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Planificación de sistemas UMTS mediante sistemas de información geográficaKhalil Hassan Alghamri, Mohammed 31 July 2008 (has links)
En esta Tesis Doctoral se lleva a cabo un análisis de las redes celulares de Tercera Generación basadas en WCDMA desde el punto de vista de planificación y estimación de capacidad.
En la planificación tradicional debido al excesivo uso de campañas de medidas, esto hace que el coste sea muy elevado. En esta tesis se ha realizado un modelo de planificación de sistemas UMTS mediante sistemas de información geográfica (ARC/INFO) potente que provee una base de datos geográfica adaptable y capaz de hacer todo tipo de tareas sobre esta información utilizando mapas digitales que reflejan el estado real del entorno en el área a planificar. El hecho de elegir el ARC/INFO, un Sistema de Información Geográfica potente para nuestra aplicación de planificación de sistemas celulares, es por sus grandes ventajas y su sencillez de uso sobre sistemas operativos robustas como el Unix.
Este modelo de planificación utiliza modelos de propagación que dan buen margen de la predicción de las perdidas de propagación que tienen en cuenta los edificios y las calles del entorno urbano, así los resultados tendrán más precisión a la hora de planificación.
La planificación radio en UMTS tiene por finalidad realizar los cálculos de cobertura y capacidad, con objeto de optimizar el despliegue de las estaciones bases y así cumplir los objetivos de calidad de servicio establecidos por el operador. En esta tesis se ha analizado en general los factores más importantes que afectan a la capacidad y en especial se ha estudiado en más detalles el efecto del coeficiente de correlación entre estaciones bases sobre la capacidad de los sistemas UMTS en entornos urbanos. / Khalil Hassan Alghamri, M. (2005). Planificación de sistemas UMTS mediante sistemas de información geográfica [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/2902 / Palancia
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Objektivní analýza dat získaných během měření kvality signálu / Objective analysis of data obtained during quality of service measurementsDopita, Michal January 2017 (has links)
This thesis is focused on objective analysis of data obtained during quality of service measurements provided by the company O2 Czech Republic Inc. Purpose of this study is mapping of existing methods, resources and ways of measurement. The result of practical part is design of new methodology of measurement for the department RAN Management, which is responsible for measurement of quality of services.
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Modelování řízeného využití síťových zdrojů v sítích UMTS / Modelling of UMTS network resource controlBednárik, Ján January 2009 (has links)
The main aim of my master thesis was to get acquainted with the implementation of quality-of-service support methods in UMTS 3G mobile network and the evaluation of these methods in a simulation environment with main interest in the characteristic features of the traffic classes. The impact of the QoS methods available on different service types were verified in the OPNET Modeler simulation environment. I examined mainly the potentials of the model to support the required quality parameters for the connections. The models of typical network applications, available in real UMTS networks, together with two examples of mobile networks, operating voice and video services in combination with standard data services, were defined in this simulation environment. My work also contains the detailed description of configuration parameters fundamental for correct behavior of the simulation models. The simulation also shows the case, when the transport service is rejected due to the lack of network resources. The key parameters of the model are also described and their effect on the service quality with and without QoS control are compared in separate scenarios. Finally, I investigated the effect of mobility of the end stations on the communication process, especially on the duration of a file transmission.
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A pre-emption framework for UMTS satellite system supporting multimedia trafficPillai, Anju, Hu, Yim Fun, Halliwell, Rosemary A. 10 June 2014 (has links)
Yes / The pre-emption procedure is an important part of the Radio Resource Management (RRM) when dealing with the emergency traffic. It allows resources to be allocated to higher priority connections by pre-empting lower priority connections. The provision of the pre-emption mechanism becomes much more important in the case of satellite systems
such as the Inmarsat Broadband Global Area Network (BGAN) system which aids in providing the communication during a catastrophe. This paper focuses on the preemption framework for a UMTS based satellite systems. Three algorithms have been proposed, Greedy, SubSetSum and Fuzzy pre-emption algorithm. Extensive simulations are carried out for the three algorithms and their performances are compared against each other. Simulation results show that the Fuzzy pre-emption algorithm performs better than the other two algorithms. / European Space Agency/Inmarsat
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Ultra Wideband Interference on Third-Generation Wireless NetworksNader, Gustavo 24 March 2007 (has links)
As a license-exempt technology, Ultra Wideband (UWB) can be used for numerous commercial and military applications, including ranging, sensing, low-range networking and multimedia consumer products. In the networking and consumer fields, the technology is envisioned to reach the mass market, with a very high density of UWB devices per home and office. The technology is based on the concept of transmitting a signal with very low power spectral density (PSD), while occupying a very wide bandwidth. In principle, the low emissions mask protects incumbent systems operating in the same spectrum from being interfered with, while the wide bandwidth offers the possibility of high data rates, in excess of 250 Mbps.
