Com a necessidade da obtenção da informação ser disponibilizada em vários locais simultaneamente, mostrando resultados on-line, faz com que as redes de comunicação de dados estejam cada vez mais presentes no dia-a-dia das pessoas e das empresas obrigando a constante busca por novas técnicas e meios de estabelecer essa comunicação. Disponibilizar sistemas de monitoração, supervisão e controle de dados on-line em máquinas e equipamentos em tempo real, não é uma tarefa nada fácil. Na estratégia de investimento, a escolha apropriada da rede e o meio de estabelecer essa comunicação na integração dos diversos equipamentos distribuídos em locais diferentes (remotos) é um fator importante para o sucesso dos dados que se queiram monitorar. O presente trabalho mostra as tecnologias de comunicação sem fio – Wireless e Celular através de uma pesquisa e estudo de caso feito em Laboratório da UFRGS e Faculdade SATC com a criação de um protótipo de uma interface de aquisição de dados utilizando a rede celular GSM/GPRS para simular a transmissão e recepção de dados para o monitoramento remoto de 02 (duas) variáveis aqui definidas como vibração da torre e desgaste de pastilha de freio em aerogerador de pequeno porte. Os dados aqui estudados mostram resultados que podem ser úteis para qualquer empresa que planeje implantar um sistema de monitoramento remoto através da Rede Celular (GSM/GPRS). Apesar de no experimento ter sido utilizado variáveis de um aerogerador, são mostradas outras aplicações possíveis de monitoramento remoto utilizando-se o canal de comunicação ar. / With the need to obtain the information be made available in several places simultaneously, showing results online, means that the networks of communication of data are increasingly present in the day-to-day of people and businesses requiring the constant search for new techniques and means to establish such communication. Enabling systems for monitoring, surveillance and control of data online in machinery and equipment in real time, nothing is not an easy task. In investment strategy, the choice of appropriate network and the means to establish this communication in the integration of the various equipment distributed in different locations (remote) is an important factor for the success of the data that we want to track. The present work shows the wireless communication technologies-Wireless and Mobile through a search and case study done in the laboratory and UFRGS and SATC College with the creation of a prototype of an interface for data acquisition using the GSM / GPRS cellular network to simulate the transmission and reception of data to the remote monitoring of 02 (two) variables here defined as vibration of the tower and wear of the brake chip in wind power of small. The data studied here show us results that can be useful for any business that plan deploy a system for remote monitoring via the Network Mobile (GSM / GPRS). Although the experiment have used variables of a wind power, are shown other possible applications of remote monitoring using the channel of communication wireless.

In order to develop and secure the functionality of its cellular communications systems, Ericsson deals with numerous R&D and I&V activities. One important aspect is interoperability with mobile terminals from different vendors on the world market. Therefore Ericsson co-operates with mobile platform and user equipment manufacturers. These companies visit the interoperability developmental testing (IoDT) laboratories in Linköping to test their developmental products and prototypes in order to certify compliance with Ericsson's products. The knowledge exchange is mutual, Ericsson as well as the user equipment manufacturers benefit from the co-operation. The goal of this master's thesis performed at Ericsson AB is to suggest areas in which the IoDT testing can be automated in order to minimize time consuming and tedious work tasks. Primarily the search should be aimed at replacing manual tasks in use today. The thesis suggests a number of IoDT tasks that might be subject for automation. Among these one is chosen for implementation. The thesis also includes an implementation part. The task that has been chosen for implementation is the network verification after base station controller software upgrade procedure. This is not a core IoDT function but it implies a lot of work, and is often performed. The automation project is also supposed to act as a springboard for future automation within IoDT. The forthcoming LTE standard will require a lot of IoDT testing, and therefore the automation capabilities should be investigated. The thesis shows that automation work is possible, and that the startup process is straightforward. Existing tools are easy to use, and well supported. The network verification automated test scope has been successful.

The Global System for Mobile Communications (GSM) is the most widely used cellular technology in the world. Approximately 800 million people around the world are using GSM for different purposes, but mostly for voice communication and SMS. For GSM, like many other widely used systems, security is crucial. The security involves mechanisms used to protect the different shareholders, like subscribers and service providers. The aspects of security that this report covers are mainly anonymity, authentication and confidentiality. The important aspects of the system that need protection are described, along with the implementation of mechanisms used for the protection. It appears that many of the very valuable aspects of GSM can be attacked. The anonymity of a GSM user is compromised resulting in the attacker being able to observe the time, rate, length, sources or destinations of e g calls. Even tracking a subscriber’s movements becomes possible. However, a passive attack is not sufficient to perform these attacks. The attacker needs to mount an active attack using equipment offering base station functionality. Authentication is a crucial aspect of a wireless communication system due to the nature of the medium used, i e the radio link that is available to every one and not only the legitimate entities. Even the authentication mechanisms are attacked. It is possible to clone a subscription either by having physical access to the smart card or over the air interface. Cloning a subscription over the air requires base station functionality. The most obvious threat against communication systems is eavesdropping on conversations. The privacy of GSM conversations is protected using some version of the A5 algorithm. There are several impressive cryptanalytical attacks against these algorithms, that break the encryption and make it possible to eavesdrop in real-time. Most of these algorithms require, however, extensive computation power and unrealistic quantities of known plaintext, which make it difficult to use them in practice. Difficulties using cryptanalytical attacks to break the confidentiality of GSM calls does not mean that conversations are well protected. Loopholes in the protocols used in GSM make it possible for an outsider, with access to sufficient equipment, to eavesdrop on conversations in real-time. In the presence of these threats and vulnerabilities it is justified to wonder whether GSM provides sufficient security for users with very valuable information to communicate. These users may be military organisations, senior management personnel in large companies etc. GSM’s current security model does note provide sufficient protection for these entities. An additional layer of security should be added to the current security model.

