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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Benchmarking of mobile network simulator, with real network data

Näslund, Lars January 2007 (has links)
<p>In the radio network simulator used in this thesis the radio network from a specific operator is modeled. The real network model in the simulator uses, a 3-D building database, realistic site data (antenna types, feederloss, ...) and parameter setting from field. In addition traffic statistics are collected from the customer’s network for the modeled area. The traffic payload is used as input to the simulator and creates an inhomogeneous traffic distribution over the area. One of the outputs from the simulator is power per cell.</p><p>The purposes of this thesis are to identify simulation accuracy compared to reality and to evaluate and improve the simulation models and the methods used when making a simulation of a real WCDMA network with the Astrid simulator.</p><p>In cellular systems the transmitted power influences the interference in the network and the interference is in turn affecting the performance. As the transmitted RBS power influences the downlink interference, it is important that the RBS power level is accurate in the simulator. Therefore the simulated RBS power is benchmarked with the real RBS power. The traffic payload from the real network is used as input into the simulator. Based on the traffic payload the simulator generates RBS power as output. The simulated RBS power is then compared with the measured RBS power.</p><p>It has been found that the standard parameter setting in the simulator gives in average about 1 W too much RBS power used in the simulations compared to reality. After investigation it was detected that two reasons for the overestimated power are that the common control channels (CCCH) power setting and the feederloss is not set to the same values as in field. With the new CCCH settings and feederloss the simulator overestimates the RBS power with 0.5 W in average. As the traffic today is relatively low the parameters that only affect the dedicated channels can only be used to make small adjustments of the simulated RBS power.</p>
2

A study on co-opetition between 3G and WiMAX

Chen, Shao-Wen 21 January 2008 (has links)
3G and WiMAX are two main streams in the existent broadband wireless access technologies. It has been 6 years since the 3G license be released in October, 2001. 3G enters the market much earlier; it not only extends the mobility of 2G, but combines the advantage of sounds, data, and image. But so far, it still can¡¦t inspire customer¡¦s demand. On the other hand, with the power of Intel, the new technology, WiMAX intends to adopt the successful experience of WiFi into the market of broadband wireless access technologies. WiMax can also offer triple-play, even lower cost, and faster transfer. When these two similar technologies both exist in the market, will they be complementary or mutually exclusive? This question will be discussed in the paper. The conclusion is, after comparing 3G with WiMAX, figuring out 6 key factors that would affect the co-competition. 1.the time of technology competition 2. segmentation of services 3. demand of customers 4.market orientation and strategy 5. policy of government 6. building ecological system. Basically speaking, when WiMAX moves toward 3G, the market share is depended on technology maturity, entrance time, using habit of customers, and cost advantage of product.
3

Benchmarking of mobile network simulator, with real network data

Näslund, Lars January 2007 (has links)
In the radio network simulator used in this thesis the radio network from a specific operator is modeled. The real network model in the simulator uses, a 3-D building database, realistic site data (antenna types, feederloss, ...) and parameter setting from field. In addition traffic statistics are collected from the customer’s network for the modeled area. The traffic payload is used as input to the simulator and creates an inhomogeneous traffic distribution over the area. One of the outputs from the simulator is power per cell. The purposes of this thesis are to identify simulation accuracy compared to reality and to evaluate and improve the simulation models and the methods used when making a simulation of a real WCDMA network with the Astrid simulator. In cellular systems the transmitted power influences the interference in the network and the interference is in turn affecting the performance. As the transmitted RBS power influences the downlink interference, it is important that the RBS power level is accurate in the simulator. Therefore the simulated RBS power is benchmarked with the real RBS power. The traffic payload from the real network is used as input into the simulator. Based on the traffic payload the simulator generates RBS power as output. The simulated RBS power is then compared with the measured RBS power. It has been found that the standard parameter setting in the simulator gives in average about 1 W too much RBS power used in the simulations compared to reality. After investigation it was detected that two reasons for the overestimated power are that the common control channels (CCCH) power setting and the feederloss is not set to the same values as in field. With the new CCCH settings and feederloss the simulator overestimates the RBS power with 0.5 W in average. As the traffic today is relatively low the parameters that only affect the dedicated channels can only be used to make small adjustments of the simulated RBS power.
4

Podpora služeb reálného času v současných mobilních sítích třetí generace / Support of real-time services in recent 3G mobile networks