UWB has been regulated to operate in the 3.1 to 10.6 GHz portion of the spectrum, with an emissions mask for the lower and upper bands outside this range. The commercial wireless mobile services based on third generation (3G) networks occupy a portion of the spectrum in the 2 GHz band, falling under the UWB emissions mask.
UWB and UMTS (Universal Mobile Telephone Systems) devices will coexist, sharing the same spectrum.
In this research, we investigate the UWB-3G coexistence problem, analyzing the impact of UWB on UMTS networks. Firstly, we review the mathematical model of the UWB signal, its temporal and spectral properties. We then analyze and model the effects of the UWB signal on a narrowband receiver. Next, we characterize the response of the UMTS receiver to UWB interference, determining its statistical behavior, and establishing a model to replicate it. We continue by proposing a link level model that offers a first order quantitative estimate of the impact of a UWB interferer on a UMTS victim receiver, demonstrating the potentially harmful effect of UWB on the UMTS link. We elaborate on that initial evidence by proposing and implementing a practical systemlevel algorithm to realistically simulate the behavior of the UMTS network in the presence of multiple sources of UWB interference.
We complete the research by performing UMTS system level simulations under various conditions of UWB interference, with the purpose of assessing its impact upon a typical UMTS network. We analyze the sensitivity of the main UWB parameters affecting UMTS performance, investigating the coverage and capacity performance aspects of the network. The proposed analysis methodology creates a framework to characterize the impact that mass-deployed UWB can have on the performance of a 3G system.
The literature on UWB-3G coexistence is inconclusive, and even contradictory, as to the impact UWB can have on the performance of third-generation wireless networks. While some studies show that UWB can be highly detrimental to 3G networks, others have concluded that both systems can gracefully coexist. Through this study, we found that at the current emissions limits regulated for UWB, a mass uptake of this technology can negatively affect the performance of third-generation (3G) wireless networks. The quality of service experienced by a 3G user in close proximity to an active UWB device can be noticeably degraded, in the form of reduced coverage range, poor voice quality (for a voice call), lower data rates (for a data session) or, in a extreme situation, complete service blockage. As the ratio of UWB devices surrounding a 3G user grows, the degradation becomes increasingly more evident. We determined that in order for UWB tocoexist with 3G networks without causing any performance degradation, a minimum power backoff of 20 dB should be applied to the current emission limits. / Ph. D.
