Dissertations / Theses on the topic 'Broadband and LTE'

COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
FUNDAÇÃO DE APOIO À PESQUISA DO ESTADO DO RIO DE JANEIRO
Atualmente, as redes celulares estão sendo utilizadas como uma saída para prover serviços de banda larga em locais que ainda não são atendidos pelas redes fixas, principalmente em países subdesenvolvidos como o Brasil. As tecnologias empregadas atualmente no Brasil, o GSM (Global System for Mobile) e o UMTS (Universal Mobile Telecommunications System), não são tecnologias desenvolvidas para absorver a grande demanda que vem sendo observada no mercado de banda larga móvel. Devido a essa demanda inesperada, acredita-se que o LTE (Long Term Evolution), a primeira tecnologia desenvolvida com o objetivo de atender não somente as chamadas de voz, mas principalmente as conexões banda larga, apresente condições de suportar com maior eficiência esta crescente necessidade. Para que todas as expectativas relacionadas à capacidade das redes LTE sejam atendidas, é extremamente necessário que um correto dimensionamento dessas redes seja realizado, pois somente desta forma será possível estabelecer o compromisso de se atender os usuários com qualidade.
At the moment, the cellular networks are being used as an option to provide broadband services in places that have not yet been covered by the fixed networks, mainly in underdeveloped countries like Brazil. The employed technologies now in Brazil, GSM (Global System is Mobile) and UMTS (Mobile Universal Telecommunications System), they were not developed to absorb the great demand that has been observed at the broadband mobile market. Due to that unexpected demand, it’s being believed that LTE (Long Term Evolution), the first technology developed with the objective of supporting not only the voice calls, but mainly the broadband connections, is able to hold with larger efficiency this growing needs. For all that expectations about the LTE network’s capacity be achieved, it is extremely necessary that a correct sizing of those networks be accomplished, therefore only this way it will be possible to establish the commitment of supporting the subscribers with quality.

The mobile broadband services have developed rapidly over the years, becoming critical revenue components of operator business. To accommodate users' growing interests on mobile broadband services and applications, global operators have tried to reorganize their former voice-centered networks by focusing more on the reinforcement of mobile data network performances and capacities. TD-LTE, as one of the emerging powers for the mobile broadband solutions, has gained global attentions and momentums. Different from previous work about the technical evaluations or market predictions, the thesis aims to provide a techno-economic analysis to TD-LTE system, linking its technological characters to the market opportunities and implementation strategies. In order to help TD-LTE operators identify the profit potentials of the system, the services and applications that TD-LTE could enable are discussed together with the analysis of the terminal developments, which are critical to end users' acceptance of TD-LTE. The network deployment strategies are examined and the methods of implementing a decent TD-LTE mobile data network are analyzed with cost efficiency considerations. The analysis find out that the availability of spectrum resource are of most importance for the adoption of TD-LTE technology and the sustainable growth of TD-LTE business relies on the differentiation strategy of services and applications. The feasibility study shows that TD-LTE could enable varied network deployment scenarios, including integrated network solution with legacy networks, and convergent network solution with LTE FDD. The cost analysis find out site infrastructure sharing is beneficial for cost reduction during a national level rollout, especially when the traffic volume increases. Reusing the coverage and capacity of legacy network is mostly effective in the initial phase, and TD-LTE deployment pace should accord with the data prediction on the live network. For compact and indoor scenarios, TD-LTE femto could be a cost effective alternative for mobile broadband access, however the bottleneck of the solution is the limitation on the number of concurrent connections for each femtocell.

Future generation cellular networks are expected to deliver an omnipresent broadband access network for an endlessly increasing number of subscribers. Long term Evolution (LTE) represents a significant milestone towards wireless networks known as 4G cellular networks. A key feature of LTE is the implementation of enhanced Radio Resource Management (RRM) mechanism to improve the system performance. The structure of LTE networks was simplified by diminishing the number of the nodes of the core network. Also, the design of the radio protocol architecture is quite unique. In order to achieve high data rate in LTE, 3rd Generation Partnership Project (3GPP) has selected Orthogonal Frequency Division Multiplexing (OFDM) as an appropriate scheme in terms of downlinks. However, the proper scheme for an uplink is the Single-Carrier Frequency Domain Multiple Access due to the peak-to-average-power-ratio (PAPR) constraint. LTE packet scheduling plays a primary role as part of RRM to improve the system’s data rate as well as supporting various QoS requirements of mobile services. The major function of the LTE packet scheduler is to assign Physical Resource Blocks (PRBs) to mobile User Equipment (UE). In our work, we formed a proposed packet scheduler algorithm. The proposed scheduler algorithm acts based on the number of UEs attached to the eNodeB. To evaluate the proposed scheduler algorithm, we assumed two different scenarios based on a number of UEs. When the number of UE is lower than the number of PRBs, the UEs with highest Channel Quality Indicator (CQI) will be assigned PRBs. Otherwise, the scheduler will assign PRBs based on a given proportional fairness metric. The eNodeB’s throughput is increased when the proposed algorithm was implemented.

Останнім часом бурхливими темпами розвиваються мобільні технології зв’язку. Доказом є те, що в Україні 6 березня 2018 року за сприяння президента України Петра Олексійовича Порошенка представники трьох провідних українських мобільних операторів Київстар, Vodafone-Україна та Lifecell одержали три ліцензії за право на зв'язок 4 покоління.

In order to keep up with the increasing demand on speed and reliability in modern wireless systems, new standards have to be introduced. By using Multiple Input Multiple Output technology (MIMO) and Orthogonal Frequency Division Multiplexing (OFDM) technologies the performance can be increased dramatically. Forthcoming standards such as WLAN 802.11n, WiMax and 3GPP LTE are all taking advantage of MIMO technology. To perform realistic tests with these standards it is often not enough to run software simulations in for example Matlab. Instead, as many real world parameters as possible need to be included. This can be done using a testbed, like the LiUMIMO, that actually transmits and receives data through the air.

The LiUMIMO is designed as a Software Defined Radio (SDR), only the RF front end and the data log are implemented in hardware, while all signal processing will be performed in Matlab.

