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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

A study on Android games : 3G energy consumption, CPU-utilization and system calls

Almquist, Mathias, Almquist, Viktor January 2015 (has links)
The popularity of mobile games has increased drastically during the recent years andmany people use them as their main source of entertainment. Mobile gamescommunicate with other devices over the network which consumes a lot of energy,especially when connected to cellular networks (e.g., 3G). This high energy expensecan feel unjustified to the player since always-on network connectivity is not requiredin order to play most games.Furthermore, the number of malware-infected applications in offical applicationstores has increased significantly in the recent years. These malware-infectedapplications can gain unrestricted access and control of users phones which can be athreat to security. Information about the behaviour characteristics of games can beused to develop or improve systems for detecting malware applications.In this thesis, 20 popular Android games are analysed with a focus on the datacommunication, CPU utilization and system call behaviour. The main subject of thedata communication study is the 3G communication energy consumed by games. Thesystem call study aims at quantifying the number and type of calls used by games.This may be useful in a further study of harmful behaviour by apps.The profiling results presented in this report show that the communication energyvaries drastically among games. Games with a very similar gameplay can consumevery different amounts of energy which indicates that there is room for improvementsin many of the games. Ad-free games consume significantly less energy than gamesthat use in-app advertisements. The results show that improving the advertisementfetching policy could reduce the energy consumption of these games. The majority ofthe games can be played without network connectivity and therefore thecommunication energy consumed could be completely avoided. The thesis alsoshows that games use a wide variety of system calls and that many of the system callsare common among the games.
22

Energy Consumption Studies for 3G Traffic Consolidation on Android using WiFi and Bluetooth

Moreno Arocena, Ugaitz January 2014 (has links)
Mobile phones have evolved from being devices just to make phone calls to become smartphones with added capabilities like surfing the network. Wireless communication has played a very important role in the evolution of smartphones. The work in this thesis aims to study the potential to reduce the energy consumption of the 3G communications by using a hybrid architecture. An idea first presented in the paper by Vergara and Nadjm-Tehrani [1]. This architecture consists of a group of nodes that communicate using WiFi or Bluetooth to forward their traffic using one node's 3G interface. In this thesis the named energy sharing scheme is implemented on Android mobile devices and experiments have been performed using a number of realistic traces to assess achievable gains and the energy footprint of the scheme itself. Even though communication technologies, screen features, multimedia capabilities, or processing power have been taken to the highest level, phones' batteries have not improved at the same speed. Nowadays battery lifetime has become a major issue with respect to cellular communication. With 3G communications Internet connection anytime and anywhere is provided to the terminals but this technology is optimized for peak performance whereas in underutilization it wastes a lot of energy. This makes it a big black hole from power consumption point of view when transmitting small amounts of data.
23

A Unified Mobility Management Architecture for Interworked Heterogeneous Mobile Networks

