RAGALEUX Alexandre

PhD graduated
Team : NPA
Departure date : 09/22/2016

Supervision : Anne FLADENMULLER

Co-supervision : BAEY SĂ©bastien

Multiple Access Mechanisms in Broadband Wireless Networks

In this thesis, we study the resource allocation problem within the framework of 4G LTE networks. The OFDMA access method divides the radio resources both in the frequency and time domains. Due to channel impairments, users do not always have the same transmit/receive rates on each resource. In this context, our problem is to share the radio resources between users and enable them to transmit/receive data. The algorithm used to allocate resources is of fundamental importance on system performance.
The LTE standard adds constraints to this problem and makes harder the exploitation of the frequency and the multi-user diversity. Indeed, under these constraints, we show that the resource allocation problem becomes part of the "most difficult" problems. Therefore, the conventional algorithms are often not adapted to a real LTE network.
We provide resource allocation algorithms for both the uplink and downlink of LTE. The constraints of the standard are rigorously taken into account in order to build effective solutions. In addition, the proposed algorithms are generic and can adapt to a wide variety of objectives. In particular, we focus on the support of multimedia traffic with heterogeneous quality of service requirements (bit error rate, delay, jitter, etc.). Indeed, the gradual increase of the offered throughput and the strong popularity of smart mobile devices lead to a massive use of multimedia applications.
Our algorithms are validated through extensive simulation. By this means, we show that the inclusion of LTE constraints is essential to achieving high performance.

Defence : 09/22/2016

Jury members :

VÈQUE Véronique, Professeur Université Paris-Sud L2S, [Rapporteur]
ACHIR Nadjib, MCF HDR Université Paris 13, L2TI [Rapporteur]
MARTIN Steven, Professeur Université Paris-Sud, LRI
BAEY Sébastien, MCF UPMC

Departure date : 09/22/2016

2015-2017 Publications