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Packet Data Flow Control in Evolved WCDMA Networks / Flödeskontroll av Paketdata i Vidareutvecklade WCDMA NätverkBergström, Andreas January 2005 (has links)
The key idea of the new, shared high-capacity channel HSDPA, is to adapt the transmission rate to fast variations in the current radio conditions, thus enabling download peak data rates much higher than what WCDMA can offer today. This has induced a need for data that traverses the mobile network to be intermediately buffered in the Radio Base Station, RBS. A scheduling algorithm then basically selects the user with the most beneficial instantaneous radio conditions for access to the high-speed channel and transmission of its data over the air interface. The purpose of this thesis is to design a flow control algorithm for the transmission of data packets between the network node directly above the RBS, the RNC, and the RBS. This flow control algorithm should keep the level of the buffers in the RBS on such a level that the air interface may be fully utilized. Yet it is not desirable with large buffers since e.g., this induces longer round-trip times as well as loss of all data in the buffers whenever the user moves to another cell and a handover is performed. Theoretical argumentations and simulations show that both of these requirements may be met, even though it is a balancing act. Suggested is a control-theoretic framework in which the level in the RBS buffers are kept sufficiently large by taking into account predictions of future outflow over air and by using methods to compensate for outstanding data on the transport network. This makes it possible to keep the buffer levels stable and high enough to fully utilize the air interface. By using a more flexible adaptive control algorithm, it is shown possible to reach an even higher utilization of the air interface with the same or even lower buffering, which reduces the amount of data lost upon handovers. This loss is shown to be even more reduced by actively taking system messages about upcoming handover events into account as well.
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Uplink Interference Management of High Bit Rate Users in Evolved WCDMAAxelsson, Samuel January 2005 (has links)
The WCDMA air interface, used in the third generation mobile communication systems, is currently being evolved to improve the uplink, i.e. the radio links carrying traffic from the mobile user to the fixed network. An enhanced uplink concept is being developed to meet the expected needs from future applications like multimedia and video-streaming. This thesis studies interference management when high bit rates are introduced in the enhanced uplink. The study is performed through theoretical assessments and simulations using WCDMA system simulators. An optimization scheme using a basic system throughput based scheduling is derived to attain a theoretical assessment of bit rate limits. The throughput optimization is achieved at the expense of user-experienced fairness. Users located on cell coverage area overlap show to be most complicated to manage. The need for interference management is primary when the network deployment consists of small cells while coverage requirements are most essential when the cell size increases. By exploiting the benefits of directional antennas the antenna tilt can be tuned to increase performance resulting in increased bit rates, increased system throughput and increased resource efficiency. The improvements are attained without trade-offs and the different components of the study concur unanimously.
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Voice-over-IP over Enhanced Uplink / Kapacitet för IP-telefoni i den förbättrade WCDMA-upplänkenBrännström, Nils January 2007 (has links)
The traditional voice service in mobile networks is an important service that mobile users expect high quality from. With the convergence of mobile networks towards an all-IP network, an IP-based speech service becomes important which is referred to as Voice-over-IP (VoIP). The traditional voice service is highly optimized and a VoIP service must therefore fulfil strict quality requirements to provide the same speech service quality. The air interface technology, WCDMA, which is used in third generation communication systems in Europe is constantly developed. An improved concept for the mobile-to-network transmission, called the Enhanced Uplink (EUL) provides for higher uplink capacity for packet data services. It also includes features that may provide a sufficient VoIP service quality in mobile networks, when considering the uplink transmission. The purpose of this thesis is to evaluate the VoIP capacity over EUL and identify crucial aspects of radio resource management in order to increase the capacity. This is done through dynamic system simulations, using a realistic VoIP traffic model. The VoIP capacity is also estimated by a derived theoretical framework.\newline It is shown by simulation results and theoretical estimations, that power control is a vital mechanism in order to increase the capacity. Simulation results indicate that a VoIP over EUL capacity of 65\% of the traditional voice service capacity may be reached. The results also indicate that to improve the capacity for larger cells, the allowed VoIP packet delay must be increased.
