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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
241

Automotive Telematics Services based on Cell Broadcast

Gundlegård, David January 2003 (has links)
<p>Cell Broadcast is a relatively old technique within the GSM-network which makes it possible to broadcast text messages to one or more cells in the network. As efforts in Sweden have been made to develop both traffic safety and information technology, the automotive telematics market is predicted to grow rapidly in the near future. The characteristics of Cell Broadcast make it especially suitable for automotive telematics services. The main purpose of this thesis is to investigate possible automotive telematics services based on Cell Broadcast and how these services can affect traffic safety. </p><p>The most important characteristics for Cell Broadcast in the automotive telematics market are close connection to the GSM/UMTS network, location-based information and information of push character. These characteristics allows the mobile operator to offer a number of automotive telematics services based on Cell Broadcast, some of them as service provider and some of them in joint ventures with car and mobile terminal manufacturers.</p>
242

Demonstrationsutrustning för M2M tillämpning / Equipment for demonstration of M2M application

Karlsson, Patrik January 2004 (has links)
<p>Detta examensarbete är ett utvecklingsarbete av demonstrationsutrustning för enkel visning av fördelarna med M2M-tekniken vid insamling av mätdata och automatisk övervakning. Arbetet består av en praktisk del, som utgörs av demonstrationsväskan, och en mer teoretisk del, som utgörs av demonstrationsprogrammet. </p><p>Programmet har utvecklats till att med ett mätkort kopplat till en PC samla in mätvärden (spänningar), dessa skickas sedan som ett SMS med ett GSM-modem till en mottagare. Mottagaren kan vara en serviceman som vill ha felmeddelanden från utrustning inom dennes ansvarsområde, mottagaren kan även vara en server som rymmer en databas vilken används för att spara viktiga mätvärden för längre tid, t.ex. loggning av elförbrukning hos något kraftbolags kund. </p><p>Det hela har alltså resulterat i ett färdigt och väl fungerande program, som utför just det som är uppdraget ovan. Mätresultatenhar tillräcklig noggrannhet för detta uppdrag om att demonstrera fördelarna med M2M-tekniken, och mätresultatet kommer även fram till mottagaren i sin rätta form. </p><p>Detta betyder att M2M Communication AB nu kan demonstrera vinsten med M2M-tekniken för potentiell kund på ett enkelt och förklarande sätt. Integrerat i demonstrationsutrustningen har nu också företaget fått en enkel och självklar utrusning för att i praktiken se hur nya givare och annan utrusning fungerar ihop med ComHost 300 som är företagets primära produkt. </p> / <p>The goal with this master thesis is to develop a simple equipment to show the advantage of using M2M-technic when collect measured data and when using automatic monitoring of alarm and sensors. The thesis is divided in two parts, a practical part that corresponds to a case with sensors and equipment. The case is used to collect measure data to be used when demonstrating the theoretical part, which corresponds to the software program. The software program is developed to measure voltage with the data acquisition card, and then send them as a SMS text message via the GSM network. For this tasks the software also have to control the GSM-modem. This text message is either sent to a computer for logging in a database, or to the service department who owns the equipment measured. </p><p>This work has ended up in well function software that can be installed on a PC-system with a Windows 2000(tm) operation system. The accuracy on the measured data is good enough for the task to demonstrate the function of the M2M-technic. The text message is also arrive to the receiver as expected. </p><p>The result of this master thesis ends up giving the company M2M Communication AB the possibility to demonstrate the M2M-technic on a simple and explaining manner for a potential customer. Integrated in the new equipment the company also has been given a possibility to test new sensors and signal sources in a real world M2M test.</p>
243

Analysis and implementation of a call simulator for Mobile@Home at Ericsson AB / Analys och implementering av en samtalssimulator för Mobile@Home, Ericsson AB

Larsson, Rasmus, Wikström, Edvard January 2004 (has links)
<p>Mobile telephony technology like GSM made portable telephony a possibility. The arising and development of the Internet made a revolutionary change to communication and interchange of information. Bluetooth wireless technology revolutionizes personal connectivity by providing freedom from wired connections. Combining these technologies together brings the concept of Mobile@Home of Ericsson. </p><p>Mobile@Home is a fixed-mobile convergence concept using the fixed network to carry present and future mobile services (e.g. voice, video, mail and Internet access) all the way to the home or office. By combining the high bandwidth of the fixed access network with the wireless technology of Bluetooth, Mobile@Home makes it possible to deliver high bandwidth to the mobile phone. Mobile@Home requires a Bluetooth enabled mobile phone and a Bluetooth enabled HBS (Home Base Station), placed at the home or office. By means of fast IP access (ADSL, cable modem etc.) the HBS connects into the standard mobile core network through a HBSC (Home Base Station Controller). </p><p>The purpose of this thesis is the generation of simulated traffic between the HBS and HBSC and to analyze its behavior. This primary involves generation of signaling through an internal protocol, provided by Ericsson, for management and call control, and generation of GSM EFR (Enhanced Full Rate) voice streams over the RTP (Real Time Protocol) protocol. The simulation will consist of both the HBS and MS (Mobile Station). A set of HBS: s with attached MS will call one another through the HBSC. In this assignment only the GSM signaling will be considered because of time and scope limitations. The goal is to validate the RTP traffic generated towards the HBSC. Parameters like packet loss, packet delay and erroneous packets will be analyzed.</p>
244