Vinkler, 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.
5

第三代行動通信業務執照競價釋出機制之研究

余亭美 Unknown Date (has links)
隨著電信科技的進步以及經濟自由化的風潮,電信自由化已成為世界潮流。我國電信自由化之推動起源於加入世界貿易組織之政策推動,以及落實入會諮商中與美國雙邊貿易協議所作出之有關電信之承諾,採取漸進式、階段性的開放政策,於民國84年起陸續開放行動通信、衛星通信及固定通信等多項電信業務。 我國在電信開放自由化後,電信市場已逐步由獨占經營轉變為自由競爭,其中行動通信以極快的速度成長,這是自由化以及有效管制二個不可分割的因素所形成,顯示開放市場參進、促進市場競爭機制之成效。隨著無線通訊技術不斷地精進,無線通訊、語音通訊、數據通訊及網際網路的緊密結合,行動寬頻通信時代已經來臨,為加速推動行動寬頻網路建設,讓消費者可以一機走遍天下,不論何時、何地皆能享受到高品質通訊服務,我國於2002年開放第三代行動通信業務,併以電子式競價作業方式釋出五張3G執照,總標金達488.99億元。 各國因經營環境不同,行動電話發展殊異,再加上頻率使用的情形不同,故設計出不同的發照方式。本論文採定性分析之方法,探討相關文獻並佐以實例探討,以管制理論與電信自由化等理論為基礎,從頻譜規劃、釋照架構的設計及相關配套管制措施的角度分析我國此次發放執照的機制,並藉由對各國釋出電信執照方式的優缺點綜合歸納,提出未來業務開放可供參考之意見,以達成電信資源之有效分配、應用與管制。 我國此次3G業務執照釋出方式係採用頻譜與業務執照合併釋出的方式,同時規定不得將頻率全部或部分租借、轉讓或抵押予他人。這種釋照方式雖可以保障行動通信業務執照取得人的經營權益,但業者對頻段僅有使用權,無法使頻譜有更靈活的運用與發展空間。倘若業者經營不善,所指配的頻段僅能繳回主管機關重新分配,不能進行移頻或轉讓,而業者並無先行繳回頻段的誘因,將導致頻段資源的閒置,形成稀有資源的浪費。我國發照制度應不再以「業務」作為執照發放管制之方式,而改以「資源有效利用」為執照發放之最高原則,建立頻率交易及回收的機制,允許業者對於頻率多元化的應用。
6

A study of Multinational Corporations' Development and Planning of Mobile Telecommunication industry in China

Cheng, Yu-chao 08 February 2007 (has links)
In the development of the global telecommunication industry, the telecommunications market in China is very important for development and planning of Multinational Corporations¡¦ (MNCs) global overall arrangement. Thus, the main purpose of this research is to discover the trend of international telecommunications industry, especially mobile communication industry. In addition, discuss the position and importance of China¡¦s telecommunications market within the global market under the framework of international telecommunication market. Moreover, we have to further analyze the policy and planning of the China government. Furthermore, We have to discuss the strategies and cooperated cases of telecom operators and equipment manufacturers in China¡¦s telecommunication market. Besides, Understanding the considerations of China government¡¦s criteria and principle of opening 3G in mainland China¡¦s telecommunication market is also an important issue. Finally, we have to realize what kind of role that foreign telecom firms act in the development of the China¡¦s telecommunications market.
7

The Research of Third Generation Mobile System Market Strategies

Tseng, Shun-Cheng 22 July 2002 (has links)
Abstract With the tremendous growing of mobile communication and internet market in the 90s decade, electronic commence (EC) and broadband multimedia also begin to demonstrate their market potential in next few years. We can almost be sure that a combination of these markets equals success. The 3G system, created to meet the requirements mentioned above, undoubtedly to be the star of future. Basically, the 3G system is an extension of the 2G system. There is no question that, to date, Japan has been the mobile Internet success story with its legendary i-mode service. But in much of the world, mobile internet market has generally not materialized quite as quick as anticipated, due to a number of factors. Mobile EC and multimedia markets are facing the same situation. It reveals that 3G market, unlike the explosively growing 2G market, will be full of uncertainty. This thesis focuses on the uncertain 3G market. Base on the theory of ¡§Strategy under Uncertainty¡¨ , we will provide some competition strategies for telecom operators. We also provide a risk¡Vanalysis model, with the theory of ¡¨ Discovery Driver Planning¡¨, for the operator to evaluate the high risk in such an uncertain market.
8