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Analys av en meddelandetjänst vid krissituationer baserat på CBS-tekniken(Cell Broadcast Service)Nutti, Anders, Ekman, Mats January 2004 (has links)
Uppdragsgivare för detta examensarbete är Länsstyrelsen Dalarna. Målet är att undersöka hur lämplig tekniken med CBS (Cell Broadcast Service) baserade textmeddelande är vid viktigt meddelande till allmänheten (VMA-larm). En tjänst som utnyttjar CBS-tekniken kan rädda liv om allmänheten i ett tidigt skede får reda på vad som hänt och vart de ska bege sig.Rapporten visar på hur man kan använda SMS då en krissituation uppstår. Med hjälp av CBS-tekniken skickas meddelandet till specifikt valda basstationer och alla mobiltelefoner som är uppkopplade mot den. Det positiva är att bara de som behöver få veta vad som hänt får meddelandet.Enligt specifikationerna (ETSI) på GSM och 3G-näten i Sverige finns det stöd för utskick av CBS-meddelanden inbyggt i de befintliga näten. Det finns dock vissa problem vid införandet av CBS-tekniken i operatörsnäten. Operatörerna måste implementera en Cell Broadcast Center (CBC) i näten, denna del av infrastrukturen kommunicerar med basstationerna och sköter utskicken av CBS-meddelanden. Ett ytterligare problem med CBS-tekniken är att användarna måste aktivera mobiltelefonen för att ta emot CBS-meddelanden.Enligt Telia och Vodafone används CBS inte i Sverige idag men vi bedömer att tjänsten för att varna allmänheten kan använda sig av CBS-tekniken om den implementeras i operatörsnäten. Vi har i detta arbete använt oss av en generell kvalitativ metod kompletterat med Siegels metod. Med den kvalitativa metoden har vi intervjuat Telia och Vodafone på ingående fakta om CBS-tekniken. Vid design av teknisk lösning har vi använt oss av Siegels två första faser.
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Toward the 3G telecommunication system-The Analysis of Business Strategies of Telecommunication OperatorsHuang, Vincent 25 August 2003 (has links)
Abstract
Mobile phone is one essential communication product to most Taiwanese nowadays. As the market approaching its full capacity, service providers are now facing more competitions than ever. Some much lower profit and decreasing number of users can also be expected. Hence all the telecommunication service providers are trying to increase their revenue through providing mobile digital services to compensate the decreasing revenue from voice sector.
To be more precisely, telecommunication service providers are not solely telecomm operators after the integration with mobile data transfer. Mobile phone system is also changing from telecommunication system to a multifunctional mobile communication system.
3G (The 3rd Generation Mobile System) is the solution that meets new mobile communication requirements. The system is based in a new technology of wireless communication with a very high speed access to the Internet services. Mobility is the basic requirement of mobile networking service, the 3G system is enhancing the capability of mobile communication that allows us accessing the Internet, enjoying the multimedia entertainment, inquiring information, and doing mobile business anywhere.
3G is also giving the mobility to modern business activities. For instance, users can now accessing data, sharing interactive application software, and attending video conference through Internet and Intranet services. While users can now performing all these activities in anytime and place, the service boundaries between telecommunication, information, media, and entertainment will disappear. All these services will now be integrated, current fixed services will soon turn into mobile. We can watch video clips and receiving emails in the same time, also play on-line games with friends in any different corner around the world.
From 9.6Kbps to 2Mbps, the data transmission speed of 3G system is 40 times faster than GSM system. It may now take 2 minutes to send a multimedia message with a
photo and voice attachment, but in the future 3G system, it will be done within 5 minutes.
Nonetheless, the 3G system is not only providing high speed data transfer services, but also the convenience of accessing data. The core technology of 3G is packed Internet Protocol which allows users to get wired anytime. Emails can easily be downloaded to the mobile phone handset too. Just press one button, employees can easily get connected with their company. Service providers will charge only when the users are retrieving data from the Internet, otherwise all services are free.