In the last 45 years, the Sultanate of Oman has developed overdramatically and steadily in all aspects of life. This progress has included health, education and transportation sectors along with social and economic areas. The progress has also counted in the telecommunication services with many new land and wireless networks such as fibre optic networks, 3G, 4G/LTE and WiMAX. These telecommunication services have covered major cities and towns in the country, but due to the vast and inhospitable terrains of Oman with its geographical, demographical and social factors, it has been very problematic to cover major rural and urban areas of the country with satisfactory fibre and mobile services for home and mobile users by using one of the current traditional fixed and mobile technologies. Therefore, in this research, we have investigated the feasibility of using Television White Space (TVWS) technology in providing the required internet service by combining it with the ever-evolving Long Term Evolution- Advanced (LTE-A) technology as a solution to the problem mentioned above. For this purpose, and to specify the occupancy of the TVWS spectrum so to suggest a solution based on the LTE-A operating on the TVWS, we have conducted a radio spectrum occupancy measurement survey campaign for 40 MHz to 2800 MHz range. The survey was conducted in five major areas of the country. The campaign has identified that the TV spectrum (470 MHz to 890 MHZ) is idle most of the time. Further, we have implemented our proposed solution through the simulation of the Long-Term Evolution-Advanced (LTE-A) Ver. 12 technology operating in the TV spectrum (470-710 MHz). This type of solution is the first to use Ver. 12 on TVWS even on a simulation level. The simulation approach has been chosen over a real implementation because the technology is still in its early development stage, therefore, the hardware required for the implementation is still out of reach. Our simulation involved planning and implementation of two networks with eight scenarios. One network is our proposed network and the other is the classical LTE network operating on the 1800 MHz spectrum. The simulation results and analysis have demonstrated that our solution could provide reliable mobile and fixed service to a large number of users in a very large area with high data throughput and good Quality of Service (QoS) by using very little resources such as sites, Base Stations (BSs) and other resources. The simulation has demonstrated that one TVWS Base Station (TVWSBS) could cover up to 110 Km radius area and provide up to 4 Gigabits Per Second (4Gbps) DownLink (DL) and up to 2 Gbps UpLink (UL) data throughput. Therefore, our solution overweighs the traditional LTE/4G network in all aspects. This type of technology could meet the needs of broadband internet service for rural and congested areas of Oman using most of the existing old TV towers infrastructure and with minimum investment. Therefore, in our research, we are proposing an alternative method of providing broadband internet service that differs from the available traditional methods found in the literature considering the unique particularities of the demographic, geographic, social and environmental factors of Oman. Additionally, we have outlined TVWS regulations that could be utilised by concerned spectrum authorities in Oman and similar countries. Finally, we have developed an algorithm that could manage TVWS Database (TVWSDB) and could be incorporated in the Service Providers’ (SP) network management systems.

One of the challenges of the mobile industry is to cope with the growth of mobile traffic demand expected for the next years, primarily driven by the increasing usage of mobile video services. Indeed, the existence of increasingly powerful terminals is encouraging the consumption of high-quality video content. Usually, video services are identified with linear Television (TV) and scheduled broadcast (point-to-multipoint (p-t-m)) distribution. However, the consumption of video content over mobile networks is different from traditional fixed TV because contents are mainly consumed on-demand with unicast point-to-point (p-t-p) connections. Then, the convergence of linear TV and on-demand content delivery represents a challenge that requires a combined broadcast/unicast transmission model. This dissertation addresses the use of broadcasting technologies for the provision of mobile multimedia services in Fourth Generation (4G) mobile broadband networks and beyond. Specifically, the dissertation focuses on the broadcast technology included in 4G Long Term Evolution (LTE) and LTE Advanced (LTE-A) networks, known as Enhanced Multicast Broadcast Multimedia Services (eMBMS). It analyses the benefits of the eMBMS physical layer aspects regarding Multimedia Broadcast Multicast Services over a Single Frequency Network (MBSFN) deployments and identifies the current limitations of eMBMS at physical layer by comparing with the broadcast technology of the other 4G mobile system, the Institute of Electrical and Electronics Engineers (IEEE) 802.16m standard. Those limitations are the use of a dedicated carrier and Multiple-Input Multiple-Output (MIMO) techniques for broadcast transmissions. Our investigations employ a complete simulation platform including link-level and system-level simulations to evaluate the performance of broadcast transmissions in these real technologies. The research on eMBMS services is aimed at finding the optimum delivery of streaming and file download services focusing on the Radio Resource Management (RRM) problem and trade-off between Physical layer – Forward Error Correction (PHY-FEC) and Application Layer - Forward Error Correction (AL-FEC). Concerning streaming services, results show that the use of AL-FEC increases the coverage level and, then, the maximum service data rate. The gain due to AL-FEC is greater in scenarios with high mobility users, although, this gain is limited if low zapping times are desired. Regarding file delivery services, this dissertation analyses the duration of the transmission required to guarantee the correct file reception and the reduction in the mean throughput of unicast users with different delivery modes. They are the unicast delivery, the eMBMS delivery and a hybrid approach, which combines a first eMBMS delivery with a postdelivery error repair phase with unicast transmissions. Our results show that the hybrid delivery is the most efficient configuration in terms of file download time, although it further reduces unicast performance.
Calabuig Gaspar, J. (2015). Broadcasting in 4G mobile broadband networks and its evolution towards 5G [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/48561
TESIS

Digital front-end and Turbo decoder are the two key components in the digital wireless communication system. This thesis will discuss the implementation issues of both digital front-end and Turbo decoder.The structure of digital front-end for multi-standard radio supporting wireless standards such as IEEE802.11n, WiMAX, 3GPP LTE is investigated in the thesis. A top-to-down design methods. 802.11n digital down-converter is designed from Matlab model to VHDL implementation. Both simulation and FPGA prototyping are carried out.As another significant part of the thesis, a parallel Turbo decoder is designed and implemented for 3GPPLTE. The block size supported ranges from 40 to 6144 and the maximum number of iteration is eight.The Turbo decoder will use eight parallel SISO units to reach a throughput up to 150Mits.

In advanced wireless communication systems, a rapid increase in the mobile data traffic and broad information bandwidth requirement can lead to the use of complex spectrally efficient modulation schemes such as orthogonal frequency-division multiplexing (OFDM). Generally, complex non-constant envelope modulated signals have very high peak-to-average ratios (PAPR). Doherty Power Amplifier (DPA) is the most commonly used power amplifier (PA) architecture for meeting high efficiency requirement in advanced communication systems, in the presence of high PAPR signals. However, limited bandwidth of the conventional DPA is often identified as a bottleneck for widespread deployment in base-station application for multi-standard communication signals. The research in this thesis focuses on the development of new designs to overcome the bandwidth limitations of a conventional PA. In particular, the bandwidth limitation factors of a conventional DPA architecture are studied. Moreover, a novel design technique is proposed for DPA’s bandwidth extension. In the first PA design, limited bandwidth and linearity problems are addressed simultaneously. For this purpose, a new Class-AB PA with extended bandwidth and improved linearity is presented for LTE 5 W pico-cell base-station over a frequency range of 1.9–2.5 GHz. A two-tone load/source-pull and bias point optimization techniques are used to extract the sweet spots for optimum efficiency and linearity from the 6 W Cree GaN HEMT device for the whole frequency band. The realized prototype presented saturated PAE higher than 60%, a power gain of 13 dB and an average output power of 36.5 dBm over the desired bandwidth. The proposed PA is also characterized by QAM-256 and LTE input communication signals for linearity characterization. Measured ACPRs are lower than -40 dBc for an input power of 17 dBm. The documented results indicate that the proposed Class-AB architecture is suitable for pico-cell base-station application. In the second PA design, an inherent bandwidth limitation of Class-F power amplifier forced by the improper load harmonics terminations at multiple harmonics is investigated and analyzed. It is demonstrated that the impedance tuning of the second and third harmonics at the drain terminal of a transistor is crucial to achieve a broadband performance. The effect of harmonics terminations on power amplifier’s bandwidth up to fourth harmonics is investigated. The implemented broadband Class-F PA achieved maximum saturated drain efficiency 60-77%, and 10 W output power throughout (1.1-2.1 GHz) band. The simulated and measured results verify that the presented Class-F PA is suitable for a high-efficiency system application in wireless communications over a wide range of frequencies. In the third PA design, a single- and dual-input DPA for LTE application in the 3.5 GHz frequency band are presented and compared. The main goal of this study is to improve the performance of gallium–nitride (GaN) Doherty transmitters over a wide bandwidth in the 3.5 GHz frequency band. For this purpose, the linearity-efficiency trade-off for the two proposed architectures is discussed in detail. Simulated results demonstrate that the single- and dual-input DPA exhibited a peak drain efficiency (DE) of 72.4% and 77%, respectively. Both the circuits showed saturated output power more than 42.9 dBm throughout the designed band. Saturated efficiency, gain and bandwidth of dual-input DPA are higher than that of the single-input DPA. On the other side, dual-input DPA linearity is worse as compared to the single-input DPA. In the last PA design, a novel design methodology for ultra-wide band DPA is presented. The bandwidth limitation factors of the conventional Doherty amplifier are discussed on the ground of broadband matching with impedance variation. To extend the DPA bandwidth, three different methods are used such as post-matching, low impedance transformation ratio and the optimization of offset line for wide bandwidth in the proposed design. The proposed Doherty power amplifier was designed and realized based on two 10 W GaN HEMT devices from Cree Inc. The measured results exhibited 42-57% of efficiency at the 6-dB back-off and saturated output power ranges from 41.5 to 43.1 dBm in the frequency range of 1.15 to 2.35 GHz (68.5% fractional bandwidth). Moreover, less than -25 dBc ACPRs are measured at 42 dBm peak output power throughout the designed band. In a nutshell, all power amplifiers presented in this thesis are suitable for wideband operation and their performances are satisfying the required operational standard. Therefore, this thesis has a significant contribution in the domain of high efficiency and broadband power amplifiers.