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A Location-aided Decision Algorithm for Handoff Across Heterogeneous Wireless Overlay NetworksSaleh, Areej 04 August 2004 (has links)
Internetworking third generation (3G) technologies with wireless LAN (WLAN) technologies such as Universal Mobile Telecommunication Systems (UMTS) and IEEE 802.11, respectively, is an emerging trend in the wireless domain. Its development was aimed at increasing the UMTS network's capacity and optimizing performance. The increase in the number of wireless users requires an increase in the number of smaller WLAN cells in order to maintain an acceptable level of QoS. Deploying smaller cells in areas of higher mobility (e.g., campuses, subway stations, city blocks, malls, etc.) results in the user only spending a short period of time in each cell, which significantly increases the rate of handoff. If the user does not spend sufficient time in the discovered WLAN's coverage area, the application cannot benefit from the higher data rates. Therefore, the data interruption and performance degradation associated with the handoff cannot be compensated for. This counters the initial objective for integrating heterogeneous technologies, thus only handoffs that are followed by a sufficient visit to the discovered WLAN should be triggered. The conventional RF-based handoff decision method does not have the necessary means for making an accurate decision in the type of environments described above. Therefore, a location-aided handoff decision algorithm was developed to prevent the triggering of handoffs that result from short visits to discovered WLAN's coverage area. The algorithm includes a location-based evaluation that runs on the network side and utilizes a user's location, speed, and direction as well as handoff-delay values to compute the minimum required visit duration and the user's trajectory. A WLAN coverage database is queried to determine whether the trajectory's end point falls within the boundaries of the discovered WLAN's coverage area. If so, the mobile node is notified by the UMTS network to trigger the handoff. Otherwise, the location-based evaluation reiterates until the estimated trajectory falls within the boundaries of the discovered WLAN's coverage area, or the user exits the coverage area. By taking into consideration more then merely RF-measurements, the proposed algorithm is able to predict whether the user's visit to the WLAN will exceed the minimum requirements and make the decision accordingly. This allows the algorithm to prevent the performance degradation and cost associated with unbeneficial/unnecessary handoffs. / Master of Science
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Method and Apparatus for Supporting Ad-Hoc Networking over UMTS (Universal Mobile Telecommunications System) Protocol.Barnawi, A., Gardiner, John G. January 2007 (has links)
No / A method and apparatus are provided for ad hoc networking over a universal mobile telecommunications system (UMTS) . In the method, if user equipment (40A) (such as a mobile phone) is not within normal cell coverage (20) , then in an uplink procedure a message which would normally have not be able to be transmitted directly from the User Equipment (40A) to a Base Station (10) is instead forwarded towards the Base Station (10) via one or more intermediate User Equipments (40B) . In the method, the user equipment (40A) is arranged to synchronise itself with the Base Station (10) to acquire timeslot and frame synchronisations and thence perform probing activities to build up a list of neighbouring User Equipments. From this list and power and signal to interference calculations the user equipment (40A) is able to work out the relative positions of its neighbours with respect to the Base Station and itself and come to a routing decision for forwarding its message towards the Base Station.
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Analyse, implémentation et évaluation de performance de la future méthode d'accès HSDPAHadjar, Omar Rachid 12 April 2018 (has links)
La technologie HSDPA (High Speed Downlink Packet Access) représente la première étape d’évolution de la méthode d’accès du réseau mobile de troisième génération UMTS (Universal Mobile Telecommmunications Service). Cette technologie permet d’obtenir des débits théoriques supérieurs à 10 Mbps sur le lien descendant et de supporter des services à valeur ajoutée, tels que l’accès Internet à haute vitesse, le téléchargement de fichiers audio et vidéo, la réception de programmes télévisés et la visiophonie. Ces améliorations sont rendues possibles grâce à une combinaison de propriétés qui sont à la base du HSDPA et qui consistent à adapter le codage et la modulation en fonction des conditions du canal radio (AMC : Adaptative Modulation and Coding), à effectuer des retransmissions rapides de paquets erronés (HARQ : Hybrid Automatic Repeat ReQuest) et à utiliser des méthodes d’ordonnancement intelligentes plus rapides. Même si l’introduction de ces nouvelles techniques contribue à une augmentation de la capacité du système, elle engendre toutefois une plus grande complexité dans l’évaluation de ses performances dans des conditions réelles. Dans ce contexte, nous proposons une implémentation et une évaluation de la méthode d’accès HSDPA qui prend en considération les spécifications techniques des Node B et des terminaux mobiles d’un système UMTS. Les résultats obtenus de cette implémentation, basés sur plusieurs scénarios utilisant des données géographiques réelles, montrent que le système réussit à satisfaire aux exigences des services multimédia. / High speed downlink packet access (HSDPA) is an add-on technology for W-CDMA that allows higher downlink data rates and greater base station capacity. With HSDPA, W-CDMA systems, which today are seemingly stuck at 384 kbps, will be able to shift gears and move ahead to so-called 3.5G performance with over 10 Mbps throughput on the downlink. The incorporation of HSDPA in Release 5 of the 3GPP W-CDMA specification is the most significant change on the RF side since Release 99. Advanced techniques such as adaptive modulation and coding (AMC) and hybrid automatic repeat request (HARQ) are used to modify the coding and physical layer parameters adaptively in response to the instantaneous channel quality, thus enabling gains in spectral efficiency and data rates. On the other hand, such improvements also bring a higher complexity degree in the evaluation of the radio subsystem performance. This evaluation is crucial for operators who are willing to provide value-added services with rich multimedia contents. This thesis aims at implementing and simulating a radio access network on a real geographic area using the HSDPA features. Results show that such features enable to satisfy the quality of service requirements needed to support the new data-oriented services.
