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<p>Developing software for mobile terminals is a challenging task because the actual hardware is </p><p>not available at the beginning of the software development phase. Once a hardware prototype is </p><p>available the software development can continue on that platform. But before that a need for a </p><p>model of the actual hardware is needed, hence some kind of emulator or simulator needs to be the </p><p>developed to give the software developers a head start. The aim of this master thesis is to do a </p><p>market survey of the available simulators for the ARM9E CPU and attached devices in a base- </p><p>band chip and test their flexibility in terms of adding additional devices (both external and on </p><p>chip), and also to implement a simulator using the C++ language. The goal is a modular structure </p><p>for easy addition of certain components such as memory-interfaces, external devices etc. Another </p><p>important part is the profiling of the executed code to instrument the execution in different ways, </p><p>and efficiency to allow fast execution. The conclusion of the market study is that due to the high </p><p>price of these simulators (1.5K€-40k€), we need to design our own simulator. Our simulator </p><p>consists of different blocks; some of them are merely stubbed while others like the memory and </p><p>CPU core are modelled more in detail. The performance of the simulator is around 200 KIPS due </p><p>to the overhead in the debugging functionality. By removing the debugging overhead and </p><p>optimizing the memory handling we could achieve at least 1 MIPS on the ARM execution and 5 </p><p>MIPS on the Thumb execution.</p>

Developing software for mobile terminals is a challenging task because the actual hardware is not available at the beginning of the software development phase. Once a hardware prototype is available the software development can continue on that platform. But before that a need for a model of the actual hardware is needed, hence some kind of emulator or simulator needs to be the developed to give the software developers a head start. The aim of this master thesis is to do a market survey of the available simulators for the ARM9E CPU and attached devices in a base- band chip and test their flexibility in terms of adding additional devices (both external and on chip), and also to implement a simulator using the C++ language. The goal is a modular structure for easy addition of certain components such as memory-interfaces, external devices etc. Another important part is the profiling of the executed code to instrument the execution in different ways, and efficiency to allow fast execution. The conclusion of the market study is that due to the high price of these simulators (1.5K€-40k€), we need to design our own simulator. Our simulator consists of different blocks; some of them are merely stubbed while others like the memory and CPU core are modelled more in detail. The performance of the simulator is around 200 KIPS due to the overhead in the debugging functionality. By removing the debugging overhead and optimizing the memory handling we could achieve at least 1 MIPS on the ARM execution and 5 MIPS on the Thumb execution.

<p>There is seemingly a never-ending consumer demand for mobileterminals such as cellular phones and personal digitalassistants (PDAs). Each new generation of terminals comes withmore elaborate functions than in the previous generation. Thistrend results in a higher performance demand on the computerarchitecture that performs the required computations within theterminal. To satisfy the projected requirements on cominggenerations of mobile terminals, we propose an architecturethat when intelligently managed can provide the necessaryperformance at low power and energy consumption. Thisarchitecture, a chip-multiprocessor (CMP), thus amulti-processor implemented on a single chip, has incombination with adaptive scheduling strategies the potentialto efficiently fullfill future requirements.</p><p>This licentiate thesis spans over several studies done onthe effectiveness of the adaptive CMP. In our studies, we haveshown that an adaptive CMP can satisfy the same performancerequirements as a comparable uni-processor, still consumingless power and energy. Furthermore, we have made an effort toaccurately model the workload behaviour of mobile terminals,which is of paramount importance when comparing candidatearchitectures. In the future, apart from proposing moreadaptive scheduling techniques, we expect to do more thoroughstudies on workload modeling as well as on the operating systeminfluence on the overall performance and power consumption.</p>

