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Design & development of an HSPA system simulator for network planningMatinrad, Arash January 2011 (has links)
HSPA planning requires identification of key performance indicators (KPIs), such as infrastructure cost,performance, service quality and the amount of E/M pollution. To evaluate such a framework describing and linking these key elements for HSPA planning and optimization we need to carry out a set of HSPA system-level event-driven simulations under different scenarios. To have such simulations, a new tool should be developed. In this thesis work a simulation tool is developed within NS-3, an open source network simulator. The simulation tool consists several entities to represent a UMTS network and respective nodes in it, and necessary procedures to form a network dynamically. A simple base station removal algorithm in a system level, is developed focusing on the reduction of capital expenditure (CAPEX) of a network. The algorithm defines a cost function in order to remove the most costly base station from network preserving the target coverage percentage. Baseline results show that the simulation tool is working properly and later the results from algorithm indicate that, it is possible to use the algorithm within a dynamic simulation.
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Energy consumption reduction mechanisms in mobile networks / Mécanismes de réduction de la consommation d'énergie dans les réseaux mobilesSaker, Louai 02 December 2011 (has links)
La consommation en énergie des réseaux de télécommunications a suscité un intérêt grandissant au cours des dernières années et les opérateurs mobiles cherchent des solutions innovantes pour optimiser l’efficacité énergétique. Dans cette thèse, nous nous focaliserons sur les schémas d’optimisation de la consommation d’énergie des réseaux d’accès mobiles. Nous commençons par étudier la stratégie de partage de charge qui minimise la consommation d’énergie dans la cellule tout en limitant l’impact sur la Qualité de Service. Le gain obtenu par ces algorithmes de gestion des ressources radio reste cependant limité; ceci est dû au fait que la consommation d’énergie ne dépend pas que de la charge, mais comporte une importante partie constante. Pour obtenir un gain plus important, nous proposons la mise en veille de certaines ressources du réseaux aux heures creuses où le trafic est faible, ce qui mène à des gains substantiels. Nous proposons ensuite un contrôleur de gestion de la mise en veille qui choisit l’action optimale en fonction de l’état du réseau. En effet, l’activation d’une nouvelle ressource n’est pas instantanée et un effet ping-pong peut apparaitre suite aux commandes simultanées d’activation/désactivation des ressources. Nous adaptons nos contrôleurs afin de prendre en compte ces imperfections, et nous montrons comment déduire la politique optimale. Nous étudions ensuite le cas de déploiement de petites cellules dans des réseaux hétérogènes et montrons que leur efficacité énergétique est améliorée par rapport au réseau purement macro-cellulaire, pourvu que la consommation d’énergie de petites cellules reste faible. Nous proposons ensuite un contrôleur optimal qui active/désactive les petites cellules en se basant sur des informations de trafic et de localisation des usagers. Nous considérons différents cas de figure avec une information complète, partielle ou retardée et montrons que ces schémas de mise en veille permettent d’atteindre d’importants gains de consommation d’énergie / In the recent years, more importance has been given to the energy consumption issue in telecommunication networks and mobile operators are rethinking their network design for optimizing its energy efficiency. In this thesis, we propose schemes for optimizing the energy consumption of mobile access networks. We begin by proposing energy-aware Radio Resource Management (RRM) schemes and show that a load balancing between available resources gives some energy savings. However, these gains remain small as a large part of the energy consumption is load-independent. We thus propose sleep mode schemes of resources in the network (cells or carriers) and show that they give a large gain when traffic is low. We then propose optimal sleep mode controllers that give, for each traffic scenario, the best actions to take in each state of the network. We make two observations: the first is that activating a new resource is not instantaneous, leading to QoS degradation if a conservative policy is not considered, and the second is that a ping-pong effect may appear at the frontier between two capacity regions. We adapt our controllers to take into account these imperfections, and show how to derive the optimal policy using Markov decision theory. We then extend our works to the case of small cell deployment in heterogeneous networks, composed of macro and small cells base stations. We study the capacity and power consumption of these networks and show that the energy efficiency is increased for some deployment strategies when the power consumption of small cells is low. We then propose sleep mode for small cells and develop optimal sleep/wakeup schemes based on the information on traffic load and user localization in the cell, in the cases where this information is complete, partial or delayed. We show that these sleep mode schemes achieve large energy consumption gains
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Análise de tráfego de redes 3G/HSPAMelo, Emilio Honorio de 31 January 2010 (has links)
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Previous issue date: 2010 / Nos últimos anos, as operadoras de telefonia móvel estão investindo na implantação e expansão de suas redes de terceira geração 3G/HSPA. O volume de tráfego de dados dessas redes crescem a taxas elevadas, o que demanda altos investimentos e celeridade no incremento por mais capacidade, exigindo das operadoras a racionalização de seus recursos, para garantir um grau de serviço adequado aos seus clientes e o aprimoramento no conhecimento dessas redes.
