<p>With today’s FPGA’s it’s possible to implement complete systems in a single FPGA. With help of Soft Processor Cores like the MicroBlaze processor several microcontrollers can be implemented in the same FPGA.</p><p>The third generation telecommunications system, cdma2000, has several channels, which has specific assignments. The Sync channel purpose is to attain initial time synchronization.</p><p>The purpose with this thesis has been to implement the Sync channel in a FPGA with use of a MicroBlaze processor. An evaluation of the concept of using a Soft Processor Core instead of ordinary DSP’s and microcontrollers would then be conducted.</p><p>This thesis has resulted in a system with a MicroBlaze processor that has the Sync channel as a peripheral. It’s possible to write information via HyperTerminal to the MicroBlaze processor which then uses this data as input to the Sync channel. The Sync channel then modulates the data according to the cdma2000 specifications and then outputs it onto an external pin at the FPGA.</p><p>The evaluation of this concept hasn’t resulted in a general recommendation whether to use ASIC or FPGA’s in a system. The concept of using Soft Processor Cores certainly has its benefits and is something that could be thought of in the future when designing a system.</p>

With today’s FPGA’s it’s possible to implement complete systems in a single FPGA. With help of Soft Processor Cores like the MicroBlaze processor several microcontrollers can be implemented in the same FPGA. The third generation telecommunications system, cdma2000, has several channels, which has specific assignments. The Sync channel purpose is to attain initial time synchronization. The purpose with this thesis has been to implement the Sync channel in a FPGA with use of a MicroBlaze processor. An evaluation of the concept of using a Soft Processor Core instead of ordinary DSP’s and microcontrollers would then be conducted. This thesis has resulted in a system with a MicroBlaze processor that has the Sync channel as a peripheral. It’s possible to write information via HyperTerminal to the MicroBlaze processor which then uses this data as input to the Sync channel. The Sync channel then modulates the data according to the cdma2000 specifications and then outputs it onto an external pin at the FPGA. The evaluation of this concept hasn’t resulted in a general recommendation whether to use ASIC or FPGA’s in a system. The concept of using Soft Processor Cores certainly has its benefits and is something that could be thought of in the future when designing a system.

Novas demandas por serviços de valor agregado têm surgido constantemente em sistemas de telefonia celular. Somente o tráfego de voz não tem sido mais suficiente para suprir as necessidades dos usuários, que hoje clamam também por serviços de dados que sejam rápidos, eficientes, baratos, com mobilidade e que atendam às mais diversas aplicações, como correio eletrônico, vídeo-conferência ou acesso à Internet. Este trabalho apresenta um método de determinação das taxas mínimas necessárias nos canais de tráfego para atender a essas aplicações. Utilizando-se da tecnologia CDMA2000, será feita uma análise do impacto na interface aérea da alocação dos canais de tráfego determinados. A mesma análise será feita nos casos em que se determinem taxas mínimas e/ou máximas alocadas para cada usuário, comparando-se também tempo necessário para a transmissão dos dados, eficiência na célula (taxa útil / taxa total transmitida), etc. As conclusões deste trabalho podem indicar estratégias para se atender aos usuários de serviços de dados em redes de telefonia móvel sob diferentes aspectos, como melhor relação custo-benefício, nichos específicos (concentrar-se em serviços que demandem maiores ou menores taxas de transmissão, por exemplo) ou até mesmo prever a quantidade de recursos de rede necessária para atender a uma determinada base de usuários. / Mobile telephony systems have been constantly asked for new demands of value added services. Voice traffic only is not enough anymore to support the new needs of mobile users because nowadays they ask for fast, cost-efficient, cheap and mobile services to support electronic mail, videoconference or Internet access. This work presents a method of how to determine minimum rates on traffic channels to support these services. Considering CDMA2000 technology, an impact analysis will be made in the air interface for these specific traffic channels. Same analysis will be made when minimum or maximum rates are reserved for each user, also comparing the time needed for data transmission, efficiency of the cell (useful rate / maximum rate) and others. The conclusions of this work may allow strategies to support data users in mobile telephony networks in such different ways, as better cost-effective solution, specific segment of the market (i.e., to concentrate in services with higher or lower transmission rates) or even to foresee the amount of resources needed in a network to support a forecasted number of users.