This master thesis has been done at Enea Epact AB. The purpose of this thesis is to develop and implement a Link Quality Control algorithm for GPRS/EPGRS in the current testing tool. A Link Quality Control (LQC) shall take quality values from mobile stations and base stations and decide a codingsscheme that opimizes the throughput of data. The Advantage with LQC is that it adapts the used coding scheme to the channel quality. If the channel quality is too bad for the used coding scheme, a slower coding scheme with more redundancy should be selected. On the other hand, if the channel quality is too good for the used coding scheme, LQC should recommend a faster coding scheme with less redundancy. The testing tool is now using a static coding schme that doesn’t change during a data session. An LQC is therefore necessary for better simulation of the traffic and to make the tests more real.

This thesis deals with output power calibration of a mobile platform that supports EGPRS.Two different topics are examined. First some different measurement methods are compared concerning cost efficiency, accuracy, and speed and later measurements are carried out on a mobile platform. The output power from the mobile platform is controlled by three parameters and the influence on the output power when varying those parameters is investigated and presented. Furthermore, two methods of improving the speed of the calibration are presented. The first one aims to decrease the number of bursts to average over as much as possible. The conclusion is that 10-20 bursts are enough for GMSK modulation and about five bursts for 8PSK modulation. The purpose of the second investigation is to examine the possibility to measure the output power in one modulation and frequency band, and then calculate the output power in the other bands. The conclusion in this case is that, based on the units investigated, it is possible for some values of the parameters and in some frequency bands. However, more units need to be included in the basic data for decision-making and it is possible that the hardware variation is too large.

The company Sensefarm develops in the field of precision agriculture, more specifically a product for measuring and logging information on local environmental conditions. The collected data is transmitted to a remote server using GSM technology. They are looking into ways to improve their product. The purpose of this project is to evaluate the M66 GSM module and the accompanied OpenCPU technology. In the current product the GSM module is only used for the communication with the server. All other processing is done by a dedicated processor. The OpenCPU technology allows for running customized firmware on the GSM module, possibly allowing it to take over the responsibilities of the dedicated processor. An application implementing all the necessary functionality was developed to test this capability. The finished application was able to fulfill all the requirements specified, although it was not able to be tested in the field.

