Publications by Erixhen Sula | EPFL Graph Search

Shannon Bounds for Quadratic Rate-Distortion Problems

The Shannon lower bound has been the subject of several important contributions by Berger. This paper surveys Shannon bounds on rate-distortion problems under mean-squared error distortion with a particular emphasis on Berger’s techniques. Moreover, as a n ...

Institute of Electrical and Electronics Engineers (IEEE)2024

Shannon Bounds on Lossy Gray-Wyner Networks

Michael Christoph Gastpar, Erixhen Sula

The Gray-Wyner network subject to a fidelity criterion is studied. Upper and lower bounds for the trade-offs between the private sum-rate and the common rate are obtained for arbitrary sources subject to mean-squared error distortion. The bounds meet exact ...

2022

The Gray-Wyner Network and Wyner's Common Information for Gaussian Sources

Michael Christoph Gastpar, Erixhen Sula

This paper presents explicit solutions for two related non-convex information extremization problems due to Gray and Wyner in the Gaussian case. The first problem is the Gray-Wyner network subject to a sum-rate constraint on the two private links. Here, ou ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2022

Lower bound on relaxed Wyner's Common Information

Michael Christoph Gastpar, Erixhen Sula

An important notion of common information between two random variables is due to Wyner. In this paper, we derive a lower bound on a relaxed variant of Wyner's common information for continuous random variables. The new bound reduces to the lower bound on W ...

IEEE2021

Common Information Components Analysis

Michael Christoph Gastpar, Erixhen Sula

Wyner's common information is a measure that quantifies and assesses the commonality between two random variables. Based on this, we introduce a novel two-step procedure to construct features from data, referred to as Common Information Components Analysis ...

2021

Feedback and Common Information: Bounds and Capacity for Gaussian Networks

Erixhen Sula

Network information theory studies the communication of information in a network and considers its fundamental limits. Motivating from the extensive presence of the networks in the daily life, the thesis studies the fundamental limits of particular network ...

EPFL2021

Optimizing Gain Shaping Filters with Neural Networks for Maximum Cable Capacity under Electrical Power Constraints

Erixhen Sula

We experimentally demonstrate capacity gains of up to 23% under electrical supply power constraints in a long-haul optical fiber cable by optimizing the gain shaping filters using neural networks. ...

IEEE2021

Maximizing Fiber Cable Capacity Under A Supply Power Constraint Using Deep Neural Networks

Erixhen Sula

We experimentally achieve a 19% capacity gain per Watt of electrical supply power in a 12-span link by eliminating gain flattening filters and optimizing launch powers using deep neural networks in a parallel fiber context. (C) 2020 The Authors ...

IEEE2020

Supply-Power-Constrained Cable Capacity Maximization Using Multi-Layer Neural Networks

Erixhen Sula

We experimentally solve the problem of maximizing capacity under a total supply power constraint in a massively parallel submarine cable context, i.e., for a spatially uncoupled system in which fiber Kerr nonlinearity is not a dominant limitation. By using ...

IEEE Institute of Electrical and Electronics Engineers2020

Common Information Components Analysis

Michael Christoph Gastpar, Erixhen Sula

We give an information-theoretic interpretation of Canonical Correlation Analysis (CCA) via (relaxed) Wyner's common information. CCA permits to extract from two high-dimensional data sets low-dimensional descriptions (features) that capture the commonalit ...

IEEE2020

The Gaussian lossy Gray-Wyner network

Michael Christoph Gastpar, Erixhen Sula

We consider the problem of source coding subject to a fidelity criterion for the Gray-Wyner network that connects a single source with two receivers via a common channel and two private channels. The pareto-optimal trade-offs between the sum-rate of the pr ...

2020

Sum-Rate Capacity for Symmetric Gaussian Multiple Access Channels With Feedback

Michael Christoph Gastpar, Erixhen Sula

The feedback sum-rate capacity is established for the symmetric

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-user Gaussian multiple-access channel (GMAC). The main contribution is a converse bound that combines the dependence-balance argument of Hekstra and Willems (1989) with a variant of the f ...

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC2020

Compute–Forward Multiple Access (CFMA): Practical Implementations

Michael Christoph Gastpar, Adriano Pastore, Jingge Zhu, Erixhen Sula, Sung Hoon Lim

We present a practical strategy that aims to attain rate points on the dominant face of the multiple access channel capacity using a standard low complexity decoder. This technique is built upon recent theoretical developments of Zhu and Gastpar on compute ...

2019

Relaxed Wyner's Common Information

Michael Christoph Gastpar, Erixhen Sula

In the problem of coded caching for media delivery, two separate coding opportunities have been identified. The first opportunity is a multi-user advantage and crucially hinges on a public broadcast link in the delivery phase. This has been explored in a p ...

IEEE2019

Sum-Rate Capacity for Symmetric Gaussian Multiple Access Channels with Feedback

Michael Christoph Gastpar, Erixhen Sula

The feedback sum-rate capacity is established for the symmetric three-user Gaussian multiple-access channel (GMAC). The main contribution is a converse bound that combines the dependence-balance argument of Hekstra and Willems (1989) with a variant of the ...

2018

Compute-forward multiple access (CFMA) with nested LDPC codes

Michael Christoph Gastpar, Adriano Pastore, Jingge Zhu, Erixhen Sula, Sung Hoon Lim

Inspired by the compute-and-forward scheme from Nazer and Gastpar, a novel multiple-access scheme introduced by Zhu and Gastpar makes use of nested lattice codes and sequential decoding of linear combinations of codewords to recover the individual messages ...

2017