Atualmente, este processo de racionalização é norteado por métricas tradicionais geradas pelos sistemas de gerenciamento e monitoramento de rede das operadoras (Operation SubSystem - OSS). Porém, o conhecimento da composição do tráfego de dados na rede 3G pode oferecer maiores detalhes e informações complementares para ações de dimensionamento e aferições da rede e o planejamento de políticas para os seus usuários de uma maneira mais precisa. No entanto, o potencial das informações extraídas de amostras de tráfego de pacotes na rede 3G ainda não foi devidamente investigado.
Este trabalho objetiva realizar uma análise do comportamento de tais redes, através de coleta de dados numa interface IuPS e também de medições disponíveis no OSS de uma operadora móvel comercial brasileira.
A partir dessa análise, fornecemos meios de se conhecer o perfil de seus usuários e um conjunto de métricas que proporcionem um melhor entendimento de seu funcionamento.
Tais métricas assumem um papel de destaque nas tomadas de decisões gerenciais nas áreas técnica e comercial
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Turbo Equalization for HSPA / Turboutjämning för HSPAKonuskan, Cagatay January 2010 (has links)
<p>New high quality mobile telecommunication services are offered everyday and the demand for higher data rates is continuously increasing. To maximize the uplink throughput in HSPA when transmission is propagated through a dispersive channel causing self-interference, equalizers are used. One interesting solution, where the equalizer and decoder exchange information in an iterative way, for improving the equalizer performance is Turbo equalization.</p><p>In this thesis a literature survey has been performed on Turbo equalization methods and a chosen method has been implemented for the uplink HSPA standard to evaluate the performance in heavily dispersive channels. The selected algorithm has been adapted for multiple receiving antennas, oversampled processing and HARQ retransmissions. The results derived from the computer based link simulations show that the implemented algorithm provide a gain of approximately 0.5 dB when performing up to 7 Turbo equalization iterations. Gains up to 1 dB have been obtained by disabling power control, not using retransmission combining and utilizing a single receiver antenna. The algorithm has also been evaluated considering alternative dispersive channels, Log-MAP decoding, different code rates, number of Turbo equalization iterations and number of Turbo decoding iterations.</p><p>The simulation results do not motivate a real implementation of the chosen algorithm considering the increased computational complexity and small gain achieved in a full featured receiver system. Further studies are needed before concluding the HSPA uplink Turbo equalization approach.</p>
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Turbo Equalization for HSPA / Turboutjämning för HSPAKonuskan, Cagatay January 2010 (has links)
New high quality mobile telecommunication services are offered everyday and the demand for higher data rates is continuously increasing. To maximize the uplink throughput in HSPA when transmission is propagated through a dispersive channel causing self-interference, equalizers are used. One interesting solution, where the equalizer and decoder exchange information in an iterative way, for improving the equalizer performance is Turbo equalization. In this thesis a literature survey has been performed on Turbo equalization methods and a chosen method has been implemented for the uplink HSPA standard to evaluate the performance in heavily dispersive channels. The selected algorithm has been adapted for multiple receiving antennas, oversampled processing and HARQ retransmissions. The results derived from the computer based link simulations show that the implemented algorithm provide a gain of approximately 0.5 dB when performing up to 7 Turbo equalization iterations. Gains up to 1 dB have been obtained by disabling power control, not using retransmission combining and utilizing a single receiver antenna. The algorithm has also been evaluated considering alternative dispersive channels, Log-MAP decoding, different code rates, number of Turbo equalization iterations and number of Turbo decoding iterations. The simulation results do not motivate a real implementation of the chosen algorithm considering the increased computational complexity and small gain achieved in a full featured receiver system. Further studies are needed before concluding the HSPA uplink Turbo equalization approach.
