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Towards efficient legacy test evaluations at Ericsson AB, LinköpingSterneberg, Karl Gustav January 2008 (has links)
3Gsim is a load generator for traffic simulation in a WCDMA (WidebandCode Division Multiple Access) network. It is developed at Ericsson AB inLinköping. Tests are run daily and the results are evaluated by testers. Whenerrors or abnormalities are found, the testers write trouble reports and thedescribed problems are handed over to designers whose task is to fix them.In order to save time, Ericsson wished to improve the efficiency.This study has focused on a specific part of the process of the developmentof 3Gsim, namely the process of evaluating test results. The goal has beento investigate if and how the process of evaluating 3Gsim test results can bemade more efficient.The daily work of the testers has been studied at close hand by the author.The testers answered a questionnaire with questions about their work andtheir opinions about the tools being used. The answers were evaluated andfocus was laid on the main problems.It was found that a lot of time is wasted on searching for trouble reports.A big part of the test result evaluation process consists of going throughsummary logs with error print-outs. Unfortunately no mapping betweenerror print-outs and trouble reports is performed. When going through thesummary logs the testers have to determine which errors have already beenreported and which ones that haven’t. Another major problem is the factthat most tests fail. On the webpage where the test results are displayed,this is indicated by a coloured field showing red. This is believed to have anegative effect on the work attitude.A lot of time can be saved by mapping error print-outs to trouble reportsand automatically comparing new error print-outs with old ones. The mappingwill also help preventing the creation of duplicated trouble reports. Thissolution will have the greatest impact on the improvement of the efficiency.Another way to enhance the efficiency is to develop a more advanced colourcoding scheme than the one used today. This coding scheme will help thetesters making the right priorities when processing the test results. Furthermore,these two solutions will have a positive effect on the work attitude. Aprototype implementing the first solution has been created. This prototypegives Ericsson AB the possibility to test the solution idea in practice.
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Mathematical Modelling of Call Admission Control in WCDMA NetworkHossain, Firoz, Sohab, Abu-Shadat-Mohammad January 2007 (has links)
WCDMA is an interference limited multiple access technique .It is widely used in the 3rd generation mobile networks like UMTS. When a new call arrives in the system to get admission, it checks whether the call is admitted or not based on some parameters like signal to interference ratio (SIR), transmission power of the Node B and the air interface load .If the call is accepted this will increase some interference to the ongoing calls. This new interference would degrade the ongoing calls and this will also add some extra load which may also lead to the exceeding capacity. So that the system has to decide this admission policy in a systematic way that all the users should maintain their communication with guaranteed quality of service. This decision making algorithm belongs to the radio resource management functionalities of the Radio Network Controller (RNC) in a WCDMA based UMTS network. This thesis paper focuses on the mathematical representation of the call admission control in an interference based environment. There is also a comparative study with different methods.
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Étude et optimisation de l'interaction processeurs-architectures reconfigurables dynamiquementFaten, Ben Abdallah 20 October 2009 (has links) (PDF)
Les applications de télécommunications mobiles et de multimédia, notamment dans le domaine de l'embarqué, deviennent de plus en plus complexes au niveau calculatoire et consomment de plus en plus d'énergie. Afin de palier aux besoins calculatoires et énergétiques de ces applications, les concepteurs se sont orientés vers les architectures hybrides, associant des systèmes de nature et paradigme différents. Ces architectures ont retenu l'attention des concepteurs parce qu'elles présentent un bon compromis coût/performances calculatoires d'autant plus qu'elles possèdent des propriétés énergétiques intéressantes. En outre, l'émergence dans la dernière décade des architectures reconfigurables dynamiquement associant haute performance et encore plus de flexibilité, a fait que les dernières générations des architectures hybrides associent un ou plusieurs processeurs à une ou plusieurs architectures reconfigurables dynamiquement (ARD). Cette thèse s'inscrit dans cette thématique et a ainsi pour objectif d'apporter une modélisation précise de ces architectures ainsi que des méthodologies permettant d'exploiter leurs potentiels de performances. Une modélisation des mécanismes d'échange d'informations entre un processeur couplé à une ressource reconfigurable est d'abord proposée ce qui a permis une identification précise de modèles de performances. En utilisant ces modèles de performances, une méthodologie d'adéquation algorithme architecture permettant suivant les paramètres de l'application de déterminer le couplage CPU/ARD adéquat est présentée. Nous introduisons ces modèles de performances dans le flot de développement logiciel de ces architectures afin de permettre un partitionnement temporel automatique basé sur la détermination de la surface (en nombre d'unités fonctionnelles) de l'ARD nécessaire pour avoir des performances optimales et ce en trouvant le facteur de déroulage de boucle qui assure le maximum de performances pour l'architecture hybride. Le dernier aspect de ce travail concerne la validation de ces méthodologies et leur mise en oeuvre. Nous présentons pour cela les mécanismes d'implémentation d'un démodulateur multimode DVB-T/H et d'un récepteur WCDMA dynamique sur une architecture hybride reconfigurable dynamiquement.
