logo EDITE Elie AWWAD
Identité
Elie AWWAD
État académique
Thèse soutenue le 2015-01-15
Sujet: Communications optiques à très haut débit utilisant le codage spatio-temporel
Direction de thèse:
Laboratoire:
Voisinage
Ellipse bleue: doctorant, ellipse jaune: docteur, rectangle vert: permanent, rectangle jaune: HDR. Trait vert: encadrant de thèse, trait bleu: directeur de thèse, pointillé: jury d'évaluation à mi-parcours ou jury de thèse.
Productions scientifiques
oai:hal.archives-ouvertes.fr:hal-00755779
Improving PDL Tolerance of Long-Haul PDM-OFDM Systems Using Polarization-Time Coding
We show that Polarization-Time codes can mitigate PDL impairments in long-haul OFDM systems. Coding gains are maintained in weakly non-linear regime and no extra penalty is added when non-linear effects become severe.
Signal Processing in Photonic Communications 2012 Signal Processing in Photonic Communications 2012conference proceeding 2012-06-17
oai:hal.archives-ouvertes.fr:hal-00868656
Polarization-time coding for PDL mitigation in long-haul PolMux OFDM systems
In this paper, we present a numerical, theoretical and experimental study on the mitigation of Polarization Dependent Loss (PDL) with Polarization-Time (PT) codes in long-haul coherent optical fiber transmissions using Orthogonal Frequency Division Multiplexing (OFDM). First, we review the scheme of a polarization-multiplexed (PolMux) optical transmission and the 2 × 2 MIMO model of the optical channel with PDL. Second, we introduce the Space-Time (ST) codes originally designed for wireless Rayleigh fading channels, and evaluate their performance, as PT codes, in mitigating PDL through numerical simulations. The obtained behaviors and coding gains are different from those observed on the wireless channel. In particular, the Silver code performs better than the Golden code and the coding gains offered by PT codes and forward-error-correction (FEC) codes aggregate. We investigate the numerical results through a theoretical analysis based on the computation of an upper bound of the error probability of the optical channel with PDL. The derived upper bound yields a design criterion for optimal PDL-mitigating codes. Furthermore, a transmission experiment of PDL-mitigation in a 1000km optical fiber link with inline PDL validates the numerical and theoretical findings. The results are shown in terms of Q-factor distributions. The mean Q-factor is improved with PT coding and the variance is also narrowed.
Optics Express ISSN:1094-4087article in peer-reviewed journal 2013-09-20
oai:hal.archives-ouvertes.fr:hal-01053539
Space-Time Codes for Mode-Multiplexed Optical Fiber Transmission Systems
We propose space-time codes to mitigate mode dependent loss in spatial division multiplexed optical transmission systems using multi-mode fibers. The codes can replace or complement mode scrambling used to reduce loss disparities between the modes.
Advanced Photonics for Communication Congress - Signal Processing in Photonic Communications Advanced Photonics for Communication Congress - Signal Processing in Photonic Communicationsconference proceeding 2014-07-16
oai:hal.archives-ouvertes.fr:hal-00991715
Polarization-Time Coded OFDM for PDL Mitigation in Long-Haul Optical Transmission Systems
We experimentally demonstrate the potential of Polarization-Time codes in mitigating PDL in long-haul transmissions. The Silver code exhibits the best performance (2dB Q-penalty reduction at a PDL of 6dB). Moreover, for inline PDL, it improves the mean Q-factor by 0.6dB while significantly narrowing the variance of the corresponding distribution.
European Conference on Optical Communications European Conference on Optical Communicationsconference proceeding 2013-09-30
oai:hal.archives-ouvertes.fr:hal-00991719
Design Criterion of Polarization-Time Codes for Optical Fiber Channels
Coherent detection with Polarization Multiplexing (PolMux) is the most promising technique for future optical fiber transmission systems. However, the optical channel suffers from non-unitary impairments known as Polarization Dependent Loss (PDL). Space-Time coding, originally designed for wireless Rayleigh fading channels, was proven to be capable of mitigating PDL. Coding gains of ST codes were evaluated through simulations and experiments that showed differences in their performance on the optical channel and on the wireless channel. In this paper, we derive an upper bound of the pairwise error probability of an optical channel considering the PDL effect. This upper bound explains the performance of ST codes used to mitigate PDL and yields the design criterion that a code should satisfy in order to completely mitigate PDL.
IEEE International Conference on Communications IEEE International Conference on Communicationsconference proceeding 2013-06-09
Soutenance
Thèse: "Techniques Emergentes de Codage Espace-Temps pour les Systèmes de Communications Optiques"
Soutenance: 2015-01-15