Mobile Wireless System Interworking with 3G and Packet Aggregation for Wireless LAN

Ransbottom, J. Scot 27 April 2004 (has links)
This research considered the efficient transmission of data within a wireless local area network (WLAN) system. A simulation model was developed to study the performance of our protocol, AGG-MAC (aggregated medium access control). AGG-MAC is a simple and elegant medium access control (MAC) protocol designed to improve performance by transmitting a maximal quantity of data with minimal overhead. Our enhancement to IEEE 802.11, AGG-MAC yields dramatic improvements in both local and global throughput. It furthermore reduces jitter in support of real time communications requirements such as voice over IP (VoIP). In support of heterogeneous roaming between Third Generation (3G) Wideband CDMA (WCDMA), specifically Universal Mobile Telecommunications System (UMTS) and WLAN systems, we constructed a simulation environment which allowed the evaluation of AGG-MAC in such a system. We further demonstrated the suitability of AGG-MAC throughout a range of infrastructure and ad hoc based WLAN scenarios. The AGG-MAC protocol enhancement provides significant performance improvements across a range of wireless applications, while interoperating with standard IEEE 802.11 stations. Performance is commensurate to original WLAN MAC performance for applications that do not benefit from packet level aggregation. The key contributions of this research were two-fold. First was the development of an OPNET simulation environment suitable for evaluation of future protocols supporting tightly coupled, heterogeneous WLAN and 3G systems. Secondly was the implementation and testing of the AGG-MAC protocol which aggregates suboptimal size packets together into a single frame, thereby amortizing the overhead. / Ph. D.
9

Radio Link Performance of Third Generation (3G) Technologies For Wireless Networks

Nader, Gustavo 15 July 2002 (has links)
Third generation wireless mobile communication networks are characterized by the increasing utilization of data services — e-mail, web browsing, video streaming, etc. Such services allow the transition of the network from circuit switched to packet switched operation (circuit switched operation will still be supported), resulting in increased overall network performance. These new data services require increased bandwidth and data throughput, due to their intrinsic nature. Examples are graphics-intensive web browsing and video streaming, the latter being delay sensitive and requiring priority over less sensitive services such as e-mail. This increasing demand for bandwidth and throughput has driven the work of third generation standardization committees, resulting in the specification of improved modulation and coding schemes, besides the introduction of more advanced link quality control mechanisms. Among the several proposals for the evolution from 2G to 3G, GPRS (General Packet Radio Services) and EDGE (Enhanced Data Rates for GSM Evolution) stand out as transitional solutions for existing TDMA IS-136 and GSM networks (they are also referred to as 2.5G systems). In the CDMA arena, WCDMA (Wideband CDMA) has emerged as the most widely adopted solution, with CDMA 2000, an evolution from IS-95, also being considered. This thesis compiles and analyzes the results of the work by the standardization committees involved in the specification of 3G standards, focusing on the receiver performance in the presence of additive noise, fading and interference. Such performance results will ultimately determine design and optimization conditions for 3G networks. This document concerns the description of the TDMA-based 2.5G solutions that allow the introduction of multimedia and enhanced data services to existing 2G networks. It focuses on GPRS and EDGE. It also addresses WCDMA — a 3G spread spectrum solution. Such proposals permit the utilization of existing spectrum with increased efficiency, yielding extended network capacity and laying the ground for full support of wireless multimedia applications. The study is focused on the link implementation aspect of these solutions, showing the impact of the modulation schemes and link quality control mechanisms on the performance of the radio link. / Master of Science
10

台灣3G行動加值服務發展之研究-日韓發展之啟示 / Research on the Development of 3G Mobile Value-Added Services in Taiwan - Implications from Japan & Korea Markets

