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Optimal Call Admission Control Policies in Wireless Cellular Networks Using Semi Markov Decision ProcesNi, Wenlong January 2008 (has links)
No description available.
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Integration of Open-Source NetworksCooper, Thomas A. 10 May 2012 (has links)
Global System for Mobile Communications (GSM) networks are receiving increasing attention in the open-source community. Open-source software allows for deployment of a mobile cellular network with lower costs, more customization, and scalable control. Two popular projects have emerged that offer varying network architectures and allow users to implement a GSM network in different capacities depending on individual needs. Osmocom provides more network control and scalability but requires commercial Base Transceiver Station (BTS) hardware with limited availability and closed source code. OpenBTS provides minimal GSM network functionality with more easily available and open-source hardware; however, it does not allow multi-cellular network configuration.
This thesis offers a significant contribution towards a fully open-source GSM network by integrating the two major open-source communities, Osmocom and OpenBTS. Specifically, the Osmo-USRP program provides an inter-layer interface between the different network architectures of two GSM base station projects. Inter-layer primitive messages are processed in a thread multiplexer that manages logical channels across the interface. Downstream flow control is implemented in order to receive data frames on time for transmitting at the appropriate GSM frame number (FN). Uplink measurements, which are necessary for decision making in the Base Station Controller (BSC), are also gathered in the physical layer of Osmo-USRP and reported to Osmocom.
Osmo-USRP operation is tested using a Universal Software Radio Peripheral (USRP), a relatively inexpensive and accessible Software-Defined Radio (SDR). Standard GSM events are investigated for single cell and multi-cellular network configurations. These tests include subscriber authentication and encryption, location updating, International Mobile Subscriber Identity (IMSI) attach and detach, Short Message Service (SMS) storage and delivery, voice calls with the full-rate audio codec, and uplink and downlink measurement reporting. While most functionality is successfully tested, inter-cell handover is not currently implemented. Further details on the proposed implementation of program limitations, especially inter-cell handover, are also discussed. / Master of Science
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應急蜂巢式行動通訊網路之群組通訊設計 / Agency Communication Design for Contingency Cellular Network張惠晴, Chang, Hui Ching Unknown Date (has links)
在大型天然災害發生之後的黃金救援時期,災民存活率和救災效益之提昇極度仰賴於一個順暢的通訊系統。由歷年來大型災變的經驗中我們可知,行動通訊系統其實是不可靠且極為脆弱的,基地台之電力供應中斷或連接後端固定網路線路(Backhaul)之損毀都將使得通訊系統癱瘓而影響救災工作效率。
本研究提出一種新的應急通訊系統,利用原有行動通訊系統中未損毀但失去連網能力的基地台,藉由臨時供應的電力恢復其運轉,並以無線通訊設備與鄰近基地台互連建構一個臨時應急性的網路,稱為應急蜂巢式行動通訊網路(Contingency Cellular Network,CCN),供災區內手機用戶進行通訊。由於災區內部通訊的對象通常是一個特定的群組角色,而非一個特定人員,而災民與救災人員也不知彼此所在位置及聯絡的方式,因此無法以平常的撥號方式發起呼叫。本研究以CCN網路架構為基礎,設計並實作群組通訊模式,讓災區內人員以簡碼方式向任一群組發起呼叫並建立通話。
為驗證CCN群組通訊設計之可行性及效能,我們以IEEE802.11 Wi-Fi無線網路環境建置模擬系統,並以Android平台手機搭配VoIP軟體模擬手機與系統連線以進行通話。最後設計了一連串的實驗評估本模擬系統之效能。從實驗結果可知,本系統可於短時間內即時回應使用者註冊需求及完成通話連線處理;當通話數在30通以下時,Mouth-to-Ear Delay (MED) 值可維持在400ms以下,語音品質控制在一般VoIP使用者可容許的範圍之內。本實驗可作為未來改進系統功能和建置架構之參考依據。 / When stricken by a catastrophic natural disaster, the efficiency of disaster response operation is very critical to life saving. The efficiency of disaster response operation is greatly depending on communication systems. However, they were usually not dependable, including cellular networks, and often crashed due to power outage and backhaul link breakage. The failure of communication systems caused a big coordination problem to many disaster response operations.