Abstract Sharing is emerging as one of the megatrends influencing future business opportunities, and wireless communications is no exception to this development. Future mobile broadband networks will operate on different types of spectrum bands including shared spectrum, which calls for changes in the operation and management of the networks. The creation and capture of value by the different players in the mobile broadband ecosystem is expected to change due to regulation, technology, and business landscape related drivers that concern not only spectrum sharing, but also sharing of other resources such as infrastructure, technologies, or data. This thesis examines the key business and technology enablers needed to exploit spectrum sharing in mobile broadband networks, and presents the business model characteristics and strategic choices that spectrum sharing concepts support. Action research and integral scenarios methodologies were applied for strategic and business analysis utilizing the capacity and expertise of the policy, business and technology research communities. The thesis introduces a new approach to analyze the scalability of the spectrum sharing concepts and their business model elements utilizing sharing economy antecedent factors. The results indicate that all analyzed sharing concepts meet basic requirements to scale. The Licensed Shared Access (LSA) leverages existing assets and capabilities of the mobile network operator domain, the Citizens Broadband Radio Service (CBRS) extends the business model dynamics from connectivity to content, context and commerce, and the hybrid usage of Ultra High Frequency (UHF) band by Digital Terrestrial TV (DTT) and downlink Long Term Evolution (LTE) (HUHF) enables new collaborative opportunities between converging communication, Internet and media domains. The thesis validates the feasibility of spectrum sharing between mobile broadband networks and other types of incumbent spectrum users utilizing Finnish cognitive radio field trial environment (CORE), and expands the notion of spectrum sharing beyond the mobile broadband domain to be applied to other wireless systems including the media and broadcasting. The presented results can be used in developing the future mobile broadband systems enhanced with innovative spectrum sharing enabled business models to cope with the growing demand for capacity and new services by humans and machines
Tiivistelmä Jakamistalous on yksi suurista tulevaisuuden liiketoimintamahdollisuuksiin vaikuttavista trendeistä, eikä langaton tietoliikenne ole tässä poikkeus. Tulevaisuuden laajakaistaiset matkapuhelinverkot tulevat hyödyntämään erityyppisiä radiotaajuuksia, kuten jaettuja taajuuskaistoja, mikä vaatii muutoksia verkkojen toimintoihin ja hallintaan. Eri toimijoiden arvonluonti- ja ansaintamahdollisuuksien odotetaan muuttuvan näissä liikkuvan laajakaistan ekosysteemeissä regulaation, teknologian ja liiketoimintaympäristön kehittyessä, ei vain taajuuksien jakamisessa, vaan myös kun kyseessä on muiden resurssien kuten infrastruktuurin, teknologioiden tai tiedon jakaminen. Väitöskirja tutkii teknologia- ja liiketoimintaedellytyksiä taajuusjakomenetelmille matkapuhelinverkoissa, sekä esittelee ja analysoi menetelmien mahdollistamia liiketoimintamalleja ja strategisia valintoja. Strategia- ja liiketoiminta-analyyseissä käytettiin toimintatutkimus- ja skenaariomenetelmiä poikkitieteellisissä tutkimusprojekteissa yhteistyössä reguloinnin, liiketoiminnan ja tekniikan tutkimusyhteisöjen kanssa. Tutkimus esittelee uuden lähestymistavan taajuusjakotekniikoiden liiketoimintamallien skaalautuvuuden analysointiin jakamistalouden määritelmiä hyödyntäen. Tulokset osoittavat, että kaikki tutkitut tekniikat täyttävät perusedellytykset skaalautuvuudelle; Licensed Shared Access (LSA) hyödyntäen matkapuhelinoperaattorin olemassa olevia resursseja ja kyvykkyyksiä, Citizens Broadband Radio Service (CBRS) laajentaen liiketoimintamalleja tietoliikenteestä sisältöön, kontekstiin ja kaupankäyntialustoihin, sekä digitaalitelevision ja langattoman LTE-tekniikan hybridikäyttö UHF-taajuuskaistalla (HUHF) mahdollistaen uusia liiketoimintamahdollisuuksia lähentyvien tietoliikenne-, Internet- ja mediaekosysteemien välillä. Väitöskirja tulokset vahvistivat taajuuden jakamisen soveltuvuuden liikkuvan laajakaistaverkon ja saman taajuusalueen eri teollisuudenalan haltijan välillä suomalaisessa CORE kenttätestausympäristössä, ja laajensivat taajuusjakotekniikan sovellettavuutta myös muihin langattomiin järjestelmiin sisältö- ja mediajakelussa. Esitettyjä tuloksia voidaan hyödyntää tulevaisuuden langattomien laajakaistaverkkojen kehitystyössä vastaamaan ihmisten ja koneiden kasvaviin tietoliikennepalveluiden ja -kapasiteetin tarpeisiin hyödyntäen tehokkaita taajuusjakotekniikoita ja niiden mahdollistamia innovatiivisia liiketoimintamalleja