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[en] PLANNING OF UMTS NETWORKS AND INTEROPERABILITY ASPECTS WITH GSM/GPRS/EDGE NETWORKS / [pt] PLANEJAMENTO DE REDES UMTS E ASPECTOS DE INTEROPERABILIDADE COM REDES GSM/GPRS/EDGEROBERTO BATISTA VEREZA DE OLIVEIRA 27 November 2007 (has links)
[pt] O presente trabalho tem como meta analisar os aspectos de
planejamento de
redes celulares UMTS coexistentes com redes GSM,
abordando
de forma
sintetizada os principais pontos de interesse para as
operadoras de telefonia celular
móvel que eventualmente estejam considerando a
possibilidade de coexistência
entre esses sistemas. São abordados de forma especial os
processos de
interoperabilidade entre as redes UMTS e GSM/GPRS/EDGE. / [en] This work has as its purpose to analyze and present on a
concise manner the
planning aspects for new UMTS networks as well as its
interoperability issues
concerning GSM legacy layer, serving as reference for the
wireless network
providers which adopt UMTS over GSM/GPRS/EDGE as their
short-term option
for deploying existing networks. It will be given special
attention to most of
interoperability issues which are defined by the
standardization bodies (mainly
INTER-RAT) and others which are being offered by some of
the most
representative equipments providers.
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Duomenų perdavimo spartos tyrimas judriojo ryšio tinkluose / Data Transfer Throughput Research over Mobile NetworksŽvinys, Karolis 23 July 2012 (has links)
Baigiamajame magistro darbe nagrinėjami su duomenų perdavimo sparta susiję ryšio kanalo parametrai. Pirmojoje darbo dalyje apžvelgiami užsienio ir Lietuvos mokslininkų atliekami tyrimai kanalo parametrų, susietų su duomenų perdavimo sparta, tematika, analizuojama mobilaus tinklo kanalo parametrų matavimams skirta iranga. Kituose darbo skyriuose išskiriami konkretūs su duomenų pralaidumu sąveikaujantys parametrai. Naudojant šiuos parametrus darbe kuriami modeliai, skirti duomenų perdavimo spartai prognozuoti tikrinamas modelių tinkamumas bei tikslumas. Tiesinės prognozės atveju pasiektas 77,83%, o netiesinės prognozės atveju – 76,19% tikėtinos duomenų perdavimo spartos prognozės tikslumas. Atsižvelgiant į vartotojų interesus siūlomi jų įrangai pritaikyti prognozės modeliai. Darbo pabaigoje tikrinamas sukurtų modelių adekvatumas realiomis ryšio salygomis. / This work analyzes communication channel settings of UMTS technology which are related with a data transfer throughput. Further course of study includes the most specific parameters selection, that arethe most crucial for data speed. Using these parameters it is developed the models suitable for data transfer throughput prediction. To build the model the linear and nonlinear forecasting methods are applied. The linear prediction is made by using linear regression, nonlinear – neural networks. Using linear prediction model 77.83% forecast accuracy has been achieved, while the nonlinear forecast expected transmission rate forecast accuracy is 76.19%.These prediction models accuracy obtained by using eight parameters of the communication channel. Finally in this paper are built the data throughput prediction models that allow to predict data speed using only standard terminal presented channel parameters. At the end all built prediction models are checked in real communication environment.
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