Advanced Traffic Service / Avancerad Trafiktjänst

Löfås, Peter January 2005 (has links)
<p>More and more travellers use navigation-aid software to find the way while driving. Most of todays systems use static maps with little or no information at all about currently yeilding roads conditions and disturbances in the network. It is desirable for such services</p><p>in the future to include information about road works, accidents, surface conditions and other types of events that affects what route is currently the best.</p><p>It is also desirable to notify users about changes in the prerequisites of the chosen route after they have started their trip.</p><p>This thesis investigates methods to include dynamic traffic information in route calculations and notifying users when the characteristics change for their chosen route.</p><p>The thesis utilizes dynamic traffic information from The Swedish Road Agencys (Vägverket) central database for traffic information, TRISS and calculates affected clients with help of positioning through the GSM network.</p>
245

Advanced Traffic Service / Avancerad Trafiktjänst

Löfås, Peter January 2005 (has links)
More and more travellers use navigation-aid software to find the way while driving. Most of todays systems use static maps with little or no information at all about currently yeilding roads conditions and disturbances in the network. It is desirable for such services in the future to include information about road works, accidents, surface conditions and other types of events that affects what route is currently the best. It is also desirable to notify users about changes in the prerequisites of the chosen route after they have started their trip. This thesis investigates methods to include dynamic traffic information in route calculations and notifying users when the characteristics change for their chosen route. The thesis utilizes dynamic traffic information from The Swedish Road Agencys (Vägverket) central database for traffic information, TRISS and calculates affected clients with help of positioning through the GSM network.
246

Contribución al diseño de los niveles físico y MAC/LLC de redes de comunicaciones móviles orientadas a aplicaciones y servicios multimedia

Sanz Gil, Roberto 23 March 2001 (has links)
Esta tesis tiene como objetivo final la propuesta de un protocolo de acceso al medio imbricado con los parámetros de nivel físico que dan soporte a dicho protocolo. Puesto que la propuesta se basa en un esquema TDMA, se eligen como base del análisis los sistemas de segunda generación GSM, TETRA y DECT, a partir de los cuales se extrapolan determinados parámetros a fin de sintonizarlos con los sistemas de tercera generación en su especificación TDMA. Se evalúan dichos sistemas a nivel físico sobre diferentes modelos de canal de propagación y distintas técnicas de compensación implementadas en el receptor: ecualizadores implementados sobre filtros transversales y antenas adaptativas. Además, se implementan y evalúan algoritmos de ecualización sencillos como LMS o RLS y más complejos como algoritmos bidireccionales sobre ecualizadores DFE. La elección de una u otra opción condicionará fuertemente el diseño del protocolo de acceso propuesto en el subnivel MAC. / This thesis has as final aim the proposal of a medium access protocol (MAC) closely related to the physical layer parameters that support such protocol. As the proposal is based on a TDMA scheme, three representative systems belonging to the second generation of mobile communication systems have been chosen: GSM, TETRA and DECT, which are employed to extract some parameters in order to tune them with the third generation systems in its TDMA specification. Such systems are evaluated at physical layer over different propagation channel models with several compensation techniques implemented on the receiver. As well, equalizers based on digital filters and adaptive antennas are utilized. The equalization algorithms evaluated include from the simplest ones like LMS or RLS to bidirectional algorithms over DFE structure. Choosing one or another option will strongly condition the design of the proposed access protocol within the MAC sublayer.
247

Automotive Telematics Services based on Cell Broadcast

Gundlegård, David January 2003 (has links)
Cell Broadcast is a relatively old technique within the GSM-network which makes it possible to broadcast text messages to one or more cells in the network. As efforts in Sweden have been made to develop both traffic safety and information technology, the automotive telematics market is predicted to grow rapidly in the near future. The characteristics of Cell Broadcast make it especially suitable for automotive telematics services. The main purpose of this thesis is to investigate possible automotive telematics services based on Cell Broadcast and how these services can affect traffic safety. The most important characteristics for Cell Broadcast in the automotive telematics market are close connection to the GSM/UMTS network, location-based information and information of push character. These characteristics allows the mobile operator to offer a number of automotive telematics services based on Cell Broadcast, some of them as service provider and some of them in joint ventures with car and mobile terminal manufacturers.
248