Munasinghe, Kumudu S January 2009 (has links)
Doctor of Philosophy (Ph.D.) / The buzzword of this decade has been convergence: the convergence of telecommunications, Internet, entertainment, and information technologies for the seamless provisioning of multimedia services across different network types. Thus the future Next Generation Mobile Network (NGMN) can be envisioned as a group of co-existing heterogeneous mobile data networking technologies sharing a common Internet Protocol (IP) based backbone. In such all-IP based heterogeneous networking environments, ongoing sessions from roaming users are subjected to frequent vertical handoffs across network boundaries. Therefore, ensuring uninterrupted service continuity during session handoffs requires successful mobility and session management mechanisms to be implemented in these participating access networks. Therefore, it is essential for a common interworking framework to be in place for ensuring seamless service continuity over dissimilar networks to enable a potential user to freely roam from one network to another. For the best of our knowledge, the need for a suitable unified mobility and session management framework for the NGMN has not been successfully addressed as yet. This can be seen as the primary motivation of this research. Therefore, the key objectives of this thesis can be stated as:  To propose a mobility-aware novel architecture for interworking between heterogeneous mobile data networks  To propose a framework for facilitating unified real-time session management (inclusive of session establishment and seamless session handoff) across these different networks. In order to achieve the above goals, an interworking architecture is designed by incorporating the IP Multimedia Subsystem (IMS) as the coupling mediator between dissipate mobile data networking technologies. Subsequently, two different mobility management frameworks are proposed and implemented over the initial interworking architectural design. The first mobility management framework is fully handled by the IMS at the Application Layer. This framework is primarily dependant on the IMS’s default session management protocol, which is the Session Initiation Protocol (SIP). The second framework is a combined method based on SIP and the Mobile IP (MIP) protocols, which is essentially operated at the Network Layer. An analytical model is derived for evaluating the proposed scheme for analyzing the network Quality of Service (QoS) metrics and measures involved in session mobility management for the proposed mobility management frameworks. More precisely, these analyzed QoS metrics include vertical handoff delay, transient packet loss, jitter, and signaling overhead/cost. The results of the QoS analysis indicates that a MIP-SIP based mobility management framework performs better than its predecessor, the Pure-SIP based mobility management method. Also, the analysis results indicate that the QoS performances for the investigated parameters are within acceptable levels for real-time VoIP conversations. An OPNET based simulation platform is also used for modeling the proposed mobility management frameworks. All simulated scenarios prove to be capable of performing successful VoIP session handoffs between dissimilar networks whilst maintaining acceptable QoS levels. Lastly, based on the findings, the contributions made by this thesis can be summarized as:  The development of a novel framework for interworked heterogeneous mobile data networks in a NGMN environment.  The final design conveniently enables 3G cellular technologies (such as the Universal Mobile Telecommunications Systems (UMTS) or Code Division Multiple Access 2000 (CDMA2000) type systems), Wireless Local Area Networking (WLAN) technologies, and Wireless Metropolitan Area Networking (WMAN) technologies (e.g., Broadband Wireless Access (BWA) systems such as WiMAX) to interwork under a common signaling platform.  The introduction of a novel unified/centralized mobility and session management platform by exploiting the IMS as a universal coupling mediator for real-time session negotiation and management.  This enables a roaming user to seamlessly handoff sessions between different heterogeneous networks.  As secondary outcomes of this thesis, an analytical framework and an OPNET simulation framework are developed for analyzing vertical handoff performance. This OPNET simulation platform is suitable for commercial use.
24

Jag ser inte vad du säger : En studie av dövas subjektiva upplevelse av kvaliteten på kommunikation via 3G-telefoner

Björk, Jenny January 2006 (has links)
<p>Teckenspråket är ett visuellt språk, med möjligheter att uttrycka mycket information simultant. Faktorer som har en avgörande betydelse för språket är handens form, placering och rörelse, i kombination med ögon- och munrörelser. Utvecklingen av videosamtal via 3G har inneburit att döva kan konversera mobilt på sitt modersmål. Tidigare har de i många situationer varit hänvisade till sitt andraspråk, svenska. Denna uppsats undersöker hur döva upplever kvaliteten på kommunikation via videosamtal, samt huruvida de för teckenspråket viktiga faktorerna får tillräckligt med utrymme i dagens 3G-telefoner. Studien är av kvalitativ art och metoden som använts är framför allt intervju. Resultaten visar att kvaliteten upplevs som sämre än vid kommunikation öga mot öga, bland annat till följd av att vissa teckenspråkliga element inte kan kommuniceras med dagens teknik. Språket anpassas på så vis att enklare tecken används, de utförs långsammare och upprepas oftare. Av studien framgår att det finns ett behov av vidare forskning inom området, för att mobil teckenspråkig kommunikation ska fungera på ett för döva tillfredsställande sätt.</p>
25

Analýza českého telekomunikačního trhu / Analysis of the Czech telecommunications market

Hofman, Adam January 2016 (has links)
This diploma thesis focuses on the telecommunications field and specifically on the analysis of the Czech telecommunications market. Theoretical part of the thesis is focused on the historical development of telecommunications in terms of technological trends in the world and their subsequent transfer to Czech market. The practical part deals with the analysis of the Czech market, according to selected criteria, particularly in terms of privided services, their quality and technological solutions. The emphasis is on the analysis of operation of the mobile telecommunication and data services providers in the Czech Republic. The result of this diploma thesis is the analysis of the current state of the Czech telecommunications market in common with positive forecasts.
26