Rapid convergence of heterogeneous wireless communication technologies such as Wireless Local Area Networks (WLAN), 4G: LTE/LTE-Advanced Mobile Broadband, 5G and Worldwide Interoperability for Microwave Access (WiMAX), attract new opportunities for ubiquitous connectivity enabling collaborative usage. Hence, it is predicted that the ever-increasing use of wireless Internet demands a significant increase in wireless broadband throughput. However, to maintain reliable and seamless connectivity wireless devices entail simultaneous multi-gateway connections. Therefore, emerging technologies should be capable of performing secure roaming between the diverse wireless networks. Nevertheless, vertical handover (roaming) and seamless connectivity involve overcoming not only the incompatibility issues between the different wireless technologies but also the incompatibility issues amongst the authentication mechanisms used in the various wireless networks. For seamless connectivity, wireless devices need to authenticate in a timely fashion with the different types of wireless networks. However, the authentication mechanisms used in these wireless networks can be specific and fitting only to those wireless technologies. Hence, roaming becomes a major challenge due to the incompatible authentication mechanisms, parameters and credentials. Further, users demand a single but unique set of credentials to authenticate the wireless devices in the heterogeneous wireless environment. In other words, future heterogeneous networks demand a coordinated authentication mechanism for vertical handover with the ability to use a single but unique set of credentials enabling secure and fast roaming.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Information and Communication Technology
Science, Environment, Engineering and Technology
Full Text

The theme of the thesis is an analysis of current mobile operator selected services. This work focuses on the present and the future development of mobile internet connection. The aim is to analyze existing services at Telefónica Czech Republic and The work is divided into several parts. The first part focuses on the selection of a particular operator. I described at al. Czech Republic and Telefónica, which is the first integrated operator in the Czech Republic. The company currently operates more than seven million mobile numbers and fixed lines, making it one of the leading providers of fully converged services in Europe. I focused on the organizational structure of the company and its description. The second part is historical, describes the history of mobile networks in the CR, the history of mobile communications in the data and the development of mobile connections in the country. The third part is theoretical, describes al. Czech Republic Telefonica SpA in terms of services it offers in this section is also described ISO certification, EMS policy and business principles. Are described voice and mobile services, mobile data services and connectivity technologies and different types of technologies (GSM, GPRS, EDGE, UMTS, HSDPA, HSPA + and LTE). Another section includes the development of mobile connections in the CR, the current situation where Telefónica provides 3G connection for almost 71% of the population and the current state of commercial LTE network. I tried to describe the current mobile platforms, and even telecommunications market in the Czech Republic. The penultimate section specifies the geographic traffic distribution network operator and the last part, I dealt with the analysis and comparison services. The total contribution of the thesis see the approach and evaluation of existing services together. Telefónica Czech Republic, as, which is one of the largest telecommunications companies in the world.

Doutoramento em Engenharia Eletrónica
This thesis addresses the issue of Universal Service for telecommunications in the context of the access networks of next generation. This work aims to contribute to the redefinition of the concept of universal telecommunications service focusing primarily on extending it to broadband services as economic and social development factor and taking into account the degree of dependence that currently, modern societies have for the different communication and information services. Complementarily it also intended to meet some of the challenges set out in the European 2020 agenda. Universal Service is defined here as access to a telecommunications network (with obligations in terms of type and quality of service for the operator), by of all citizens at any country's geographical location, with uniform and accessible price. The approach adopted is the State as a mentor for social equity, respectful of the liberalized market dynamics but also knowledgeable of the requirements of modern telecommunications services and its relationship with the different technologies available. The possibility of subsidizing is assumed. The Universal Service´s provision is subject to open to all operators, which are assumed to possess other profitability businesses, than the Universal Service, using technologies similar to those prescribed for the respective Universal Service provision contest. Although the work has components of economic and financial analysis, the approach is the engineering point of view, looking for help to identify technical and organizational solutions which offer prospects for the dissemination and adoption of next generation network solutions. As a point of departure the work gives an overview on the state of the art access networks , trying to identify which of the differences between this reality and possible scenarios for next-generation network with potential access to the generality of the people . The case of the Portuguese reality will be given special attention, taking into account their specific characteristics in terms of geography, demography, economics and market dynamics. The main results of this work are: • Identification of possible scenarios for the evolution of existing networks, in particular in areas with deficit coverage. • Identification of possible operating models and business to the materialization of the above scenarios developed and its economic analysis in an attempt to determine the critical factors associated with sustainability and / or need for subsidies. • Contribution to the regulatory framework of new generation networks from the point of view of the constraints of technology and the specifics of the Universal Service.
Esta tese aborda a questão do serviço universal de telecomunicações no contexto das redes de acesso de nova geração. Este trabalho pretende contribuir para a redefinição do conceito de Serviço Universal de Telecomunicações concentrando-se principalmente em estendê-lo a serviços de banda larga como factor de desenvolvimento económico e social e tendo em conta o grau de dependência que, actualmente, as sociedades modernas têm em relação aos diferentes serviços de comunicação e informação. De forma complementar pretende-se também ir ao encontro de alguns dos desafios enunciados na Agenda Europeia 2020. Serviço Universal é aqui definido como o acesso a uma rede de telecomunicações (com obrigações em termos de tipo e qualidade de serviço para o operador), por parte de todos os cidadãos, em qualquer localização geográfica do país, a preços uniformes e acessíveis. A perspectiva adoptada é a Estatal como mentor da equidade social, respeitador das dinâmicas de mercado liberalizado mas também conhecedor dos requisitos dos modernos serviços de telecomunicações e da sua relação com as diferentes tecnologias disponíveis. A possibilidade de subsidiação é assumida. A prestação de Serviço Universal é sujeita a concurso aberto a todos os operadores, que se assume possuírem outros negócios, que não apenas o Serviço Universal, com rentabilidade e usando tecnologias semelhantes às preconizadas para a respectiva prestação de Serviço Universal. Embora o trabalho desenvolvido tenha componentes de análise económico-financeira, a abordagem utilizada é a de engenharia, procurando contribuir para a identificação de soluções técnicas e organizacionais que possam oferecer perspectivas sustentáveis para a disseminação e adopção das soluções redes de nova geração. Como ponto de partida o trabalho apresenta uma visão geral sobre o estado da arte das redes de acesso, procurando identificar quais os diferenciais existentes entre essa realidade e a de possíveis cenários de rede de próxima geração com potencial de acesso para a generalidade dos cidadãos. O caso da realidade Portuguesa será objecto de uma atenção especial, tendo em consideração as suas especificidades em termos de geografia, demografia, economia e dinâmicas do mercado. Os principais resultados deste trabalho são os seguintes: • Identificação de possíveis cenários para a evolução das redes actuais, nomeadamente em áreas com deficit de cobertura de rede. • Identificação de possíveis modelos de operação e negócio para a materialização dos cenários acima desenvolvidos e respectiva análise económica, como tentativa de determinar os factores críticos associados à sua sustentabilidade e /ou necessidade de subsidiação. • Contributo para o quadro regulatório das Redes de Nova Geração sob o ponto de vista dos constrangimentos das tecnologias e das especificidades do Serviço Universal.

