611 citations · 1.5k across the 35 of their papers we have counts for
12 papers · 1 filter
Capacity Bounds under Imperfect Polarization Tracking
Mohammad Farsi, Magnus Karlsson, Erik Agrell
In optical fiber communication, due to the random variation of the environment, the state of polarization (SOP) fluctuates randomly with time leading to distortion and performance…
Low-complexity Voronoi shaping for the Gaussian channel
S. Li, A. Mirani, M. Karlsson +1
Voronoi constellations (VCs) are finite sets of vectors of a coding lattice enclosed by the translated Voronoi region of a shaping lattice, which is a sublattice of the coding latt…
Compressed Shaping: Concept and FPGA Demonstration
Tsuyoshi Yoshida, Koji Igarashi, Magnus Karlsson +1
Probabilistic shaping (PS) has been widely studied and applied to optical fiber communications. The encoder of PS expends the number of bit slots and controls the probability distr…
Performance Metrics for Systems with Soft-Decision FEC and Probabilistic Shaping
Tsuyoshi Yoshida, Magnus Karlsson, Erik Agrell
High-throughput optical communication systems utilize binary soft-decision forward error correction (SD-FEC) with bit interleaving over the bit channels. The generalized mutual inf…
Modulation Format Independent Joint Polarization and Phase Tracking for Coherent Receivers
Cristian B. Czegledi, Erik Agrell, Magnus Karlsson +1
The state of polarization and the carrier phase drift dynamically during transmission in a random fashion in coherent optical fiber communications. The typical digital signal proce…
Impact of 4D channel distribution on the achievable rates in coherent optical communication experiments
Tobias A. Eriksson, Tobias Fehenberger, Peter A. Andrekson +3
We experimentally investigate mutual information and generalized mutual information for coherent optical transmission systems. The impact of the assumed channel distribution on the…
Influence of Behavioral Models on Multiuser Channel Capacity
Erik Agrell, Magnus Karlsson
In order to characterize the channel capacity of a wavelength channel in a wavelength-division multiplexed (WDM) system, statistical models are needed for the transmitted signals o…
Capacity of a Nonlinear Optical Channel with Finite Memory
Erik Agrell, Alex Alvarado, Giuseppe Durisi +1
The channel capacity of a nonlinear, dispersive fiber-optic link is revisited. To this end, the popular Gaussian noise (GN) model is extended with a parameter to account for the fi…
A Low-Complexity Detector for Memoryless Polarization-Multiplexed Fiber-Optical Channels
Christian Häger, Lotfollah Beygi, Erik Agrell +3
A low-complexity detector is introduced for polarization-multiplexed M-ary phase shift keying modulation in a fiber-optical channel impaired by nonlinear phase noise, generalizing…
Optimizing Constellations for Single-Subcarrier Intensity-Modulated Optical Systems
Johnny Karout, Erik Agrell, Krzysztof Szczerba +1
We optimize modulation formats for the additive white Gaussian noise channel with nonnegative input, also known as the intensity-modulated direct-detection channel, with and withou…
Designing Power-Efficient Modulation Formats for Noncoherent Optical Systems
Johnny Karout, Erik Agrell, Krzysztof Szczerba +1
We optimize modulation formats for the additive white Gaussian noise channel with a nonnegative input constraint, also known as the intensity-modulated direct detection channel, wi…
On the symbol error probability of regular polytopes
Erik Agrell, Magnus Karlsson
An exact expression for the symbol error probability of the four-dimensional 24-cell in Gaussian noise is derived. Corresponding expressions for other regular convex polytopes are…