The application of wireless services will be extended in the future. The needs of interaction between consumers and mobile equipment, also between one equipment and another will continue increasing. These interactions include system failure noticing, new order placing, or data transmitting. In addition to the telecommunication operators, businesses can also take good advantages of 3G to develop new applications. 3G will be a part of our life in the future.
The licenses of 3G operators have already been issued in February 2002. How firms can develop one successful business model of mobile strategy has already become the critical issue for these operators. This research is focusing on the reactions of telecommunication market after the introduction of 3G services. The research topics include exploring the technical problems of 3G system, analyzing the impact of current GPRS, i-mode, MMS, WLAN, PHS to the 3G system, also examining the attitudes of different governments in launching the 3G system in the global market. A conclusion remark will be made with the analysis of current operations of services providers and the future trend of the market.
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Mobile Network Operator Marketing Strategy ¡V The Comparison of 3G and WiMAX operational ModelKang, Hsiu-wei 20 July 2008 (has links)
WiMAX is a new mobile technology which provides high bandwidth and VoIP service. Therefore, WiMAX will bring effects to 3G telecom market. It is important that 3G telecom how to face WiMAX effects and WiMAX telecom how to enter the telecom market. Because WiMAX does not operate popularly and literatures usually only compare technology between WiMAX and 3G, this research discusses pricing strategy of the WiMAX and 3G.
This study discusses WiMAX and 3G based on MEC Model and Customer Differentiation Matrix, and uses price and platform of the MEC Model and customer valuation and customer need of the Customer Differentiation Matrix to discuss strategic position. This research uses case study to interview executive managers of the WiMAX and 3G telecoms. According to interview results and secondary data, this study concludes telecom strategic positions.
These results: (1) voice service will become mass market; (2) mobile value-added service will become important strategy; (3) WiMAX telecom will enter telecom market quickly; (4) WiMAX is not only a competitive role but also a complementary role; (5) mobile telecom will become personalized service. This conclusion discusses WiMAX and 3G positions according to marketing strategy. The telecom market will create new pricing strategy due to market competition after WiMAX enters telecom market.
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Uplink TDMA Potential in WCDMA SystemsPersson, Markus January 2008 (has links)
<p>The evolvement of the uplink in the third generation mobile telecommunication system is an ongoing process. The Enhanced Uplink (EUL) concept is being developed to meet the expected need from more advanced services, like video streaming and mobile broadband. One idea for further improvement in the EUL concept is to introduce Time Division Multiple Access (TDMA), which is studied in this master thesis.</p><p>The master thesis assignment is to study the consequences of introducing TDMA in EUL. The goal has been to identify the gains and problems, and how they can be handled. A derived theoretical framework and system simulations, using a radio network simulator, are used.</p><p>The overall conclusion is that there is a potentially large gain with an introduction of TDMA in EUL. Simulations in favorable conditions have shown that the system throughput can increase by 100% when there are only User Equipment (UE) that are using EUL in the system and by 50% when there is a mix of speech and EUL UE’s. When using TDMA the uplink load also shows improvements, the mean is generally higher but the variance is generally smaller.</p><p>Due to major differences in experienced interference between passive and active UE’s, the signal quality will vary a lot. The big variation in signal quality is identified as the main problem with introducing TDMA in EUL. It is shown that this problem can generate extreme high uplink load, which have a negative impact both on the resource efficiency and the coverage.</p>