Avec l'introduction des standards de communication de quatrième génération (4G) dans la téléphonie mobile, les bandes de fréquence dans lesquelles un téléphone mobile générique doit fonctionner ont naturellement augmenté. Ces évolutions ont induit de nouveaux challenges techniques notamment en ce qui concerne la conception des modules d'émission-réception, du frontal RF mais surtout des antennes. Les bandes de fréquences nouvellement ajoutées, en particulier les bandes LTE 12/13/17 qui descendent jusqu’à 700 MHz, constituent le défi antennaire majeur: couvrir la bande basse des 700-960MHz (30%) notamment en incluant la bande GSM850/900 compte tenu de la rétrocompatibilité avec les standards 3G. Étant donné que l'espace réservé pour l'antenne dans un terminal portatif est électriquement petit (dans cette gamme de fréquences basses), des techniques de conception spécifiques doivent être mises en œuvre pour pouvoir couvrir toute la bande de fréquence basse. Dans la phase de conception, il doit également être pris en compte le fait que l'antenne ou les antennes puissent incorporer des techniques d'amélioration de débit de données telles que le MIMO (Multiple Input Multiple Output) et l’agrégation de porteuse (Carrier Aggregation) pour le LTE-Advanced. De plus, si l’on considère des cas d'utilisation réalistes, les effets de l'utilisateur (main, tête) sur les performances globales du terminal doivent aussi être examinés. Dans cette thèse, plusieurs concepts d'antennes 4G pour les futurs terminaux mobiles sont proposés. Différentes topologies antennaires sont évaluées notamment des antennes reconfigurables / passives ainsi que des structures à alimentation simples/multiples / With the introduction of the fourth generation (4G) of cellular mobile communications, there has been an increase in the frequency bands that a generic mobile phone should be able to operate. This requirement poses some challenges in the design of the transceiver modules of the device as well as the RF front-end and the antenna. From the antenna design point of view, the newly added frequency bands especially LTE bands 12-13-17 which goes down to 700MHz creates the main design challenge: covering 700-960MHz (30% bandwidth) in the low-band, considering also backward compatibility with the former technologies like GSM850/900. Since the space reserved for the antenna is electrically small in this frequency range, special design techniques are necessary to obtain the required bandwidth for a generic mobile terminal antenna. It should also be taken into account in the design phase, that the antenna needs to be appropriate for operation in the data-rate enhancement techniques like MIMO (multiple input multiple output) and carrier aggregation in LTE-Advanced. Furthermore, considering the real use cases of the mobile terminal, the effect of the user (hand, head and both) on the antenna performance should also be investigated. In this thesis, several antenna designs for 4G coverage in mobile terminals are proposed. Different antenna topologies are evaluated consisting of tunable/passive antennas as well as single/multi-feed structures.

There is seemingly a never-ending consumer demand for mobileterminals such as cellular phones and personal digitalassistants (PDAs). Each new generation of terminals comes withmore elaborate functions than in the previous generation. Thistrend results in a higher performance demand on the computerarchitecture that performs the required computations within theterminal. To satisfy the projected requirements on cominggenerations of mobile terminals, we propose an architecturethat when intelligently managed can provide the necessaryperformance at low power and energy consumption. Thisarchitecture, a chip-multiprocessor (CMP), thus amulti-processor implemented on a single chip, has incombination with adaptive scheduling strategies the potentialto efficiently fullfill future requirements. This licentiate thesis spans over several studies done onthe effectiveness of the adaptive CMP. In our studies, we haveshown that an adaptive CMP can satisfy the same performancerequirements as a comparable uni-processor, still consumingless power and energy. Furthermore, we have made an effort toaccurately model the workload behaviour of mobile terminals,which is of paramount importance when comparing candidatearchitectures. In the future, apart from proposing moreadaptive scheduling techniques, we expect to do more thoroughstudies on workload modeling as well as on the operating systeminfluence on the overall performance and power consumption.

No / This article presents a printed crescent-shaped monopole MIMO diversity antenna for wireless communications. The port-to-port isolation is increased by introducing an I-shaped conductor symmetrically between the two antenna elements and shaping the ground plane. Both the computed and experimental results confirm that the antenna possesses a wide impedance bandwidth of 54.5% across 1.6-2.8 GHz, with a reflection coefficient and mutual coupling better than -10 and -14 dB, respectively. By further validating the simulated and the measured radiation and MIMO characteristics including far-field, gain, envelope correlation and channel capacity loss, the results show that the antenna can offer effective MIMO/diversity operation to alleviate multipath environments.

This thesis is a study of multiple access schemes for satellite land mobile systems that provide a domestic or regional service to a large number of small terminals. Three orbit options are studied, namely the geostationary, elliptical (Molniya) and inclined circular orbits. These are investigated for various mobile applications and the choice of the Molniya orbit is justified for a U. K. system. Frequency, Time and Code Division Multiple Access (FDMA, TDMA and CDMA) are studied and their relative merits in the mobile environment are highlighted. A hybrid TDMA/FDMA structure is suggested for a large system. Reservation ALOHA schemes are appraised in a TDMA environment and an adaptive reservation multiple access protocol is proposed and analysed for a wide range of mobile communication traffic profiles. The system can cope with short and long data messages as well as voice calls. Various protocol options are presented and a target system having 100,000 users is considered. Analyses are presented for the steady state of protocols employing pure and slotted ALOHA and for the stabilty of the slotted variant, while simulation techniques were employed to validate the steady state analysis of the slotted ALOHA protocol and to analyse the stability problem of the pure ALOHA version. An innovative technique is put forward to integrate the reservation and the acquisition processes. It employs the geographical spread of the users to form part of the random delay in P-ALOHA. Finally an economic feasibility study is performed for the spacesegment. For costs of capital (r) less than 23 % the discounted payback period is less than the project's lifetime (10 years). At r- 8% the payback period is about 5.6 years, while the internal-rate-of-return is 22.2 %. The net present value at the end of the projects lifetime is £M 70 at r-8%.

