Efficient radio resource management is of paramount importance for achieving the high bit rates targeted by the 3GPP for the 3GPP Long-Term Evolution. The radio air interface must be able to provide both high peak bit rates and acceptable cell-edge bit rates. This thesis therefore investigates three methods which try to combine the peak bit rate of a reuse-1 system with the cell-edge bit rate of a reuse-3 system in an OFDM-based downlink. These methods are soft frequency reuse, reuse partitioning and one variation of soft frequency reuse, reuse-1 with prioritization. In static simulations with one user per cell and a system load of 100 percent, a Shannon capacity gain of up to 18 percent at the 10th percentile is shown with reuse partitioning compared to a reuse-1 system. This gain comes coupled with a loss of only 5 percent at the median. Soft frequency reuse is also investigated statically and shows a 13 percent gain at the 10th percentile compared to a reuse-1 system. Having a lower 10th percentile gain than reuse partitioning, it also shows a slightly smaller loss of 4 percent at the median and a much smaller loss at the 90th percentile. Dynamic simulations with a traffic model and multiple users per cell offer a more realistic scenario and show that the proposed intercell interference management methods do not provide the same throughput gains in the dynamic case at low system loads. If interference is not an issue, interference coordination is still costly in terms of limiting bandwidth and/or decreasing the scheduling gain, but provides no significant interference reduction. At low system loads, reuse-1 is therefore the best scheme although interference coordination might prove necessary to provide edge-user throughput at high loads. For such purposes, soft frequency reuse is shown to be a potential candidate and although not investigated in a dynamic setting, reuse partitioning is believed to have similar performance. The traffic model chosen in this thesis only allows study of low system loads but at these loads, soft frequency reuse performs promisingly close to a reuse-1 system.

A mobile phone antenna with a radiating coupling feed is presented. By using the radiating coupling feed, the conventional coupled-fed loop antenna and coupled-fed shorted monopole antenna can be efficiently incorporated into the antenna structure and respectively excite a wide band resonant mode to cover GSM850/900 and GSM1800/1900/UMTS/LTE2300/2500 for the seven-band operation. Besides, the antenna can be in compact integration with the extended ground plane such that more electronic components in the mobile phone can be accommodated in the practical applications. In order to study the near-field radiation characteristics of the antenna, SAR and HAC are also simulated and analyzed.

An internal eight-band LTE/WWAN handset antenna integrated with a USB connector is presented. The proposed antenna comprises an antenna ground which faces a protruded ground extended from the main ground of the handset to accommodate a USB connector. The antenna ground is used as a shorting portion to short-circuit the antenna to ground such that the coupling between the antenna ground and the protruded ground is effectively suppressed. In this case, the proposed antenna can be integrated with a USB connector mounted on the protruded ground, leading to compact integration of the antenna inside the handset. Good radiation characteristics of the antenna are also obtained, and the proposed antenna occupies 60 ¡Ñ 12 ¡Ñ 4.8 mm3 (about 3.4 cm3) only. Effects of the user¡¦s head and hand on the proposed antenna are studied, and the simulated SAR and HAC results are also analyzed in this thesis.

In this thesis, two types of handset antenna design respectively for dual-band GSM850/1900 operation and seven¡Vband LTE/WWAN operation are presented. The proposed antennas can achieve decreased antenna size and enhanced operating bandwidth by shaping the system ground plane of the handset. The seven-band LTE/WWAN antenna is printed on the system circuit board with good radiation characteristics and occupies a small size of 24.5 x 10 mm2. At first, we propose a half-loop antenna structure which integrates its facing edge of the system ground plane as the resonant path of the antenna. In this case, the required length of the half-loop antenna structure is only about a half compared with the traditional loop antenna. Next, to enhance the operating bandwidth of the antenna, a parasitic shorted monopole strip is added and a shaped system circuit board is used. The shaped system circuit board can integrate the battery with the circuit board to help reduce the thickness of handset. Also, much enhanced operating bandwidth for the lower band can be obtained, owing to the enhanced surface current excitation in the system ground plane resulting from properly shaping the system circuit board. Effects of the user¡¦s head and hand on the proposed antenna are studied, and the simulated SAR and HAC results are also analyzed for bio-compatibility issue.

In this dissertation, novel printed multiband antennas for slim mobile communication devices are presented. The design techniques on achieving decreased antenna size and enhanced operating bandwidth in different shaped system ground planes with the antennas printed thereon are proposed. At first, a WWAN antenna integrated with a U-shaped ground plane is presented. Two techniques are applied to achieve WWAN operation with a small antenna size. The first technique is to embed load a proper chip inductor at a proper position in the shorted strip monopole of the antenna. The second one is to use a band-stop matching circuit disposed on the main circuit board of the handset. For the second and third antenna designs, owing to the C-shaped ground plane, much enhanced operating bandwidth for their lower band can be obtained. The second antenna design can cover the LTE/WWAN eight-band operation without increasing the size of the antenna by using a reconfigurable circuit element. The third antenna design integrated with a battery element and a metal midplate for practical application to help reduce the thickness and enhance the robustness of handset. The antenna can cover seven-band LTE/WWAN operation with good radiation characteristics and occupy a small size of 35 x 8 mm2. Finally, the simulated SAR and HAC results are analyzed for bio-compatibility consideration.

