Interference model and antenna parameters setting effects on 4G-LTE networks coverage

International audienceThe currently emerging Long Term Evolution 4G-LTE cellular networks are based on new technique of transmission called the Orthogonal Frequency Division Multiple Access (OFDMA). This paper shows the interest of robust approach due to the uncertainty of traffic distribution. First, we develop and validate the interference model based on SINR metric for the deployment of the LTE network, and then we use greedy algorithms to show how frequency and tilt parameter settings can impact the coverage performance metric. Two frequency schemes have been compared to validate our model: the frequency reuse 1 scheme whereby the whole available bandwidth is used in each cell/sector and the frequency reuse 3 scheme in which the entire bandwidth is divided into 3 non-overlapping groups and assigned to 3 co-site sectors within each cell

Impact des paramètres antennaires sur la couverture dans les réseaux LTE

National audienceLa demande en trafic dans les réseaux de radiocommunication a augmenté d'une manière vertigineuse ces dernières années [3]. Dans les réseaux LTE (Long Term Evolution), plusieurs recherches sur le paramétrage des antennes [1, 2] ont été effectuées pour répondre aux besoins des utilisateurs et augmenter les performances du système. Diverses combinaisons de paramètres d'antenne ont été étudiées en termes de performance en SINR (Signal to Interference plus Noise Ratio) et en débit [1, 2]. Nous proposons d'évaluer à la fois le SINR et le débit pour différents schémas de fréquence dans le cas d'un réseau LTE. Ce dernier est construit sur la base d'un réseau GSM/UMTS réel tri-secteurs (Territoire de Belfort), pour lequel le trafic est translaté sur le mode LTE. Ce travail permet d'analyser finement les stations mobiles (position, signal reçu, débit offert...) durant toute une journée de trafic. Nous proposons une méthodologie pour modifier automatiquement certains paramètres antennaires (tilt, fréquence d'émission) afin que le réseau réponde au mieux aux variations de trafic et d'environnement

Interference model and evaluation in LTE networks

International audienceThe purpose of this paper is to evaluate the impact of frequency parameter settings while evaluating interference model in LTE (Long Term Evolution); the work is applied on a network. We develop and validate the interference model based on SINR which is used by 3GPP (3rd Group Partnership Project) to estimate the quality of signal received by UE (User Equipment) and issued from eNB (enhanced Node Base). For this aim, two frequency schemes have been compared: the frequency reuse 1 scheme whereby the whole available bandwidth is used in each cell/sector and the frequency reuse 3 scheme in which the entire bandwidth is divided into 3 non-overlapping groups and assigned to 3 co-site sectors within each cell

A new model for indoor WLAN positioning system

National audienceIn this paper we attempt to answer the following question : how to deploy a WLAN in order to guarantee the requested Quality of Service (QoS) while reducing the location error ? Such a problem includes two aspects : WLAN planning and positioning error reduction. To provide users an optimal wireless access to their local network, WLAN planning not only consists in selecting a location for each transmitter and setting the parameters of all sites, but also acts on allocating one of the available frequencies to each Access Point (AP) configuration [1]. And toward the indoor positioning system, once the Received Signal Strengths (RSSs) from all visible APs are measured and inputted, the location is estimated and outputted using the RSS distribution and machine learning technique [2]. We propose a new approach where WLAN planning and positioning error reduction are modeled as an optimization problem and tackled together during WLAN planning process

Optimisation robuste dans les réseaux de radiocommunications

National audienceLes réseaux de communication mobile doivent écouler un trafic de plus en plus important. Pour ce faire, les réseaux auto-organisés SON (Self Organizing Networks) proposent des solutions qui visent à augmenter leur capacité en s'adaptant le mieux possible à la demande des clients. Dans ce cadre, la future norme de téléphonie mobile LTE [1] inclut des fonctions d'auto-organisation dont le but de réduire à la fois la complexité du paramétrage, les coûts d'investissements et les coûts d'exploitation. Notre étude porte sur l'optimisation du paramétrage de réseaux de communication mobile. Les données d'entrée du modèle sont les demandes en trafic des clients. Elles proviennent de prévisions et sont donc incertaines. Nous présentons alors une optimisation robuste qui permet de trouver de bons paramètrages, peu sensibles aux variations de trafic

Dynamic Purpose Decomposition of Mobility Flows Based on Geographical Data

Spatial and temporal decomposition of aggregated mobility flows is nowadays a commonly addressed issue, but a trip-purpose decomposition of mobility flows is a more challenging topic, which requires more sensitive analysis such as heterogeneous data fusion. In this paper, we study the relation between land use and mobility purposes. We propose a model that dynamically decomposes mobility flows into six mobility purposes. To this end, we use a national transportation database that surveyed more than 35,000 individuals and a national ground description database that identifies six distinct ground types. Based on these two types of data, we dynamically solve several overdetermined systems of linear equations from a training set and we infer the travel purposes. Our experimental results demonstrate that our model effectively predicts the purposes of mobility from the land use. Furthermore, our model shows great results compared with a reference supervised learning decomposition

Fitness Landscape Analysis for Scalable Multicast RRM Problem in Cellular Network

International audienceThis paper aims to solve the Radio Resource Management (RRM) problem for Multimedia Broadcast Multicast Service (MBMS) system in cellular network. We develop a flexible model to perform dynamic radio resource allocation for MBMS service by using metaheuristic approach. We conduct fitness landscape analysis to study the characteristics of the proposed model, which helps us to select appropriate search strategy. Simulation results show that the proposed algorithm provides better performance than existing algorithms. Keywords: fitness landscape, metaheuristic approach, multimedia multicast, radio resource management

Search for direct production of charginos and neutralinos in events with three leptons and missing transverse momentum in √s = 7 TeV pp collisions with the ATLAS detector

A search for the direct production of charginos and neutralinos in final states with three electrons or muons and missing transverse momentum is presented. The analysis is based on 4.7 fb−1 of proton–proton collision data delivered by the Large Hadron Collider and recorded with the ATLAS detector. Observations are consistent with Standard Model expectations in three signal regions that are either depleted or enriched in Z-boson decays. Upper limits at 95% confidence level are set in R-parity conserving phenomenological minimal supersymmetric models and in simplified models, significantly extending previous results

Observation of associated near-side and away-side long-range correlations in √sNN=5.02 TeV proton-lead collisions with the ATLAS detector

Two-particle correlations in relative azimuthal angle (Δϕ) and pseudorapidity (Δη) are measured in √sNN=5.02  TeV p+Pb collisions using the ATLAS detector at the LHC. The measurements are performed using approximately 1  μb-1 of data as a function of transverse momentum (pT) and the transverse energy (ΣETPb) summed over 3.1<η<4.9 in the direction of the Pb beam. The correlation function, constructed from charged particles, exhibits a long-range (2<|Δη|<5) “near-side” (Δϕ∼0) correlation that grows rapidly with increasing ΣETPb. A long-range “away-side” (Δϕ∼π) correlation, obtained by subtracting the expected contributions from recoiling dijets and other sources estimated using events with small ΣETPb, is found to match the near-side correlation in magnitude, shape (in Δη and Δϕ) and ΣETPb dependence. The resultant Δϕ correlation is approximately symmetric about π/2, and is consistent with a dominant cos⁡2Δϕ modulation for all ΣETPb ranges and particle pT