Dissertations / Theses: 'Node to Node Communication'

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Kennedy, B. Scott. "Reconfigurable multi-node wireless communication testbed." [Gainesville, Fla.] : University of Florida, 2004. http://purl.fcla.edu/fcla/etd/UFE0004832.

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Rosén, Anders. "Embedded Communication Channel for Node Communication in WDM Networks." Thesis, KTH, Skolan för informations- och kommunikationsteknik (ICT), 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-209167.

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Optical Transport Network is a set of Optical Network Elements (NE) connected by optical fiber links able to provide support for optical networking using Wavelength-Division Multiplexing (WDM). In order to be able to introduce link-level applications that require NE-to-NE communication in a packet-optical network, an embedded communication channel is needed. Examples of such applications are dual-ended protection, remote configurationand path trace. By implementing a NE-to-NE communication channel, the exchange of commands and information will allow for implementation of applications that will increase the data link stability in the network. The purpose of this work has been to prove the feasibility of such a channel. This thesis discusses the possibilities of implementing such a channel adjusted to Transmode's layer 1 products without causing disturbance inthe regular traffic or affecting any existing embedded communication. It also proves the channels function in a proof-of-concept manner by demonstrating a simple Path trace application run upon an implementation of the channel on hardware. The chosen solution is an Embedded Communication Channel driver intended to provide termination points for an Embedded Communication Channel (ECC), supervising the connectivity of the channel and relay messages to applications. This thesis project has been carried out at Infinera Corporation (earlier Transmode Systems AB) during summer/autumn 2015.

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Nazrul, Shahbaz. "Survivability Analysis of Two Specific 16-Node, 24-Link Communication Networks." Thesis, Virginia Tech, 1998. http://hdl.handle.net/10919/36858.

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A highly survivable communication network is desirable, as service disruption is usually not tolerated. In this thesis we mainly investigate and discuss the survivability of two specific communication networks, termed topology 1 and 2, under usual network failures. The survivability of the networks mainly comes from their structure. Both topologies have different routes between all source-destination pairs, which gives the networks high route diversity. In fact, both topologies considered are regular networks with connectivity 3. Discussion starts by defining several network properties, such as average route-length and link and node utilization, for the fault-free condition. Alterations of these properties are investigated when a network failure takes place. Using the results for fault-free and faulty situations, a comparison is made between the topologies. Topologies 1 and 2 are also compared with other standard topologies like full ring, square grid and star topologies. Another regular network topology called the star-ring topology is also introduced and investigated for the same properties. Enough insight is given to devise an optimal re-routing strategy when a network failure takes place. A new idea of static routing strategy called the Static Disjoint Routing Strategy is introduced. This disjoint routing strategy is proven to be close in performance to that of traditional Dynamic Shortest Routing with a considerable gain in ease of operation. The disjoint routing table is used to investigate whether any link or node becomes over utilized in faulty situations. On the whole both topologies were found to be highly survivable structures with reasonable cost.
Master of Science

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Dingel, Janis. "Communication theory applied to selected problems in computational genetics." kostenfrei, 2009. https://mediatum2.ub.tum.de/node?id=796739.

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Murray, Don C. Pratt Christopher L. "Remote network administration of the SEANET communication node system /." Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1998. http://handle.dtic.mil/100.2/ADA355948.

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Thesis (M.S. in Information Technology Management) Naval Postgraduate School, September 1998.
"September 1998." Thesis advisor: Rex Buddenberg. Includes bibliographical references (p. 139-140). Also available online.

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Murray, Don C., and Christopher L. Pratt. "Remote network administration of the SEANET communication node system." Thesis, Monterey, California. Naval Postgraduate School, 1998. http://hdl.handle.net/10945/8912.