SROVNÁNÍ VYBRANÝCH MOBILNÍCH PŘIPOJENÍ K INTERNETU / Comparison of selected mobile Internet connection

Fialová, Ivana January 2008 (has links)
The topic of presented thesis is the subject of mobile Internet connectivity in the Czech Republic. The text is divided into two main parts. The first theoretical part is focused on an individual description of the technologies (GSM, GPRS, EDGE, UMTS and HSDPA) which are being offered in the Czech Republic by the operators. The greatest emphasis is put on a description of UMTS and HSDPA. The second part is practical; it describes the offers of each respective Czech operator focusing on the third-generation network or particularly the network operator with the highest connection speed. The thesis compares current offers against those in the year 2006. The next practical part is aimed at creating a methodology for testing mobile connections and its applications for UMTS and CDMA operator's tariffs at T-Mobile and Telefónica O2. The contribution of this work is to provide a comprehensive picture of a mobile Internet connection in the means of technological background and practical applications.
27

Analýza parametrů a komunikačních protokolů na rádiovém rozhraní sítí UMTS / Analysis of parameters and communication protocols on radio interface of UMTS networks

Plhák, Jan January 2010 (has links)
These times the third generation cellular networks are getting in use increasingly and they dramatically exceed the parameters of second generation networks. Third generation networks are in contrast to older generations data-oriented, providing better maintenance in data and multimedia services. The most widespread third generation network is the UMTS, designed as succesor of GSM network. Master’s thesis is focused on parameters and communication protocols of radio interface of UMTS network. Parameters of radio interface affect the behaviour of mobile terminal through utilization of network services. This thesis describes individual protocols of radio interface and individual procedures, which the mobile terminal have to perform through its staying in the cell. Theoretical part of this thesis considers description of the UMTS network and individual procedures and parameters. Practical part is focused on measuring the radio interface and individual procedures in real UMTS networks. Some procedures are simulated in network simulation software. This thesis includes a lab task focused on this thema.
28

A Network System Level Simulator for Investigating the Interworking of Wireless LAN and 3G Mobile Systems

Mann, Tracy L. 01 May 2003 (has links)
Recent research supports the eventual convergence of wireless LAN (WLAN) and cellular systems in order to achieve the IMT-2000 (3G) requirement for 2 Mbps indoor capacities. The WLAN access point can be enhanced to either incorporate or supplant the transmission and packet data capabilities in the cellular network. This research used OPNET™ to design, implement, and test a network system level simulation environment to allow investigators to study the issues and trade-offs for interworking the infrastructure-based WLAN technologies into 3G mobile subscriber cellular systems. The specific contribution of this research was to augment the current OPNET™ model library by creating an enhanced user equipment node (UW) and an enhanced WLAN access point node (UWLAN_AP). The UW was augmented with the capability to selectively gain network access through either a UMTS Node-B or through a 3G-aware WLAN access point. The UWLAN_AP was made 3G-aware by augmenting it with the capability to process UMTS control messages in order to build an access control table to support UMTS authentication and access control. Together, the UW and UWLAN_AP create a simulation framework for interworking the WLAN technology into UMTS as an alternate radio access network for supporting "hot spots." This research is the foundation to allow investigators to identify signaling and data transfer mechanisms that leverage the capabilities of WLAN while supporting cellular service provisioning and accountability requirements for current and future systems. / Master of Science
29