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Έλεγχος ισχύος κατά τη μετάδοση πολυμεσικών δεδομένων σε κινητά δίκτυα επικοινωνιών επόμενης γενιάςΡέκκας, Ευάγγελος 27 April 2009 (has links)
Ο ταχύτατα εξελισσόμενος τομέας των δικτύων κινητών επικοινωνιών έχει επιφέρει μία ιδιαίτερα
αυξανόμενη απαίτηση για ασύρματη, πολυμεσική επικοινωνία. Στη ραγδαία εξέλιξη του τομέα αυτού
συμβάλουν τα μέγιστα και οι απαιτήσεις της σύγχρονης αγοράς για ένα ενοποιημένο και λειτουργικό
σύστημα κινητής τηλεφωνίας παρέχοντας παράλληλα πληθώρα ευρυζωνικών υπηρεσιών ψηφιακού
περιεχομένου στους πελάτες – χρήστες του.
Είναι γεγονός ότι, τα τελευταία χρόνια τα δίκτυα επικοινωνιών τρίτης γενιάς (3G) – UMTS γνωρίζουν
μεγάλη άνθηση και η χρήση τους έχει επεκταθεί στις περισσότερες ευρωπαϊκές χώρες, όπως και στην
Ελλάδα. Τα νέα αυτά κινητά δίκτυα αντικαθιστούν τα υπάρχοντα κινητά δίκτυα δεύτερης γενιάς και
επιπλέον προσφέρουν προηγμένες υπηρεσίες στους κινητούς χρήστες. Ωστόσο, η αδήριτη ανάγκη για
μεγαλύτερες (ευρυζωνικές) ταχύτητες πρόσβασης οδήγησε στην περαιτέρω ανάπτυξη των 3G δικτύων
και στην υιοθέτηση νέων τεχνολογιών, με κυριότερο εκπρόσωπο τους την τεχνολογία HSPA. Η
τεχνολογία HSPA αποτελεί τη φυσιολογική μετεξέλιξη του UMTS, η οποία πολλές φορές συναντάται και
ως 3.5G ή 3G+, προκειμένου να δηλώσει την αναβάθμιση του 3G (UMTS) προτύπου.
Ωστόσο, παρά το γεγονός ότι η τεχνολογία HSPA αναμένεται να προσφέρει τη δυνατότητα παροχής
πληθώρας ευρυζωνικών υπηρεσιών, το 3GPP ήδη μελετά και επεξεργάζεται νέες τεχνολογίες που θα
επικρατήσουν την αμέσως επόμενη δεκαετία στην αγορά των κινητών επικοινωνιών. Το νέο αυτό project
αποκαλείται Long Term Evolution (LTE) και στοχεύει στην επίτευξη ακόμη υψηλότερων ρυθμών
μετάδοσης σε συνδυασμό με την αξιοποίηση μεγαλύτερου εύρος ζώνης. Κύρια προοπτική του LTE
αποτελεί η διασφάλιση της ανταγωνιστικότητας και η επικράτηση του προτύπου στο χρονικό ορίζοντα
της επόμενης δεκαετίας.
Κατά συνέπεια, η αγορά κινητών επικοινωνιών σταδιακά μεταλλάσσεται προς τη δημιουργία δικτύων
κινητών επικοινωνιών επόμενης γενιάς, με απώτερο σκοπό την επίτευξη του αποκαλούμενου «Mobile
Broadband».
