Ziad A. El-Sahn

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We experimentally demonstrate the performance of a 10 Gb/s subcarrier multiplexed (SCM) wavelength-division multiplexed (WDM) passive optical network (PON) using 2.5 Gbaud 16-QAM transmission signals. Digital signal processing (DSP) and square-root raised cosine (SRRC) pulse shaping enable both the uplink and downlink channels to achieve net spectral(More)
We experimentally demonstrate the impact of equalization-enhanced phase noise (EEPN) on the performance of 56 Gbaud dual-polarization (DP) QPSK long haul transmission systems. Although EEPN adds additional noise to the received symbols, we show that this reduces the phase variance introduced by the LO laser, and therefore should be considered when designing(More)
—An innovative overlapped-subcarrier multiplexing (O-SCM) technique is proposed for single-feeder wavelength-division multiplexed (WDM) passive optical networks (PONs). Allowing a certain amount of spectral overlap between the uplink and the downlink maximizes the spectrum usage of bandwidth-limited reflective semiconductor optical amplifier (RSOA)-based(More)
Layered pulse amplitude modulation with discrete multitone (PAM-DMT) is proposed to improve the system spectral efficiency of existing passive optical networks (PONs) by modulating both the real and imaginary parts of the subcarriers through different layers. Signals from different layers are then combined for simultaneous transmission. At the receiver, an(More)
Coherent optical interleave-division multiple-access (OIDMA) has been recently proposed for next generation passive optical network (NG-PON) systems. In this paper we present a performance evaluation and comparison of coherent OIDMA and coherent optical code-division multiple-access (OCDMA) PONs in terms of ONU launch power, PON reach, bit error rate (BER),(More)
We derive a closed-form formula for the nonlinear interference in few-mode fibers (FMFs) in strong coupling regime. We also formulate an expression for the nonlinear FMFs capacity. This is carried out by extending the Gaussian noise model (GN-model), that has been used with single-mode fibers (SMFs), to FMFs. We inspect the derived formulas over a(More)
—A queuing subsystem is proposed to the round robin receiver/transmitter (R 3 T) optical code-division multiple-access (OCDMA) protocol. The corresponding state diagram and its mathematical model are outlined. We prove that significant improvement in terms of system throughput and blocking probability can be achieved by only adding a single buffer at each(More)