[en] METHODS FOR WCDMA SYSTEMS PLANNING / [pt] MÉTODOS DE PLANEJAMENTO DE SISTEMAS CELULARES WCDMA

MARIANA MOSTARDEIRO 28 June 2004 (has links)
[pt] Este trabalho apresenta um estudo detalhado de técnicas de planejamento de sistemas celulares de terceira geração WCDMA. Primeiramente é realizado um estudo teórico do sistema WCDMA, da estrutura da interface aérea, dos diversos tipos de canais presentes no downlink e no uplink. A seguir são aprentadas técnicas de planejamento de rede, com uma análise detalhada do cálculo de enlace e do planejamento de cobertura do sistema celular. Com base neste estudo foram realizadas diversas simulações com o software aberto NPSW para diferentes situações em relação a tipos de serviço, condições de uso e carga no sistema. Estas simulações permitiram caracterizar os efeitos dos diversos parâmetros de entrada no desempenho do sistema. Finalmente, é apresentado um estudo de caso de planejamento para a região do centro do Rio de Janeiro. / [en] This work presents a detailed study of planning tecniques for third generation WCDMA cellular systems. At first a theoretical study of the WCDMA system is presented, including the structure of the air interface and the various channel types in the downlink and uplink. Following, network planning techniques are presented, with a detailed analysis of the link budget calculations and the system coverage planning issues. Based on this study, the system behaviour was simulated using the open software NPSW for different configurations of service, operation condition and system load. The simulations allowed the characterization of the effect of several parameters on the system performance. Finally, a case study of coverage planning for downtown Rio de Janeiro is presented.
30

3G-masters miljöpåverkan : En studie av länsstyrelsens hantering av samråd enligt 12 kap. 6§ miljöbalken / Environmental impact from 3G masts : A study of how county administrative boards, Länsstyrelsen, handles consultation according to 12 kap. 6§ miljöbalken

Händel, Sofia January 2003 (has links)
<p>När rumsligt omvälvande projekt skall genomföras är det ofta konsekvenserna för naturmiljö, kulturmiljö, estetiska miljöaspekter som ger upphov till diskussioner. Uppförandet av telemaster till mobiltelefonsystemet 3G är ett infrastrukturprojekt som kommer att vara visuellt påtagliga på många platser i landskapet. I Sverige uppförs två stycken parallella mastsystem och detta har givit upphov till diskussioner kring projektets påverkan på vår omgivning. Uppsatsen studerar hur miljöpåverkan från ett stort infrastrukturprojekt, uppförandet av telemaster för 3G-systemet, behandlats av länsstyrelsen i samrådsärenden enligt 12 kapitlet 6§ miljöbalken, samt diskuterar kring hur handläggare på länsstyrelsen hanterar och upplever dessa ärenden. </p><p>Studien visar att handläggare på de undersökta länsstyrelserna har begränsat mandat att minska antalet master genom samlokalisering. Önskemålen om att teleoperatörerna ska dela på själva masten är svåra att genomföra eftersom operatörerna inte har samverkansavtal. Laglig rätt att förplikta samlokalisering fanns inte under den studerade perioden. Det är vanskligt att säga om den sammantagna inverkan som masterna sägs ha kunnat begränsas på denna nivå. Det som identifierats som ett problem av aktörer som Boverket och PTS, d.v.s. antalet master, fastlades redan i ett tidigare skede. </p><p>Samråden är inriktade på att undvika ur naturmiljösynpunkt olämpliga mastplaceringar. Dock utgör den fastslagna utbyggnaden av nätet och kravet på geografisk täckning att det kan uttryckas som att det för länsstyrelsen är inte en fråga om i fall masterna ska uppföras, utan om var. Lokaliseringen av masterna blir ett samspel mellan var operatörerna föredrar att placera master samt var det är lämpligt ut naturmiljösynpunkt. Den på nationell nivå fastlagda geografiska täckningskravet gör att bedömningen av masters påverkan på vissa landskap, där intrycket i landskapsbilden blir stort, upplevs svår av de intervjuade handläggarna. Bedömning av masters påverkan på just landskapsbilden kan upplevas som subjektiv. </p><p>Det stora antalet anmälningar om samråd har resulterat i få förelägganden och förbud. MKB har endast använts i ett litet antal fall. Samråden synes mycket inriktade på att hitta alternativa lösningar innan förbud utfärdas. Landskapsbilden är den enskilda motivering till förbud som förekommer flest gånger.</p>

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