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Μετάδοση δεδομένων σε κινητά δίκτυα επικοινωνιών 3ης γενιάς / Data tpransmission using third generation (3G) mobile networksΙγγλέσης, Ευάγγελος 16 May 2007 (has links)
Στόχος της παρούσας διπλωματικής εργασίας είναι η μελέτη της μετάδοσης δεδομένων πάνω από Κινητά Δίκτυα 3ης Γενιάς και συγκεκριμένα του δικτύου UMTS (Universal Mobile Telecommunications Systems). Την τελευταία δεκαετία τόσο η Κυψελωτή Κινητή Τηλεφωνία όσο και το Διαδίκτυο έχουν γνωρίσει τρομακτική εξάπλωση παγκοσμίως. Η ανάγκη του ανθρώπου για κινητικότητα από τη μια, και η ανάγκη για πρόσβαση σε πληροφορία και υπηρεσίες από την άλλη, οδήγησε στη σύγκλιση των δυο παραπάνω «κόσμων» μέσα από τα Κινητά Δίκτυα 3ης Γενιάς. Το δίκτυο UMTS, οδηγείται προς τη φιλοσοφία ενός all-IP δικτύου, που επιτρέπει πρόσβαση υψηλών ταχυτήτων στο Διαδίκτυο. Στην παρούσα διπλωματική εργασία παρουσιάζεται αναλυτικά η αρχιτεκτονική και λειτουργική δομή του UMTS δίκτυο, ξεκινώντας από τα γενικά χαρακτηριστικά του, σε ότι αφορά το χρησιμοποιούμενο φάσμα, την αξιοποίηση του διατιθέμενου εύρους ζώνης και τη δομή των κυψελών του UMTS. Στη συνέχεια παρουσιάζεται η αρχιτεκτονική του δικτύου, με αναφορά στον εξοπλισμό του χρήστη, το Δίκτυο Επίγειας Ασύρματης Πρόσβασης (UTRAN) και το Δίκτυο Κορμού (Core Network), ενώ παρουσιάζονται και τα πρωτόκολλα σηματοδοσίας και επιπέδου χρήστη εντός του UMTS. Στη συνέχεια η εργασία ασχολείται με το θέμα της παροχής Ποιότητας Υπηρεσίας (Quality of Service – QoS) στο δίκτυο UMTS. Παρουσιάζονται οι τάξεις QoS και τα χαρακτηριστικά τους στο UMTS, και οι παράμετροι που αυτές παίρνουν για συγκεκριμένες υπηρεσίες (φωνή, video, εφαρμογές ροής πολυμέσων κτλ.). Παράλληλα με την Ποιότητα Υπηρεσίας, παρουσιάζεται και η υπηρεσία MBMS (Multimedia Broadcast / Multicast Service) που έχει σχεδιαστεί για το UMTS δίκτυο και αναλύεται η δομή και ο τρόπος υλοποίησης των λειτουργιών της, οι διαδικασίες υπηρεσιών MBMS, οι παράμετροι που αυτή παίρνει και γίνεται και ανάλυση των επιμέρους λειτουργιών της. Το δεύτερο μέρος της εργασίας αφορά την πειραματική αξιολόγηση του δικτύου UMTS στον εξομοιωτή ns-2, σε ότι αφορά τη μετάδοση διαφορετικών ειδών κίνησης και την αποτελεσματικότητα των διαφορετικών πρωτοκόλλων. Αρχικά περιγράφεται ο τρόπος παραγωγής κίνησης για τον εξομοιωτή και των μεθόδων που χρησιμοποιήθηκαν προς την κατεύθυνση αυτή. Στη συνέχεια παρουσιάζονται τα αποτελέσματα των πειραμάτων για την απόδοση του πρωτοκόλλου TCP πάνω από το δίκτυο UMTS, και παρουσιάζονται τα προβλήματα που προκύπτουν στη χρήση του πρωτοκόλλου αυτού, κυρίως λόγο του υψηλού bit error rate που παρουσιάζεται στο ασύρματο κανάλι. Μελετώνται σενάρια χρήσης που χρησιμοποιούν τόσο UMTS DCH (Dedicated Channels), όσο και HSDPA (High Speed Downlink Packet Access) μεταδόσεις. Με σκοπό τη μελέτη της μετάδοσης και πολυμεσικού περιεχομένου πάνω από το UMTS, έγιναν αντίστοιχα πειράματα στον εξομοιωτή και διαπιστώθηκε η δυνατότητα του UMTS να εγγυηθεί τις διαφορετικές απαιτήσεις αυτού του είδους κίνησης (κυρίως σε ότι αφορά την καθυστέρηση των πακέτων) και τη «φιλική» προς το TCP πρωτόκολλο συνύπαρξη στο δίκτυο. Τέλος, στη διπλωματική αυτή εργασία προτείνεται ένα σχήμα, για την ανάπτυξη ενός συστήματος μετάδοσης πολυμεσικού περιεχομένου πάνω από UMTS, το οποίο λαμβάνει υπόψη του την τρέχουσα κατάσταση του δικτύου και προσαρμόζει τη ροή των πολυμεσικών δεδομένων σε αυτή. / The purpose of this dissertation is to study data transmission using Third Generation (3G) Mobile Networks and in particular using the Universal Mobile Telecommunications Systems (UMTS) network. Over the last decade, Cellular Mobile Telephony and Internet have spread rapidly worldwide. The need for mobility on the one side and on the other side the need for access to information and services, led to the convergence of the two worlds using Third Generation Mobile Networks. The UMTS network