Abstract The era of mobile communications and mobile services has begun. The ongoing mobile revolution has dramatically and fundamentally changed our daily lifestyles, and it will continue to do so in a foreseeable future. For the next generation, mobile service end users have more demands for such services. This thesis examines the challenging user perspectives in designing and developing high value added mobile services. The aim of this research is to develop reference models and elicit user requirements for 3G and beyond mobile services in order to improve the quality of mobile services. This thesis first examines the existing architectures and models for high value added mobile services, followed by the contributions of the thesis. In this thesis, a Cyberworld model, which is a contribution to the WWRF reference modeling initiative and a specification of the WSI reference model, was developed and it serves as a basis for 3G and beyond mobile services design and development. A series of definitions of the Cyberworld model and a roadmap of the enabling technologies were also built up. The emphasis of this part is on how to describe and model user participation in mobile services. For this purpose, a model of the communication element to represent the components of the wireless world was created. Both static and dynamic reference modeling steps were established to better describe and understand user participation in mobile services. The validation was achieved through the CyPhone navigation mobile service. In order to enhance mobile service mobility, personalisation, and security, an ontology based model was developed to extend the Cyberworld model functionalities. The innovative ontology based mobile system will greatly increase service mobility, personalisation and security, thus improving the quality of mobile services. The ontology based model was illustrated and validated using a healthcare mobile service. A Quality Function Deployment (QFD) approach was adopted in this research in order to elicit, weigh and prioritise actual user requirements and link them to technical design requirements of mobile services. Traditionally QFD is employed in manufacturing industry. This approach is now extended to the mobile service industry for the first time. In this thesis, a detailed step by step QFD approach was proposed for designing high value added mobile services. As a result, the developed mobile services will better meet users' wants and needs which also means that the quality of mobile services will be significantly improved. The QFD approach was validated through a mobile e-learning service and another dedicated healthcare service for senior citizens. Through development of reference models and examination of user requirements for 3G and beyond mobile services from user perspectives, this thesis contributes to the design and development of high value added mobile services.

This thesis treats the development of wirelessinfrastructure standards resulting from co-operative research,development and standardisation efforts. It strives to identifykey influences on this development process, and toconceptualise the process itself. With this as a basis, it goeson to analyse potential implications for companies in thewireless industry, and for the role of co-operatively developedstandards in this field. The focus of the thesis is on thecreation of standards through development efforts, rather thanthe selection of standards in official forums, or by themarket. Two deep empirical studies provide the foundation of thethesis. The first one deals with the development of the DigitalEnhanced Cordless Telecommunications (DECT) standard. DECT isan open, de jure standard that was designed by a number oftelecommunications manufacturers. The standard was formallyapproved by the European Telecommunications Standards Institute(ETSI) in 1992. The second study treats the development ofThird Generation (3G) mobile infrastructure standards, withspecial focus on the radio interface standards such as WidebandCode Division Multiple Access (WCDMA). The development of thefamily of 3G standards today known as International MobileTelecommunications 2000 (IMT-2000) began more than 15 yearsago, and the first version of formally adopted air interfacestandards was released in 2000 by the Third GenerationPartnership Project (3GPP). The research and development goinginto the specification of the standards has involved all majorplayers in the wireless industry. The two studies have involved numerous interviews withindustry professionals, academics, regulators, and others. Inaddition, a multitude of technical reports and articles,meeting documents, press releases, etc., have been analysed toprovide good documentation of the development processes. Theempirical studies have also been complemented with extensiveliterature studies into the areas of technical development andstandardisation. Apart from two "thick descriptions" of importantdevelopments in the wireless industry, the main result of thethesis is a conceptual framework for how wirelessinfrastructure standards are developed. The frameworkdemonstrates that the development is influenced by thepre-history of the standard in terms of existing systems, aswell as research and development that had been pursued inrelevant fields. Furthermore it shows that preconceptions ofmarket needs and