La quinta generación de redes móviles (5G) se encuentra a la vuelta de la esquina. Se espera provea de beneficios extraordinarios a la población y que resuelva la mayoría de los problemas de las redes 4G actuales. El éxito de 5G, cuya primera fase de estandarización ha sido completada, depende de tres pilares: comunicaciones tipo-máquina masivas, banda ancha móvil mejorada y comunicaciones ultra fiables y de baja latencia (mMTC, eMBB y URLLC, respectivamente). En esta tesis nos enfocamos en el primer pilar de 5G, mMTC, pero también proveemos una solución para lograr eMBB en escenarios de distribución masiva de contenidos. Específicamente, las principales contribuciones son en las áreas de: 1) soporte eficiente de mMTC en redes celulares; 2) acceso aleatorio para el reporte de eventos en redes inalámbricas de sensores (WSNs); y 3) cooperación para la distribución masiva de contenidos en redes celulares. En el apartado de mMTC en redes celulares, esta tesis provee un análisis profundo del desempeño del procedimiento de acceso aleatorio, que es la forma mediante la cual los dispositivos móviles acceden a la red. Estos análisis fueron inicialmente llevados a cabo por simulaciones y, posteriormente, por medio de un modelo analítico. Ambos modelos fueron desarrollados específicamente para este propósito e incluyen uno de los esquemas de control de acceso más prometedores: access class barring (ACB). Nuestro modelo es uno de los más precisos que se pueden encontrar en la literatura y el único que incorpora el esquema de ACB. Los resultados obtenidos por medio de este modelo y por simulación son claros: los accesos altamente sincronizados que ocurren en aplicaciones de mMTC pueden causar congestión severa en el canal de acceso. Por otro lado, también son claros en que esta congestión se puede prevenir con una adecuada configuración del ACB. Sin embargo, los parámetros de configuración del ACB deben ser continuamente adaptados a la intensidad de accesos para poder obtener un desempeño óptimo. En la tesis se propone una solución práctica a este problema en la forma de un esquema de configuración automática para el ACB; lo llamamos ACBC. Los resultados muestran que nuestro esquema puede lograr un desempeño muy cercano al óptimo sin importar la intensidad de los accesos. Asimismo, puede ser directamente implementado en redes celulares para soportar el tráfico mMTC, ya que ha sido diseñado teniendo en cuenta los estándares del 3GPP. Además de los análisis descritos anteriormente para redes celulares, se realiza un análisis general para aplicaciones de contadores inteligentes. Es decir, estudiamos un escenario de mMTC desde la perspectiva de las WSNs. Específicamente, desarrollamos un modelo híbrido para el análisis de desempeño y la optimización de protocolos de WSNs de acceso aleatorio y basados en cluster. Los resultados muestran la utilidad de escuchar el medio inalámbrico para minimizar el número de transmisiones y también de modificar las probabilidades de transmisión después de una colisión. En lo que respecta a eMBB, nos enfocamos en un escenario de distribución masiva de contenidos, en el que un mismo contenido es enviado de forma simultánea a un gran número de usuarios móviles. Este escenario es problemático, ya que las estaciones base de la red celular no cuentan con mecanismos eficientes de multicast o broadcast. Por lo tanto, la solución que se adopta comúnmente es la de replicar e contenido para cada uno de los usuarios que lo soliciten; está claro que esto es altamente ineficiente. Para resolver este problema, proponemos el uso de esquemas de network coding y de arquitecturas cooperativas llamadas nubes móviles. En concreto, desarrollamos un protocolo para la distribución masiva de contenidos, junto con un modelo analítico para su optimización. Los resultados demuestran que el modelo propuesto es simple y preciso, y que el protocolo puede reducir el con
La cinquena generació de xarxes mòbils (5G) es troba molt a la vora. S'espera que proveïsca de beneficis extraordinaris a la població i que resolga la majoria dels problemes de les xarxes 4G actuals. L'èxit de 5G, per a la qual ja ha sigut completada la primera fase del qual d'estandardització, depén de tres pilars: comunicacions tipus-màquina massives, banda ampla mòbil millorada, i comunicacions ultra fiables i de baixa latència (mMTC, eMBB i URLLC, respectivament, per les seues sigles en anglés). En aquesta tesi ens enfoquem en el primer pilar de 5G, mMTC, però també proveïm una solució per a aconseguir eMBB en escenaris de distribució massiva de continguts. Específicament, les principals contribucions són en les àrees de: 1) suport eficient de mMTC en xarxes cel·lulars; 2) accés aleatori per al report d'esdeveniments en xarxes sense fils de sensors (WSNs); i 3) cooperació per a la distribució massiva de continguts en xarxes cel·lulars. En l'apartat de mMTC en xarxes cel·lulars, aquesta tesi realitza una anàlisi profunda de l'acompliment del procediment d'accés aleatori, que és la forma mitjançant la qual els dispositius mòbils accedeixen a la xarxa. Aquestes anàlisis van ser inicialment dutes per mitjà de simulacions i, posteriorment, per mitjà d'un model analític. Els models van ser desenvolupats específicament per a aquest propòsit i inclouen un dels esquemes de control d'accés més prometedors: el access class barring (ACB). El nostre model és un dels més precisos que es poden trobar i l'únic que incorpora l'esquema d'ACB. Els resultats obtinguts per mitjà d'aquest model i per simulació són clars: els accessos altament sincronitzats que ocorren en aplicacions de mMTC poden causar congestió severa en el canal d'accés. D'altra banda, també són clars en què aquesta congestió es pot previndre amb una adequada configuració de l'ACB. No obstant això, els paràmetres de configuració de l'ACB han de ser contínuament adaptats a la intensitat d'accessos per a poder obtindre unes prestacions òptimes. En la tesi es proposa una solució pràctica a aquest problema en la forma d'un esquema de configuració automàtica per a l'ACB; l'anomenem ACBC. Els resultats mostren que el nostre esquema pot aconseguir un acompliment molt proper a l'òptim sense importar la intensitat dels accessos. Així mateix, pot ser directament implementat en xarxes cel·lulars per a suportar el trànsit mMTC, ja que ha sigut dissenyat tenint en compte els estàndards del 3GPP. A més de les anàlisis descrites anteriorment per a xarxes cel·lulars, es realitza una anàlisi general per a aplicacions de comptadors intel·ligents. És a dir, estudiem un escenari de mMTC des de la perspectiva de les WSNs. Específicament, desenvolupem un model híbrid per a l'anàlisi de prestacions i l'optimització de protocols de WSNs d'accés aleatori i basats en clúster. Els resultats mostren la utilitat d'escoltar el mitjà sense fil per a minimitzar el nombre de transmissions i també de modificar les probabilitats de transmissió després d'una col·lisió. Pel que fa a eMBB, ens enfoquem en un escenari de distribució massiva de continguts, en el qual un mateix contingut és enviat de forma simultània a un gran nombre d'usuaris mòbils. Aquest escenari és problemàtic, ja que les estacions base de la xarxa cel·lular no compten amb mecanismes eficients de multicast o broadcast. Per tant, la solució que s'adopta comunament és la de replicar el contingut per a cadascun dels usuaris que ho sol·liciten; és clar que això és altament ineficient. Per a resoldre aquest problema, proposem l'ús d'esquemes de network coding i d'arquitectures cooperatives anomenades núvols mòbils. En concret, desenvolupem un protocol per a realitzar la distribució massiva de continguts de forma eficient, juntament amb un model analític per a la seua optimització. Els resultats demostren que el model proposat és simple i precís
The 5th generation (5G) of mobile networks is just around the corner. It is expected to bring extraordinary benefits to the population and to solve the majority of the problems of current 4th generation (4G) systems. The success of 5G, whose first phase of standardization has concluded, relies in three pillars that correspond to its main use cases: massive machine-type communication (mMTC), enhanced mobile broadband (eMBB), and ultra-reliable low latency communication (URLLC). This thesis mainly focuses on the first pillar of 5G: mMTC, but also provides a solution for the eMBB in massive content delivery scenarios. Specifically, its main contributions are in the areas of: 1) efficient support of mMTC in cellular networks; 2) random access (RA) event-reporting in wireless sensor networks (WSNs); and 3) cooperative massive content delivery in cellular networks. Regarding mMTC in cellular networks, this thesis provides a thorough performance analysis of the RA procedure (RAP), used by the mobile devices to switch from idle to connected mode. These analyses were first conducted by simulation and then by an analytical model; both of these were developed with this specific purpose and include one of the most promising access control schemes: the access class barring (ACB). To the best of our knowledge, this is one of the most accurate analytical models reported in the literature and the only one that incorporates the ACB scheme. Our results clearly show that the highly-synchronized accesses that occur in mMTC applications can lead to severe congestion. On the other hand, it is also clear that congestion can be prevented with an adequate configuration of the ACB scheme. However, the configuration parameters of the ACB scheme must be continuously adapted to the intensity of access attempts if an optimal performance is to be obtained. We developed a practical solution to this problem in the form of a scheme to automatically configure the ACB; we call it access class barring configuration (ACBC) scheme. The results show that our ACBC scheme leads to a near-optimal performance regardless of the intensity of access attempts. Furthermore, it can be directly implemented in 3rd Generation Partnership Project (3GPP) cellular systems to efficiently handle mMTC because it has been designed to comply with the 3GPP standards. In addition to the analyses described above for cellular networks, a general analysis for smart metering applications is performed. That is, we study an mMTC scenario from the perspective of event detection and reporting WSNs. Specifically, we provide a hybrid model for the performance analysis and optimization of cluster-based RA WSN protocols. Results showcase the utility of overhearing to minimize the number of packet transmissions, but also of the adaptation of transmission parameters after a collision occurs. Building on this, we are able to provide some guidelines that can drastically increase the performance of a wide range of RA protocols and systems in event reporting applications. Regarding eMBB, we focus on a massive content delivery scenario in which the exact same content is transmitted to a large number of mobile users simultaneously. Such a scenario may arise, for example, with video streaming services that offer a particularly popular content. This is a problematic scenario because cellular base stations have no efficient multicast or broadcast mechanisms. Hence, the traditional solution is to replicate the content for each requesting user, which is highly inefficient. To solve this problem, we propose the use of network coding (NC) schemes in combination with cooperative architectures named mobile clouds (MCs). Specifically, we develop a protocol for efficient massive content delivery, along with the analytical model for its optimization. Results show the proposed model is simple and accurate, and the protocol can lead to energy savings of up to 37 percent when compared to the traditional approach.
Leyva Mayorga, I. (2018). On reliable and energy efficient massive wireless communications: the road to 5G [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/115484
TESIS

