611 citations · 2.4k across the 80 of their papers we have counts for
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Regular Perturbation on the Group-Velocity Dispersion Parameter for Dual-Polarization Short-Reach Systems
Dario Cellini, Vinícius Oliari, Erik Agrell +3
The Manakov equation governs the propagation of signals in dual-polarization systems. Its solution is usually approximated by regular perturbation on the nonlinear Kerr parameter.…
Channel Estimation and LDPC Decoding for Bursty Phase Noise
Han Cui, Frank R. Kschischang, Magnus Karlsson +1
Time-varying distortions in communication systems can significantly degrade the performance of soft-decision forward error correction. This paper presents a burst-aware (BA) low-de…
PIDT: Physics-Informed Digital Twin for Optical Fiber Parameter Estimation
Zicong Jiang, Magnus Karlsson, Erik Agrell +1
We propose physics-informed digital twin (PIDT): a fiber parameter estimation approach that combines a parameterized split-step method with a physics-informed loss. PIDT improves a…
Pilot Distributions for Phase Noise Estimation in Electro-Optic Frequency Comb Systems
Mohammad Farsi, Magnus Karlsson, Erik Agrell
We explore the optimal pilot positioning for phase tracking in electro-optic frequency comb setups. We show that, in contrast to previous results for regular multichannel systems,…
Learning to Extract Distributed Polarization Sensing Data from Noisy Jones Matrices
Mohammad Farsi, Christian Häger, Magnus Karlsson +1
We consider the problem of recovering spatially resolved polarization information from receiver Jones matrices. We introduce a physics-based learning approach, improving noise resi…
Polarization Tracking in the Presence of PDL and Fast Temporal Drift
Mohammad Farsi, Christian Häger, Magnus Karlsson +1
In this paper, we analyze the effectiveness of polarization tracking algorithms in optical transmission systems suffering from fast state of polarization (SOP) rotations and polari…
Frequency Logarithmic Perturbation on the Group-Velocity Dispersion Parameter with Applications to Passive Optical Networks
Vinícius Oliari, Erik Agrell, Gabriele Liga +1
Signal propagation in an optical fiber can be described by the nonlinear Schrödinger equation (NLSE). The NLSE has no known closed-form solution, mostly due to the interaction of d…
Analytical Modeling of Nonlinear Fiber Propagation for Four Dimensional Symmetric Constellations
Hami Rabbani, Mostafa Ayaz, Lotfollah Beygi +4
Coherent optical transmission systems naturally lead to a four dimensional (4D) signal space, i.e., two polarizations each with two quadratures. In this paper we derive an analytic…
Low-Complexity Geometric Shaping
Ali Mirani, Erik Agrell, Magnus Karlsson
Approaching Shannon's capacity via geometric shaping has usually been regarded as challenging due to modulation and demodulation complexity, requiring look-up tables to store the c…
Pilot Distributions for Joint-Channel Carrier-Phase Estimation in Multichannel Optical Communications
Arni F. Alfredsson, Erik Agrell, Magnus Karlsson +1
Joint-channel carrier-phase estimation can improve the performance of multichannel optical communication systems. In the case of pilot-aided estimation, the pilots are distributed…
Optimization of Transmitter-Side Signal Rotations in the Presence of Laser Phase Noise
Arni F. Alfredsson, Erik Agrell, Magnus Karlsson +1
The effects of transmitter-side multidimensional signal rotations on the performance of multichannel optical transmission are studied in the presence of laser phase noise. In parti…
On the Performance under Hard and Soft Bitwise Mismatched-Decoding
Tsuyoshi Yoshida, Mikael Mazur, Jochen Schröder +2
We investigated a suitable auxiliary channel setting and the gap between Q-factors with hard and soft demapping. The system margin definition should be reconsidered for systems emp…
Improved Simulation Accuracy of the Split-Step Fourier Method
Shen Li, Magnus Karlsson, Erik Agrell
We investigate a modified split-step Fourier method (SSFM) by including low-pass filters in the linear steps. This method can simultaneously achieve a higher simulation accuracy an…
End-to-End Learning of Geometrical Shaping Maximizing Generalized Mutual Information
Kadir Gümüs, Alex Alvarado, Bin Chen +2
GMI-based end-to-end learning is shown to be highly nonconvex. We apply gradient descent initialized with Gray-labeled APSK constellations directly to the constellation coordinates…
Performance Monitoring for Live Systems with Soft FEC and Multilevel Modulation
Tsuyoshi Yoshida, Mikael Mazur, Jochen Schröder +2
Performance monitoring is an essential function for margin measurements in live systems. Historically, system budgets have been described by the Q-factor converted from the bit err…
Post-FEC BER Benchmarking for Bit-Interleaved Coded Modulation with Probabilistic Shaping
Tsuyoshi Yoshida, Alex Alvarado, Magnus Karlsson +1
Accurate performance benchmarking after forward error correction (FEC) decoding is essential for system design in optical fiber communications. Generalized mutual information (GMI)…
An Improved Model of Nonlinear Fiber Propagation in the Presence of Kerr Nonlinearity and Stimulated Raman Scattering
Hami Rabbani, Gabriele Liga, Vinicius Oliari +4
Ultra-wideband fiber optical transmission suffers from both Kerr nonlinearity and stimulated Raman scattering (SRS). Mathematical models that address the interplay between Kerr non…
Preferred Design of Hierarchical Distribution Matching
Tsuyoshi Yoshida, Magnus Karlsson, Erik Agrell
Distribution matching and dematching (DM/invDM) are key functions in probabilistic shaping (PS). Recently techniques for low complexity implementation of DM/invDM have been well st…
Pilot-Aided Joint-Channel Carrier-Phase Estimation in Space-Division Multiplexed Multicore Fiber Transmission
Arni F. Alfredsson, Erik Agrell, Henk Wymeersch +4
The performance of pilot-aided joint-channel carrier-phase estimation (CPE) in space-division multiplexed multicore fiber (MCF) transmission with correlated phase noise is studied.…
Hierarchical Distribution Matching for Probabilistically Shaped Coded Modulation
Tsuyoshi Yoshida, Magnus Karlsson, Erik Agrell
The implementation difficulties of combining distribution matching (DM) and dematching (invDM) for probabilistic shaping (PS) with soft-decision forward error correction (FEC) codi…