Dissertations / Theses: 'Communication performance evaluation'

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Ncube, Ariage T. "Performance evaluation of a communication network." Master's thesis, University of Cape Town, 1995. http://hdl.handle.net/11427/21963.

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This work uses a simulation package to analyze the performance of a specific X.25 Value Added Communication Network (VAN), comprising a Network Administrator and a cluster of Network Concentrators (NCs). Detailed models of the network elements are developed, and system performance is analyzed in terms of network response time for the terminal users communicating across the network, identification of areas of bottlenecks in the NC system, and NC system throughput. The througput parameter is represented by the percentage of the output traffic to the load offered from the network of terminals. The performance of the Network Administrator system is also modeled, focusing particularly on the automatic restoration of service to failed NCs through downloading of operating software sets over the X.25 network. The final part consists of a model of a modification of the network manager components of the network as proposed in the DM upgrade project. In this section, NC loading time is again the desired performance indicator. It is shown that there is no noticeable improvement in this parameter between the original system and the proposed upgrade, both systems having a minimum loading time of about 3.5 to 6 minutes for a small network.

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Schütte, Miriam. "Communication, delegation and performance evaluation in organizations." Diss., Ludwig-Maximilians-Universität München, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-163574.

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Hamayun, Muhammad, and Nadeem Ahmed. "Performance Evaluation of Windows Communication Foundation’s Interoperability." Thesis, Blekinge Tekniska Högskola, Sektionen för datavetenskap och kommunikation, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-5294.

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Middleware eases the development of distributed applications. Expansion in the enterprise world entails integration of heterogeneous products, and there is a demand for a balance between performance, interoperability and security in the distributed applications. Windows Communication Foundation (WCF) offers a technology to build service-oriented, secure, reliable and interoperable distributed applications. The current literature contains few studies comparing the performance of WCF with other technologies, but it does not address the performance of WCF in a cross-technology communication. This master thesis experimentally evaluates the performance of WCF in unsecure and secure variants. It evaluates the performance in on-machine and cross-machine communication, and it addresses the performance of WCF’s interoperability with ASMX and Java. We have developed the service and client applications in both secure and unsecure variants. The experiments are then conducted using these applications in a laboratory setting. We have measured the performance in terms of throughput, response time, processor and memory utilization during the experiments. Our results show that in unsecure variants, the WCF service in cross-machine communication has the best response time than on-machine communication on small datasets. However, on large datasets the service in on-machine communication has the best response time. In secure variants, the service in on-machine communication has better response time than the cross-machine communication. In both secure and unsecure variants, the service has better throughput and consumed lesser resources in cross-machine communication than in on-machine communication. In case of WCF’s interoperability with ASMX and Java, both the secure as well as unsecure WCF service show more scalable performance for the WCF client than for ASMX and Java clients. The secure as well as unsecure service show better performance for the ASMX client than for the Java client. The unsecure variants of WCF service perform better than the secure variants, except in a few cases of memory utilization. Therefore, the performance of the WCF service degrades due to security.

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Lo, Chi-ming. "Analytical evaluation of wireless digital communication performance over fading channels." Hong Kong : University of Hong Kong, 2001. http://sunzi.lib.hku.hk/hkuto/record.jsp?B23295211.

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Ohtsuki, Kazuhiro. "STUDIES ON PERFORMANCE EVALUATION OF INTEGRATED COMMUNICATION SYSTEMS." Kyoto University, 1991. http://hdl.handle.net/2433/168738.

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本文データは平成22年度国立国会図書館の学位論文(博士)のデジタル化実施により作成された画像ファイルを基にpdf変換したものである
Kyoto University (京都大学)
0048
新制・論文博士
工学博士
乙第7572号
論工博第2483号
新制||工||845(附属図書館)
UT51-91-R431
(主査)教授長谷川利治, 教授茨木俊秀, 教授星野聰
学位規則第5条第2項該当

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盧志明 and Chi-ming Lo. "Analytical evaluation of wireless digital communication performance over fading channels." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2001. http://hub.hku.hk/bib/B3124208X.

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Santana, Regina Helena Carlucci. "Performance evaluation of LAN-based file servers." Thesis, University of Southampton, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.277643.

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賴文建 and Man-kin Lai. "Performance differences across communication environments in collaborative problem solving." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 1999. http://hub.hku.hk/bib/B31222791.

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Weingärtner, Elias David [Verfasser]. "Synchronized performance evaluation methodologies for communication systems / Elias David Weingärtner." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2013. http://d-nb.info/1047231425/34.

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Rashwand, Saeed. "Efficient Wireless Communication in Healthcare Systems; Design and Performance Evaluation." IEEE, 2010. http://hdl.handle.net/1993/9227.

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Increasing number of ageing population and people who need continuous health monitoring and rising the costs of health care have triggered the concept of the novel wireless technology-driven human body monitoring. Human body monitoring can be performed using a network of small and intelligent wireless medical sensors which may be attached to the body surface or implanted into the tissues. It enables carers to predict, diagnose, and react to adverse events earlier than ever. The concept of Wireless Body Area Network (WBAN) was introduced to fully exploit the benefits of wireless technologies in telemedicine and m-health. The main focus of this research is the design and performance evaluation of strategies and architectures that would allow seamless and efficient interconnection of patient’s body area network and the stationary (e.g., hospital room or ward) wireless networks. I first introduce the architecture of a healthcare system which bridges WBANs and Wireless Local Area Networks (WLANs). I adopt IEEE 802.15.6 standard for the patient’s body network because it is specifically designed for WBANs. Since IEEE 802.15.6 has strict Quality of Service (QoS) and priorities to transfer the medical data to the medical server a QoS-enabled WLAN for the next hop is needed to preserve the end-to-end QoS. IEEE 802.11e standard is selected for the WLAN in the hospital room or ward because it provides prioritization for the stations in the network. I investigate in detail the requirements posed by different healthcare parameters and to analyze the performance of various alternative interconnection strategies, using the rigorous mathematical apparatus of Queuing Theory and Probabilistic Analysis; these results are independently validated through discrete event simulation models. This thesis has three main parts; performance evaluation and MAC parameters settings of IEEE 802.11e Enhanced Distributed Channel Access (EDCA), performance evaluation and tuning the MAC parameters of IEEE 802.15.6, and designing a seamless and efficient interconnection strategy which bridges IEEE 802.11e EDCA and IEEE 802.15.6 standards for a healthcare system.