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Améliorations de l'accès paquet en sens montant du WCDMADimou, Konstantinos 18 December 2003 (has links) (PDF)
Les systèmes de 3G offrent de nouveaux services support (bearer services) à plus hauts débits pour les modes de transmission "paquet". Ces services vont coexister avec la voix (ou d'autres services temps réels), des scénarios de trafic mixte, voix et données, doivent être envisagés. La norme UMTS permet effectivement aux utilisateurs d'avoir plus d'un service activé simultanément. Les différentes classes de trafic augmentent la complexité de la gestion des ressources radios. Dans ce contexte, deux types de fonctions sont étudiés: l'allocation de TFCI et l'ordonnancement de paquets. Leur impact sur la qualité de service (QoS) ainsi que sur la capacité du système est évalué. On propose des améliorations de ces mécanismes dans le but d'augmenter la capacité du système et par conséquent d'améliorer la QoS des utilisateurs. Les études se restreignent au sens montant, c'est à dire aux transmissions du mobile (User Equipment ou UE) vers le réseau. Un premier mécanisme pour lequel un effort d'amélioration est fait, est l'adaptation du lien radio par variation du débit instantané transmis. On simule le cas d'une transmission multiservice (voix et données). L'UE doit partager un débit global qui lui est alloué entre les différents services activés. Ces derniers sont véhiculés dans des radio bearers (tuyaux supports). À chaque intervalle élémentaire de transmission (Transmission Time Interval, TTI), l'UE sélectionne un sous-débit pour chaque bearer; ceci se fait par la sélection d'un "format de transport" à appliquer pendant la durée TTI. Cette procédure s'effectue dans la couche MAC (Medium Access Control); le résultat de la sélection est une combinaison de formats de transport (Transport Format Combination, TFC) que la couche physique doit utiliser. La procédure, nommée sélection de TFC, permet d'adapter la transmission des différents services aux conditions variables de la propagation radio: elle détermine notablement la performance de transmission. L'algorithme de sélection de TFC est tracé dans ses grandes lignes dans la norme. Un de ses principes est de favoriser le trafic temps réel au détriment des services de données par paquet. Cependant, le trafic temps réel peut être perturbé par le trafic de données sous certaines conditions, en particulier pour les mobiles éloignés de la station de base (Node B). On propose un algorithme de sélection de TFC qui limite ces perturbations et qui offre une plus large zone de couverture aux services temps réels. En plus, il améliore la QoS du service de données et le débit effectif de l'UE sans augmenter sa puissance de transmission. Un autre type d'études concerne l'ordonnancement de paquets entre les différents utilisateurs ou UEs. C'est une procédure qui est contrôlée par la partie fixe du réseau. Nous l'étudions principalement par simulation en considérant divers mécanismes ou variations. Un premier mécanisme est nommé fast Variable Spreading Factor (fast VSF): les UEs distants changent rapidement leur facteur d'étalement (SF) afin de conserver une puissance de transmission constante, ce qui vise à stabiliser l'interférence inter-cellulaire. Un deuxième mécanisme étudié est un accès paquet décentralisé (decentralized mode) utilisant une information en retour sur le niveau global d'interférence dans la cellule. Un troisième mécanisme nommé "fast scheduling" (ordonnancement rapide) raccourcit le cycle d'ordonnancement. Les résultats ont montré que dans le cas de faible ou moyenne charge dans la cellule, le mode décentralisé réduit le délai par paquet jusqu'à 25 %. L'ordonnancement rapide augmente la capacité du système jusqu' à 10%. En plus, il améliore la QoS perçue par les utilisateurs en terme de débit par utilisateur et délai par paquet transmis.