Novas demandas por serviços de valor agregado têm surgido constantemente em sistemas de telefonia celular. Somente o tráfego de voz não tem sido mais suficiente para suprir as necessidades dos usuários, que hoje clamam também por serviços de dados que sejam rápidos, eficientes, baratos, com mobilidade e que atendam às mais diversas aplicações, como correio eletrônico, vídeo-conferência ou acesso à Internet. Este trabalho apresenta um método de determinação das taxas mínimas necessárias nos canais de tráfego para atender a essas aplicações. Utilizando-se da tecnologia CDMA2000, será feita uma análise do impacto na interface aérea da alocação dos canais de tráfego determinados. A mesma análise será feita nos casos em que se determinem taxas mínimas e/ou máximas alocadas para cada usuário, comparando-se também tempo necessário para a transmissão dos dados, eficiência na célula (taxa útil / taxa total transmitida), etc. As conclusões deste trabalho podem indicar estratégias para se atender aos usuários de serviços de dados em redes de telefonia móvel sob diferentes aspectos, como melhor relação custo-benefício, nichos específicos (concentrar-se em serviços que demandem maiores ou menores taxas de transmissão, por exemplo) ou até mesmo prever a quantidade de recursos de rede necessária para atender a uma determinada base de usuários. / Mobile telephony systems have been constantly asked for new demands of value added services. Voice traffic only is not enough anymore to support the new needs of mobile users because nowadays they ask for fast, cost-efficient, cheap and mobile services to support electronic mail, videoconference or Internet access. This work presents a method of how to determine minimum rates on traffic channels to support these services. Considering CDMA2000 technology, an impact analysis will be made in the air interface for these specific traffic channels. Same analysis will be made when minimum or maximum rates are reserved for each user, also comparing the time needed for data transmission, efficiency of the cell (useful rate / maximum rate) and others. The conclusions of this work may allow strategies to support data users in mobile telephony networks in such different ways, as better cost-effective solution, specific segment of the market (i.e., to concentrate in services with higher or lower transmission rates) or even to foresee the amount of resources needed in a network to support a forecasted number of users.

Today’s wireless users expect great things from tomorrow’s wireless networks. These expectations have been fueled by hype about what the next generations of wireless networks will offer. The rapid increase of wireless subscribers increases the quality of services anytime, anywhere, and by any-media becoming indispensable. Integration of various networks such as CDMA2000 and wireless LAN into IP-based networks is required in these kinds of services, which further requires a seamless vertical handoff to 4th generation wireless networks. The proposed handoff algorithm between WLAN and CDMA2000 cellular network is implemented. The results of the simulation shows the behavior of the handoff and the time spent in WLAN or CDMA. The number of weak signal beacons determines whether a handoff is required or not. In this algorithm, traffic is classified into real-time and non real-time services.