Ταυτόχρονα με την εκτεταμένη εξάπλωση των δικτύων κινητών επικοινωνιών επόμενης γενιάς καθώς
και τις αυξημένες δυνατότητες των κινητών συσκευών, οι πάροχοι πολυμεσικού περιεχομένου και
υπηρεσιών ενδιαφέρονται όλο και περισσότερο για την υποστήριξη της πολυεκπομπής δεδομένων
(multicasting) στα δίκτυα αυτά με σκοπό την αποτελεσματική διαχείριση και επαναχρησιμοποίηση των
διαθέσιμων πόρων του δικτύου. Επιπρόσθετα, οι χρήστες των κινητών δικτύων έχουν πλέον την
απαίτηση να προσπελαύνουν εφαρμογές και υπηρεσίες οι οποίες μέχρι σήμερα μπορούσαν να
διατεθούν αποκλειστικά από τα συμβατικά ενσύρματα δίκτυα. Έτσι λοιπόν στις μέρες μας γίνεται λόγος
για υπηρεσίες πραγματικού χρόνου όπως mobile TV, mobile gaming, mobile streaming κ.α.
Ένα από τα σημαντικότερα βήματα των δικτύων κινητών επικοινωνιών προς την κατεύθυνση της
παροχής νέων, προηγμένων πολυμεσικών υπηρεσιών είναι η εισαγωγή της υπηρεσίας Multimedia
Broadcast / Multicast Service (MBMS). Η MBMS υπηρεσία έχει σαν κύριο σκοπό την υποστήριξη IP
εφαρμογών πανεκπομπής (broadcact) και πολυεκπομπής (multicast) επιτρέποντας με αυτό τον τρόπο
την παροχή υπηρεσιών υψηλού ρυθμού μετάδοσης σε πολλαπλούς χρήστες με οικονομικό τρόπο. Η
multicast μετάδοση δεδομένων σε κινητά δίκτυα επικοινωνιών είναι μια νέα λειτουργικότητα η οποία
βρίσκεται ακόμη στο στάδιο των δοκιμών και της προτυποποίησης της. Ένας multicast μηχανισμός
μεταδίδει τα δεδομένα μόνο μία φορά πάνω από κάθε ασύρματο σύνδεσμο που αποτελεί τμήμα των
μονοπατιών προς τους προορισμούς-κινητούς χρήστες.
Το κρισιμότερο σημείο που εντοπίζεται κατά τη multicast μετάδοση δεδομένων στα κινητά δίκτυα
επικοινωνιών είναι ο αποτελεσματικός έλεγχος ισχύος. Οι σταθμοί βάσης των κυψελωτών αυτών
δικτύων διαθέτουν περιορισμένους πόρους ισχύος (άρα και περιορισμένη χωρητικότητα κυψέλης),
γεγονός που επιβάλλει τη χρήση μίας βέλτιστης στρατηγικής για την όσο το δυνατόν καλύτερη
αξιοποίηση των διαθέσιμων πόρων ισχύος. Ο έλεγχος ισχύος στοχεύει στη μείωση της εκπεμπόμενης
ισχύος, στην ελαχιστοποίηση του θορύβου στο κυψελωτό δίκτυο και κατά συνέπεια στη διασφάλιση
μεγαλύτερης χωρητικότητας επιπλέον χρηστών.
Ένα από τα βασικότερα στοιχεία του ελέγχου ισχύος στα δίκτυα κινητών επικοινωνιών επόμενης γενιάς
κατά τη multicast μετάδοση πολυμεσικών δεδομένων αποτελεί η επιλογή του κατάλληλου καναλιού
μεταφοράς για τη μετάδοση των δεδομένων από τον κόμβο RNC στον κινητό χρήστη. Συγκεκριμένα,
πρόκειται για ένα κρίσιμο ζήτημα το οποίο είναι ακόμα υπό εξέταση στο 3GPP. Προς την κατεύθυνση
αυτή, στο MBMS στάνταρ έχει αναπτυχθεί ένας μηχανισμός που αποκαλείται Counting Mechanism. Ο στόχος του μηχανισμού αυτού είναι η βελτιστοποίηση της ροής δεδομένων για την υπηρεσία MBMS,
όταν αυτά διέρχονται από τις διεπαφές του UTRAN (διεπαφές Iub και Uu). Ωστόσο, η υπάρχουσα
μορφή του μηχανισμού αυτού διακρίνεται από πολλές αδυναμίες που δεν επιτρέπουν την
αποτελεσματική και μαζική μετάδοση πολυμεσικών δεδομένων. Τα σημαντικότερα προβλήματα του
υπάρχοντος Counting Mechanism είναι η απουσία ευρυζωνικών χαρακτηριστικών καθώς και η σπατάλη
σημαντικού τμήματος των (ούτως ή άλλως περιορισμένων) πόρων ισχύος. Εν γένει, η επιλογή του
κατάλληλου καναλιού μεταφοράς των πολυμεσικών δεδομένων στο ασύρματο μέσο είναι μια δύσκολη
διαδικασία καθώς μια λανθασμένη επιλογή καναλιού μπορεί να οδηγήσει στην αστοχία ενός ολόκληρου
κελιού. Γίνεται σαφές, λοιπόν, ότι απαιτείται μία βελτιωμένη έκδοση του υπάρχοντος Counting
Mechanism για την αποτελεσματικότερη και οικονομικότερη μετάδοση πολυμεσικού περιεχομένου σε
μεγάλο πλήθος χρηστών.