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Approved for public release; distribution is unlimited
Maritime data communications are expensive and of limited capacity. Currently there is no established infrastructure to support Internet connectivity for sea-going vessels. The SeaNet program is investigating maritime networking solutions. One aspect of the SeaNet program is promoting remote network management. Remote network management will provide the maritime research community with a flexible and cost-effective tool for monitoring sea based assets. The objective of this thesis is to investigate remote network management over a satellite connection in support of the SeaNet programs goals. To research the potential for remote network management, the Naval Postgraduate School has developed its own SeaNet laboratory. This laboratory simulates both the shipboard and shore-based infrastructure of the SeaNet program and conducts remote network management on these components. This thesis discusses the SeaNet program, network management concepts, the NPS SeaNet laboratory, research findings and recommendations for fliture research. Remote Network Management of the SeaNet Control Node system is possible, however, continued research in this area is needed

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Rahmani, Mehrnoush. "A resource-efficient IP-based network architecture for in-vehicle communication." München Verl. Dr. Hut, 2009. http://mediatum2.ub.tum.de/node?id=683840.

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Moshiri, Hesam. "Implementation of a Generic Gateway as a Multipurpose Communication Node." Thesis, Högskolan i Halmstad, Sektionen för Informationsvetenskap, Data– och Elektroteknik (IDE), 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-24840.

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Steering and navigation systems play an essential role in governing today’s leisure boats. CPAC Systems AB, a subsidiary of Volvo AB, satisfies a large part of the global market needs for this kind of products. CPAC Systems, among others, manufactures a well-known “steer-by-wire” (SBW) control system, the “Electronic Vessel Control” (a.k.a. EVC). The need to connect the EVC to systems and devices designed by other companies resulted in the development of “gateway” devices, which have a primary role in preserving the integrity of the overall system architecture. Whenever the SBW communicates with external products, gateways are used as electric isolators and protocol translators, in order to protect the integrity of the SBW function. Today, a number of different gateway devices are required to match the different interfaces to which the CPAC’s EVC system has to be connected. This thesis aims to tackle the huge diversification of the requirements and evaluates the possibility of designing a “single” product that satisfies most of the requirements. In addition to that, the work aims to design a flexible device that could be easily updated to comply with the potential needs of the incoming applications. This isbeneficial in terms of both technology and cost-efficiency. Existing gateway products are designed to fulfill the assigned tasks or just to do a specific protocol conversion and apart from this significant difference with a generic gateway, they have some limitations concerning environmental conditions and prospective upgrades. Therefore designing, testing and implementation of one multifunctional gateway to be applicable as a multipurpose communication node to cover several functionalities, would be beneficial. Several challenges arose in designing the generic gateway device, such as: hardware design with a limited number of connection I/Os (solution is limited to 20 I/Os, whereas current gateway products require as many as 35 I/Os), robustness, final cost and power consumption. The contribution of the thesis was to analyse current gateway products, to design the hardware (Schematic and PCB), to implement the software, to debug the operation, to verify of the designed hardware to ensure the operation of each part. For gathering test results and investigation of communication or instruction signals, industrial equipment like digital oscilloscope and CAN analyser have been used to prove the operation of the device which are demonstrated in the “design tests” part. In addition, robustness of the gateway has been tested against several industrial test parameters, such as temperature variations, isolation, power supply robustness and typical power consumption. The results of these tests are iscussed in the “robustness tests” part. By fulfilling all of these steps and collaboration with the company team, satisfactory results have been achieved.

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Li, Houmin Thomas Gwynedd A. "Geotextile antenna design for mobile phone cooperative communication relay node." Auburn, Ala., 2008. http://hdl.handle.net/10415/1498.

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Ragab, A. H. M. "A high capacity multiprocessor X.25 packet switching node." Thesis, University of Essex, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355389.

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Gadde, Srimanth. "Graph Partitioning Algorithms for Minimizing Inter-node Communication on a Distributed System." University of Toledo / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1376561814.

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Shahnaz, Ambreen. "Approximating node-weighted Steiner subgraphs for multicast communication in wireless networks." Thesis, University of Leicester, 2012. http://hdl.handle.net/2381/10837.