Šiame darbe nagrinėjamos galimybės patobulinti plačiajuostės dielektrinės spektroskopijos metodus naudojant skaitmeninius ir analitinius daugelio modų dielektrinės skvarbos skaičiavimo metodus, tiriami (1-x)(Na1/2 Bi1/2)TiO3 - xLa(Mg1/2 Ti1/2)O3 (NBT-LMT) keramikų grupės laidumo ypatumai. Nagrinėjama galimybė pritaikyti HFSS skaitmeninio modeliavimo programą dielektrinės spektroskopijos tikslams. Naudojant šią programinę įrangą, apskaičiuojama dielektrinė ir magnetinė skvarbos komplikuotiems mikrojuostelinės linijos ir dalinai užpildyto bangolaidžio matavimo grandinių atvejams. Pateikiami patobulinti kondensatoriaus koaksialinėje linijoje ir ribotų matmenų atviro galo koaksialinės linijos matematiniai modeliai. Šie modeliai patikrinami skaitmeniniu metodu. Naudojant daugiamodį kondensatoriaus modelį, atsižvelgus į magnetinio lauko pasiskirstymą koaksialinėje matavimo grandinėje, pasiūlomas būdas pamatuoti mažai bandinio magnetinei skvarbai, kai dielektrinė skvarba didelė (dešimtim ar šimtais kartų didesnė už magnetinę skvarbą). Atviro galo koaksialinei linijai siūloma keletas kalibravimo būdų, įrenginys bandiniui prispausti prie linijos. Bešvinė NBT-LMT keramika buvo tyrinėjama dielektrinės spektroskopijos metodais. Gauti rezultatai rodo, kad NBT-LMT keramikų grupėje elektriniam laidumui galioja Maerio-Neldelio taisyklė.
Šiame darbe nagrinėjamos galimybės patobulinti plačiajuostės dielektrinės spektroskopijos metodus naudojant skaitmeninius ir analitinius daugelio modų dielektrinės skvarbos skaičiavimo metodus, tiriami (1-x)(Na1/2 Bi1/2)TiO3 - xLa(Mg1/2 Ti1/2)O3 (NBT-LMT) keramikų grupės laidumo ypatumai. Nagrinėjama galimybė pritaikyti HFSS skaitmeninio modeliavimo programą dielektrinės spektroskopijos tikslams. Naudojant šią programinę įrangą, apskaičiuojama dielektrinė ir magnetinė skvarbos komplikuotiems mikrojuostelinės linijos ir dalinai užpildyto bangolaidžio matavimo grandinių atvejams. Pateikiami patobulinti kondensatoriaus koaksialinėje linijoje ir ribotų matmenų atviro galo koaksialinės linijos matematiniai modeliai. Šie modeliai patikrinami skaitmeniniu metodu. Naudojant daugiamodį kondensatoriaus modelį, atsižvelgus į magnetinio lauko pasiskirstymą koaksialinėje matavimo grandinėje, pasiūlomas būdas pamatuoti mažai bandinio magnetinei skvarbai, kai dielektrinė skvarba didelė (dešimtim ar šimtais kartų didesnė už magnetinę skvarbą). Atviro galo koaksialinei linijai siūloma keletas kalibravimo būdų, įrenginys bandiniui prispausti prie linijos. Bešvinė NBT-LMT keramika buvo tyrinėjama dielektrinės spektroskopijos metodais. Gauti rezultatai rodo, kad NBT-LMT keramikų grupėje elektriniam laidumui galioja Maerio-Neldelio taisyklė.