No transporte de vídeo e áudio para aplicações de TV digital com recepção em terminais móveis podem ser utilizadas redes de distribuição de conteúdo baseadas em pacotes. Essas redes tornam o transporte dos sinais mais flexível. Entretanto, podem adicionar atrasos e variações de atraso, prejudicando o sincronismo dos fluxos de informação e, conseqüentemente, a apresentação das mídias. Nesta dissertação foi proposto um framework para avaliação e testes de sincronismo, desenvolvido para estudar a influência das perturbações causadas por redes de dados ou por remultiplexações no sincronismo de programas MPEG2. O framework possibilita o controle dos parâmetros de QoS da rede de distribuição utilizada para transmitir pacotes de um fluxo de transporte (MPEG2 Transport Stream) e permite avaliar a influência desses parâmetros no sincronismo do fluxo. Adicionalmente, foram implementados mecanismos de ressincronização do fluxo de transporte no framework, de forma a minimizar os efeitos dessas perturbações na rede. Verificou-se que os métodos implementados reduzem os efeitos de variações de atraso da rede e ressincronizam o fluxo de transporte transmitido, de forma que a variação de atraso nas amostras da referência de tempo do fluxo (Program Clock Reference . PCR) volta aos níveis anteriores (sem aplicação de variação de atraso na rede). / Content distribution packet networks can be used in video and audio transport for TV applications with reception in mobile terminals. These networks make signal transport more flexible. Nevertheless, they may add delay and jitter, damaging the synchronism of the information streams and, consequently, the media presentation. In this dissertation, a framework was proposed for synchronism test and evaluation. It was developed to study the influence of disturbances caused by data networks or remultiplexations in the synchronism of MPEG2 programs. The framework enables the control of QoS parameters of the distribution network used to transmit packets from a MPEG2 transport stream and allows the evaluation of the influence of these parameters in the synchronism of the streams. Furthermore, transport stream resynchronization mechanisms were implemented in the framework, minimizing the effects of these disturbances in the network. It was observed that the methods implemented reduce the effects of jitter in the network and resynchronize the transport stream transmitted, in a way that the jitter in the time reference samples (Program Clock Reference . PCR) of the stream returns to previous levels (without applying jitter in the network).

No transporte de vídeo e áudio para aplicações de TV digital com recepção em terminais móveis podem ser utilizadas redes de distribuição de conteúdo baseadas em pacotes. Essas redes tornam o transporte dos sinais mais flexível. Entretanto, podem adicionar atrasos e variações de atraso, prejudicando o sincronismo dos fluxos de informação e, conseqüentemente, a apresentação das mídias. Nesta dissertação foi proposto um framework para avaliação e testes de sincronismo, desenvolvido para estudar a influência das perturbações causadas por redes de dados ou por remultiplexações no sincronismo de programas MPEG2. O framework possibilita o controle dos parâmetros de QoS da rede de distribuição utilizada para transmitir pacotes de um fluxo de transporte (MPEG2 Transport Stream) e permite avaliar a influência desses parâmetros no sincronismo do fluxo. Adicionalmente, foram implementados mecanismos de ressincronização do fluxo de transporte no framework, de forma a minimizar os efeitos dessas perturbações na rede. Verificou-se que os métodos implementados reduzem os efeitos de variações de atraso da rede e ressincronizam o fluxo de transporte transmitido, de forma que a variação de atraso nas amostras da referência de tempo do fluxo (Program Clock Reference . PCR) volta aos níveis anteriores (sem aplicação de variação de atraso na rede). / Content distribution packet networks can be used in video and audio transport for TV applications with reception in mobile terminals. These networks make signal transport more flexible. Nevertheless, they may add delay and jitter, damaging the synchronism of the information streams and, consequently, the media presentation. In this dissertation, a framework was proposed for synchronism test and evaluation. It was developed to study the influence of disturbances caused by data networks or remultiplexations in the synchronism of MPEG2 programs. The framework enables the control of QoS parameters of the distribution network used to transmit packets from a MPEG2 transport stream and allows the evaluation of the influence of these parameters in the synchronism of the streams. Furthermore, transport stream resynchronization mechanisms were implemented in the framework, minimizing the effects of these disturbances in the network. It was observed that the methods implemented reduce the effects of jitter in the network and resynchronize the transport stream transmitted, in a way that the jitter in the time reference samples (Program Clock Reference . PCR) of the stream returns to previous levels (without applying jitter in the network).