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We are motivated by the problem of computing multicast routing structures in wireless ad-hoc networks modelled by special classes of graphs including unit disk graphs, quasi-unit disk graphs and (λ + 1)-claw-free graphs. Multicast communication can be established by a tree known as Steiner tree. Wireless ad-hoc networks must operate using limited resources, therefore, the suitability of nodes for inclusion in a Steiner tree can vary widely between different nodes. We model this by assuming that each node of the network is assigned a weight that represents the cost of including it in the Steiner tree. Our goal is to compute a Steiner tree with minimum total node weight. However, in scenarios where nodes and links are not reliable, a tree has the drawback that it can be disconnected by the failure of even a single link or node in the network. Therefore, we also consider various fault-tolerant routing structures called 2-edge-connected Steiner subgraphs, k-edge-connected Steiner subgraphs, 2-vertex-connected Steiner subgraphs, and 2-edge-connected group Steiner subgraphs. The problems we consider are NP-hard, so we are interested in algorithms that compute provably good approximate solutions in polynomial time. We present a generalization of Steiner subgraph problems referred to as the node-weighted δ-Steiner subgraph problem, where δ represents connectivity requirements. We present an algorithm with approximation ratio 0.5dρ for the node-weighted δ-Steiner subgraph problem, where d is the bounded maximum degree of the solution subgraph, and ρ is the approximation ratio of the edge-weighted version of the δ-Steiner subgraph problem. We then shown how to construct solution subgraphs of bounded maximum degree d in several graph classes for our problem variants. As a result, we obtain algorithms for the problems we consider, on graph classes that admit subgraphs of small degree, whose approximation ratios are better than the best known ratios for the same problems on general graphs.

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Thesnaar, Emile Jacobus. "Development of a radiation resistant communication node for satellite sub-systems." Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/86510.