The advanced signal processing systems of today require extreme data throughput and low power consumption. The only way to accomplish this is to use parallel processor architecture. The aim of this thesis was to evaluate the use of parallel processor architecture in baseband signal processing. This has been done by implementing three demanding algorithms in LTE on Ambric Am2000 family Massively Parallel Processor Array (MPPA). The Ambric chip is evaluated in terms of computational performance, efficiency of the development tools, algorithm and I/O mapping. Implementations of Matrix Multiplication, FFT and Block Interleaver were performed. The implementation of algorithms shows that high level of parallelism can be achieved in MPPA especially on complex algorithms like FFT and Matrix multiplication. Different mappings of the algorithms are compared to see which best fit the architecture.

Among the multimedia content distribution services to the handheld receivers, mobile TV is a popular service. Digital Video Broadcast (DVB) networks have high capacity and coverage to perform a mass multimedia content distribution. The conventional DVB networks are designed to cover fixed receivers, which have a roof antenna. The handheld receivers have different configurations which cause weaker link budgets. Generally, a broadcast system is unidirectional and it does not have a feedback channel to ensure the reception of the data at the receiver side. On the other hand, cellular networks have more reliable bidirectional links with the handheld receivers. Individual multimedia transmission to each handheld receiver generates a huge load in the cellular networks. In the specific example of mobile TV, it is not efficient to regenerate the same transmission load for each handheld receiver. In our thesis work, we consider a cooperation between the broadcast systems and the cellular networks for an efficient multimedia reception at the handheld receivers. We use the cellular network link for the retransmission of the lost packets from a multimedia broadcast data-flow reception. In this work we analyze the coverage for handheld receivers in a single frequency broadcast network. We specifically consider several outdoor and indoor scenarios in a DVB-T2 network. We analyze how a data flow is processed in DVB-T2 and propose a scheme for the identification of packets in the DVB transmission. The core contribution of our thesis work is the proposition of a Real-time Flow Repair (RFR) Service based on cellular network, which repairs any multimedia data-flow to the handheld receivers in real-time. The proposed RFR service is based on a light client-server application protocol, namely Constrained Application Protocol (CoAP). The RFR proposal is also supported by the analysis of the load generated in LTE Radio access network due to RFR service.

Cet exposé analyse les perspectives large bande des réseaux PMR, à travers l'évaluation du candidat LTE, et la proposition d'une possible évolution du codage canal, la solution brevetée des codes turbo à protection non uniforme. Une première étude dans le chapitre 2 se concentre sur l'analyse multi-couche et l'identification des problèmes clé des communications de voix et de vidéo sur un réseau LTE professionnel. Les capacités voix et vidéo sont estimées pour les liens montant et descendant de la transmission LTE, et l'efficacité spectrale de la voix en lien descendant est comparée à celle de PMR et GSM. Ce chapitre souligne certains points clé de l'évolution de LTE. S'ils étaient pas résolus par la suite, LTE se verrait perdre de sa crédibilité en tant que candidat à l'évolution de la PMR. Une telle caractéristique clé des réseaux PMR est le codage canal à protection non uniforme, qui pourrait être adapté au système LTE pour une évolution aux contraintes de la sécurité publique. Le chapitre 3 introduit cette proposition d'évolution, qui a été brevetée: les turbo codes à protection non uniforme intégrée. Nous proposons une nouvelle approche pour le codage canal à protection non uniforme à travers les codes turbo progressives hiérarchiques. Les configurations parallèles et séries sont analysées. Les mécanismes de protection non uniformes sont intégrés dans la structure de l'encodeur même à travers l'insertion progressif et hiérarchique de nouvelles données de l'utilisateur. Le turbo décodage est modifié pour exploiter de façon optimale l'insertion progressive de données dans le processus d'encodage et estimer hiérarchiquement ces données. Les propriétés des structures parallèles et séries sont analysées à l'aide d'une analogie aux codes pilotes, ainsi qu'en regardant de plus près leurs caractéristiques de poids de codage. Le taux de transmission virtuel et les représentations des graphs factor fournissent une meilleure compréhension de ces propriétés. Les gains de codage sont évalués à l'aide de simulations numériques, en supposant des canaux de transmission radio statiques et dynamiques, et en utilisant des codes de référence. Enfin, dans le chapitre 4, l'idée breveté du code turbo parallal progressif et hiérarchique (PPHTC) est évaluée sur la plateforme LTE. Une description détaillée de l'architecture des bearers de LTE est donnée, et ses conséquences sont discutées. Le nouveau codage canal est inséré et évalué sur cette plateforme, et ses performances sont comparées avec des schémas de transmission typique à LTE. L'analyse de la qualité de la voix aide à conclure sur l'efficacité de la solution proposée dans un système de transmission réel. Pourtant, même si cette dernière donne les meilleurs résultats, d'avantage d'optimisations devraient être envisagées pour obtenir des gains améliorés et mieux exploiter le potentiel du codage proposé. L'exposé se conclut dans le chapitre 5 et une courte discussion présente les futures perspectives de recherche

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This thesis is dedicated to the study of the OFDM/OQAM modulation as an alternative to the OFDM modulation. We treat more especially the multi-user environment. In this respect, synchronization aspects are crucial. The different options plus the choice of the waveform are examined in this point of view. Another objective is to precisely show how the OFDM/OQAM can be adapted to a cellular transmission type, taking as reference the 3GPP/LTE system. The main contributions we have made are : 1) Analysis of the desynchronization phenomena : we analyze the effect of desynchronization, according to the time and frequency axes, on the performance of OFDM/OQAM at the receiver side. 2) Synchronization method : we analyze a method of temporal synchronization defined in a single user OFDM/OQAM transmission and we adapt it to a multi-user scenario type. 3) Proposing for a multiple access scheme : we propose a multiple access scheme based on theOFDM/OQAM modulation, alternative to the known techniques OFDMA and SC-FDMA, for the UL transmission in a 3GPP/LTE context.