This thesis proposes a Contingency Cellular Network (CCN) by connecting isolated base stations to survival base stations using long-range wireless links to restore part of cellular network functionality. People can use their own cell phones for emergency communication in the disaster areas. CCN will be able to support many disaster response workers in the early hours of catastrophic natural disasters, thus to save many lives.
Since the receiver of a phone call in a disaster area is usually a resource (agent), not a particular person, we designed a special Agency communication mode for CCN allowing CCN users to initiate a phone call to a nearby resource by dialing a designated agency number, instead of a real phone number. To verify our design, we implemented an emulated CCN system using an IEEE 802.11 Wireless LAN to mimic the CCN network and Android small phones with VoIP software to mimic user terminals.
Finally, we conducted a series of experiments to evaluate the performance of the emulated system. The experimental results show that the emulated system can respond promptly to the user registration and call set-up requests. Mouth-to-Ear Delay (MED) can be effectively controlled below 400 ms when there is no more than 30 calls originated. This system may be used as reference for the future development of contingency communication networks.
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Indoor/Outdoor Location of Cellular Handsets Based on Received Signal StrengthZhu, Jian 19 May 2006 (has links)
Indoor/Outdoor Location of Cellular Handsets Based on Received Signal Strength
Jian Zhu
123 pages
Directed by Dr. Gregory D. Durgin
Accurate geo-location is an important emerging technology for public safety, commercial use, and military application. Especially, in the United States, the wireless Enhanced 911 (E911) rules by the Federal Communication Commission (FCC) seek to provide 911 dispatchers with additional information on wireless 911 calls.
This dissertation presents a novel technique for indoor/outdoor location of cellular handsets based on received signal strength (RSS) measurements taken by a cellular handset of the surrounding base stations. RSS location accuracy for different environments is studied as a function of base station separation distance, cell sector density, measurement density, radio propagation environment, and accuracy of measurement. The analytical and experimental results in this thesis serve as a guideline for the accuracy of RSS signature location technology under different conditions. Accurate outdoor to indoor penetration models are proposed and validated for dense urban areas by introducing pseudo-transmitters to simulate the wave-guiding effects in urban canyon environments. A set of location algorithms is developed to improve location accuracy. Furthermore, an algorithm to discriminate between indoor and outdoor users is proposed and validated. The research results demonstrate the feasibility of RSS location techniques to meet the FCCs requirements for E911 accuracy in urban and semi-urban environments. The techniques remain accurate for indoor handsets. The results also suggest that a hybridization of the handset-based GPS method and the RSS signature method may prove to be the most effective solution for locating handsets across a range of environments; including rural, suburban, dense urban, and indoor.
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Route Assignment for Distributed Leased Lines in Mobile Cellular NetworkHuang, Yung-chia 09 July 2007 (has links)
When a large number of base stations fail due to the breakdown of some transmission circuit in a mobile cellular network, base stations located in neighboring areas may take over those malfunctioned base stations and continue to provide the access service of mobile communications for users in surrounding areas, thereby reducing the area in which mobile communications are out of service. Therefore, if leased circuits in base stations could complete the route distribution configuration prior to the onset of malfunction, it could decrease the impact of circuit breakdown and traffic loss. Also, the efficiency would be improved if the circuit assignment personnel could complete the job when the leased lines are less, while avoiding reassignment in the future and enhancing the mobile communications operations.
In this study, we use a graph structure to represent the present mobile cellular network and establish the route-selection strategies. We define the "Optimal Route Assignment" for a newly constructed base station, which refers to the route assignment that causes least impact on disconnection area when any circuit in the network is broken. We also propose to use A* algorithm for optimal route assignment. However, the computation for the optimal route is time consuming. Measures such as computation time and least hops are considered in designing other strategies for route assignment. These strategies are parametric and we carried out experiments by adjusting and controlling parameters using real routing data.
The experimental results demonstrate that there is no single winner among the proposed strategies. We identify a number of best strategies for different operating regions.