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Thesis (MEng)--Stellenbosch University, 2014.
ENGLISH ABSTRACT: Within a complex electronic system, sub-system communication forms the backbone of the functionality of any satellite. It allows multiple processors to run simultaneously and data to be shared amongst them. Without it, a single processor would have to control the entire satellite. Not only would such a design then be overly complicated, but the processor would also not have sufficient capacity to service all the components efficiently. Furthermore the detrimental effects that radiation have on integrated circuits are well documented and can be anything from a single bit flip to a complete integrated circuit failure. If not repaired, a failure on a sub-system communication bus could lead to the loss of the entire satellite. Die goal is to create more radiation resistant Controller-Area-Network (CAN) node. Since a full triple modular redundant design will have a large footprint and high power consumption, a combination of techniques will be applied and tested. The goal is to achieve improved footprint utilisation over triple modular redundancy, while still maintaining good resistance to Single Event Upsets (SEU). By applying simulation, it was sufficiently proven that the implementation of the individual techniques used functioned according to expectations. These techniques included error detection and correction using Hamming Codes, single event transient filter and triple modular redundancy. Having applied these mitigation techniques, the footprint of the CAN controller increased by only 116%. Simulation showed that the Error Detection and Correction and Triple Modular Redundancy worked effectively with the CAN controller, and that the CAN controller could function as originally intended. Using radiation testing, the design proved to be more resistant to SEUs than the unmitigated CAN controller. It was thus shown that through using a combination of mitigation techniques, it is possible to develop an optimal design with a high level of resistance against Single Event Upsets, utilizing a smaller footprint than implementing Triple Modular Redundancy.
AFRIKAANSE OPSOMMING: Sub-stelsel kommunikasie vorm die basis van die funksionaliteit in ’n komplekse elektroniese stelsel soos ’n satelliet. Dit skep die vermoë om veelvoudige verwerkers gelyktydig te laat funksioneer en inligting tussen hulle te deel. Sonder sub-stelsel kommunikasie, sal ’n enkele verwerker die hele sateliet moet beheer. Dit sal nie net die hele ontwerp oorkompliseer nie, maar die verwerker sal ook nie genoeg kapisteit hê om al die komponente effektief te diens nie. Die newe-effekte van bestraling op geïntegreerde stroombane is goed gedokumenteer en kan wissel van ’n enkele omgekeerde bis, tot die vernietiging van die geïntegreerde stroombaan. Indien die fout in die kommunikasiestelsel nie herstel word nie, kan dit lei tot die verlies van die hele sateliet. Die doel is om ’n meer bestraling bestande Controller-Area-Network (CAN) nodus te skep. Aangesien ’n volle drie-dubbele-modulêre-oortollige ontwerp ’n baie groot area beslaan en hoë krag verbruik het, gaan ’n kombinasie van versagting tegnieke toegepas en ge-evalueer word. Die doel is om beter area benutting as die drie-dubble-modulêre-oortollige ontwerp te kry, terwyl ’n goeie weerstand teen foute behoue bly. Deur middel van simulasies is voldoende bewyse gelewer dat die implimentasie van die individuele versagting tegnieke soos verwag funktioneer. Hierdie tegnieke sluit in, fout opsporing en regstelling deur middel van Hamming kodes, enkele geval oorgangs verskynsel filter asook drie-dubbele-modulêre-oortollige ontwerp. Nadat versagting meganismes toegepas is, het die area verbruik van die CAN beheerder toegeneem met slegs 116%. Simulasies het bewys dat Fout Opsporing en Regstelling en Drie-Dubbele-Modulêre-Oortollige ontwerp tegnieke binne die CAN beheerder korrek funktioneer, terwyl die CAN beheerder self funktioneer soos dit oorspronklik gefunksioneer het. Deur middel van bestralingstoetse, is dit bewys dat die ontwerp meer bestand is teen foute geïnduseer deur bestraling as die onbeskermde CAN beheerder. Dit is dus bewys dat deur gebruik te maak van verskeie versagting tegnieke dit moontlik is om ’n optimale ontwerp te implimenteer, met ’n hoë weerstand teen foute, maar met ’n laer area verbruik as die van ’n Drie-dubbele-Modulêre-Oortollige ontwerp.

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Sridhar, Jaidev Krishna. "Scalable Job Startup and Inter-Node Communication in Multi-Core InfiniBand Clusters." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243909406.

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Hayes, Alan James. "Characterisation of cellular communication between an inflammatory site and the draining lymph node." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/8160/.

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In order to track cell migration, the project used a transgenic mouse system which ubiquitously expressed the fluorescent protein kaede that undergoes photo-conversion when exposed to violet or ultraviolet (UV) light. By inducing inflammation in peripheral tissues (e.g. the ear pinna on the hind footpad) and subsequently exposing the tissue to UV light, it was possible to spatiotemporally track the fate of the cells at these tissue sites. The study revealed that tissue resident cells do not constitute the majority of the migratory population and that immune cells must first be recruited to the site of challenge prior to migration. Migration from the site of challenge to the draining lymph node occurs within the first 48 hours post injection and returns to baseline over the following 24 hours. By combining the above approach with the YAe/Eα system to track antigen presentation, the study has also shown that antigen presentation persists for the first 24-36 hours and the majority of cells presenting antigen are CD103+CD11b+ dendritic cells. In collaboration with UCB, CyTOF profiling was performed on the migratory population to identify the diversity of these cells, identifying CD4+ T cells, CD8+ T cells, γδ T cells, B cell and neutrophils in the draining lymph node originating from the injection site. Therefore, it is suggested that the migratory cells work in tandem with one another to control the initiation of adaptive immunity and determine the nature and the magnitude of the immune response. Additionally, the nature of an inflammatory stimulus can alter the magnitude and composition of the migratory population. This study highlights that our current knowledge regarding the initiation of adaptive immunity, in particular, the kinetics and phenotype of the migratory cells, remains limited. Further developing our understanding of the migratory population, antigen presentation and the kinetics of antigen presentation may help to identify new targets for immunomodulation for the treatment of inflammatory disorders or the development of new and improved vaccine adjuvants.

