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Analise do desempenho do sistema 3G 1xEV-DV no enlace direto / 1xEV-DV 3G systems forward link performance analysisBassi, Tania Aida Garcia 21 February 2006 (has links)
Orientador: Shusaburo Motoyama / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-06T08:13:44Z (GMT). No. of bitstreams: 1
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Previous issue date: 2006 / Resumo: Neste estudo, o desempenho do enlace direto do sistema I xEV -DV é analisado através de simulações e o tempo médio de atraso dos pacotes. a vazão de dados e a utilização de enlace são avaliados em função do carregamento de tráfego do sistema. Para a realização das simulações foi desenvolvido. na ferramenta de software /v/atlab, um modelo que representa o processamento e escalonamento da estação rádIo base do sistema IxEV-DV. antes da transmissão na interface aérea. bem como os modelos baseados em tráfego real de dados WAP, HTTP e FTP. O enlace direto do sistema I xEV -DV é analisado em cenários que consideram o escalonamento FIFO e o escalonamento baseado em prioridade de taxas, mostrando a redução do tempo médio de atraso dos pacotes no sistema com prioridade. Além disto. é possível verificar e quantificar a eficiência da 1111plementação da multiplexação por divisão em código (COM) além da multiplexação por divisão no tempo (TOM) no enlace direto. Os resultados do sistema 1 xEV -DV com tráfego W AP, HTTP e FTP são também comparados aos resultados obtidos com tráfego poissoniano, mostrando as diferenças e a importância da utilização de modelos de tráfego de dados reais / Abstract: In this study, the forward link performance 01' the I xEV -DV system is analyzed through simulations. and the average packet delay, the data throughput and the link utilization are evaluated in function of the system traffic load. For the simulations, it was developed in Matlab software tool, a model that represents the I xEV -DV radio base station processing and scheduling, before the aerial interfaee transmission. and the mode1s based in real data traffic WAP, HTTP and FTP. The forward link 01' the I xEV -DV system is analyzed in scenarios that consider FIFO scheduling and data rate priority scheduling, showing the average packet delay reduction in the system with priority. Besides, it is possible to verify and quantify the efficiency of the code division multiplexing (CDM) implementation besides the time division muItiplexing (TDM) in the forward link. The results of IxEV-OV system with WAP, HTTP and FTP traffic are also compared with the results obtained with Poisson traffic, showing the differences and the importance of the real data traffic models utilization / Mestrado / Telecomunicações e Telemática / Mestre em Engenharia Elétrica
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4G LTE : eMBMS with MBSFN Service Simulation using OPNETWalid, Abdelrahman January 2014 (has links)
Long Term Evolution (LTE) known in the market as 4G LTE, it is an evolution of the GSM/UMTS standard. The overall aim of LTE was to provide a new radio access technology focusing on packet-switched data only. LTE has provided a new peak download rates, low data transfer latencies, and improved the support for mobility. 3Th Generation Partnership Project (3GPP) specialized that LTE released 10 and beyond known as LTE-advanced it is the second evolution of LTE. It has some services such as Coordinated Multipoint Transmission and Reception (CoMP), evolved Multimedia Broadcast and Multicast Service (eMBMS) with Multicast-Broadcast Single-Frequency Network (MBSFN). The development still continuous on LTE-advanced, it is intended to meet the requirement of advanced application that will become common in the wireless marketplace in future. The goals of this project is to simulate one of LTE-A services on LTE standard such as CoMP or/and eMBMS with MBSFN using OPENT LTE, and measure some statistic such as spectral efficiency and also some other statistics, describe centralization vs. decentralization in LTE, and synchronization in the base station in LTE. OPNET LTE support eMBMS with MBSFN, and don’t support CoMP, the simulation has been done by using eMBMS with MBSFN. Finally the objectives of the project has achieved, the result show that when eMBMS with MBSFN is implemented the throughput increased in the downlink to about 5.52 Mbps and in the uplink to about 5.18 Mbps, and also the system spectral efficiency increased in eNB1 from about 10.25 (bits/s/Hz/cell) to about 13.75 (bits/s/Hz/cell) and in eNB2 from about 10.25 (bits/s/Hz/cell) to about 17.25 (bits/s/Hz/cell). The project also answers if it is possible to have centralization in LTE, describe synchronization in the base station in LTE, and if OPNET is useful for big research.