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Besbes, Habib (M Habib) Carleton University Dissertation Engineering Electrical. "Performance evaluation and statistical analysis of optical fiber communication systems." Ottawa, 1991.

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PAN, LINGLING. "PERFORMANCE EVALUATION, COMMUNICATION ENVIRONMENT, AND DECISION LEGITIMACY: A CASE IN CHINA." Diss., Temple University Libraries, 2012. http://cdm16002.contentdm.oclc.org/cdm/ref/collection/p245801coll10/id/168740.

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Mass Media and Communication
Ph.D.
Questions regarding the concept of legitimacy are central to social and political science. Exploring how people justify legitimacy and why people grant legitimacy to leadership and collective decisions in groups, organizations, and nations is generally agreed to be essential to scholarship on legitimacy. One line of research finds contributing factors in bureaucratic effectiveness and efficiency that can provide substantive benefits to people. Another line of research expands legitimacy to procedural elements such as fairness of treatment or quality of communication (deliberation) in the decision making process. This dissertation intends to contribute to the research of legitimacy and hopes to further the understanding of communication's role in decision outcome legitimacy by incorporating two sets of contributing factors: Performance factors and communication factors. This will enable a side-by-side comparison of instrumentalist and communicative factors in predicting legitimation. In addition, the study will observe the quality of the communication environment as a contextual variable upon which the relationship between performance elements and decision outcome legitimacy depends. Specifically, how the communication environment moderates the strength of the relationship between output of public service in a certain domain and the perceived legitimacy of the decision made in the same domain will be observed. Drawing on the framework from Habermas's theory of communicative action and the public sphere, the literature on deliberative democracy, and organizational studies, the project intends to observe how the communication environment or speech conditions (in Habermasian terms) may affect the legitimacy of a decision outcome, and at the same time may influence the relationship between the perceived performance in a certain public service sector and the perceived legitimacy of a decision outcome in the same sector. Using a sample of 255 adult residents in Chengdu, the capital city of Sichuan province in southwest China, the study found that perceived government performance and perceived speech conditions were both positively related to perceived legitimacy of government decision; furthermore, perceived speech conditions moderated the relationship between the performance evaluation and legitimacy perception. These findings suggest some important insights into the role of communication in political legitimation and the evolving communication expectations in China.
Temple University--Theses

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Chang, Jyun-Lyang. "Performance evaluation of wireless Networks on Chip." Pullman, Wash. : Washington State University, 2009. http://www.dissertations.wsu.edu/Thesis/Spring2009/j_chang_123009.pdf.

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Thesis (M.S. in electrical engineering)--Washington State University, May 2009.
Title from PDF title page (viewed on July 21, 2009). "School of Electrical Engineering and Computer Science." Includes bibliographical references (p. 42-43).

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Agrawal, Vivek. "Performance evaluation of Group Signature schemes in Vehicular Communication : A feasibility study for Vehicular Communication." Thesis, KTH, Kommunikationsnät, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-119816.

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The aim of this work is to show the effectiveness of techniques that allow a user to maintain its privacy and anonymity while participating in real word scenario. Users need to communicate with each other in many situations in order to share information. This creates the danger of the user’s privacy being breached and it can discourage users from taking active participation in any information sharing task. There are many real scenarios or application where users want to remain anonymous while having their communication secured. This is so in vehicular communication systems. Group signatures are versatile cryptographic tools that are suitable when we need security and privacy protection. A group signature scheme allows members of a group to sign messages on behalf of the group. Any receiver can verify the message validity but cannot discover the identity of the sender from the signed message or link two or more messages from the same signer. However, the identity of the signer can be discovered by an authority using a signed message. For this reason, Group Signature schemes were proposed in the context of vehicular communication systems. In this context, communication and computation overheads are critical. Thus, the focus of this thesis is to implement and compare different group signature schemes in terms of overhead introduced due to processing cost, and analytically evaluate their suitability for vehicular communication scenarios.

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Mohammed, Abbas Fadhel. "Performance evaluation of a direct sequence CDMA system." Thesis, University of Liverpool, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.385229.

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Hassanien, Mohamed A. M. "Error rate performance metrics for digital communications systems." Thesis, Swansea University, 2011. https://cronfa.swan.ac.uk/Record/cronfa42497.