La croissance rapide du trafic aérien et les besoins en nouveaux services notamment pour les passagers imposent l'introduction de nouveaux moyens de communication pour les avions avec une bande passante globale fortement accrue. Les satellites sont appelés à jouer un rôle important dans ce contexte, non seulement en complément des systèmes terrestres pour les services « cockpit » (services ATM, Air Traffic Management) mais aussi pour les services « cabine » (In-Flight Entertainment). L'objectif de la thèse est d'étudier l'architecture d'un système satellite supportant l'ensemble de ces services, en se focalisant sur l'architecture du terminal embarqué à bord des aéronefs. L'architecture retenue repose sur des liaisons DVB-S2/DVB-RCS normalisées par l'ETSI. Cette option permet d'utiliser efficacement l'importante bande passante disponible en bande Ka pour les services mobiles aéronautiques (allocation primaire) ou en bande Ku (allocation secondaire). Ces normes ont été conçues pour les applications multimédia (Broadband Satellite Multimedia). Le défi est alors d'utiliser de telles liaisons satellite pour des services aux caractéristiques et besoins fortement hétérogènes. Par ailleurs, l'utilisation de la bande Ka n'est pas concevable sans l'activation de techniques de lutte contre les affaiblissements (FMT – Fade Mitigation Techniques). L'utilisation d'une marge statique conduit à une perte importante de capacité. Les techniques FMT reposent sur une évaluation dynamique du bilan de liaison et permettent une modification de la forme d'onde. Le système utilise ainsi la forme d'onde la plus efficace spectralement pour chaque terminal et maximise la capacité globale du système. Par contre, chaque terminal observe une modification de la ressource allouée au fil du temps. L'objectif de la thèse est de concevoir une architecture au niveau terminal qui permette d'exploiter les liaisons DVB-S2/RCS afin de fournir les services passagers (Internet et téléphonie mobile de type GSM/UMTS) et un canal haute fiabilité pour les services aéronautiques. Deux approches ont été retenues. La première repose sur une application du modèle ETSI BSM (Broadband Satellite Multimedia) en couches séparant strictement les couches dépendantes satellite et les couches indépendantes satellite. Les simulations de cette architecture montrent que les liaisons ne peuvent être utilisées de façon efficace sans une interaction entre couches afin de tenir compte de l'évolution de la capacité disponible. La seconde approche consiste en la concentration de la gestion de la ressource et la gestion de la qualité de service dans la même couche protocolaire. L'idée de départ est d'utiliser la méthode d'encapsulation générique Generic Stream Encapsulation (GSE). GSE a été conçu pour la projection des paquets de couches supérieures à l'intérieur des trames DVB-S2. GSE tient compte de la taille variable des trames DVB-S2 et introduit une capacité de multiplexage entre différents flux (identification de fragments). Sur cette base, une gestion de l'accès est introduite pour gérer la liaison DVB-RCS au format MF-TDMA. Nous introduisons ainsi une utilisation conjointe de GSE, d'une politique de service différentiée et de flux de signalisation inter-couches (« cross-layer »). Les performances des deux approches sont étudiées à l'aide d'un modèle de simulation développé à l'aide du logiciel OPNET Modeler (simulations à événements discrets). Les résultats obtenus démontrent le meilleur comportement de la seconde architecture avec une meilleure utilisation de la ressource et des performances de transmission satisfaisant les objectifs. / The rapid growth of air traffic needs a new communication infrastructure with increased bandwidth, high speed services and applications to satisfy expected air-ground communication requirements. Satellite communication systems play a significant role in this context, not only as a complement to terrestrial systems for Air Traffic Management (ATM) by offering global coverage but also as a promising solution to enrich In-Flight Entertainment (IFE) for passengers. DVB-S2/RCS technology is an attractive proposition to provide the cost-effective broadband services for both ATM and IFE, mainly because a large radio bandwidth is primarily allocated to aeronautical mobile communications in Ka-band, where the open standards DVB are implemented. However, such system design with convergence of heterogeneous traffics involves two main challenges. Firstly, using Ka-band means the implementation of Fade Mitigation Techniques (FMT) in order to cope with deep fades caused by atmospheric attenuation. Otherwise, the waste of capacity would be excessively high in a constant link margin design. FMT adapt in real time the link budget to the propagation conditions, this adaptivity has an impact not only on physical layer but also on upper layers. An efficient ressource management strategy with dynamic bandwidth allocation is required in this case, especially in DVB-RCS return link where FMT are not natives. Secondly, the proposed system must be able to multiplex the trafic flows with highly different characteristics and Quality of Service (QoS) expectations into a single link, the corresponding capacity management and QoS support seem with higher complexity. In this paper, we present an adaptive system design using a single DVB-S2/RCS based satellite link to provide Internet access and mobile telephony (GSM/UMTS) for passengers and a high-reliability channel for ATM. Concerning the airborne terminal architecture, two approaches are investigated. The first one is in compliance with ETSI Broadband Satellite Multimedia (BSM) architecture and based on a layering paradigm. The conducted simulation experiments highlight the need of dynamic interactions and adaptations among the layers to achieve an overall performance optimization. We propose then an enhanced approach with the concentration of both resource allocation and QoS management at the same interface – adaptation layer. The idea comes from the success of the recent Generic Stream Encapsulation (GSE) protocol, which carries the network protocol packets over DVB-S2 forward link in a simple, flexible and efficient way, especially when used with Adaptive Coding and Modulation (ACM). Furthermore, GSE can be easily extended to use in our design for DVB-RCS return link thanks to a proper design of MF-TDMA structure in which the suitable FMT (ACM and Dynamic Rate Adaptation) are context-aware configured. With the combined use of GSE, service policy and the interactions between adaptation and access layers, incoming heterogeneous traffics can be dynamically scheduled, segmented and encapsulated at the same adaptation layer. Performance evaluation of two proposed approaches is derived by a network-level simulation model developed using OPNET. Results prove the enhanced approach outperforms the first one leading to better resource utilization and satisfactory performance.

No description available.

The subject of the diploma thesis are procedures in EPS network related to the operation of mobile terminals. In the introduction of my work I described the EPS system, including the quality of services and bearers. The following section focuses on control procedures in the EPS system such as attach network procedure, detach procedure, service request, handover or tracking area procedure. Further, three technologies for Internet of Things were described, namely EC-GSM-IoT, LTE-M and NB-IoT. All the procedures mentioned above were also captured in the experimental VUT EPS network and analyzed by TravelHawk using software M5 and Wireshark. Theoretical and practical findings were subsequently used out for setting of laboratory task for subject MKPM.

Content of this diploma thesis is project of the digital control design for a thyristor source with GSM communication. Designed for corrosion protection. The work contain design of the whole device from the initial proposals of the electro diagrams up to finished product. It describes the events that arise in corrosion, explains the principle of operating a thyristor as a power switch. It also describes the creation and structure of a simple menu using the STM32 microprocessor. It explains the principle of controlling a source. Next, it deals with controlled rectifiers using a thyristor.