Publications de Ayfer Özgür Aydin

Advances and Open Problems in Federated Learning

Martin Jaggi, Sebastian Urban Stich, Yang Liu, Lie He, Ayfer Özgür Aydin, Florian Tramèr, Qiang Yang, Ananda Theertha Suresh, Badih Ghazi

Federated learning (FL) is a machine learning setting where many clients (e.g., mobile devices or whole organizations) collaboratively train a model under the orchestration of a central server (e.g., service provider), while keeping the training data decen ...

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On the Complexity of Scheduling in Half-Duplex Diamond Networks

Christina Fragouli, Ayfer Özgür Aydin, Siddhartha Brahma

We consider an n-relay Gaussian diamond network where a source communicates to a destination with the help of n half-duplex relays. Achieving rates close to the capacity of this network requires to employ all the n relays under an optimal transmit/receive ...

Ieee-Inst Electrical Electronics Engineers Inc2016

Simple Relaying Strategies for Half-duplex Networks

Christina Fragouli, Ayfer Özgür Aydin, Siddhartha Brahma

We consider the diamond network where a source communicates with the destination through N non-interfering half-duplex relays. Using simple outer bounds on the capacity of the network, we show that simple relaying strategies having exactly two states and a ...

2012

Network simplification: the Gaussian diamond network with Multiple Antennas

Christina Fragouli, Ayfer Özgür Aydin, Javad Ebrahimi Boroojeni

We consider the N-relay Gaussian diamond network when the source and the destination have ns ≥ 2 and nd ≥ 2 antennas respectively. We show that when ns = nd = 2 and when the individual MISO channels from the source to each relay and the SIMO channels from ...

2011

Throughput-Delay Tradeoff for Hierarchical Cooperation in Ad Hoc Wireless Networks

Olivier Lévêque, Ayfer Özgür Aydin

Hierarchical cooperation has recently been shown to achieve better throughput scaling than classical multihop schemes under certain assumptions on the channel model in static wireless networks. However, the end-to-end delay of this scheme turns out to be s ...

Institute of Electrical and Electronics Engineers2010

Information Theoretic Operating Regimes of Large Wireless Networks

Olivier Lévêque, Ayfer Özgür Aydin

In analyzing the point-to-point wireless channel, insights about two qualitatively different operating regimes --bandwidth- and power-limited-- have proven indispensable in the design of good communication schemes. In this paper, we propose a new scaling l ...

2010

Linear Capacity Scaling in Wireless Networks: Beyond Physical Limits?

Olivier Lévêque, Ayfer Özgür Aydin

We investigate the role of cooperation in wireless networks subject to a spatial degrees of freedom limitation. To address the worst case scenario, we consider a free-space line-of-sight type environment with no scattering and no fading. We identify three ...

2010

Achieving Linear Scaling with Interference Alignment

Ayfer Özgür Aydin

Recent results have shown that interference alignment can achieve K/2 degrees of freedom in a K-user interference channel with time or frequency varying channel coefficients. For fixed number of users K, the number of degrees of freedom characterizes the a ...

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2009

Fundamental limits and optimal operation in large wireless networks

Ayfer Özgür Aydin

Wireless adhoc networks consist of users that want to communicate with each other over a shared wireless medium. The users have transmitting and receiving capabilities but there is no additional infrastructure for assisting communication. This is in contra ...

EPFL2009

Information Theoretic Operating Regimes of Large Wireless Networks

Olivier Lévêque, Ayfer Özgür Aydin

2008