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Viterbi Decoded Linear Block Codes for Narrowband and Wideband Wireless Communication Over Mobile Fading ChannelsStaphorst, Leonard 08 August 2005 (has links)
Since the frantic race towards the Shannon bound [1] commenced in the early 1950’s, linear block codes have become integral components of most digital communication systems. Both binary and non-binary linear block codes have proven themselves as formidable adversaries against the impediments presented by wireless communication channels. However, prior to the landmark 1974 paper [2] by Bahl et al. on the optimal Maximum a-Posteriori Probability (MAP) trellis decoding of linear block codes, practical linear block code decoding schemes were not only based on suboptimal hard decision algorithms, but also code-specific in most instances. In 1978 Wolf expedited the work of Bahl et al. by demonstrating the applicability of a block-wise Viterbi Algorithm (VA) to Bahl-Cocke-Jelinek-Raviv (BCJR) trellis structures as a generic optimal soft decision Maximum-Likelihood (ML) trellis decoding solution for linear block codes [3]. This study, largely motivated by code implementers’ ongoing search for generic linear block code decoding algorithms, builds on the foundations established by Bahl, Wolf and other contributing researchers by thoroughly evaluating the VA decoding of popular binary and non-binary linear block codes on realistic narrowband and wideband digital communication platforms in lifelike mobile environments. Ideally, generic linear block code decoding algorithms must not only be modest in terms of computational complexity, but they must also be channel aware. Such universal algorithms will undoubtedly be integrated into most channel coding subsystems that adapt to changing mobile channel conditions, such as the adaptive channel coding schemes of current Enhanced Data Rates for GSM Evolution (EDGE), 3rd Generation (3G) and Beyond 3G (B3G) systems, as well as future 4th Generation (4G) systems. In this study classic BCJR linear block code trellis construction is annotated and applied to contemporary binary and non-binary linear block codes. Since BCJR trellis structures are inherently sizable and intricate, rudimentary trellis complexity calculation and reduction algorithms are also presented and demonstrated. The block-wise VA for BCJR trellis structures, initially introduced by Wolf in [3], is revisited and improved to incorporate Channel State Information (CSI) during its ML decoding efforts. In order to accurately appraise the Bit-Error-Rate (BER) performances of VA decoded linear block codes in authentic wireless communication environments, Additive White Gaussian Noise (AWGN), flat fading and multi-user multipath fading simulation platforms were constructed. Included in this task was the development of baseband complex flat and multipath fading channel simulator models, capable of reproducing the physical attributes of realistic mobile fading channels. Furthermore, a complex Quadrature Phase Shift Keying (QPSK) system were employed as the narrowband communication link of choice for the AWGN and flat fading channel performance evaluation platforms. The versatile B3G multi-user multipath fading simulation platform, however, was constructed using a wideband RAKE receiver-based complex Direct Sequence Spread Spectrum Multiple Access (DS/SSMA) communication system that supports unfiltered and filtered Complex Spreading Sequences (CSS). This wideband platform is not only capable of analysing the influence of frequency selective fading on the BER performances of VA decoded linear block codes, but also the influence of the Multi-User Interference (MUI) created by other users active in the Code Division Multiple Access (CDMA) system. CSS families considered during this study include Zadoff-Chu (ZC) [4, 5], Quadriphase (QPH) [6], Double Sideband (DSB) Constant Envelope Linearly Interpolated Root-of- Unity (CE-LI-RU) filtered Generalised Chirp-like (GCL) [4, 7-9] and Analytical Bandlimited Complex (ABC) [7, 10] sequences. Numerous simulated BER performance curves, obtained using the AWGN, flat fading and multi-user multipath fading channel performance evaluation platforms, are presented in this study for various important binary and non-binary linear block code classes, all decoded using the VA. Binary linear block