Στόχος της παρούσας μεταπτυχιακής εργασίας είναι η μελέτη του ελέγχου ισχύος στα δίκτυα κινητών
επικοινωνιών επόμενης γενιάς καθώς και η ανάπτυξη νέων μεθόδων για τη βελτιστοποίηση του
Counting Mechanism. Ιδιαίτερο χαρακτηριστικό της μεταπτυχιακής αυτής εργασίας είναι η ενσωμάτωση
και η «εκμετάλλευση» όλων των ιδιαίτερων χαρακτηριστικών της HSDPA τεχνολογίας στην MBMS
υπηρεσία. Η MBMS υπηρεσία μέχρι τώρα βασίζεται στη λειτουργικότητα των υπαρχόντων UMTS
δικτύων. Ο συνδυασμός των δύο αυτών προτύπων, δηλαδή του MBMS και του HSDPA, υπόσχεται
τόσο την παροχή ευρυζωνικών πολυμεσικών δεδομένων σε μεγάλο πλήθος κινητών χρηστών όσο και
τη βέλτιστη επίτευξη ελέγχου ισχύος.
Προς αυτή την κατεύθυνση, θα πραγματοποιηθεί ανάλυση όλων των υπαρχόντων καναλιών μεταφοράς
του UMTS καθώς και της τεχνολογίας HSDPA και τα οποία μπορούν να χρησιμοποιηθούν για τη
multicast μετάδοση πολυμεσικών δεδομένων. Πιο συγκεκριμένα, τα κανάλια τα οποία αξιολογούνται
είναι τα: Forward Access Channel, High Speed–Downlink Shared Channel και Dedicated Channel. Τα
παραπάνω κανάλια μεταφοράς αξιολογούνται με βάση την απαιτούμενη ισχύ που πρέπει να ανατεθεί
από το σταθμό βάσης για καθένα από αυτά, και κατά συνέπεια με βάση το ρυθμό μετάδοσης τους, τον
αριθμό των χρηστών που μπορούν να εξυπηρετήσουν, την ποιότητα υπηρεσιών για κάθε χρήστη, τη
μέγιστη δυνατή κάλυψη της κυψέλης κ.α.
Επίσης, αντικείμενο της παρούσας μεταπτυχιακής εργασίας είναι η εύρεση ενός κατάλληλου σημείου
εναλλαγής μεταξύ των διάφορων τύπων καναλιών κατά τη μετάδοση πολυμεσικών δεδομένων. Θα
διερευνηθούν τεχνικές μείωσης της εκπεμπόμενης ισχύος με απώτερο σκοπό την αποδοτικότερη χρήση
των πόρων του συστήματος και θα προταθούν νέες παραλλαγές του Counting Mechanism με ανώτερα
χαρακτηριστικά διαχείρισης και κατανομής πόρων ισχύος. Οι νέοι αυτοί μηχανισμοί υπόσχονται
βελτιωμένη απόδοση, μείωση της καταναλισκόμενης ισχύος και κατά συνέπεια αύξηση της
χωρητικότητας των κινητών δικτύων επόμενης γενιάς. Το γεγονός αυτό μπορεί να επιτρέψει τη μαζική
μετάδοση πολυμεσικών δεδομένων σε πληθώρα κινητών χρηστών.