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應急蜂巢式行動網路的拓撲設計 / Topology design for contingency cellular network黃玉潔, Huang, Yu Chieh Unknown Date (has links)
大型災害頻傳傷亡慘重,若能把握於救災黃金72小時內救出受困民眾,則可望挽回更多寶貴的生命,但災區通訊網路基礎設施常因災害而遭受嚴重損毀,無法正常運作。救災工作在缺乏通訊系統的支援下,因溝通協調的困難而紊亂無章、效率低落。
本研究提出一個可快速恢復特定區域通訊服務的網路,並為其設計通訊的拓撲結構。我們稱該網路為應急蜂巢式行動通訊網路(Contingency Cellular Network),簡稱CCN網路。CCN網路利用無線電連接災區行動電話網路中斷訊但結構未損的基地台建構而成,具有建置速度快、使用門檻低等多項特點,可支援災區救援的緊急通訊。
本研究中,我們以各毀損基地台通訊範圍內的通訊需求人數與災區毀損程度,作為效益參數,嘗詴在蜂巢式網路的格網架構以及數量有限的緊急通訊設備下,選擇效益較高的位置點配置緊急通訊設備,建立應急蜂巢式行動網路的網路拓撲,此拓撲除追求最大救災效益外,並顧及通訊品質,避免建立負載失衡的連線。我們將問題塑模為一類似圖論中的K-Minimum Cost Spanning Tree (K-Cardinality Tree or KCT)問題,稱為Depth Bounded K-Maximum Profit Spanning Tree問題,並提供數個快速的啟發式演算法,可在緊急時快速地建立應急蜂巢式行動網路拓撲。 / When a catastrophic natural disaster occurs, the efficiency of disaster response operation is critical to life saving. However, communication systems, such as cellular networks, usually crashed due to various causes that make coordination difficult for many disorganized disaster response workers extremely. Unfortunately, rapid deployment of many existing emergency communication systems relies on a good transportation system, which is usually not available in a catastrophic natural disaster. We propose a Contingency Cellular Network (CCN) by connecting disconnected base stations together with wireless links and portable power generators. CCN can support existing mobile phone users with limited capability. Such a system can support a large number of voluntary workers in the early hours of a catastrophic natural disaster, thus saving many lives.
Communication traffics, either voice or data, are forwarded hop-by-hop to the external network that remains operational. The efficiency and effeteness of CCN is obviously depends on the topology of such a forwarding network. This thesis addresses the design of forwarding topology aiming to maximize its efficiency. We take the degree of emergency degree of the damage, population of each stricken as the priority measure as well as the amount of emergency recovery resources as the constraint to determine the topology. We model the CCN topology design problem into a Depth Bounded K-Maximum Spanning Tree Problem. The problem is proven NP-hard and we designed an efficient heuristic algorithm (DBTB) to solve it. We also model CCN topology design problem into a Hop Concerned K-Maximum Spanning
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Tree Program and designed a HCTB algorithm to solve it. The simulation results show that DBTB algorithm can control tree depth effectively but HCTB can gain more profit.