The research reported in this thesis investigates the performance of the transport layer Stream Control Transfer Protocol (SCTP) for streaming video over CDMA2000 cellphone and data wireless networks. The main measure of performance was quality of the received video at a given buffer size, as cellphones have memory of limited capacity. The hypothesis was that SCTP would be able to improve the quality of streamed video over UDP under the same memory requirements. Our study involved two series of simulation experiments and measurements in a testbed on the Telecom NZ CDMA2000 network, to test the performance of video streaming under SCTP and under UDP. It was found that SCTP did not improve the quality in streamed video with up to 5 second buffers. While other scenarios that have been tested by other people with high packet loss or congestion have shown that SCTP can improve the quality, the CDMA2000 network does not suffer from the impairments that SCTP could neutralise, and because of that, in this scenario, the quality of video streaming under SCTP and UDP are similar. The complexity that SCTP adds does not correspond to an increase in quality.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Les séquences binaires pseudo-aléatoires sont couramment employées par les systèmes de transmissions numériques ou des mécanismes de chiffrement. On les retrouve en particulier dans les transmissions par étalement de spectre par séquence direct (e.g. 3G ou GPS)) ou pour construire des séquences d'apprentissage pour faciliter la synchronisation ou l'estimation du canal (e.g. LTE). Un point commun à toutes ces applications est la nécessité de se synchroniser avec la séquence émise. La méthode conventionnelle consiste à générer la même séquence au niveau du récepteur et la corréler avec le signal reçu. Si le résultat dépasse un seuil pré-défini, la synchronisation est déclarée acquise. On parle alors de détection par corrélation.Cette thèse aborde une autre voie : la détection des séquences binaires pseudo-aléatoire par des techniques de décodage canal. Ceci permet par exemple de détecter des séquences longues (e.g. de période 242), contrairement aux techniques par corrélation qui sont trop complexes à implémenter. Cela nécessite néanmoins que le récepteur connaisse au préalable le polynôme générateur de la séquence.Nous avons montré que le décodage d'une séquence pseudo-aléatoire est une problématique du type 'détecte et décode'. Le récepteur détecte la présence de la séquence et simultanément estime son état initial. Ceci correspond dans la théorie classique de la détection à un détecteur de type GLRT qui ne connaît pas la séquence émise, mais qui connaît sa méthode de construction. L'algorithme implémente alors un GLRT qui utilise un décodeur pour estimer la séquence reçue. Ce dernier est implémenté avec un algorithme de décodage par passage de messages qui utilise une matrice de parité particulière. Elle est construite avec des équations de parités différentes, chacune ayant un poids de Hamming valant t.Il correspond au nombre de variables participants à l'équation.Les équations de parité sont un constituant indispensable du décodeur. Nous avons donné leur nombre pour les m-séquences et les séquences de Gold. Pour le cas particulier des séquences de Gold, nous avons calculé le nombre d'équations de parité de poids t=5 lorsque le degré du polynôme générateur r est impair. Ce calcul est important car il n'y a pas d'équations de parité de poids t < 5 lorsque r est impair. Le nombre d'équations de parité est aussi utilisé pour estimer le degré minimal des équations d'un poids t donné. Nous avons montré que le modèle de prédiction estime correctement la valeur moyenne du degré minimal de l'ensemble des séquences de Gold. Nous avons néanmoins mis en évidence une grande variabilité du degré minimal des séquences autour de cette valeur moyenne.Nous avons ensuite identifié les ensembles absorbants complets de plus petite taille lorsque le décodeur emploie plusieurs polynômes de parité. Ces ensembles bloquent la convergence du décodeur lorsque celui-ci est alimenté avec du bruit. Ceci évite les fausses alarmes lors du processus de détection. Nous avons montré que des cycles 'transverses' détruisent ces ensembles absorbants, ce qui génère des fausses alarmes. Nous en avons déduit un algorithme qui minimise le nombre de cycles transverses de longueur 6 et 8, ce qui minimise la probabilité de fausse alarme lorsque le poids des équations de parité vaut t=3. Notre algorithme permet de sélectionner les équations de parité qui minimisent la probabilité de fausse alarme et ainsi réduire notablement le temps d'acquisition d'une séquence de Gold.Nous avons enfin proposé deux algorithmes de détection du code d'embrouillage pour les systèmes WCDMA et CDMA2000. Ils exploitent les propriétés des m-séquences constituant les séquences de Gold, ainsi que les mécanismes de décodage par passage de messages. Ces algorithmes montrent les vulnérabilités des transmissions par étalement de spectre. / Pseudo-random binary sequences are very common in wireless transmission systems and ciphering mechanisms. More specifically, they are used in direct sequence spread spectrum transmission systems like UMTS or GPS, or to construct preamble sequences for synchronization and channel estimation purpose like in LTE. It is always required to synchronize the receiver with the transmitted sequence. The usual way consists in correlating the received signal with a replica of the sequence. If the correlation exceeds a predefined threshold, the synchronization is declared valid.This thesis addresses a different approach: the binary sequence is detected with a forward error correction decoding algorithm. This allows for instance to detect very long sequences.In this thesis, we show that decoding a pseudo-random sequence is a problematic of the kind ‘detect and decode'. The decoder detects the presence of the transmitted sequence and simultaneously estimates its initial state. In conventional detection theory, this corresponds to a GLRT detector that uses a decoder to estimate the unknown parameter which is the transmitted sequence. For pseudo-random sequences, the decoder implements an iterative message-passing algorithm. It uses a parity check matrix to define the decoding graph on which the algorithm applies. Each parity check equation has a weight t, corresponding to the number of variables in the equation.Parity check equations are thus an essential component of the decoder. The decoding procedure is known to be sensitive to the weight t of the parity check equations. For m-sequences, the number of parity check equations is already known. It is given by the number of codewords of weight t of the corresponding Hamming dual code. For Gold sequences, the number of parity check equations of weight t = 3 and 4 has already been evaluated by Kasami. In this thesis we provide an analytical expression for the number of parity check equations of weight t = 5 when the degree of the generator polynomial r is odd. Knowing this number is important because there is no parity check equation of weight t < 5 when r is odd. This enumeration is also used to provide an estimation of the least degree of parity check equations of weight t.We have then addressed the problem of selecting the parity check equations used by the decoder. We observed the probability of false alarm is very sensitive to this selection. It is explained by the presence or absence of absorbing sets which block the convergence of the decoder when it is fed only with noise. These sets are known to be responsible for error floor of LDPC codes. We give a method to identify these sets according to the parity check equations used by the decoder. The probability of false alarm can increase dramatically if these absorbing sets are destroyed. Then we propose an algorithm for selecting these parity check equations. It relies on the minimization of the number of cycles of length 6 and 8. Simulation show that the algorithm allows to improve significantly the probability of false alarm and the average acquisition time.Eventually, we propose 2 algorithms for the detection of the scrambling codes used in the uplink of UMTS-FDD and CDMA2000 systems. They highlights a new vulnerability of DSSS transmission systems. It is now conceivable to detect these transmission if the sequence's generator is known.