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In this thesis, novel error rate performance metrics and transmission solutions are investigated for delay limited communication systems and for co-channel interference scenarios. The following four research problems in particular were considered. The first research problem is devoted to analysis of the higher order ergodic moments of error rates for digital communication systems with time- unlimited ergodic transmissions and the statistics of the conditional error rates of digital modulations over fading channels are considered. The probability density function and the higher order moments of the conditional error rates are obtained. Non-monotonic behavior of the moments of the conditional bit error rates versus some channel model parameters is observed for a Ricean distributed channel fading amplitude at the detector input. Properties and possible applications of the second central moments are proposed. The second research problem is the non-ergodic error rate analysis and signaling design for communication systems processing a single finite length received sequence. A framework to analyze the error rate properties of non-ergodic transmissions is established. The Bayesian credible intervals are used to estimate the instantaneous bit error rate. A novel degree of ergodicity measure is introduced using the credible interval estimates to quantify the level of ergodicity of the received sequence with respect to the instantaneous bit error rate and to describe the transition of the data detector from the non-ergodic to ergodic zone of operation. The developed non-ergodic analysis is used to define adaptive forward error correction control and adaptive power control policies that can guarantee, with a given probability, the worst case instantaneous bit error rate performance of the detector in its transition fi'om the non-ergodic to ergodic zone of operation. In the third research problem, novel retransmission schemes are developed for delay-limited retransmissions. The proposed scheme relies on a reliable reverse link for the error-free feedback message delivery. Unlike the conventional automatic repeat request schemes, the proposed scheme does not require the use of cyclic redundancy check bits for error detection. In the proposed scheme, random permutations are exploited to locate the bits for retransmission in the predefined window within the packet. The retransmitted bits are combined using the maximal-ratio combining. The complexity-performance trade-offs of the proposed scheme is investigated by mathematical analysis as well as computer simulations. The bit error rate of the proposed scheme is independent of the packet length while the throughput is dependent on the packet length. Three practical techniques suitable for implementation are proposed. The performance of the proposed retransmission scheme was compared to the block repetition code corresponding to a conventional ARQ retransmission strategy. It was shown that, for the same number of retransmissions, and the same packet length, the proposed scheme always outperforms such repetition coding, and, in some scenarios, the performance improvement is found to be significant. Most of our analysis has been done for the case of AWGN channel, however, the case of a slow Rayleigh block fading channel was also investigated. The proposed scheme appears to provide the throughput and the BER reduction gains only for the medium to large SNR values. Finally, the last research problem investigates the link error rate performance with a single co-channel interference. A novel metric to assess whether the standard Gaussian approximation of a single interferer underestimates or overestimates the link bit error rate is derived. This metric is a function of the interference channel fading statistics. However, it is otherwise independent of the statistics of the desired signal. The key step in derivation of the proposed metric is to construct the standard Gaussian approximation of the interference by a non-linear transformation. A closed form expression of the metric is obtained for a Nakagami distributed interference fading amplitude. Numerical results for the case of Nakagami and lognormal distributed interference fading amplitude confirm the validity of the proposed metric. The higher moments, interval estimators and non-linear transformations were investigated to evaluate the error rate performance for different wireless communication scenarios. The synchronization channel is also used jointly with the communication link to form a transmission diversity and subsequently, to improve the error rate performance.

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Abualhaol, Ibrahim Y. "Performance evaluation and optimizaton of cooperative communication systems over fading channels /." Full text available from ProQuest UM Digital Dissertations, 2008. http://0-proquest.umi.com.umiss.lib.olemiss.edu/pqdweb?index=0&did=1850446041&SrchMode=1&sid=2&Fmt=2&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1277479955&clientId=22256.

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Thesis (Ph.D.)--University of Mississippi, 2008.
Typescript. Vita. "July 2008." Dissertation director: Mustafa M. Matalgah Includes bibliographical references (leaves 161-165). Also available online via ProQuest to authorized users.

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Schumacher, K. "Performance evaluation and optimization of receivers for direct detection optical communication." Thesis, Bangor University, 1988. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380874.

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Sandström, Adam, and Nico Klerks. "Evaluation of 6TiSCH network performance for SDN-enabled IoT networks." Thesis, Mälardalens högskola, Akademin för innovation, design och teknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-48819.

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Within the Internet of Things (IoT) a need for new IP-compatible communication technologies has grown stronger during the last few years as the need to connect these IoT networks to the Internet has become increasingly more important. In this report, we evaluate IPv6 over the TSCH mode of IEEE 802.15.4e (6TiSCH) with the purpose of observing how different values for the enhanced beacon (EB) period affect certain network metrics such as delay, energy consumption, join time, and throughput. The EB period is a periodic message used in the Time Slotted Channel hopping (TSCH) protocol used to advertise the network. Our goal is to evaluate the effect of different EB periods on the network and determine if there would be a benefit of integrating SDN to change the EB period dynamically. To fulfill our goal, we will evaluate the effect of the change in EB period on the network metrics. This would be an indication that the 6TiSCH network benefits from an integration with SDN. The reason that we would draw this conclusion is because SDN would be capable of predicting the state of the network and from that update the EB period for the 6TiSCH network. Our results indicate that a lower EB period has a positive effect on join times in the network while a longer EB period has a positive effect on the end-to-end delay. Our results display a promising future for future research on the integration of SDN and 6TiSCH.

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Swedan, S. E. K. "Performance analysis of user access methods in the U.K. ISDN." Thesis, University of Strathclyde, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.381142.

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Munasinghe, Kumudu S., University of Western Sydney, of Science Technology and Environment College, and School of Computing and Information Technology. "VPN over a wireless infrastructure : evaluation and performance analysis." THESIS_CSTE_CIT_Munasinghe_K.xml, 2005. http://handle.uws.edu.au:8081/1959.7/662.

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This thesis presents the analysis and experimental results for an evaluation of the performance and Quality of Service (QoL) levels of a virtual private network( QoL) levels of a Virtual Private Network (VPN) implementation of an IEEE 802.11b wireless infrastructure. The VPN tunnelling protocol considered for the above study is IP security (IPSec). The main focus of the research is to identify the major performance limitations and their underlying causes for such VPN implementations under study. The experimentation and data collection involved in the study spans over a number of platforms to suit a range of practical VPN implementations over a wireless medium. The collected data includes vital QoS and performance measures such as the application throughput, packet loss, jitter, and round-trip delay. Once the baseline measure is established, a series of experiments are conducted to analyse the behaviour of a single IPSec VPN operating over an IEEE 802.11b infrastructure, after which the experimentation is extended by investigating the trends of the performance metrics of a simultaneously multiple VPN setup. The overall results and analysis of the investigation concludes that the CPU processing power, payload data size, packet generation rate and the geographical distance are critical factors affecting the performance of such VPN tunnel implementations. Furthermore, it is believed that these results may give vital clues for enhancing and achieving optimal performance and QoS levels for VPN applications over WLANs
Master of Science (Hons.)