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Analysis and exploitation of mobile traffic datasets / Analyse et exploitation de données de trafic mobileNaboulsi, Diala 24 September 2015 (has links)
Les équipements mobiles deviennent une partie intégrale de notre vie numérique. Ces équipements interagissent avec l'infrastructure des réseaux cellulaires et leur activité est enregistrée pour des buts de facturation et monitoring sous forme de données de trafic mobile. Les travaux menés dans cette thèse se focalisent sur le potentiel que portent ces données pour l'amélioration des réseaux cellulaires futurs. D'une part, on montre que les données mobiles permettent de construire des profils spatio-temporels typiques de l'utilisation des réseaux cellulaires en environnement urbain. Cette analyse permet aussi la détection des comportements atypiques dans le réseau qui sont liés à des événements spéciaux. D'autre part, on montre que les données mobiles constituent un élément méthodologique important pour l'évaluation des solutions réseaux. Dans ce sens, on propose un mécanisme pour réduire la consommation énergétique des infrastructures cellulaires, en contrôlant la puissance sur le réseau d'accès à différents moments de la journée, tout en assurant la couverture géographique du réseau. On exploite aussi ces données pour évaluer les gains apportés par une nouvelle architecture de réseau d'accès, basée sur la virtualisation d'une partie du réseau et sa centralisation dans un cloud. Nos résultats montrent que cette architecture est bénéfique du point de vue des messages de signalisation, notamment pour les utilisateurs mobiles. / Mobile devices are becoming an integral part of our everyday digitalized life. In 2014, the number of mobile devices, connected to the internet and consuming traffic, has even exceeded the number of human beings on earth. These devices constantly interact with the network infrastructure and their activity is recorded by network operators, for monitoring and billing purposes. The resulting logs, collected as mobile traffic datasets, convey important information concerning spatio-temporal traffic dynamics, relating to large populations with millions of individuals. The thesis sheds light on the potential carried by mobile traffic datasets for future cellular networks. On one hand, we target the analysis of these datasets. We propose a usage patterns characterization framework, capable of defining meaningful categories of mobile traffic profiles and classifying network usages accordingly. On the other hand, we exploit mobile traffic datasets to evaluate two dynamic networking solutions. First, we focus on the reduction of energy consumption over typical Radio Access Networks (RAN). We introduce a power control mechanism that adapts the RAN's power configuration to users demands, while maintaining a geographical coverage. We show that our scheme allows to significantly reduce power consumption over the network infrastructure. Second, we study the problem of topology management of future Cloud-RAN (C-RAN). We propose a mobility-driven dynamic association scheme of the C-RAN components, which takes into account users traffic demand. The introduced strategy is observed to lead to important savings in the network, in terms of handovers.
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Optimization of resource allocation in small cells networks : A green networking approach / Optimisation d'allocation des ressources aux petits réseaux de cellules : Une approche en réseau vertHasan, Cengis 29 August 2013 (has links)
Le terme “réseau vert” ou pour éviter une traduction directe, “réseau propre” repose sur la sélection de technologies et de produits réseaux économes en énergie, et garantissant un usage minimal des ressources quand cela est possible. Cette thèse vise à étudier les problèmes d’allocation des ressources dans les petits réseaux de cellules dans un contexte de réseau propre. Nous développons des algorithmes pour différents paradigmes. Nos travaux reposent principalement sur le contexte de la théorie des jeux de coalition, mais également sur des outils de géométrie stochastique ainsi que d’un modèle de jeu de surpeuplement. Nous étudions tout d’abord le problème d’association de mobiles à des stations de base dans les applications de diffusion d’un flux commun, sous contrainte de minimisation de la consommation d’énergie totale: nos algorithmes suivent une approche préservant l’énergie. Nous examinons le problème d’association des mobiles sous le prisme des jeux de coalition. Ce jeu tend à former la grande coalition, qui se caractérise par le fait que tous les joueurs forment une coalition unique. Nous prouvons que ce jeu de coalition à un noyau non vide ce qui signifie que la grande coalition est stable. Dans une deuxième partie, nous analysons un problème important dans les réseaux propres qui consiste à éteindre les stations de base qui ne sont pas indispensables. Nous abordons ce problème de façon statistique, dans le cas de fournisseurs de services coopérant au moyen d’outils de jeux de coalition vus sous un angle de la géométrie stochastique. Le jeu coalitionnel considéré est joué par les fournisseurs de services qui collaborent à éteindre leurs stations de base. Nous avons analysé la stabilité de Nash qui est un concept utilisé pour les jeux de coalition hédoniques. Nous posons la question suivante: Existe-t-il une méthode de répartition de la fonction d’utilité qui se traduit par