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End-to-End Application Billing in 3G / End-to-End Application Billing in 3GChaudry, Kashif, Karadza, Elma January 2002 (has links)
<p>We have 3G on the doorstep but nothing seems to attract ordinary people to this technology. To attract the mass market the telecom industry must show something beyond high bit rates. They must show how ordinary people can take advantage of this new technology. This is done by showing the possibilities of the new technology and by demonstrating applications that it will handle. The telecom industry must convince the telecom operators to invest in this technology and the only thing that matters to them is how much revenue they can make by adopting the upcoming technology. </p><p>To convince the operators industry must show how the operators can charge for the new types of applications that will be introduced soon. This is the main reason why this Master's Thesis has been conducted. The purpose of this thesis is to provide a demonstration to Ericsson's 3G lab in Katrineholm in the form of an IP application with a billing solution. This thesis describes the migration from 1G to 3G and examines existing and future billing strategies as well. </p><p>The IP application is an application that uses progressive streaming in order to stream multimedia content to a PDA connected to a 3G phone. This application is platform independent because it is placed on leading Web servers, Apache and IIS. </p><p>The billing application consists of a number of steps. The first step is logging, which is performed by the Web server on which the streaming application is placed. The second step, processing and billing, is performed in the BGw, which is Ericsson's mediation tool, and the SQL server.The third step is displaying the bill, which is done by using ASP to create an active HTML page.</p>
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WCDMA Cell Load Control in a High-speed Train Scenario : Development of Proactive Load Control Strategies / Belastningsreglering av WCDMA celler i ett tågscenario : Utvecklings av strategier för proaktiv belastningsregleringJoshi, Raoul, Sundström, Per January 2012 (has links)
Load control design is one of the major cornerstones of radio resource management in today's UMTS networks. A WCDMA cell's ability to utilize available spectrum efficiently, maintain system stability and deliver minimum quality of service (QoS) requirements to in-cell users builds on the algorithms employed to manage the load. Admission control (AC) and congestion control (CC) are the two foremost techniques used for regulating the load, and differing environments will place varying requirements on the AC and CC schemes to optimize the QoS for the entire radio network. This thesis studies a real-life situation where cells are put under strenuous conditions, investigates the degrading effects a high-speed train has on the cell's ability to maintain acceptable levels of QoS, and proposes methods for mitigating these effects. The scenario is studied with regard to voice traffic where the limiting radio resource is downlink power. CC schemes that take levels of fairness into account between on-board train users and outdoor users are proposed and evaluated through simulation. Methods to anticipatorily adapt radio resource management (RRM) in a cell to prepare for a train is proposed and evaluated through simulation. A method to detect a high-speed train in a cell, and the users on it, is outlined and motivated but not simulated. Simulation results are promising but not conclusive. The suggested CC schemes show a surprising tendency towards an increase in congestion avoidance performance. Proactive RRM shows a significant increase in QoS for on-board users. No negative effects to users in the macro environment is noticed, with regard to the studied metrics.
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End-to-End Application Billing in 3G / End-to-End Application Billing in 3GChaudry, Kashif, Karadza, Elma January 2002 (has links)
We have 3G on the doorstep but nothing seems to attract ordinary people to this technology. To attract the mass market the telecom industry must show something beyond high bit rates. They must show how ordinary people can take advantage of this new technology. This is done by showing the possibilities of the new technology and by demonstrating applications that it will handle. The telecom industry must convince the telecom operators to invest in this technology and the only thing that matters to them is how much revenue they can make by adopting the upcoming technology. To convince the operators industry must show how the operators can charge for the new types of applications that will be introduced soon. This is the main reason why this Master's Thesis has been conducted. The purpose of this thesis is to provide a demonstration to Ericsson's 3G lab in Katrineholm in the form of an IP application with a billing solution. This thesis describes the migration from 1G to 3G and examines existing and future billing strategies as well. The IP application is an application that uses progressive streaming in order to stream multimedia content to a PDA connected to a 3G phone. This application is platform independent because it is placed on leading Web servers, Apache and IIS. The billing application consists of a number of steps. The first step is logging, which is performed by the Web server on which the streaming application is placed. The second step, processing and billing, is performed in the BGw, which is Ericsson's mediation tool, and the SQL server.The third step is displaying the bill, which is done by using ASP to create an active HTML page.