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Takele, Berta. "Performance Evaluation of Simple Space-Time Block Coding on MIMO Communication System." Thesis, Växjö University, Växjö University, School of Mathematics and Systems Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:vxu:diva-6988.

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This thesis discuss on new technique called space time block coding (especially Alamouti's code) which is used to increase capacity and reliability of data transmission over time varying multi-path fading channel. The over all work of the thesis included in the following four chapters.

In chapter-1 we are going to cover some theoretical part which is useful to understand thesis work and in chapter-2 we will discuss the comparison between simple space time block code (Alamouti's code) and MRRC (Maximum Ratio Receiver Combining) which is receiver diversity and then in chapter-3 we will see the channel capacity & probability error performance for 2x2 Alamouti code over Rayleigh and Rice fading channel .Finally the conclusion and further work included in chapter-4.

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Mlonja, Chiku H. Chiku Hussein) Carleton University Dissertation Engineering Systems and Computer. "Performance evaluation of handover process in personal communication system using fuzzy algorithm." Ottawa, 1996.

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Ost, Alexander. "Performance of communication systems : a model based evaluation with matrix geometric methods /." Berlin ; Heidelberg [u.a.] : Springer, 2001. http://swbplus.bsz-bw.de/bsz090497023inh.htm.

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Concer, Nicola <1980&gt. "Design and Performance Evaluation of Network-on-Chip Communication Protocols and Architectures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2009. http://amsdottorato.unibo.it/1235/.

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The scale down of transistor technology allows microelectronics manufacturers such as Intel and IBM to build always more sophisticated systems on a single microchip. The classical interconnection solutions based on shared buses or direct connections between the modules of the chip are becoming obsolete as they struggle to sustain the increasing tight bandwidth and latency constraints that these systems demand. The most promising solution for the future chip interconnects are the Networks on Chip (NoC). NoCs are network composed by routers and channels used to inter- connect the different components installed on the single microchip. Examples of advanced processors based on NoC interconnects are the IBM Cell processor, composed by eight CPUs that is installed on the Sony Playstation III and the Intel Teraﬂops pro ject composed by 80 independent (simple) microprocessors. On chip integration is becoming popular not only in the Chip Multi Processor (CMP) research area but also in the wider and more heterogeneous world of Systems on Chip (SoC). SoC comprehend all the electronic devices that surround us such as cell-phones, smart-phones, house embedded systems, automotive systems, set-top boxes etc... SoC manufacturers such as ST Microelectronics , Samsung, Philips and also Universities such as Bologna University, M.I.T., Berkeley and more are all proposing proprietary frameworks based on NoC interconnects. These frameworks help engineers in the switch of design methodology and speed up the development of new NoC-based systems on chip. In this Thesis we propose an introduction of CMP and SoC interconnection networks. Then focusing on SoC systems we propose: • a detailed analysis based on simulation of the Spidergon NoC, a ST Microelectronics solution for SoC interconnects. The Spidergon NoC differs from many classical solutions inherited from the parallel computing world. Here we propose a detailed analysis of this NoC topology and routing algorithms. Furthermore we propose aEqualized a new routing algorithm designed to optimize the use of the resources of the network while also increasing its performance; • a methodology ﬂow based on modified publicly available tools that combined can be used to design, model and analyze any kind of System on Chip; • a detailed analysis of a ST Microelectronics-proprietary transport-level protocol that the author of this Thesis helped developing; • a simulation-based comprehensive comparison of different network interface designs proposed by the author and the researchers at AST lab, in order to integrate shared-memory and message-passing based components on a single System on Chip; • a powerful and flexible solution to address the time closure exception issue in the design of synchronous Networks on Chip. Our solution is based on relay stations repeaters and allows to reduce the power and area demands of NoC interconnects while also reducing its buffer needs; • a solution to simplify the design of the NoC by also increasing their performance and reducing their power and area consumption. We propose to replace complex and slow virtual channel-based routers with multiple and flexible small Multi Plane ones. This solution allows us to reduce the area and power dissipation of any NoC while also increasing its performance especially when the resources are reduced. This Thesis has been written in collaboration with the Advanced System Technology laboratory in Grenoble France, and the Computer Science Department at Columbia University in the city of New York.

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Liu, Liheng. "Performance evaluation of direct air-to-ground communication using new radio (5G)." Thesis, KTH, Teknisk informationsvetenskap, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211464.

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Providing mobile broadband (MBB) coverage to passengers in planes (and other yingobjects) has been one of the very important requirements by airline industry for sometime. With the emergence of high-capacity wireless network concepts, there is a renewedeort in dening systems based on 5G (also dened as NR, new radio) for air-to-ground(A2G) communication. When passenger planes have been taken into consideration, a fewhundreds of passengers may need to be supported, thus requiring a high-capacity backhaullink. When 5G is used for such A2G link, beamforming and other advanced physicallayer techniques can be used between the ground stations and ying objects to obtainhigh-data rate and reliable new radio link. This masters thesis work includes link andsystem level evaluations of such NR systems when beamforming, large bandwidth, higherantenna gains, coordination between ground stations, etc., are deployed. The evaluationswere carried out in Ericsson's internal state-of-the-art simulators. The study providesbaseline for system design principles for future A2G system based on NR. Also a properpropagation model for A2G communication has been identied and beamforming solutionwith other related techniques that could be used in A2G scenario have been investigated.
Att tillhandahålla mobil bredbandstäckning till passagerare i flygplan (samt andraluftburna föremål) har varit ett viktigt krav från flygsindustrin på senare tid. Medframväxten av trådlösa nätverkskoncept med hög kapacitet har en förnyad insats uppståttför att definiera system baserade på 5G (också kallat New Radio (NR)) för Airplane-to-Ground (A2G) kommunikation. För passagerarplan så kan hundratals passagerare behövatäckning, vilket kräver en backhaul-länk med hög kapacitet. När 5G används för en sådanA2G-länk så kan såkallad lobformning och andra avancerade tekniker användas mellanmarkstationerna och flygande objekt för att erhålla hög datahastighet och tillförlitlig radiolänk. I denna uppsats ingår länk- och systemnivåutvärderningar av sådana NR-systemnär lobformning, stor bandbredd, antenn-amplifikation, koordinering mellan markstationeretc utplaceras. Utvärderingarna genomfördes i Ericssons interna simulatorer. Studienger vägledning för principer inom systemdesign för framtida A2G-system baserat på NR.En lämplig utbredningsmodell för radiovågor för A2G-kommunikation har identifieratsoch en metod för lobformning och andra relaterade tekniker som kan användas i A2Gscenariothar också undersökts.