Proteins—polymers of amino acids—are a major class of biomolecules whose myriad functions facilitate many crucial biological processes. Accordingly, human control over these biological processes depends upon the ability to study, produce, and modify proteins. One innovative tool for accomplishing these aims is cell-free protein synthesis (CFPS). This technique, rather than using living cells to make protein, simply extracts the cells' natural protein-making machinery and then uses it to produce protein in vitro. Because living cells are no longer involved, scientists can freely adapt the protein production environment in ways not otherwise possible. However, improved versatility and yield of CFPS protein production is still the subject of considerable research. This work focuses on two ideas for furthering that research.The first idea is the adaptation of CFPS to make proteins containing unnatural amino acids. Unnatural amino acids are not found in natural biological proteins; they are synthesized artificially to possess useful properties which are then conferred upon any protein made with them. However, current methods for incorporating unnatural amino acids do not allow incorporation of more than one type of unnatural amino acid into a single protein. This work helps lay the groundwork for the incorporation of different unnatural amino acid types into proteins. It does this by using modified aminoacyl-tRNA synthetases (aaRSs), which are key components in CFPS, to be compatible with unnatural amino acids. The second idea is the preservation of DNA templates from enzyme degradation in CFPS. Among the advantages of CFPS is the option of using linear expression templates (LETs) in place of plasmids as the DNA template for protein production. Because LETs can be produced more quickly than plasmids can, using LETs greatly reduces the time required to obtain a DNA template for protein production. This renders CFPS a better candidate for high-throughput testing of proteins. However, LETs are more susceptible to enzyme-mediated degradation than plasmids are, which means that LET-based CFPS protein yields are lower than plasmid-based CFPS yields. This work explores the possibility of increasing the protein yield of LET-based CFPS by addition of sacrificial DNA, DNA which is not used as a protein-making template but which is degraded by the enzymes in place of the LETs.

碩士
國立成功大學
電機工程學系碩博士班
101
The study of this thesis is LTE antenna designs for notebook application. The first design is a composite antenna design combining a planar inverted-F antenna and a monopole antenna, which can cover the WWAN band operation. The second design is to use two antennas to resonant lower band and higher band resonance modes separately. The design can cover the LTE band and have good radiation performance. The third design is an idea of antenna frequency band switching by adding a diode on antenna body. The antenna can cover the LTE band by switch lower frequency band and have a good performance.

碩士
國立高雄應用科技大學
電子工程系碩士班
103
In this thesis, three kinds of low profile and broadband planar monopole antennas are proposed for application to the LTE700/2300/2500 bands and wireless wide area network (WWAN) operation in the GSM850/900/DCS1800/PCS1900/UMTS bands. The first design uses a radiated monopole and extended strip line from the ground plane to produce a multimode operation for mobile phone application. The second design combines the modified monopole with shorted parasitic element to form a radiating structure. The third design utilizes the coupling effect between the modified G-shaped monopole and shorted meander to achieve a multiband operation and compact size. Above both designs are suitable for tablet computer application. The measured results show that the proposed antennas can apply in the LTE/WWAN bands.

碩士
國立交通大學
資訊科學與工程研究所
103
A system is defined to monitor and manage mobile broadband 4G LTE network. Network failure detection is the main function of this system. The network failures in mobile broadband network impact telecom services. It causes great loss to business. The current management systems used in the LTE network mostly deal with problems located in local domains. There are few systems used for monitoring the whole LTE network and evaluating network performance comprehensively. With the fast development of mobile broadband network and the increase of user requirements, the data transmission abilities and the capacities of network equipment are under great demand. Hence the comprehensive monitoring of LTE network is important to detect network failures and locate the fault node in a timely manner. This thesis research is based on the LTE network environment supported by Mobile Broadband Laboratory (BML) of National Chiao Tung University (NCTU). We designed and realized a system for LTE network failure detection. The system integrates traditional network management technology with LTE system architecture. It takes the network resources allocation into consideration to detect failure caused by unbalanced resource allocation and resource preemption.

碩士
南臺科技大學
電子工程系
107
Because of the signal transmission distance of the new generation mobile communication is short. In order to solve the problem of insufficient coverage of 4G mobile communication, this thesis proposes two broadband dual-polarized base stations antenna design for LTE and 5G C-band. These designs are operating at the frequency band of 4G mobile communication making up for the shortage of the new generation mobile communication signal coverage. The first dual-polarized antenna design for the LTE 2300 / LTE 2500 / WRC15 C-band (3.4 – 3.6 GHz) / China 5G C-band (3.3 – 3.6 GHz). The overall dimensions are 105 mm × 105 mm × 27 mm. The antenna consists of two pairs of coplanar symmetrical dipoles, and two microstrip lines, and square loop-shape structures, and two metal cylinders and a reflector. The square loop-shape structure connected by the microstrip line is electromagnetically coupled to feed the dipoles, and its dipoles and metal cylinder are connected to the reflector. By changing the geometry of the square loop structures and symmetrical dipoles, the impedance bandwidth of the design is 51.11 % (2.17 to 3.66 GHz), the isolation is greater than 25 dB, the half-power beamwidth of the main beam is 65  5 degree, and the gain is from 8.3 to 9.4 dBi. The second dual-polarized slot dipole antenna design for the LTE 2300 / LTE 2500 / WRC15 C-band / China 5G C-band. The overall dimension is 104 mm × 104 mm × 33.8 mm. The proposed antenna is electromagnetically coupled through a microstrip line to feed the slot dipoles. The impedance bandwidth of the design is 48.23  (2.25 – 3.68 GHz), and the isolation is greater than 25 dB, the half-power beamwidth of the main beam is 65  5 degree, the front-to-back ratio better than 27 dB, and the gain is from 8.6 to 9.7 dBi. In order to improve the isolation and pattern, two metal cylinders and metal metallic loop are added to the antenna configuration.

碩士
國立臺南大學
光電工程研究所
100
This paper presents a broadband antenna presently being used in LTE 700/GSM 850/900 systems for smart phone applications. The proposed CPW-fed monopole antenna consists of the oval-C and dual-L shape strips. The impedance bandwidth defined by return loss S11 ≦ -10 dB is from 660 to 975 MHz. The antenna bandwidth includes LTE 700 (698-806 MHz), GSM 850 (824-894 MHz), and GSM 900 (880-960 MHz) GSM 850/900 bands. Long term evolution (LTE) is one of the mobile communication technologies that are targeting the 700 MHz band (LTE bands 13 and 17: 698-806 MHz). The LTE service is expected to provide better communication quality than the existing services, such as GSM 850 (824-894 MHz), GSM 900 (880-960 MHz). However, mobile phones are desired to be able to cover at least a few of the existing service bands and LTE bands at the same time especially before the wide spread of the LTE services. The measured peak gains are 1.5 ~ 2.9 dBi with sufficient bandwidths to cover modern portable communication devices. The radiation efficiencies are all larger than 75% for an entire band. The simulated and measured results show the good agreement. This proposed antenna with multiband, broadband matched impedance, stable radiation patterns, constant antenna gains and compact size can be suitable for multi-mode applications.

