PON Downstream Scheme Supporting Simultaneously Different ONU Categories

We propose a PON downstream scheme simultaneously supporting different categories of ONUs (e.g. different generations), whereby lower-category ONUs employ components with limited bandwidth. Our solution relies upon CDM utilizing Hadamard codes and the spectral properties of its code words. We propose a novel code allocation scheme and provide two optimization approaches by employing an optimized secondary spreading code and a power allocation scheme to improve the system performance

Deep Neural Network Equalization for Optical Short Reach Communication

Nonlinear distortion has always been a challenge for optical communication due to the nonlinear transfer characteristics of the fiber itself. The next frontier for optical communication is a second type of nonlinearities, which results from optical and electrical components. They become the dominant nonlinearity for shorter reaches. The highest data rates cannot be achieved without effective compensation. A classical countermeasure is receiver-side equalization of nonlinear impairments and memory effects using Volterra series. However, such Volterra equalizers are architecturally complex and their parametrization can be numerical unstable. This contribution proposes an alternative nonlinear equalizer architecture based on machine learning. Its performance is evaluated experimentally on coherent 88 Gbaud dual polarization 16QAM 600 Gb/s back-to-back measurements. The proposed equalizers outperform Volterra and memory polynomial Volterra equalizers up to 6th orders at a target bit-error rate (BER) of 10 −2 by 0.5 dB and 0.8 dB in optical signal-to-noise ratio (OSNR), respectively

Mode-division-multiplexed 3x112-Gb/s DP-QPSK transmission over 80 km few-mode fiber with inline MM-EDFA and blind DSP

We show transmission of a 3x112-Gb/s DP-QPSK mode-division-multiplexed signal up to 80km, with and without multi-mode EDFA, using blind 6x6 MIMO digital signal processing. We show that the OSNR-penalty induced by mode-mixing in the multi-mode EDFA is negligible

200Gb/s VCSEL transmission using 60m OM4 MMF and KP4 FEC for AI computing clusters

We show a beyond 200Gb/s VCSEL transmission experiment. Results are based on 35GHz VCSEL and advanced DSP. We show an AIR of 245Gb/s PAM-6 back-to-back, and 200Gb/s PAM-4 over 60m OM4 fiber assuming KP4-FEC

Photonic Chiplet Interconnection via 3D-Nanoprinted Interposer

Photonic integrated circuits utilize various waveguide materials, each excelling in specific metrics like efficient light emission, low propagation loss, high electro-optic efficiency, and potential for mass production. Inherent shortcomings in each platform push exploration of hybrid and heterogeneous integration, which demands specialized designs and extra fabrication processes for each material combination. Our work introduces a novel hybrid integration scheme employing a 3D-nanoprinted interposer for a photonic chiplet interconnection system. This method represents a generic solution that can readily couple between chips of any material system, with each fabricated on its own technology platform with no change in the established process flow for the individual chips. Mode-size engineering is enhanced by the off-chip parabolic micro-reflectors. The 3D-nanoprinted chip-coupling frame and fiber-guiding funnel enable low-loss, fully passive assembly with a fast-printing process achieving sub-micron accuracy. Mode-field-dimension conversion ratio of 5:2 from fiber to chip is demonstrated with <0.5dB excess loss on top of the 1.7dB inherent coupling loss, marking the largest mode size conversion using non-waveguided components. Additionally, our system demonstrates a 2.5dB die-to-die coupling loss between silicon and InP chips over a 140nm wavelength range (1480nm to 1620nm), showcasing the potential for extensive cross-platform integration by bridging different waveguide materials

Analysis of back-propagation and RF pilot-tone based nonlinearity compensation for a 9x224Gb/s POLMUX-16QAM system

We investigate the joint implementation of back-propagation and RF-pilot tone for fiber nonlinear compensation in POLMUX-16QAM and show that the nonlinear tolerance is drastically improved when compared to OFDM systemPeer ReviewedPostprint (published version