廖淑英, Liao,Shu-Ying Unknown Date (has links)
3G行動電話的優勢在於傳輸速度,可達384Kbps以上,因此,在政府開放五張執照後,各家業者皆投入巨額資金經營,期藉由傳輸速度快的優勢,可以發展出更多的行動加值服務內容,以期在語音營收成長飽和之下,創造另一營收來源。然而,觀察3G行動加值服務發展現況,發現台灣3G行動加值營收比GPRS時代,成長不大,用戶使用意願也不高。因此,本研究期望,透過了解全世界發展3G行動加值服務最成功的日本與韓國兩個市場,其3G發展過程中曾碰到過的問題,及其後的改善方案,提供給國內政府/業者參考,以便能縮短學習曲線,發展出殺手級的加值服務,提高營收,帶動3G產業的發展。 本研究經由文獻與理論探討、電信產業發展概況、日本行動加值服務市場分析、韓國行動加值服務市場分析與台灣行動加值服務市場分析後,最後作成結論與建議,並提出後續研究課題的建議。 經研究與分析日本和韓國市場,了解日本與韓國3G行動加值服務發展過程中,所碰到過的困境及其後續改善之方案,並對政府與電信營運商提出以下的結論與建議: 結論 : 一、 從以下日韓3G初期發展失敗的經驗,可為台灣業者借鏡以避免重蹈覆轍: 1、基地台設置不足,導致通訊品質不佳,用戶沒信心 2、加值服務內容定價過高及計價方式複雜 3、3G手機價格高 4、服務內容不具吸引力 二、 日韓 3G成功關鍵因素可提供台灣電信業者參考與學習 1、提高網路普及率 2、提供創新服務內容 3、操作簡便的服務 4、簡單易懂收費模式 5、人性化的3G 服務品牌 三、 網路品質改善第一優先,以建立用戶使用信心與意願 四、 藉由了解日韓3G發展過程,可以縮短台灣業者學習與摸索的時間 建議 : 壹、 政府方面: 一、基地台網路: 協調業者以共構的方式及加速整合UMA技術以解決網路品質的問題。 二、技術平台與內容產業: 制定適當的產業政策,以協助整合產業上中下游業者,以帶動產業 研究與發展。 貳、 電信營運商方面: 一、客戶數及終端設備: 電信產業再次併購與整合,以便擴大客戶數及求得最大經濟邊際效益。 二、內容與服務平台: 積極扮演內容服務開發與技術平台整合角色,以帶動內容產業的蓬 勃發展,並創造「皆贏」的局面。 三、費率: 提供高、中、低「吃到飽」簡單易懂費率,滿足不同需求的用戶。 / The advantage of 3G is on the speed up to 384 Kbps. After Taiwan government released five licenses of 3G to operators in 2002, the 3G operators started to invest lots of capital in building the infrastructure & operating. They all expected to develop more value-added services to enlarge data revenue of 3G by its advantage of high speed. However, data revenue of 3G is not obviously enlarged after it was launched since 2005. This research focused on studying the experience of Japan and Korea in 3G market as they are the most successful area in the development of 3G and also hope to learn from them by their successful experience and the difficulties they had met and overcome in the past. By learning from them, Taiwan operators could shorten the learning curve of the development of 3G and accelerate the development of value-added services and find out the killer applications to enlarge data revenue of 3G. This research conferred with literature & theory、the development of Telecom industry、the analysis of mobile value-added services in Japan、the analysis of mobile value-added services in Korea and the development of mobile value-added services in Taiwan. In the end, it came out to the points of conclusion and suggestion to this research. After analyzing 3G market in Japan and Korea, this research pointed out below conclusions and suggestions to Taiwan government and operators. Conclusions : 1. The operators can learn by the failure factors of Japan & Korea to avoid it happens again in Taiwan market as below listed: A. The establishment of infrastructure was not enough to provide good quality in connection. B. The pricing of value-added services is too high and too complicated to users. C. The pricing of 3G handset is too high. D. The content of value-added services is not attractive to users. 2. The operators can learn by the key success factors of Japan & Korea in 3G to accelerate blooming 3G market in Taiwan as below Listed: A. High infrastructure networking penetration could improve the quality of connection. B. To create innovative value-added services to attract users. C. To provide user-friendly handset. D. To design simple and various flat rate. E. To promote 3G services brand instead of 3G technology. 3. The first priority is to improve the networking quality to enhance the faith of consumer to use 3G services. Suggestions : 1. To Taiwan government : A. In infrastructure networking side: Taiwan Government shall coordinate operators to co-build infrastructure networking and accelerate the integration of UMA (Unlicensed Mobile Access) to improve the quality of networking. B. In technology platform and content side: Taiwan Government shall set up appropriate industry policy to encourage、integrate and drive industry to go forward. 2. To Taiwan operators: A. In customer base side: By merging each other to enlarge the customer base to reach max. economic benefits in tailor-made handset and overhead. B. In content and service platform: Operators shall aggressively play the role to integrate content service development and technology platform to drive content industry to go forward and create the win –win. C. In air rate: To provide various and simple flat rate to meet various customers need. Key Words: 3G、3G Mobile Phone、Value-Added Service、Japan 3G、Korea 3G

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