376 citations · 2.9k across the 110 of their papers we have counts for
21 papers · 1 filter
Shaped Four-Dimensional Modulation Formats for Optical Fiber Communication Systems
Bin Chen, Gabriele Liga, Yi Lei +4
We review the design of multidimensional modulations by maximizing generalized mutual information and compare the maximum transmission reach of recently introduced 4D formats. A mo…
High-Cardinality Hybrid Shaping for 4D Modulation Formats in Optical Communications Optimized via End-to-End Learning
Vinícius Oliari, Boris Karanov, Sebastiaan Goossens +6
In this paper we carry out a joint optimization of probabilistic (PS) and geometric shaping (GS) for four-dimensional (4D) modulation formats in long-haul coherent wavelength divis…
Low-Complexity Geometrical Shaping for 4D Modulation Formats via Amplitude Coding
Bin Chen, Wei Ling, Yunus Can Gültekin +3
Signal shaping is vital to approach Shannon's capacity, yet it is challenging to implement at very high speeds. For example, probabilistic shaping often requires arithmetic coding…
Model-aided Geometrical Shaping of Dual-polarization 4D Formats in the Nonlinear Fiber Channel
Gabriele Liga, Bin Chen, Alex Alvarado
The geometry of dual-polarization four-dimensional constellations is optimized in the optical fiber channel using a recent nonlinear interference model. A 0.27 bit/4D rate gain and…
Capacity Region Bounds for the K user Dispersive Nonlinear Optical WDM Channel with Peak Power Constraints
Viswanathan Ramachandran, Gabriele Liga, Astrid Barreiro +1
It is known that fiber nonlinearities induce crosstalk in a wavelength division multiplexed (WDM) system, which limits the capacity of such systems as the transmitted signal power…
List-encoding CCDM: A Nonlinearity-tolerant Shaper Aided by Energy Dispersion Index
Kaiquan Wu, Gabriele Liga, Alireza Sheikh +3
Recently, a metric called energy dispersion index (EDI) was proposed to indicate the nonlinear interference (NLI) induced by correlated symbols during optical transmission. In this…
On Kurtosis-limited Enumerative Sphere Shaping for Reach Increase in Single-span Systems
Yunus Can Gültekin, Alex Alvarado, Olga Vassilieva +4
The effect of decreasing the kurtosis of channel inputs is investigated for the first time with an algorithmic shaping implementation. No significant gains in decoding performance…
Real-time Transmission of Geometrically-shaped Signals using a Software-defined GPU-based Optical Receiver
Sjoerd van der Heide, Ruben S. Luis, Sebastiaan Goossens +8
A software-defined optical receiver is implemented on an off-the-shelf commercial graphics processing unit (GPU). The receiver provides real-time signal processing functionality to…
Orthogonal Time Frequency Space Modulation: A Discrete Zak Transform Approach
Franz Lampel, Alex Alvarado, Frans M. J. Willems
In orthogonal time frequency space (OTFS) modulation, information-carrying symbols reside in the delay-Doppler (DD) domain. By operating in the DD domain, an appealing property for…
Exponentially-Weighted Energy Dispersion Index for the Nonlinear Interference Analysis of Finite-Blocklength Shaping
Kaiquan Wu, Gabriele Liga, Yunus Can Gültekin +1
A metric called exponentially-weighted energy dispersion index (EEDI) is proposed to explain the blocklength-dependent effective signal-to-noise ratio (SNR) in probabilistically sh…
A Data-driven Optimization of First-order Regular Perturbation Coefficients for Fiber Nonlinearities
Astrid Barreiro, Gabriele Liga, Alex Alvarado
We study the performance of gradient-descent optimization to estimate the coefficients of the discrete-time first-order regular perturbation (FRP). With respect to numerically comp…
On Parameter Optimization and Reach Enhancement for the Improved Soft-Aided Staircase Decoder
Yi Lei, Bin Chen, Gabriele Liga +1
The so-called improved soft-aided bit-marking algorithm was recently proposed for staircase codes (SCCs) in the context of fiber optical communications. This algorithm is known as…
A Capacity Region Outer Bound for the Two-User Perturbative Nonlinear Fiber Optical Channel
Viswanathan Ramachandran, Astrid Barreiro, Gabriele Liga +1
We study a nonlinear fiber optical channel impaired by cross-phase modulation and dispersion from the viewpoint of an interference channel. We characterize an outer bound on the ca…
Kurtosis-limited Sphere Shaping for Nonlinear Interference Noise Reduction in Optical Channels
Yunus Can Gültekin, Alex Alvarado, Olga Vassilieva +4
Nonlinear interference (NLI) generated during the propagation of an optical waveform through the fiber depends on the fourth order standardized moment of the channel input distribu…
Radar Sensing with OTFS: Embracing ISI and ICI to Surpass the Ambiguity Barrier
Musa Furkan Keskin, Henk Wymeersch, Alex Alvarado
Orthogonal time frequency space (OTFS) is a promising alternative to orthogonal frequency division multiplexing (OFDM) in high-mobility beyond 5G communications. In this paper, we…
A Soft-Aided Staircase Decoder Using Three-Level Channel Reliabilities
Yi Lei, Bin Chen, Gabriele Liga +3
The soft-aided bit-marking (SABM) algorithm is based on the idea of marking bits as highly reliable bits (HRBs), highly unreliable bits (HUBs), and uncertain bits to improve the pe…
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…
Temporal Energy Analysis of Symbol Sequences for Fiber Nonlinear Interference Modelling via Energy Dispersion Index
Kaiquan Wu, Gabriele Liga, Alireza Sheikh +2
The stationary statistical properties of independent, identically distributed (i.i.d.) input symbols provide insights on the induced nonlinear interference (NLI) during fiber trans…
Air-to-Ground Directional Channel Sounder With 64-antenna Dual-polarized Cylindrical Array
Jorge Gomez Ponce, Thomas Choi, Naveed A. Abbasi +7
Unmanned Aerial Vehicles (UAVs), popularly called drones, are an important part of future wireless communications, either as user equipment that needs communication with a ground s…
Performance Prediction Recipes for Optical Links
Erik Agrell, Marco Secondini, Alex Alvarado +1
Although forward error-correction (FEC) coding is an essential part of modern fiber-optic communication systems, it is impractical to implement and evaluate FEC in transmission exp…
Modeling of Nonlinear Interference Power for Dual-Polarization 4D Formats
Gabriele Liga, Bin Chen, Astrid Barreiro +1
We assess the accuracy of a recently introduced nonlinear interference model for general dual-polarization 4D formats.~ Unlike previous models for polarization-multiplexed 2D forma…