Τέλος, θα διερευνηθούν και νέες, πιο αποδοτικές τεχνικές για τη μετάδοση πολυμεσικών δεδομένων στα
μελλοντικά δίκτυα LTE. Στην περίπτωση αυτή λαμβάνονται υπόψιν όλες οι βασικές τεχνικές μετάδοσης
δεδομένων όπως τα MIMO κεραιοσυστήματα. / Due to rapid growth of mobile communications technology, the demand for wireless multimedia
communications thrives in today’s consumer and corporate market. The need to evolve multimedia
applications and services is at a critical point given the proliferation and integration of wireless systems.
Consequently, there is a great interest in using the IP-based networks to provide multimedia services.
One of the most important areas in which the issues are being debated, is the development of standards
for the Universal Mobile Telecommunications System (UMTS).
UMTS constitutes the third generation (3G) of cellular wireless networks which aims to provide highspeed
data access along with real time voice calls. Wireless data is one of the major boosters of
wireless communications and one of the main motivations of the next generation standards. Through the
3G mobile networks, the mobile users have the opportunity to run applications and realize services that
offered until today only by wired networks. Such broadband services are mobile Internet, mobile TV,
mobile gaming, mobile streaming, video calls etc.
High Speed Packet Access (HSPA) constitutes a significant step towards the so-called Mobile
Broadband. HSPA supports both downlink and uplink communication through the HSDPA and HSUPA
channels, respectively. HSPA promises the provision of enhanced end-users’ experience with a wide
range of novel, interactive applications, faster performance and reduced delays. Furthermore, from the
operators’ prism, HSPA ensures improved network performance, increased capacity and higher
coverage.
Multimedia Broadcast Multicast Service (MBMS) is a novel framework, extending the existing UMTS
infrastructure that constitutes a significant step towards the so-called Mobile Broadband. MBMS is
intended to efficiently use network and radio resources, both in the core network and, most importantly,
in the air interface of UMTS Terrestrial Radio Access Network (UTRAN), where the bottleneck is placed
to a large group of users. Actually, MBMS is a point-to-multipoint service in which data is transmitted
from a single source entity to multiple destinations, allowing the networks resources to be shared.
MBMS is an efficient way to support the plethora of the emerging wireless multimedia and application
services such as IP Video Conferencing, Streaming Video by supporting both broadcast and multicast
transmission modes.
Long Term Evolution (LTE) will stretch the performance of 3G systems with improved coverage and
system capacity, as well as increased data rates and reduced latency. LTE also provides a tight
integration between unicast and multicast/broadcast MBMS transport bearers. Moreover, it also takes
3G-MBMS one step further to provide highly efficient multi-cell broadcast. By transmitting not only
identical signals from multiple cell sites (with identical coding and modulation), but also synchronize the
transmission timing between cells, the signal at the mobile terminal will appear exactly as a signal
transmitted from a single cell site and subject to multi-path propagation.
There is a growing demand for wireless data applications, which although face low penetration today,
are expected to gain high interest in future mobile networks. These applications actually reflect a
modern, future way of communication among mobile users. For instance, mobile TV is expected to be a
‘killer’ application for 3G’s. Such mobile TV services include streaming live TV (news, weather forecasts
etc.) and streaming video (such as video clips). All the above constitute a series of some indicative
emerging applications that necessitate advanced transmission techniques. However, increased
improvements have to be made both in the uplink and downlink transmission and in better radio
resource management, in order to meet future demands and provide rich multimedia services to large
users’ population. In addition, several obstacles, mainly regarding the interoperability and ubiquitous
access between different access technologies and services, have to be overcome (thus leading to 4G).