codes examined include Hamming and Bose-Chaudhuri-Hocquenghem (BCH) codes, whereas popular burst error correcting non-binary Reed-Solomon (RS) codes receive special attention. Furthermore, a simple cyclic binary linear block code is used to validate the viability of employing the reduced trellis structures produced by the proposed trellis complexity reduction algorithm. The simulated BER performance results shed light on the error correction capabilities of these VA decoded linear block codes when influenced by detrimental channel effects, including AWGN, Doppler spreading, diminished Line-of-Sight (LOS) signal strength, multipath propagation and MUI. It also investigates the impact of other pertinent communication system configuration alternatives, including channel interleaving, code puncturing, the quality of the CSI available during VA decoding, RAKE diversity combining approaches and CSS correlation characteristics. From these simulated results it can not only be gathered that the VA is an effective generic optimal soft input ML decoder for both binary and non-binary linear block codes, but also that the inclusion of CSI during VA metric calculations can fortify the BER performances of such codes beyond that attainable by classic ML decoding algorithms. / Dissertation (MEng(Electronic))--University of Pretoria, 2006. / Electrical, Electronic and Computer Engineering / unrestricted
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無線多媒體傳輸技術發展對無線影音產業價值鏈的影響以歐特斯科技公司為例葛葆華, Edward Ko Unknown Date (has links)
無線寬頻網路(Mobile Internet Broadband Network)的出現對於無線通訊產業、傳播媒體產業與影音內容產業產生了相當程度的影響,而數位化的科技發展更帶來通訊、傳播及平面媒體產業融合的可能性,無線寬頻影音串流(Mobile Internet Video Streaming)是一架構在此無線通訊媒體匯流後的新產物,透過觀察和分析它的演進發展,可以說明和解釋網路新媒體匯流造成傳統影音產業價值鏈的改變。
吾人將以無線通訊之影音播放技術之演進與發展,以及相對最先發生變化之影音產業經營環境,產生之影響,做產業價值鏈分析研究,進而了解產業經營環境之改變,新的價值創造流程及技術平台的關聯性。並藉由日本NTT DOCOMO之經驗,及對其供應商之觀察,了解台灣產業發展之可能趨勢,及策略建議藍圖。
本研究採P.W. Bane、S.P. Bradley & D.J. Collis (1998)三人提出之寬頻產業五層模式作為分析工具。五層模式分為內容(content)、包裝(package)、傳輸網路(transmission)、操作(manipulation) 及終端設備(terminal)五層架構。主要目的為以整體網路頻寬及技術演進的觀點進行分析五層間價值消長之關係,及整體網路之價值之改變。
我們發現在新的技術導入既有影音市場,由於網路之雙向特性,會產生網路效應及網路外部性,這些地方將產生新的價值所在,而擁有網路外部性的影音操作平台可獲得較高的價值。完整而消費者導向的影音操作平台,將首先累積產業之價值所在,影音操作平台的擁有者將成為產業的領導者,最終將成為標準的制定者。
影音內容的價值獲得來自網路外部性是經由更多人與內容來源(內容提供者)互動,造成下一次消費或其他使用者的外部性以及生產外部性,這樣的外部性是由虛擬連結產生.價值聚集於內容包裝層。
無線寬頻影音操作平台是服務成功的關鍵,有效的整合價值鏈及應用是必須在產業發展前完成,而完整的影音操作平台包含:內容製作壓縮平台、串流平台、訊息平台、及手機之用戶播放平台。
我們發現,新的技術導入市場,需要事先將價值鏈重新定義,整合出可行之新的商業模式,再依據新的價值鏈,新的服務流程去整合新的操作平台,投入服務後,由於是消費者導向的服務設計,可以降低消費者對新科技及新服務的學習門檻及進入障礙,而獲得市場認同。 / “Unlimited boundary & Ubiquitous content”
Because of the improving the bandwidth & compression technology of mobile Internet, there are a very extremely industrial convergency in communication, broadcasting, & video audio content industry. There are several new technology including streaming, MPEG, multi media message, 3G which push the whole world going to a new Ubiquitous environment & totally change the old value chain of video audio industry, but we still have no ideal where it should go & what will happen next.
We will try to research the technical evolution of video broadcasting which really influence our movie, TV industry. It will change the customer behavior of watching TV, or going to the movie. We especially want to find out where is the new value in the mobile Internet multi media industry.
We will use the 5 liars analysis model of broadband industry (P.W. Bane、S.P. Bradley & D.J. Collis (1998))as our basic methodology to find out how the three vertical industries became a new 5 horizontal industries, which are content, package, transmission, manipulation, & terminal. We also want to know how they work internally & externally.
We find that the video audio manipulation platform will become the key solution for this value chain, because of its network externality & network effect. The content providers also very important to provide the quality of contents to service the end customers.
How to consolidate a new valuable services process & user friendly interface is the big issue here for whom will invest a large of money to creat the new mobile internet portal & new audio vedio manipulation platform. They must think not only the user interface of handset, but also the mechanism of profit sharing between these different providers who never work together in the history.
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