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Chai, Lei. "High Performance and Scalable MPI Intra-node Communication Middleware for Multi-core Clusters." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1236639834.

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Dong, Shaoqiang Agrawal Prathima. "Node placement, routing and localization algorithms for heterogeneous wireless sensor networks." Auburn, Ala, 2008. http://repo.lib.auburn.edu/EtdRoot/2008/SPRING/Electrical_and_Computer_Engineering/Thesis/Dong_Shaoqiang_40.pdf.

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Hensley, Phillip Hayden. "Development and Analysis of a Mobile Node Tracking Antenna Control System." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc1011810/.

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A wireless communication system allows two parties to exchange information over long distances. The antenna is the component of a wireless communication system that allows information to be converted into electromagnetic radiation that propagates through the air. A system using an antenna with a highly directional beam pattern allows for high power transmission and reception of data. For a directional antenna to serve its purpose, it must be accurately pointed at the object it is communicating with. To communicate with a mobile node, knowledge of the mobile node's position must be gained so the directional antenna can be regularly pointed toward the moving target. The Global Positioning System (GPS) provides an accurate source of three-dimensional position information for the mobile node. This thesis develops an antenna control station that uses GPS information to track a mobile node and point a directional antenna toward the mobile node. Analysis of the subsystems used and integrated system test results are provided to assess the viability of the antenna control station.

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Holby, Björn, and Carl-Fredrik Tengberg. "Low Power Current Sensing Node Powered by Harvested Stray Electric Field Energy." Thesis, Linköpings universitet, Elektroniska Kretsar och System, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-121520.

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In this thesis, the possibility of harvesting energy from a multicore power cableconnected to a power outlet is presented and evaluated. By surrounding a powercable with a conductive material connected to ground, it is shown that the dif-ference in potential between the power cable and the conductive material causesa capacitance which can charge a capacitor that in combination with an energymanagement circuit can be used to wirelessly transmit data with an interval de-pending on factors like the length of the surrounding material and the type ofcable it is placed around. In addition to this, a technique to, in a non-invasiveway, sense whether there is alternating current flowing in a multicore power ca-ble is brought up. The results show that this technique can be used to detectalternating current without having a device connected between the power cableand the power outlet. These two sections combined are used to design a surveil-lance system that should monitor consumer electronics in the home environmentwhere there is a fire hazard. The system should send out a warning signal thatis visible for the homeowner to remind the user to switch off the power of theelectronic devices before leaving home.

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Mancera-Mendez, German Andres. "Ad hoc wireless networks flooding and statistical understanding of node movement /." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file 2.31 Mb., 68 p, 2006. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&res_dat=xri:pqdiss&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&rft_dat=xri:pqdiss:1435817.

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Badokhon, Alaa. "An Adaptable, Fog-Computing Machine-to-Machine Internet of Things Communication Framework." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1492450137643915.

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Arrowsmith, Timothy William. "A NETWORK PROCESSING NODE FOR LIGHT UNMANNED AIRCRAFT." UKnowledge, 2007. http://uknowledge.uky.edu/gradschool_theses/422.

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Over the last decade, research into unmanned and autonomous vehicles has greatly increased. With applications ranging from science and exploration to humanitarian and military efforts, the rising need for autonomous vehicles demands constant innovation and growth. The Intelligent Dependable Embedded Architectures (IDEA) lab at the University of Kentucky is continually launching research oriented programs [1]. A few key projects focus on the development of Unmanned Aerial Vehicles (UAV). Through this research, at the University of Kentucky, the need to develop a reliable, lightweight, node based hardware for use in light UAVs and other unmanned and autonomous vehicles became apparent. This paper addresses the design and implementation of a network processing node for light UAVs. This system utilizes a Controller Area Network (CAN) noise tolerant communications bus, a low power ZigBee Wireless Network for expanded inner plane communications and Silicon Laboratories C8051F041 microcontrollers to provide the necessary inputs/output and data processing. The final result will be a flight ready light UAV featuring distributed processing nodes to handle the servo communications and controls.