user behaviour are key aspects of the designof the standard. During the development process technologicalcontroversies tend to appear as a manifestation of differentcompetitive intentions among the involved players. In theresolution of these controversies, the stage is set for futurecompetition between suppliers of products adhering to thestandard. The pre-history of a standard, as well as the marketpreconceptions, originate in the semi-independent processes oftechnological development, and market diffusion, respectively.When the time frame of the conceptual framework is expanded,generations of standards following upon each other can beidentified. Each new generation incorporates new developments,and improved functionality and performance, but also builds onexisting solutions. The technical standards, such as DECT orWCDMA, act as wasp-like waists between the technologicaldevelopment and the market diffusion processes. The thesis shows that wireless infrastructure standards to agreat extent are created through technical development efforts.The processes also involve political, competitive, andregulatory deliberations, but technical content often definesthe form even for these debates. This points to the importanceof considering standards-setting in terms of a developmentprocess rather than as a set of formal decisions made by astandards body. A consequence of this is that companiesdesiring to influence the design of a particular standardshould strive to be in the forefront of research anddevelopment related to that standardisation effort. This is thekey to leading the development of new wireless infrastructurestandards. Key words:standards, de jure standards,standardisation, standards-development, competition,technological development, wireless communications, wirelessinfrastructures, telecommunications, WCDMA, DECT, IMT-2000,FPLMTS, 3G / <p>NR 20140805</p>

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The master thesis is focused on control procedures in EPS-IMS networks. Firstly the thesis describes systems IMS and EPS. The second part of thesis includes the theory of control procedures in EPS such as cell acquisition, random access procedure, identification of subscriber, authentication of subscriber, security procedures, tracking area procedure, default bearer creation, implementation of CSFB procedure and detach procedure. Processes related to subsystem IMS such as registration to IMS, bearer creation for IMS signalling and voice service VoLTE are the next part of thesis. The next main topic is the VoLTE implementation problematic and VoLTE cooperation with diverse terminals. There is also explained the principle of Circuit Switched Fallback for realization voice services in EPS without VoLTE service. All procedures mentioned above except of procedures which are related to IMS were captured and analyzed using software Wireshark and QualiPoc. The final part of the thesis is lab task creation based of the analyzed messages.

The mobile communication technology has evolved from the first generation (1G), when the first radiotelephone service was introduced in the US in late 1940s, to the third generation (3G). In each generation, different standards and technologies were promoted by technologically and economically advanced countries. For example, the major 1G communication standards were: AMPS promoted by the US, NMT promoted by Nordic countries, and TACS promoted by the UK. The second generation (2G) communication standards include GSM promoted by the European countries and CDMA (IS-95) promoted by the US. Behind these different standards, there are entire industry chains and huge profits. To catch up with these forerunners, lagging countries usually need to go through different stages including duplicative imitation, creative imitation, and then real innovation. In the 1G era, China did not have its own standard, but it adopted the British TACS systems. In the 2G era, China did not have its own standard, and it adopted both the European GSM systems and the US CDMA systems. However, when the 3G era was approaching, China decided to seize the opportunity and developed its own 3G standard: TD-SCDMA. In January 2009, China issued three different 3G licenses to three different operators who utilized TD-SCDMA, WCDMA, and CDMA2000, respectively. The Chinese proposed 3G standard began to be commercialized with this first licensee. China has been trying to catch up with the leading countries in the mobile communication industry. This thesis examines the question of whether this catching-up process was successful or not. The purpose of this thesis is to give readers insights into the Chinese 3G market, and to help them to understand the catching-up process being undertaken by China’s mobile communication industry. The thesis first introduces some background information about 3G, TD-SCDMA, and the Chinese telecom market. Then, it reviews theories of technological catching-up and leapfrogging. After that, it presents a case study of the TD-SCDMA Industry Alliance that examines six determinants measuring the catching-up process: Sources for Competitive Advantages, Strategies and Policies, R&amp;D Efforts, R&amp;D Outcome, and Market Success. The final part of the thesis gives answers to the research question and reveals the profound impact brought by the catching-up process of China’s mobile industry.