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Tope, Michael A. "Performance evaluation of a cooperative diversity enhanced ad hoc network." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2002. http://library.nps.navy.mil/uhtbin/hyperion-image/02Dec%5FTope.pdf.

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Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, December 2002.
Thesis advisor(s): John C. McEachen, R. Clark Robertson, Daniel M. Rosser. Includes bibliographical references (p. 73-75). Also available online.

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Norling, Kristoffer. "A Performance Evaluation of Secure Distributed Co-Simulation over Wide Area Networks." Thesis, Linköping University, Department of Computer and Information Science, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-15786.

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Different types of models often require different tools and environments to be modeled and simulated. These tools and environments are specialized to handle specific purposes. The models created for these special purposes can then be included in the modeling and simulation of large complex systems. This scenario increases the motivation to use a co-simulation technique. Co-simulation allows for coupling of different simulators into one coherent simulation. Different parts of a system are often modeled by different departments within an enterprise or by subcontractors. Since the models often are describing enterprises’ primary know-how they become important business assets. This raises the need for a secure modeling and simulation approach. This thesis discusses different approaches regarding how to securely simulate and distribute models. We focus on a distributed co-simulation approach over wide area networks (WANs), using transmission line modeling (TLM). The approach is tested in an experimental environment at Linköping University, Sweden, and by real condition co-simulations between Sweden and Australia. A series of experiments are conducted using a simulated WAN environment and the results are put in relation to the real encrypted simulations between Sweden and Australia. We measure the performance during the simulations and evaluate the results. We observe that by distributing the co-simulation we suffer from performance losses. These losses and what parameters cause them is our primary emphasis in the evaluation. We also see that there are two types of parameters that affect the total simulation time in the distributed environment. First there are parameters that belong to the models, and then there are parameters that belong to the WAN environment. We conclude that several of the parameters have effect on the total simulation time. Especially the network delay (latency) has a significant impact.

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Zhao, Jian. "Performance modeling and evaluation of digital video over wireless networks /." View Abstract or Full-Text, 2003. http://library.ust.hk/cgi/db/thesis.pl?COMP%202003%20ZHAO.

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Thesis (Ph. D.)--Hong Kong University of Science and Technology, 2003.
Vita. Includes bibliographical references (leaves 149-160). Also available in electronic version. Access restricted to campus users.

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Yellakonda, Amulya. "DESIGN AND IMPLEMENTATION OF RICH COMMUNICATION SERVICE SCENARIO REPLAYER AND PERFORMANCE EVALUATION OF APPLICATION SERVICE." Thesis, Blekinge Tekniska Högskola, Institutionen för kommunikationssystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-10846.

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Rich Communication Services(RCS) program is a GSM Association (GSMA) initiative to create inter-operator communication services based on IP Multimedia Subsystem (IMS) . This initiative came up as the Global Telecom Operators ́response to the decline in their revenues and to help compete ’Over The Top’(OTT) service providers such as Viber, whatsapp, etc. RCS is an universal standard, making it inter-operable between mul- tiple service providers unlike OTT services with closed communities. RCS services use IMS as the underlying architecture with a RCS stack imple- mented into Android background service which offers high level API. For the purpose of testing RCS stack functionality which is usually affected by external dependencies like third party vendors, or ISP customizations in real telecommunication scenario, there is a persistent demand for scenario replay tools that can recreate the range of test conditions similar to those experienced in live deployments. There is also a need to evaluate the per- formance of service provided by application servers in the network in-order to predict the factors affecting the RCS service in general. In this work, we propose a tool to address the RCS scenario repro- duction in a test environment. The tool is implemented within an automated test environment with full control on interaction with the RCS stack, hence the ability to replay the scenario in a controlled fashion. To achieve the goal, the tool replays trace interactively with the RCS stack in a stateful manner , it ensures no improper packet generation which is critical feature for test environments where protocol semantics accuracy is fundamental. A detailed demonstration of how the tool can be deployed in test environ- ments is stated. A novel approach is used to validate the effectiveness of the replayed scenario, the sequence of events and states are compared to those from the recorded scenario using a call-back service to indicate the state. The replayed scenario showed strong relationship with the recorded RCS scenario. The paper also presents a performance evaluation of Application service by considering the request-reponse times of Network Registration procedure. The obtained results show that the average time taken for the Registration process is 555 milliseconds and in few instances there exists larger deviations from this average value showing the faulty behavior of the Server which is most crucial during the debugging process for the developers.

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Kirsal, Yonal. "Modelling and performance evaluation of wireless and mobile communication systems in heterogeneous environments." Thesis, Middlesex University, 2013. http://eprints.mdx.ac.uk/12174/.