un partitionnement Nash-stable? Nous répondons à cette question dans la thèse. Nous démontrons que le noyau Nash-stable, défini comme l’ensemble des méthodes de répartition des couts conduisant à un partitionnement stable au sens de la stabilité de Nash. Nous considérons finalement les jeux liés à l’association des mobiles à un point d’accès. Le jeu consiste à décider à quel point d’accès un mobile doit se connecter. Nous considérons le choix entre deux points d’accès ou plus. Les décisions d’association dépendent du nombre de mobiles connectés à chacun des points d’accès. Nous obtenons de nouveaux résultats en utilisant des outils élémentaires de jeux de congestion et d’éviction. Nous étudions le problème de la sélection de partenaires dans le cas de constitution de binomes gagnant-gagnant, ou chacun des partenaires s’appuie sur l’autre pour sa propre transmission. Nous proposons d’assimiler la sélection des partenaires au problème classique en théorie des jeux de recherche stable de colocataire. / The term “green networking” refers to energy-efficient networking technologies and products, while minimizing resource usage as possible. This thesis targets the problem of resource allocation in small cells networks in a green networking context. We develop algorithms for different paradigms. We exploit the framework of coalitional games theory and some stochastic geometric tools as well as the crowding game model. We first study the mobile assignment problem in broadcast transmission where minimal total power consumption is sought. A green-aware approach is followed in our algorithms. We examine the coalitional game aspects of the mobile assignment problem. This game has an incentive to form grand coalition where all players join to the game. By using Bondareva-Shapley theorem, we prove that this coalitional game has a non-empty core which means that the grand coalition is stable. Then, we examine the cost allocation policy for different methods. In a second part, we analyze a significant problem in green networking called switching off base stations in case of cooperating service providers by means of stochastic geometric and coalitional game tools. The coalitional game herein considered is played by service providers who cooperate in switching off base stations. We observed the Nash stability which is a concept in hedonic coalition formation games. We ask the following question: Is there any utility allocation method which could result in a Nash-stable partition? We address this issue in the thesis. We propose the definition of the Nash-stable core which is the set of all possible utility allocation methods resulting in stable partitions obtained according to Nash stability. We finally consider games related to the association of mobiles to an access point. The player is the mobile which has to decide to which access point to connect. We consider the choice between two access points or more, where the access decisions may depend on the number of mobiles connected to each access points. We obtained new results using elementary tools from congestion and crowding games. Last but not least, we extend our work to cooperative transmissions. We formulate the partner selection problem in cooperative relaying based on a matching theoretic approach. Partner selection is described as a special stable roommate problem where each player ranks its partners by some criterion. We adapted Irving’s algorithm for determining the partner of each player. We introduced a decentralized version of the Irving’s algorithm.
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Experimentální rušička pro GSM sítě / Expertimental GSM jammerCharvát, Jiří January 2009 (has links)
This thesis describes GSM communication, the method of its jamming and design of a jammer for this band. This document is mainly focused on design of the jammer with the variable bandwidth of jamming and the variable level of output power. Requested parameters of jamming are set by a control panel with a LCD display. In this document there is a detailed description of each function block and connection between them. At the end of this thesis there are released measured results of designed jammer.
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Méthodes et outils d'analyse de données de signalisation mobile pour l'étude de la mobilité humaine / Methods and analysis tools for human mobility study, based on mobile network signaling dataSultan, Alexis 28 September 2016 (has links)
Cette thèse a pour but d’étudier les activités humaines à travers l’analyse du flux de signalisation du réseau cellulaire de données (GTP). Pour ce faire, nous avons mis en place un ensemble d’outils nous permettant de collecter, stocker et analyser ces données de signalisation. Ceci en se basant sur une architecture indépendante au maximum des constructeurs de matériel. À partir des données extraites par cette plateforme nous avons fait trois contributions.Dans une première contribution, nous présentons l’architecture de la plateforme de capture et d’analyse de la signalisation GTP dans un réseau d’opérateur. Ce travail a pour but de faire l’inventaire des différents éléments déclenchant des mises à jour et aussi d’estimer la précision temporelle et spatiale des données collectées. Ensuite, nous présentons une série de mesures, mettant en avant les caractéristiques principales de la mobilité humaine observées au travers de la signalisation mobile (le temps inter-arrivées des messages de