The main target of this dissertation is the study of power control issues, the development and the
performance evaluation of an efficient power scheme for the provision of broadband, multicast services
and applications to mobile users. This will be effectively implemented through the efficient use of MBMS
and HSPA technologies in both 3G and its evolution LTE. An important aspect of this work is the
investigation of the selection of the most efficient radio bearer for the transmission of MBMS multicast
data. MBMS services can be provided in each cell by either multiple Point to Point (PTP) channels or by
a single Point to Multipoint (PTM) channel. PTM transmission uses a single channel reaching down to
the cell edge, which conveys identical traffic. On the other hand, PTP transmission uses dedicated
channel allocated to each user, which conveys identical content. Obviously, a decision has to be made on the threshold between these two approaches. Therefore, improvements of the currently existing
Counting Mechanism in MBMS will be studied. Although relative research work in this field considers the
need for a power-based Counting Mechanism and not a UE-based Counting Mechanism, the case of
HSDPA usage in such a power mechanism could be further investigated, taking also into account the
availability of multi-mode cells. This could lead to an optimal scheme for the MBMS Counting
Mechanism.
The fundamental selection criterion of channel type is the amount of base station power required to
transmit to a group of users. To this direction, the role of power control in the MBMS multicast
transmission in UMTS is studied and analysed. A power control scheme for the efficient radio bearer
selection in MBMS is then proposed. The choice of the most efficient transport channel in terms of
power consumption is a key point for the MBMS since a wrong transport channel selection for the
transmission of the MBMS data could result to a significant decrease in the total capacity of the system.
Various UMTS transport channels are examined for the transmission of the multicast data and a new
algorithm is proposed for the more efficient usage of power resources in the base station.
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Podpora služeb reálného času v současných mobilních sítích třetí generace / Support of real-time services in recent 3G mobile networksVinkler, Lukáš January 2009 (has links)
This Master’s thesis is focused on the recent 3G mobile networks. The first chapter describes an evolution of standardization 3G and surveys a gradual development of 3G networks in Czech Republic from a point of view of commercially launched technologies and assigned frequency spectrums for single mobile operators. UMTS and CDMA 2000 are briefly approached in next subchapters. The subchapter CDMA 2000 is briefly concentrated on architecture and a physical layer of this technology and characterizes main features of four revises of developmental branch CDMA 2000 1x EV-DO. The subchapter UMTS is especially focused on a comparison of air interfaces TD-CDMA and W-CDMA. New features were implemented to the recent system UMTS for a better support of real-time services. These features increasing a throughput and decreasing a delay are described in a chapter Technology HSPA. This chapter chooses the most important features and describes changes (in a control and architecture) which had to be implemented. First chapter is finished by technology WiMAX. The most recent perspective cell systems are compared with WiMAX in this subchapter and qualitative parameters of WiMAX are shown there. The three different 3G technologies (UMTS-FDD, UMTS-TDD and CDMA 2000) are lunched in Czech Republic. The second chapter briefly compares coverage of three czech mobile operators (Telefónica O2, T-Mobile and U:fon) and then presents results of qualitative parameters of used 3G technologies. The simulation conducted by software IxChariot were focused on to gauge parameters like throughput, delay, jitter, lost data, MLR and DF. The conditions for providing real-time services were specified based on simulations that were practically checked. The lab composed in last chapter should bring closer to students technology UMTS-TDD launched by T-Mobile. The students will measure the qualitative parameters of this technology with the assistance of commonly available tools.