With the deployment of 3G networks and gradual implementation of wireless networks, seamless handover between these wireless networks is becoming an increasingly desirable. mSCTP (Mobile Stream Control Transmission Protocol) is a new protocol developed from SCTP (Stream Control Transmission Protocol) to provide seamless handover based on IP networks. This thesis studies how to use this new protocol to handle handovers on transport level between CDMA2000 and WLAN networks. A survey of recently proposed and used mobility protocols is presented, comparing three common handover protocols operating on different layers: MIP (mobile IP) for the network layer, mSCTP for the transport layer and SIP (Session Initial Protocol) for the session layer. The results show mSCTP is the future for mobility support. Lastly, I will present a detailed procedure on how to set up handover testbed between CDMA2000 network and 802.11 WLAN based on mSCTP and the results show that the handover performed between these two networks is fast and smooth but it is affected by the signal strength of the CDMA2000.

The interest in the development of wireless high-speed data services is in response to the strong market demand for high-speed wireless Internet access. Current standards aim at delivering a peak data rate greater than 2Mbps on the forward link. Since data services and voice services are fundamentally different, new concepts were introduced in the design of the forward data channel. In addition, methods of evaluating the performance of a cellular CDMA system have to be revisited. This thesis proposes a method which can be used to find the forward link peak and average data rates, throughput and coverage of a cellular CDMA system which is capable of delivering high-speed wireless data. A summary of changes in design philosophy and recent advances in technologies which enable high-speed wireless data delivery are presented. The proposed method takes into account major aspects commonly found in the forward data channel and applies the generalized Shannon capacity formula for multi-element antenna (MEA) systems. The analysis focuses on the physical layer and is flexible enough to be adapted to various propagation environments, antenna configurations, multicode allocations, user distributions and cell site configurations. Sample numerical results for various multicode allocations are shown using a system model with two-tier interfering cells with one transmit antenna and two receive antennas operating under a frequency selective slow fading channel with propagation environment described by the Recommendation ITU-R M. 1225 indoor office, outdoor to indoor and pedestrian and vehicular test environments. Different transmit / receive antenna configurations and multicode allocations and their impact on the average data rate is also explored.