The high deployment and maintenance costs of last mile wireline networks (i.e., DSL and cable networks) have urged service providers to search for new cost-effective solutions to provide broadband connectivity. Broadband wireless access (BWA) networks, which offer a wide coverage area and high transmission rates in addition to their fast and low-cost deployment, have emerged as an alternative to last mile wireline networks. Therefore, BWA networks are expected to be deployed in areas with different terrain profiles (e.g., urban, suburban, rural) where wireless communication faces different channel impairments. This fact necessitates the adoption of various transmission technologies that combat the channel impairments of each profile. Implementation scenarios of BWA networks considered in this thesis are multicarrier-based direct transmission and single carrier-based cooperative transmission scenarios. The performance of these transmission technologies highly depends on how resources are allocated. In this thesis, we focus on the development of practical resource allocation schemes for the mentioned BWA networks implementation scenarios. In order to develop practical schemes, the imperfection of channel state information (CSI) and computational power limitations are among considered practical implementation issues. The design of efficient resource allocation schemes at the MAC layer heavily relies on the CSI reported from the PHY layer as a measure of the wireless channel condition. The channel estimation error and feedback delay renders the reported CSI erroneous. The inaccuracy in CSI propagates to higher layers, resulting in performance degradation. Although this effect is intuitive, a quantitative measure of this degradation is necessary for the design of practical resource allocation schemes. An approach to the evaluation of the ergodic mutual information that reflects this degradation is developed for single carrier, multicarrier, direct, and cooperative scenarios with inaccurate CSI. Given the CSI estimates and estimation error statistics, the presented evaluation of ergodic mutual information can be used in resource allocation and in assessing the severity of estimation error on performance degradation. A point-to-multipoint (PMP) network that employs orthogonal frequency division multiple access (OFDMA) is considered as one of the most common implementation scenarios of BWA networks. Replacing wireline networks requires not only providing the last mile connectivity to subscribers but also supporting their diverse services with stringent quality of service (QoS) requirements. Therefore, the resource allocation problem (i.e., subcarriers, rate and power allocation) is modeled as a network utility maximization (NUM) one that captures the characteristics of this implementation scenario. A dual decomposition-based resource allocation scheme that takes into consideration the diversity of service requirements and inaccuracy of the CSI estimation is developed. Numerical evaluations and simulations are conducted to validate our theoretical claims that the scheme maximizes resource utilization, coordinates with the call admission controller to guarantee QoS, and accounts for CSI inaccuracy. Cooperation has recently received great attention from the research community and industry because of its low cost and fast deployment in addition to the performance improvement it brings to BWA networks. In cooperative scenarios, subscribers cooperate to relay each other's signals. For this implementation scenario of BWA networks, a robust and constrained Kalman filter-based power allocation scheme is proposed to minimize power consumption and guarantee bit error probability (BEP) requirements. The proposed scheme is robust to CSI inaccuracy, responsive to changes in BEP requirements, and optimal in allocating resources. In summary, research results presented in this thesis contribute to the development of practical resource allocation schemes for BWA networks.

碩士
國立交通大學
理學院應用科技學程
99
The purpose of this research is to observe the fast developing of communication industry. At the moment of the 4G technology beginning, we try to forecast its development and suggest how the industrial deployment should be. The main objects are LTE and WiMAX. We observe the technology development and also the changing of their market. Then we use Senrio and Dephi to find out the possibility of its development. The result of this resourch shows that LTE will replace 3G and be the next main technology of wireless communication. WiMAX will be in the middle of that and phase out soon. Finally, we estimate that there will be two major products based on 4G technology. One is personal mobile vedio device, and another is smart device on vehicle. For further research, we suggest that application and service on 4G network could be a good direction.

碩士
國立中山大學
企業管理學系研究所
91
In attempt to build to a high technological and digital communication Taiwan,the country government plan to build up the broadband network to six million subscribers in its challenging the country developed 6 years program in 2008. The construction of broadband network will be the main stream of market. Chunghwa Telecom’s ADSL program is satisfied with the requirement of society. The object of this research is based on the ADSL customers at the broad Kaohsiung Area of Chunghwa Telecom. The investigation area encompassKaohsiung city, Fongsun, Kungsun, Chiesun of Kaohsiung County. The investigation adopts the method of questionnaire. Data are collected via Stratified Random Sampling, and analyzed by SPSS statistic software. It is also implemented by using seven factors that affect customer satisfaction like service contents, prices, convenience, enterprise images, service facilities, service staffs and service process in connection with service quality, customer satisfaction, and customer loyalty. The result of this investigation occurs as below: There is a remarkable different between customer’s satisfaction and values in response to the practical aspect of quality. Different customers respond with market different from sex, age, and choosing a place to use Internet are varied in satisfaction. The group of customer responds satisfaction from different person requires Internet service. It exist conspicuous difference in the choice. The obvious mutuality between the practical aspect of service quality and customer’s satisfaction has positive effects. The practical aspect of service quality in different place of using Internet, the item of service quality, and customer satisfaction are clearly differ from each others. Different customers respond with market different from sex, marriage, and age to use Internet are varied in loyalty. The group of customer who requires different personal Internet service is remarkable difference from loyalty in the choice. The obvious mutuality between the practical aspect of service quality and customer’s loyalty has positive effects. The practical aspect of service quality in different place of using Internet, the item of service quality, and customer loyalty are clearly differ from each others. According to the above-mentioned result of research, it brings up suggestions depending on service contents, prices, convenience, enterprise images, service facilities, service staffs, and service process

碩士
中原大學
企業管理研究所
95
The broadband network technology of Asymmetric Digital Subscriber Line (ADSL) is hot in the market all over the world. Especially in Asia and Europe, the ADSL broadband access network has become the master technology. ADSL has high bandwidth, low cost, and so convenient that can be used in the existing telephone cable; with so many advantages, ADSL has been by big telecom. The connection of ADSL is point to point, has good service quality, and is getting more and more popular. In recent years, because Chunghwa Telecom Co., Ltd. try to construct ADSL network hardly and take promotions to improve the number of users, ADSL has become very popular, and the users of ADSL is saturated now. By the dependence and the demand of ADSL, people in Taiwan also ask telecom to provide better service quality in maintenance. The research regards the ADSL users in nortern Taiwan as the objects. This study used “convenience sampling” to take the questionnaire survey, and sampled 500 clients in more than 2,010,000 users of nortern Taiwan, with 396 valid questionnaires reclaimed. This study adopted the PZB model, proposed by Parsuraman, Zeithamland and Berry, to analyze the gaps in service quality. This study took the service quality of ADSL maintenance into account, and studied the relation between the customer gap of service quality and the customer satisfaction. Furthermore, this study researched if there is any obvious influence of the customer satisfaction on customer loyalty. In otherwise, this study studied whether the influence of gap of customer service quality on customer satisfaction will be interfered by users and their background In data analyzing, this study took software SPSS version 10.0 as the statistical analysis tool. The regression model is constructed, and studies the gap of service quality versus the effect of broadband user’ satisfaction. There are three entries of the major result in this research: 一、For customers’ cognition and expectation in the gap of service quality,“Eliability”and“Assurance”will affect the degree of customer satisfaction. 二、Positive relationship is reflected by customer satisfaction and loyalty. 三、The influence of gap customer service quality on customers’ satisfaction will be interfered by demographic characteristics such as Sex, Age, Education level, and use characteristics of differential transmission rate of ADSL.