is slowly becoming an all-IP network that allows high speed data Internet connection. This dissertation discusses the UMTS network’s architectural and functional framework starting from the general characteristics of the available bandwidth and the UMTS cells’ structure. The architectural design of the network is presented next with respect to the user’s equipment, the Universal Terrestrial Radio Access Network (UTRAN) and the Core Network, followed by the signaling protocol and the user level within UMTS. After that, the dissertation covers Quality of Service (QoS) issues while using the UMTS network. The two QoS groups are presented along with their UMTS characteristics, and certain parameters for specific services (such as voice, video, multimedia streaming applications, etc.). In addition, the Multimedia Broadcast/Multicast Service (MBMS) is discussed. MBMS is a service designed for the UMTS network and the procedure and services of its functionality are being analysed. The second part of this dissertation deals with the experimental evaluation of the UMTS network in the ns-2 simulator, regarding the transmission of different types of traffic and the efficiency of the different protocols. The method of the traffic generation is being discussed at first, along with the implemented modules. Following that, the results from the experiments on TCP protocol performance over the UMTS air interface are being presented and some issues that raise up due to the high bit error rate that occur in the wireless channel are being discussed. In this case, we study the performance of both UMTS Dedicated Channels (DCH) and the High Speed Downlink Packet Access) transmissions. In order to study the transmission of multimedia content over the UMTS, some experiments took place, and showed that UMTS is able of guaranteeing the different requirements of this type of traffic, especially regarding the packets’ time delays and the friendly behavior against the TCP protocol, when coexisting in the network traffic load. Finally, this dissertation proposes a scheme for developing a multimedia content transmission system over UMTS, which takes into consideration the current state of the network and adapts the multimedia data stream to these conditions.
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Uplink TDMA Potential in WCDMA SystemsPersson, Markus January 2008 (has links)
The evolvement of the uplink in the third generation mobile telecommunication system is an ongoing process. The Enhanced Uplink (EUL) concept is being developed to meet the expected need from more advanced services, like video streaming and mobile broadband. One idea for further improvement in the EUL concept is to introduce Time Division Multiple Access (TDMA), which is studied in this master thesis. The master thesis assignment is to study the consequences of introducing TDMA in EUL. The goal has been to identify the gains and problems, and how they can be handled. A derived theoretical framework and system simulations, using a radio network simulator, are used. The overall conclusion is that there is a potentially large gain with an introduction of TDMA in EUL. Simulations in favorable conditions have shown that the system throughput can increase by 100% when there are only User Equipment (UE) that are using EUL in the system and by 50% when there is a mix of speech and EUL UE’s. When using TDMA the uplink load also shows improvements, the mean is generally higher but the variance is generally smaller. Due to major differences in experienced interference between passive and active UE’s, the signal quality will vary a lot. The big variation in signal quality is identified as the main problem with introducing TDMA in EUL. It is shown that this problem can generate extreme high uplink load, which have a negative impact both on the resource efficiency and the coverage.
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Hur kan Hi3G öka sitt genomslag på marknadenChohan, Norin, Quader, Bornita January 2005 (has links)
No description available.
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