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Impact Of Transmission Patterns On One-Way Delay In 3G Networks Of SwedenKrishna, Vamsi, Dasari, Praveen January 2012 (has links)
Over the last few years, there has been a signifi cant rise in the mobile broadband users worldwide. Recently, operators around the world have been improving the 3G networks by providing Dual Carrier-High Speed Packet Access+ (DC-HSPA+) services in both uplink and downlink to the users. However, the delay performance of the operational DC-HSPA+ networks is not focused. Firstly, we investigate and analyze the e ffect of operator service on One-Way Delay (OWD) and Jitter. Secondly, we investigate the treatment of protocols by 3G network for random packet sizes and random Inter Packet Duration (IPD). Thirdly, we investigate the eff ect of background load on OWD for packets generated at very low rate. Fourthly, we investigate the impact of constant IPD and streaming. Fifthly, we investigate the effects of shrinking the interval of IPD on OWD in 3G networks. Lastly, we investigate the OWD for Constant-Bit-Rate (CBR) and Variable-Bit-Rate (VBR) transmission patterns. Firstly, results show that OWD in the DC-HSPA+ networks is lower compared to the OWD in the preceding HSUPA networks and OWD strongly depends on packet-size at lower rates. Secondly, the 3G networks treat User Datagram Protocol (UDP), Transmission Control Protocol (TCP) and Internet Control Message Protocol (ICMP) protocols similarly for random packet size and random IPD. Thirdly, at high rates OWD depends on E-TFCE-DCH Transport Format Combination (ETFC) grants. Thirdly, the results also indicate that background load has a signi ficant impact on the end-to-end OWD. Fourthly, for low rates, OWD depends on packet sizes and for high rates OWD depends on IPD and for higher rates, OWD depends on E-TFC grants. Fifthly, we also observe: Shrinking the interval of IPD does not necessarily improve the OWD performance. Lastly, results also indicate that the VBR pattern has a better OWD performance than the CBR pattern for low transmission rates.
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Predi??o de s?ries temporais de par?metros de redes HSPA - WCDMABezerra, Tiago dos Santos 10 June 2014 (has links)
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Previous issue date: 2014-06-10 / Com o crescimento da demanda de tr?fego de dados nas redes de terceira
gera??o (3G), as operadoras de telefonia m?vel t?m atentado para o direcionamento dos
recursos em infraestrutura nos locais onde se identifica maior necessidade. O
direcionamento desses investimentos tem o objetivo de manter a qualidade do servi?o
prestada principalmente em regi?es urbanas densas. Neste trabalho ? realizada a
predi??o de s?ries temporais em rede WCDMA - HSPA dos par?metros Rx Power,
RSCP (Received Signal Code Power), Ec/Io (Energy per chip/Interference) e taxa de
transmiss?o (throughput) na camada f?sica. A coleta dos valores dos par?metros foi
realizada numa rede em pleno funcionamento atrav?s de um drive test na cidade de
Natal ? RN, uma capital do nordeste brasileiro. Os modelos utilizados para predi??es
das s?ries temporais foram os de Alisamento Exponencial Simples, Holt, Holt-Winters
Aditivo e Holt-Winters Multiplicativo. O objetivo das predi??es das s?ries temporais ?
verificar qual modelo ir? gerar as melhores predi??es dos par?metros da rede WCDMA
- HSPA. / With the growing demand of data traffic in the networks of third generation
(3G), the mobile operators have attempted to focus resources on infrastructure in places
where it identifies a greater need. The channeling investments aim to maintain the
quality of service especially in dense urban areas. WCDMA - HSPA parameters Rx
Power, RSCP (Received Signal Code Power), Ec/Io (Energy per chip/Interference) and
transmission rate (throughput) at the physical layer are analyzed. In this work the
prediction of time series on HSPA network is performed. The collection of values of the
parameters was performed on a fully operational network through a drive test in Natal -
RN, a capital city of Brazil northeastern. The models used for prediction of time series
were the Simple Exponential Smoothing, Holt, Holt Winters Additive and Holt Winters
Multiplicative. The objective of the predictions of the series is to check which model
will generate the best predictions of network parameters WCDMA - HSPA.
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Vývoj a výhled mobilního připojení v ČR / Development and Future Prospects of Mobile Internet Connection in the Czech RepublicBičík, Petr January 2008 (has links)
Mobile telecommunications belong to one of the fields which still evolves and it is expected that in the future they are going to offer great benefit to the whole world. This work focuses on current and future development of mobile Internet connection in the Czech Republic. At first the technologies used to provide mobile Internet connection are described and compared and then the situation (in terms of technologies and mobile operators) in the Czech market is outlined and its possible evolution in the near future is presented. Furthermore, the tarifs of mobile operators are compared with those in place two years ago. The strengths and weaknesses of the current mobile Internet connection are evaluated based on the conducted questionnaire survey. The latest results are then analyzed and compared with the results from a previous survey conducted in 2007 as part of a bachelor's thesis, which has been further extended in this mater's thesis.
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