Demonstrationsutrustning för M2M tillämpning / Equipment for demonstration of M2M application

Karlsson, Patrik January 2004 (has links)
Detta examensarbete är ett utvecklingsarbete av demonstrationsutrustning för enkel visning av fördelarna med M2M-tekniken vid insamling av mätdata och automatisk övervakning. Arbetet består av en praktisk del, som utgörs av demonstrationsväskan, och en mer teoretisk del, som utgörs av demonstrationsprogrammet. Programmet har utvecklats till att med ett mätkort kopplat till en PC samla in mätvärden (spänningar), dessa skickas sedan som ett SMS med ett GSM-modem till en mottagare. Mottagaren kan vara en serviceman som vill ha felmeddelanden från utrustning inom dennes ansvarsområde, mottagaren kan även vara en server som rymmer en databas vilken används för att spara viktiga mätvärden för längre tid, t.ex. loggning av elförbrukning hos något kraftbolags kund. Det hela har alltså resulterat i ett färdigt och väl fungerande program, som utför just det som är uppdraget ovan. Mätresultatenhar tillräcklig noggrannhet för detta uppdrag om att demonstrera fördelarna med M2M-tekniken, och mätresultatet kommer även fram till mottagaren i sin rätta form. Detta betyder att M2M Communication AB nu kan demonstrera vinsten med M2M-tekniken för potentiell kund på ett enkelt och förklarande sätt. Integrerat i demonstrationsutrustningen har nu också företaget fått en enkel och självklar utrusning för att i praktiken se hur nya givare och annan utrusning fungerar ihop med ComHost 300 som är företagets primära produkt. / The goal with this master thesis is to develop a simple equipment to show the advantage of using M2M-technic when collect measured data and when using automatic monitoring of alarm and sensors. The thesis is divided in two parts, a practical part that corresponds to a case with sensors and equipment. The case is used to collect measure data to be used when demonstrating the theoretical part, which corresponds to the software program. The software program is developed to measure voltage with the data acquisition card, and then send them as a SMS text message via the GSM network. For this tasks the software also have to control the GSM-modem. This text message is either sent to a computer for logging in a database, or to the service department who owns the equipment measured. This work has ended up in well function software that can be installed on a PC-system with a Windows 2000(tm) operation system. The accuracy on the measured data is good enough for the task to demonstrate the function of the M2M-technic. The text message is also arrive to the receiver as expected. The result of this master thesis ends up giving the company M2M Communication AB the possibility to demonstrate the M2M-technic on a simple and explaining manner for a potential customer. Integrated in the new equipment the company also has been given a possibility to test new sensors and signal sources in a real world M2M test.
249

Direct Conversion RF Front-End Implementation for Ultra-Wideband (UWB) and GSM/WCDMA Dual-Band Applications in Silicon-Based Technologies

Park, Yunseo 28 November 2005 (has links)
This dissertation focuses on wideband circuit design and implementation issues up to 10GHz based on the direct conversion architecture in the CMOS and SiGe BiCMOS technologies. The dissertation consists of two parts: One, implementation of a RF front-end receiver for an ultra-wideband system and, two, implementation of a local oscillation (LO) signal for a GSM/WCDMA multiband application. For emerging ultra-wideband (UWB) applications, the key active components in the RF front-end receiver were designed and implemented in 0.18um SiGe BiCMOS process. The design of LNA, which is the critical circuit block for both systems, was analyzed in terms of noise, linearity and group delay variation over an extemely wide bandwidth. Measurements are demonstrated for an energy-thrifty UWB receiver based on an MB-OFDM system covering the full FCC-allowed UWB frequency range. For multiband applications such as a GSM/WCDMA dual-band application, the design of wideband VCO and various frequency generation blocks are investigated as alternatives for implementation of direct conversion architecture. In order to reduce DC-offset and LO pulling phenomena that degrade performance in a typical direct conversion scheme, an innovative fractional LO signal generator was implemented in a standard CMOS process. A simple analysis is provided for the loop dynamics and operating range of the design as well as for the measured results of the factional LO signal generator.
250

NOVEL ANTENNAS FOR MOBILE PHONES AND WLAN APPLICATIONS

Yeh, Shih-Huang 19 April 2003 (has links)
This paper proposes novel antenna designs for cellular phones and WLAN (Wireless LAN) applications. For cellular phones, a dual- frequency PIFA (Planar Inverted-F Antenna) loaded with a chip inductor is constructed. In order to decrease the construction cost, PIFAs without a loading chip inductor for GMS/DCS phones are devised. Besides, a PIFA-monopole antenna for GSM/DCS/PCS is also proposed. For WLAN application, a dual-band PIFA for 2.4/5.8 GHz and a dual-band integrated monopole antenna for 2.4/5.2 GHz are shown. Finally, a novel metal-plate WLAN antenna, having a simple structure and being easy to construct with low cost, is presented.

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