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It is widely expected that next generation wireless communication systems will be heterogeneous, integrating a wide variety of wireless access networks. Of particular interest recently is the integration of cellular networks (GSM, GPRS, UMTS, EDGE and LTE) and wireless local area networks (WLANs) to provide complementary features in terms of coverage, capacity and mobility support. These different networks will work together using vertical handover techniques and hence understanding how well these mechanisms perform is a significant issue. In this thesis, these networks are modelled to yield performance results such as mean queue lengths and blocking probabilities over a range of different conditions. The results are then analysed using network constraints to yield operational graphs based on handover probabilities to different networks. Firstly, individual networks with horizontal handover are analysed using performability techniques. The thesis moves on to look at vertical handovers between cellular networks using pure performance models. Then the integration of cellular networks and WLAN is considered. While analysing these results it became clear that the common models that were being used were subjected to handover hysteresis resulting from feedback loops in the model. A new analytical model was developed which addressed this issue but was shown to be problematic in developing state probabilities for more complicated scenarios. Guard channels analysis, which is normally used to give priority to handover traffic in mobile networks, was employed as a practical solution to the observed handover hysteresis. Overall, using different analytical techniques as well as simulation, the results of this work form an important part in the design and development of future mobile systems.

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Schütte, Miriam [Verfasser], and Klaus M. [Akademischer Betreuer] Schmidt. "Communication, delegation and performance evaluation in organizations / Miriam Schütte. Betreuer: Klaus M. Schmidt." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2013. http://d-nb.info/1045561444/34.

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Sheta, Khalid H. "Design and performance evaluation of techniques for multicasting support in broadband communication networks /." The Ohio State University, 1997. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487947501134772.

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Nassr, Husam, and Kurt Kosbar. "PERFORMANCE EVALUATION FOR DECISION-FEEDBACK EQUALIZER WITH PARAMETER SELECTION ON UNDERWATER ACOUSTIC COMMUNICATION." International Foundation for Telemetering, 2017. http://hdl.handle.net/10150/626999.

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This paper investigates the effect of parameter selection for the decision feedback equalization (DFE) on communication performance through a dispersive underwater acoustic wireless channel (UAWC). A DFE based on minimum mean-square error (MMSE-DFE) criterion has been employed in the implementation for evaluation purposes. The output from the MMSE-DFE is input to the decoder to estimate the transmitted bit sequence. The main goal of this experimental simulation is to determine the best selection, such that the reduction in the computational overload is achieved without altering the performance of the system, where the computational complexity can be reduced by selecting an equalizer with a proper length. The system performance is tested for BPSK, QPSK, 8PSK and 16QAM modulation and a simulation for the system is carried out for Proakis channel A and real underwater wireless acoustic channel estimated during SPACE08 measurements to verify the selection.

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Schütte, Miriam Margarete [Verfasser], and Klaus M. [Akademischer Betreuer] Schmidt. "Communication, delegation and performance evaluation in organizations / Miriam Schütte. Betreuer: Klaus M. Schmidt." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2013. http://nbn-resolving.de/urn:nbn:de:bvb:19-163574.

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Lyamin, Nikita. "Performance evaluation of C-ACC/platooning under ITS-G5 communications." Licentiate thesis, Högskolan i Halmstad, Centrum för forskning om inbyggda system (CERES), 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-32320.

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Intelligent Transport Systems (ITS) are aiming to provide innovative services related to different modes of transport and traffic management, and enable various users to be better informed and make safer, more coordinated and smarter use of transport networks. Cooperative-ITS (C-ITS) support connectivity between vehicles, vehicles and roadside infrastructure, traffic signals as well as with other road users. In order to enable vehicular communications European Telecommunication Standards Institute (ETSI) delivered ITS-G5 -- a of set of C-ITS standards. Considering the goals of C-ITS, inter-vehicle communications should be reliable and efficient. In this thesis we study the performance, efficiency, and dependability of ITS-G5 communications for Cooperative adaptive cruise control (C-ACC) and platooning C-ITS applications. We provide an overview of currently available and ongoing standardization targeting communications in C-ACC/platooning. We study the performance of ITS-G5 beaconing in a C-ACC/platooning scenario, where we show that its performance may deteriorate when implemented in cooperative driving applications due to the kinematic-dependent design of the message triggering mechanism. We explain in detail the cause of this phenomenon and test it for a wide range of parameters. Also, we study the influence of different available ITS-G5 legitimate setups on the C-ACC/platooning fuel efficiency and demonstrate that proper communication setup may enhance fuel savings. This thesis also proposes a jamming denial-of-service attack detection algorithm for platooning. The main advantage of our detector is its short learning phase that not exceed a second and low detection delay of a few hundreds of milliseconds. Under some assumptions, the proposed algorithm demonstrates the ability to detect certain types of attacks with average probability above 0.9.
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Thurston, Michael J. "A pragmatic view of MANET performance evaluation and design of a prototype MAC level routing algorithm." Link to electronic thesis, 2003. http://www.wpi.edu/Pubs/ETD/Available/etd-0108103-122903.

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Yoo, Jin Jung D. "Performance evaluation of a low cost processor with wireless connectivity." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4269.

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Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (July 17, 2006) Includes bibliographical references.

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Vu, Hoang. "Performance evaluation of dynamic channel allocation in a TDMA cellular radio system." Thesis, University of Liverpool, 1995. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.262606.

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Ho, Si Meng. "Web visualization for performance evaluation of e-Government." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2492851.

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Munasinghe, Kumudu S. "VPN over a wireless infrastructure evaluation and performance analysis /." View thesis, 2005. http://library.uws.edu.au/adt-NUWS/public/adt-NUWS20050920.141716/index.html.

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Thesis (M.Sc. (Hons.)) -- University of Western Sydney, 2005.
A thesis submitted in fulfillment of the requirements for the award of the degree Master of Science (Honours) to the University of Western Sydney on March 2005. Includes bibliography.

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Bohannan, Chad Brian. "Performance evaluation of routing protocols for QOS support in rural mobile ad hoc networks." Thesis, Montana State University, 2008. http://etd.lib.montana.edu/etd/2008/bohannan/BohannanC0508.pdf.

