosmic variance contributing to this tension. The first one is caused by the anisotropic distribution of supernovae, which aligns with the velocity dipole and hence induces a systematic boost in H0. The second one is due to the inhomogeneous matter fluctuations in the LU. In particular, a divergent region surrounding the Virgo Supercluster is responsible for an additional positive bias in H0. Taking these effects into account yields a correction of ΔH0 = -1.76 ± 0.21  s− 1 km Mpc− 1, thereby reducing the tension between local probes and more distant probes. Effectively H0 is lower by about 2 per cent.

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