The purpose of this study was to determine the availability of Internet access for students attending East Tennessee State University during the fall semester 2013. It has been unknown to what degree broadband access is available in the East Tennessee State University service area that includes counties in East Tennessee, Southwest Virginia, and Western North Carolina. The research was conducted during the fall semester 2013 including the months of August, September, and October of 2011. Data were gathered by surveying currently enrolled students of the university. Seven hundred eighty-four students responded to the survey. The survey instrument covered areas of demographics and Internet connection type from home. In addition, the instrument covered usage of 3G/4G Mobile Broadband Service, ETSU computer labs, and high-speed Internet service for coursework. The results of the data analysis provided insight into the availability, frequency of use, and perceived importance of high-speed Internet access for students at ETSU. For example, over 95% of the respondents had either a high-speed Internet connection or 3G/4G Mobile Broadband Service at their place of residence. Fifteen percent were dissatisfied with their current high-speed Internet service. Approximately 70% reported that high-speed Internet service was very important in completing coursework. This study provided an increase in the body of knowledge related to Internet access for ETSU students and the counties surrounding the university.

IP security (IPsec) is commonly used for protection in Virtual Private Networks (VPN). It is also used for the protection of traffic between nodes in third generation (3G) mobile networks. The main duty of telecommunication operators is to assure the quality of service and availability of the network for their users. Therefore knowledge of threats that could affect these requirements is of relevance. Denial of Service (DoS) and other attacks could constitute serious threats in 3G networks and, if successful, they could lead to financial and reputation damage for the telecommunication operator. One of the goals of each telecommunications vendor is to produce equipment and software in such a way as to reduce the risk of successful attacks upon networks built using their equipment and software. This master’s thesis aims to identify the classes of attacks that could affect the regular operation of an IPsec-protected network. Therefore, the IPsec protocol and its possible weaknesses are explained. As practical demonstration of these ideas, an Intrusion Detection Analyzer prototype for an Ericsson Ethernet Interface board was developed to detect anomalous IPsec-protected traffic. / IP Security (IPsec) protokollet används bl.a. för att skydda Virtuellt Privat Nätverk (VPN). Protokollet används även för att skydda noderna i tredje generationens (3G) mobila nätverk. Telekomoperatöreranas uppgift går bl.a. ut på att se till att de mobila näten är tillgängliga för användarna samt garanterna en viss garanterad tjänstekvalitet. Därför är kunskapen om de olika hoten som påverkar dessa faktorer relevant. Överbelastningsattacker och andra attacker kan utgöra ett stort hot mot bl.a. 3G nät. Om dessa attacker lyckas kan de leda till finansiella skador och ett skadat anseende för telekomoperatörerna. Ett av målen för telekomtillverkarna är att tillverka produkter och program som kan minimera riskerna för en attack och skadorna som åstadkoms på ett nätverk uppbyggt med deras utrustning. Detta examensarbete har som mål att identifiera de olika typer av attacker som kan påverka driften av IPsec-skyddade nätverk. IPsecprotokollet och dess svagheter är förklarade. Svagheter och problem med vissa implementationer nämns också. I detta arbete ingår också att utveckla en Intrusion Detection Analyzer prototyp för ett Ericssons Ethernet Gränssnitt kort för att upptäcka avvikande IPsecskyddad trafik

Software radios have evolved as multimode, programmable digital radios that perform radio functions using digital signal processing algorithms. They have been designed as software programmable radios using a combination of various hardware elements and structures. In this dissertation a {em{soft radio}} refers to a completely configurable radio that can be programmed through software, to change the radio behavior including the hardware functionality. Conventional software radios achieve flexibility through software with the use of static hardware. While these radios have the flexibility to operate in multiple modes, the hardware is not used efficiently. This inefficient utilization of hardware frequently limits the flexibility of software radios and the number of modes the radio can support. Soft radios however, attempt to gain flexibility through the use of reconfigurable hardware. The same piece of hardware can be configured to perform different functions based on the mode the radio is operating in. While many soft/software radio architectures have been suggested and implemented, there remains a lack of a formal design