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WCDMA系統中配置OVSF碼滿足服務品質之研究 / OVSF Code Assignment Based QoS in WCDMA林淑瑩 Unknown Date (has links)
WCDMA是一個寬頻直接序列分碼多工存取(DS-CDMA)系統,使用正交可變展頻係數(Orthogonal Variable Spreading Factor,OVSF)碼以支援多樣化的資料傳輸速率,提供可變動位元速率和服務品質(Quality of Service,QoS)保障,以滿足使用者對多媒體應用服務的需求。在本研究中我們將訊務分群並配置符合的正交變數展頻係數碼的方式,來處理資源分配的問題,期讓每位使用者都能有滿意的服務品質。在論文中,為提供不同等級的差別服務以兼顧QoS和避免頻寬浪費,我們提出以動態群組配置的方式,從所有提出服務要求的訊務中,依其服務優先等級順序,挑選適合的訊務,將其放置於同一群組。系統會配置一OVSF碼給此群組,透過分時共用來進行資料傳輸,使其能提供多樣化的資料傳輸速率,減少碼阻斷,提高系統頻寬的使用率,並滿足使用者對服務品質的需求。實驗模擬顯示,本研究所提出的方法能提供多樣化的資料傳輸速率,並能有效減少碼阻斷,提高頻寬及系統使用率,並達到QoS的要求。 / WCDMA is a wideband Direct-Sequence Code Division Multiple Access (DS-CDMA) system, it uses Orthogonal Variable Spreading Factor (OVSF) codes to support diverse data transmission rates. Orthogonal variable spreading factor codes have the ability to provide variable bit rates and QoS to meet different multimedia application requirements. In this research, we group the traffic and use Orthogonal Variable Spreading Factor (OVSF) technique to deal with resource allocation problem in order to offer satisfactory quality of service to the users.
We propose dynamic group allocation method to provide differentiated services in order to meet the QoS requirement and avoid bandwidth wasting. From all those requested services, we move all those services of the same service priority to the same group. The system will subsequently assign OVSF code to each group. Data transmission of each group is based on time-sharing mechanism. Simulations show that the proposed method can provide diverse data transmission rates, and is able to reduce code blocking rate, increase bandwidth and system utilization, and meet the QoS requirement.
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Efficient CORDIC based implementation of selected signal processing algorithmsHeyne, Benjamin January 2008 (has links)
Zugl.: Dortmund, Techn. Univ., Diss., 2008
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Performance and Complexity Comparison of Doppler Spread Estimation for WCDMA SystemsPeng, Ziqi January 2014 (has links)
In cellular communication systems, the estimation of Doppler spread has a wide range of applications such as handoff, channel assignment scheme, adaptivetransmission, power control, etc. A great quantity of Doppler spread estimation algorithms have been proposed in the literature. But there has been few investigations which gives a comprehensive comparison of these algorithms. Therefore, it is of great signicance to compare and evaluate the performance of the existing algorithms in the same simulation framework. In this report, the uplink of WCDMA is considered. Four different types of Doppler spread estimation algorithms are evaluated and compared in a link level baseband simulator. The performance and the ability to implement are considered as the metrics for evaluation. Both Rayleigh and Rician fading channel model are applied, and the effect of speed, signal to noise ratio, Rician factor and the angle of arrived line of sight component are also tested. Moreover, the computational complexity is analysed to evaluate the practical value for implementation. / Estimatering av en mobils hastighet i form av Dopplerspridning har ett brett spektrum av tillmpningar i cellulra kommunikationssystem ssom fr yttningen avmobiler mellan celler, kanaltilldelningsschema, adaptiv sndning, eektstyrning,etc. En stor mngd algoritmer fr estimering av Dopplerspriding har frslagitsi litteraturen, men det r ovanligt med heltckande jmfrelser mellan med dessaalgoritmer. Drfr r det av stor betydelse att jmfra och utvrdera resultaten avbentliga algoritmer inom ramen fr samma simuleringsvertyg.I denna rapport anvnds upplnken fr WCDMA fr utvrdering av fyra olikatyper av algoritmer fr estimering av Dopplerspridning. Metriker fr utvrderingenr prestanda och implementeringsvnlighet. Bde Rayleigh och Rician fdningskanalmodeller har utvrderas, samt eekten av mobilens hastighet, signaltill brus frhllande, Rician faktor och infallsvinkel i ppet flt scenario. Dessutomhar den berkningsmssiga komplexiteten analyseras fr att utvrdera den praktiskaanvndbarheten i riktiga system.
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