mise à jour, la distance observée des sauts entre cellules lors des déplacements des clients). Finalement, nous présentons l’analyse des compromis qui ont été faits entre la rapidité d’écriture/de lecture et la facilité d’usage du format de fichier utilisé lors de l’échange d’informations entre les sondes de capture et le système stockage. Deuxièmement, nous avons été capables de mettre en place un algorithme de reconstitution de trajets. Cet algorithme permet, à partir de données éparses issues du réseau cellulaire, de forger des trajets sur les voies de transport. Il se base sur les données des trajets sous-échantillonnées et en déduit les positions du client sur les voies de communication. Nous avons mis en place un graphe de transport intermodal. Celui-ci porte sur le métro, le train et le réseau routier. Il connecte les différents points entre eux dans chacune des couches de transport et interconnecte les modes de transport entre eux, aux intersections. Notre algorithme se base sur un modèle de chaîne de Markov cachée pour placer sur le graphe les positions probables des individus entre les différentes observations. L’apport de ce travail est l’utilisation des propriétés topologiques du réseau de transport afin de renseigner les probabilités d’émission et de transition dans un modèle non supervisé. Ces travaux ont donné lieu à une publication et à un brevet. Finalement, notre dernière contribution utilise les données issues de la signalisation à des fins de dimensionnement du réseau mobile d’opérateur. Il s’agit de dimensionner dynamiquement un réseau mobile en utilisant les bandes de fréquences dites vTV-Whitespace. Ces bandes de fréquences sont libérées sous certaines conditions aux USA et soumises à vente aux enchères. Ce que nous proposons est un système basé sur un algorithme de qualité d’expérience (QoE) et sur le coût de la ressource radio afin de choisir où déployer des femtocells supplémentaires et où en supprimer en fonction des variations de population par unité d’espace. En conclusion, cette thèse offre un aperçu du potentiel de l’analyse des metadata de signalisation d’un réseau dans un contexte plus général que la simple supervision d’un réseau d’opérateur / The aim of this thesis is to study human activities through the analysis of the signaling flow in cellular data network (GTP). In order to achieve this goal, we implemented a set of tools allowing us to collect, store and analyze this signaling data. We created an architecture independent at most of hardware manufacturers and network operators. Using data extracted by this platform we made three main contributions. In our first contribution, we present the GTP capture and analysis platform in a mobile operator network. This work intends to list the different elements triggering updates and to estimate the temporal and spatial accuracy of the data collected. Next, we present a set of measures that represent the main characteristics of human mobility observed through the mobile signaling data (the inter-arrival time of update messages, the observed distances of hops from cell to cell made by moving users). Finally, we present the analysis of the compromise that was made between the writing/reading performances and the ease of use of the file format for the data storage. In our second contribution, we propose CT-Mapper, an unsupervised algorithm that enables the mapping of mobile phone traces over a multimodal transport network. One of the main strengths of CT-Mapper is its capability to map noisy sparse cellular multimodal trajectories over a multilayer transportation network where the layers have different physical properties and not only to map trajectories associated with a single layer. Such a network is modeled by a large multilayer graph in which the nodes correspond to metro/train stations or road intersections and edges correspond to connections between them. The mapping problem is modeled by an unsupervised HMM where the observations correspond to sparse user mobile trajectories and the hidden states to the multilayer graph nodes. The HMM is unsupervised as the transition and emission probabilities are inferred using respectively the physical transportation properties and the information on the spatial coverage of antenna base stations. Finally, in our last contribution we propose a method for cellular resource planning taking into account user mobility. Since users move, the bandwidth resource should move accordingly. We design a score based method using TV Whitespace, and user experience, to determine from which cell resource should be removed and to which one it should be added. Combined with traffic history it calculates scores for each cell. Bandwidth is reallocated on a half-day basis. Before that, real traces of cellular networks in urban districts are presented which confirm that static network planning is no longer optimal. A dynamic femtocell architecture is then presented. It is based on mesh interconnected elements and designed to serve the score based bandwidth allocation algorithm. The score method along with the architecture are simulated and results are presented. They confirm the expected improvement in bandwidth and delay per user while maintaining a low operation cost at the operator side. In conclusion, this thesis provides an overview of the potential of analyzing the signaling metadata of a network in a broader context that supervision of an operator network
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