methodology that can be used to design and implement reconfigurable soft radios. Most designs are based on ad hoc approaches which are appropriate only for the problem at hand. After examining the design issues of a soft radio an architecture, called the {em{Layered Radio Architecture}}, is developed with the use of stream based processing and run-time reconfigurable hardware. These choices aid in maximizing performance with minimum hardware while keeping the architecture robust, simple, and scalable. The reconfigurable platform enables {em hardware paging} through reusability hardware. The stream-based approach gives a uniform modular structure to the processing modules and defines the protocol for interaction between various modules. The architecture describes a formal yet open design methodology and makes it possible to incorporate all of the features of a software radio while minimizing complexity issues. The layered architecture also defines the methodology for incorporating changes and updates into the system. The layered radio architecture assumes run-time reconfigurability of the hardware. This feature is not supported by existing commercial reconfigurable hardware, like FPGAs. An Custom Computing Machine (CCM), called Stallion that supports fast run time reconfiguration, has been developed at Virginia Tech. This dissertation describes the deficiencies of existing commercial reconfigurable hardware and shows how the Stallion is capable of supporting the layered radio architecture. The dissertation presents algorithms and procedures that can be used to implement the layered radio architecture using existing hardware. The architecture is validated with the implementation of two receivers: A single user CDMA receiver based on complex adaptive filtering and a W-CDMA downlink rake receiver with channel estimation. Performance analysis of these receivers show that it is important to keep the paging ratio high while maximizing utilization of the processing elements. The layered radio architecture with the use of Stallion can support existing high data rate systems. / Ph. D.

Even if 3rd and 4th generation wireless systems aim to achieve multimedia services at high speed, it is rather difficult to have full-fledged multimedia services due to insufficient capacity of the systems. There are many technical challenges placed on us in order to realize the real multimedia services. One of those challenges is how efficiently to allocate resources to traffic as the wireless systems evolve. The review of the literature shows that strategic manipulation of traffic can lead to an efficient use of resources in both wire-line and wireless networks. This aspect brings our attention to the role of link layer protocols, which is to orchestrate the transmission of packets in an efficient way using given resources. Therefore, the Media Access Control (MAC) layer plays a very important role in this context. In this research, we investigate technical challenges involving resource control and management in the design of MAC protocols based on the characteristics of traffic, and provide some strategies to solve those challenges. The first and foremost matter in wireless MAC protocol research is to choose the type of multiple access schemes. Each scheme has advantages and disadvantages. We choose Wireless Code Division Multiple Access/Time Division Duplexing (WCDMA/TDD) systems since they are known to be efficient for bursty traffic. Most existing MAC protocols developed for WCDMA/TDD systems are interested in the performance of a unidirectional link, in particular in the uplink, assuming that the number of slots for each link is fixed a priori. That ignores the dynamic aspect of TDD systems. We believe that adaptive dynamic slot allocation can bring further benefits in terms of efficient resource management. Meanwhile, this adaptive slot allocation issue has been dealt with from a completely different angle. Related research works are focused on the adaptive slot allocation to minimize inter-cell interference under multi-cell environments. We believe that these two issues need to be handled together in order to enhance the performance of MAC protocols, and thus embark upon a study on the adaptive dynamic slot allocation for the MAC protocol. This research starts from the examination of key factors that affect the adaptive allocation strategy. Through the review of the literature, we conclude that traffic characterization can be an essential component for this research to achieve efficient resource control and management. So we identify appropriate traffic characteristics and metrics. The volume and burstiness of traffic are chosen as the characteristics for our adaptive dynamic slot allocation. Based on this examination, we propose four major adaptive dynamic slot allocation strategies: (i) a strategy based on the estimation of burstiness of traffic, (ii) a strategy based on the estimation of volume and burstiness of traffic, (iii) a strategy based on the parameter estimation of a distribution of