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We evaluate several routing protocols, and show that the use of bandwidth and delay estimation can provide throughput and delay guarantees in Mobile Ad Hoc Networks (MANETs). This thesis describes modifications to the Dynamic Source Routing (DSR) protocol to implement the Quality Aware Source Routing (QASR) network routing protocol operating on an 802.11e link layer. QASR network nodes exchange node location and flow reservation data periodically to provide information necessary to model and estimate both the available bandwidth and the end-to-end delay of available routes during route discovery. Bandwidth reservation is used to provide end-to-end Quality of Service, while also utilizing the differentiated Quality of Service provided by the 802.11e link layer. We show that QASR performs significantly better in several performance metrics over the DSR and the Ad-Hoc On-Demand Distance Vector (AODV) protocols, and performs more consistently in all quality metrics when traffic demand exceeds network capacity.

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Karkatzounis, Konstantinos. "Performance evaluation of different jamming strategies over uncoded noncoherent fast FH/MFSK communication systems." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Sep%5FKarkatzounis.pdf.

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SILVA, ANDRE LUIZ GONCALVES DA. "PERFORMANCE EVALUATION OF DVB-RCS PROTOCOL FOR MULTIPLE ACCESS IN SATELLITE COMMUNICATION SYSTEM CHANNELS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2003. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=4731@1.

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COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
Neste trabalho é feito um estudo sobre o desempenho de protocolos de múltiplo acesso adaptativos utilizados em redes via satélite. Inicialmente é apresentado um histórico destes protocolos de múltiplo acesso, descrevendo-se seus fundamentos e incluindo os principais protocolos utilizados atualmente. Em seguida, o protocolo denominado DVB-RCS é descrito e analisado em detalhe e sua aplicação é avaliada em uma rede interativa via satélite utilizando o simulador de redes Opnet. O modelo simulado é o de uma rede VSAT constituída de um grande número de estações terrenas, um satélite e uma estação Hub. São considerados vários tipos de tráfego: tráfego CBR, para transmissão de voz, tráfego VBR para vídeo e UBR para tráfego HTTP e transmissão de dados em geral. Os modelos de tráfego utilizados se basearam na modelagem tradicional de fontes on-off e, no caso de tráfego HTTP, o modelo foi o mesmo adotado para avaliação do sistema UMTS (Universal Mobile Telecommunications System). Para cenários correspondentes a diferentes composições de tráfego, é avaliada a vazão média e o atraso na reserva de recursos, procurando-se determinar critérios para dimensionamento da rede, como a composição de tráfego adequada a cada situação.
In this work, we study the performance of adaptive multiple access protocols used in satellite networks. Firstly a survey of such protocols is presented, describing their basic characteristics and including the main protocols used nowadays. Then, the protocol DVB-RCS is described and analyzed in detail and its applications to an interactive satellite network is evaluated using the Opnet network simulator. The simulated model is the one of a VSAT network with a large number of earth stations, a satellite and a Hub station. Several types of traffic source are considered: CBR traffic for voice transmission, VBR traffic for video stream transmission and UBR traffic for HTTP traffic and general data transmission. The traffic models are based on traditional on-off source and, for HTTP, the model is the one adopted for evaluation of the UMTS (Universal Mobile Telecommunications System). For scenarios corresponding to different traffic compositions, the average throughput and resource reservation delay, seeking to design criteria for the network, e.g. the most appropriate traffic composition for each situation.

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Goni, Usman S. "Performance evaluation of a direct sequence CDMA system for future mobile radio networks." Thesis, University of Liverpool, 1994. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.339731.

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Ni, Xian Electrical Engineering &amp Telecommunications Faculty of Engineering UNSW. "Performance evaluation of ETX on grid based wireless mesh networks." Publisher:University of New South Wales. Electrical Engineering & Telecommunications, 2008. http://handle.unsw.edu.au/1959.4/41016.

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In the past few years Wireless Mesh Networks (WMNs) have developed as a promising technology to provide flexible and low-cost broadband network services. The Expected Transmission Count (ETX) routing metric has been put forward recently as an advanced routing metric to provide high QoS for static WMNs. Most previous research in this area suggests that ETX outperforms other routing metrics in throughput and efficiency. However, it has been determined that ETX is not immune to load sensitivity and route oscillations in a single radio environment. Route oscillations refer to the situation where packet transmission switches between two or more routes due to congestion. This has the effect of degrading performance of the network, as the routing protocol may select a non optimal path. In this thesis we avoided the route oscillation problem by forcing data transmission on fixed routes. This can be implemented in the AODV (Ad hoc On-demand Distance Vector) protocol by disabling both error messages and periodic updating messages (the HELLO scheme). However, a critical factor for our approach is that ETX must determine a high quality initial route in AODV. This thesis investigates whether the ETX metric improves initial route selection in AODV compared to the HOPS metric in two representative client-server applications: the Traffic Control Network (TCN) and the Video Stream (VS) network. We evaluate the ETX and HOPS metrics in a range of scenarios which possess different link qualities and different traffic loads. We find the ETX metric greatly improves initial route selection in AODV compared to the HOPS in the network in which only single flow exists. For networks in which there are multiple simultaneous flows, ETX behaves similar to HOPS in initial route selection. Based on these results, we find the solution of route stabilization to route oscillations in the context of ETX is only useful in the single flow case. To address this problem, we propose a modified solution of repeatedly broadcasting RREQ (Route Request) packets. Simulation results show that our modified solution allows ETX to be useful in the initial route selection in both single flow and multiple simultaneous flows cases.

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Cheung, Kin Pong. "Performance evaluation of scheduling algorithms on Bluetooth piconet and scatternet network /." View Abstract or Full-Text, 2002. http://library.ust.hk/cgi/db/thesis.pl?COMP%202002%20CHEUNG.