traffic, and (iv) a strategy based on the exploitation of physical layer information. The first method estimates the burstiness in both links and assigns the number of slots for each link according to a ratio of these two estimates. The second method estimates the burstiness and volume of traffic in both links and assigns the number of slots for each link according to a ratio of weighted volumes in each link, where the weights are driven by the estimated burstiness in each link. For the estimation of burstiness, we propose a new burstiness measure that is based on a ratio between peak and median volume of traffic. This burstiness measure requires the determination of an observation window, with which the median and the peak are measured. We propose a dynamic method for the selection of the observation window, making use of statistical characteristics of traffic: Autocorrelation Function (ACF) and Partial ACF (PACF). For the third method, we develop several estimators to estimate the parameters of a traffic distribution and suggest two new slot allocation methods based on the estimated parameters. The last method exploits physical layer information as another way of allocating slot to enhance the performance of the system. The performance of our proposed strategies is evaluated in various scenarios. Major simulations are categorized as: simulation on data traffic, simulation on combined voice and data traffic, simulation on real trace data. The performance of each strategy is evaluated in terms of throughput and packet drop ratio. In addition, we consider the frequency of slot changes to assess the performance in terms of control overhead. We expect that this research work will add to the state of the knowledge in the field of link-layer protocol research for WCDMA/TDD systems. / Ph. D.

O crescente aumento da demanda de tráfego nas redes celulares vem aumentando a necessidade de uma melhor utilização dos recursos do sistema, já que sua expansão é custosa. Nas estações rádio base (ERB), a disponibilidade de largura de faixa de freqüências é limitada e desta maneira, em uma rede de comunicação móvel celular, o controle de admissão de chamadas exerce grande influência no desempenho do sistema, pois determina a utilização de banda das ERBs e se uma determinada quantidade de recursos (banda) será alocado ou não para uma determinada chamada. O desempenho da rede pode ser atrelado a determinados parâmetros, como a probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de chamadas handoff e a utilização de banda da rede. Este trabalho propõe um controle de admissão de chamadas que, no atendimento de uma chamada, faz o empréstimo de banda de chamadas em andamento na célula no caso de banda insuficiente. O sistema adota um mecanismo heurístico que determina a banda disponível para novas chamadas conforme os valores de certos parâmetros do sistema. O empréstimo de banda é realizado em chamadas em andamento nas células até níveis mínimos estabelecidos para cada tipo de chamada, que se diferenciam pelas necessidades de banda de cada uma. O algoritmo foi aplicado às bandas e características de uma rede de terceira geração (3G), que possui chamadas de voz, videoconferência, interação multimídia, e-mail, downloads e transferência de arquivos e a uma rede GSM/GPRS (global system for mobile communications/ general packet radio service), que possui chamadas de voz e de dados. Os resultados mostram melhorias na probabilidade de bloqueio de novas chamadas, probabilidade de bloqueio de handoff e na utilização de banda do sistema. / The recent growth in traffic loads in cellular networks has seen the need for a better use of system resources as its expansion is expensive. In the base transceiver station (BTS), the bandwidth availability is limited. Thus, in cellular networks the call admission control greatly influences the system performance because it determines the bandwidth use of the BTSs and if an amount of resources will or will not be allocated to a call. The network performance can be evaluated by parameters such as blocking probability of new calls, dropping probability of handoff calls and bandwidth use. This work proposes a call admission control that carries out the bandwidth borrowing when a call arrives and there is not enough bandwidth. The system makes use of a heuristic mechanism that determines the available bandwidth for the new calls according to some parameter values of the system. The bandwidth borrowing is applied to the cell ongoing calls until the minimum levels for each type are met. The algorithm was applied to the bandwidths and characteristics of a third generation cellular network, which supports voice calls, videoconference, multimedia interaction, e-mails, downloads and file transfers. It was also applied to a GSM/GPRS (global system for mobile communications/ general packet radio service), which supports voice and data calls. The results show improvements in the blocking probability of new calls, dropping probability of handoff calls and in the bandwidth use of the system.