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Thesis (M. Phil.)--Hong Kong University of Science and Technology, 2002.
Includes bibliographical references (leaves 63-66). Also available in electronic version. Access restricted to campus users.

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Liang, Tianning. "Performance Evaluation of a LEO Mobile Satellite System Integrated with Intelligent-Transportation-System Networks." Thesis, Université d'Ottawa / University of Ottawa, 2015. http://hdl.handle.net/10393/32028.

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In Intelligent Transport Systems (ITS), the unavailable Road Side Unit (RSU) becomes an increasing serious safety-related problem because of its important role in ITS. However, there is no existing method to solve this problem effectively and stably nowadays. To solve the unavailable RSU problem, a novel 2-tier integrated communication system is proposed in this thesis to address the issue of unavailable RSU in ITS. Compared to some other solutions proposed in the previous research works, which mostly focus on improving the system performance by adjusting parameters of vehicular ad-hoc network among vehicles, the proposed 2-tier communication network, called ITS-LEO Integrated System (ILIS), is composed of conventional ITS system and Low Earth Orbit (LEO) mobile satellite system (MSS), where the LEO MSS is utilized as the complementary network when the RSU is unavailable. Since the LEO MSS primary message will get affected when overflowing messages from ITS to LEO MSS, we prioritize LEO MSS primary message over the overflowed message to minimize the effect, which is based on that the emergency message (EMsg) is given higher priority over routine message (RMsg) to get access to the channel in ITS. To optimize the utility of network resource, two different overflowing mechanisms are proposed in ILIS to improve system efficiency under different traffic density. Furthermore, we propose a bandwidth reservation protection mechanism for ILIS to increase the ITS network performance. A real-time simulation program in C++ is developed to evaluate the performance of ILIS in terms of Packet Loss Rate (PLR) and Delay, and simulation results show that adding LEO MSS as a complementary network to ITS is an effective way to solve the problem of an unavailable RSU.

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Arya, Vivek. "Analysis, Design and Performance Evaluation of Optical Fiber Spectrum-Sliced WDM Systems." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30584.

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This dissertation investigates the design and performance issues of a recently demonstrated technique, termed as spectrum-slicing, for implementing wavelength-division-multiplexing (WDM) in optical fiber systems. Conventional WDM systems employ laser diodes operating at discrete wavelengths as carriers for the different data channels that are to be multiplexed. Spectrum-slicing provides an attractive low-cost alternative to the use of multiple coherent lasers for such WDM applications by utilizing spectral slices of a broadband noise source for the different data channels. The principal broadband noise source considered is the amplified spontaneous emission (ASE) noise from an optical amplifier. Each slice of the spectrum is actually a burst of noise that is modulated individually for a high capacity WDM system. The stochastic nature of the broadband source gives rise to excess intensity noise which results in a power penalty at the receiver. One way to minimize this penalty, as proposed and analyzed for the first time in this work, is to use an optical preamplifier receiver. It is shown that when an optical preamplifier receiver is used, there exists an optimum filter bandwidth which optimizes the detection sensitivity (minimizes the average number of photons/bit) for a given error probability. Moreover the evaluated detection sensitivity represents an order of magnitude ( > 10 dB) improvement over conventional PIN receiver-based detection techniques for such spectrum-sliced communication systems. The optimum is a consequence of signal energy fluctuations dominating at low values of the signal time bandwidth product (m), and the preamplifier ASE noise dominating at high values of m. Operation at the optimum bandwidth renders the channel error probability to be a strong function of the optical bandwidth, thus providing motivation for the use of forward error correction coding (FEC). System capacity (for BER = ) is shown to be 23 Gb/s without coding, and 75 Gb/s with a (255,239) Reed Solomon code. The effect of non-rectangular spectra on receiver sensitivity is investigated for both OOK and FSK transmission, assuming the system (de)multiplexer filters to be N'th order Butterworth bandpass. Although narrower filters are recommended for improving power budget, it is shown that system penalty due to filter shape may be kept < 1 dB by employing filters with N > 2. Moreover spectrum-sliced FSK systems using optical preamplifier receivers are shown, for the first time, to perform better in a peak optical power limited environment. Performance-optimized spectrum-sliced WDM systems have potential use in both local loop and long-distance fiber communication systems which require low-cost WDM equipment for high data rate applications.
Ph. D.

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Feuerstein, Martin J. "Performance evaluation of a spread spectrum local area position location system." Diss., Virginia Tech, 1990. http://hdl.handle.net/10919/39073.

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The primary objective of this research was the investigation of position location technologies suitable for use in construction automation applications. Ground based radio frequency spread spectrum techniques were chosen due to their relatively low cost, ease of implementation, and all weather capability. Two types of spectral spreading were examined: frequency hopping and direct sequence. The error performance capabilities of spread spectrum position location systems were studied systematically through theoretical analysis, a series of experimental tests, and by the development of a computer simulation package. A small scale experimental test was conducted as a proof of concept and a test of the prototype hardware. The small scale test was also used to estimate parameters of the computer simulation program. Later, a full scale test was conducted at a site approximately the size of a typical construction project. Computer simulations of the system performance were found to be in good agreement with the experimental results. The position error performance of a frequency hopping phase Ineasurenlent type position location system was determined using theoretical, simulation, and experimental means. The primary limitation to position accuracy was found to be propagation channel induced errors. By employing nonlinear filtering methods combined with robust estimation techniques, position error distributions which exceed the performance of classic least squared error methods have been achieved. The relationship between vertical and horizontal errors for practical systems has been determined. Computer simulations have provided estimates of the position accuracy of a direct sequence system which combines time domain techniques for ambiguity resolution determination and phase measurement for fine position. For the first time, phase error distributions of hyperbolic multilateration systems in multipath environments have been studied. The computer simulation tools which have been developed and verified experimentally can be used to analyze the performance of future radio position location systems.
Ph. D.

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