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Wennerström, Hjalmar. "A Node-Link Perspective on the Impact of Local Conditions in Sensor Networks." Doctoral thesis, Uppsala universitet, Avdelningen för datorteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-300168.

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Sensor networks are made up of small battery-powered sensing devices with wireless communication capabilities, enabling the network to monitor the environment in which it is deployed. Through their flexible and cable-free design these networks open up for new deployment scenarios that were previously not plausible such as during a natural disaster. Motivated by scenarios where centralized oversight is not possible the focus of this thesis is to equip nodes with further adaptability to changes in the links it has with other nodes. This is achieved through contributions in three areas focusing on observations from a node-link perspective. First, the impact the local environment has on the nodes is explored by deploying a sensor network outdoors next to a meteorological station to correlate the variations in link quality to the changes in the environment. The work identifies temperature as the main factor, where through further investigations in a controlled setting, a linear relationship between the decrease in signal quality and the increase in temperature is described. Secondly, the thesis address how nodes in a sensor network can be motivated to exchange data by modeling it as a game. The game theoretic design is motivated by the absence of any centralized control and focus on the nodes as individual users in the network. The presented design motivates the selfish nodes to participate in the exchange of sensor data, showing that it is the best strategy. Lastly, by exploring and understanding how connections in a mobile sensor network occur, nodes are given more flexibility to determine how to send and sample sensor data. This adaptability to contact occurrences is shown to provide better ways of sending data by selecting higher quality links as well as making sampling more energy preserving by reducing the rate in the vicinity of other nodes.
CNDS
WISENET

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Kanaan, Muzaffer. "Node density and quality of estimation for infrastructure-based indoor geolocation using time of arrival." Worcester, Mass. : Worcester Polytechnic Institute, 2008. http://www.wpi.edu/Pubs/ETD/Available/etd-041508-165035/.

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Fernandez-Fernandez, Alvaro. "Differentiated dependability of the 3LIHON concept with main focus on internal node architecture." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for telematikk, 2012. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-16789.

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Hybrid optical networks are considered as the most promising architectures for future optical networks, in order to achieve both better cost and performance. Dependability is a topic of increasing interest in order to provide the Quality of Service (QoS) expected for future optical networks. Recently, the 3-Level Integrated Hybrid Optical Network (3-LIHON) has been proposed as a new concept for future optical core networks, including different transport technologies to support a wide range of services. Due to the wide range of future telecommunication services foreseen for next generation optical backbone networks, the 3-LIHON architecture must be provided with differentiated dependability, in order to offer the availability demanded by the most critical services, as well as to utilize network resources efficiently. By focusing in a single 3-LIHON node, this thesis employs component redundancy to present a differentiated survivability model suitable for the 3-LIHON architecture. Several protection mechanisms for two of the three types of traffic supported by 3-LIHON are proposed in this research work. These mechanisms are analyzed by means of different dependability models, i.e. reliability block diagrams and Markov models; and a numerical evaluation of its unavailability is presented. In addition, simulation results measuring the impact on performance of some mechanisms are also presented. Then, the protection mechanisms are compared and evaluated, taking into account not only its unavailability and performance, but also other considerations such as cost and complexity. Finally, based on this evaluation, the best suited mechanisms are selected.

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Mehta, Hardik. "Design, implementation, and evaluation of node placement and data reduction algorithms for large scale wireless networks." Diss., Available online, Georgia Institute of Technology, 2004:, 2003. http://etd.gatech.edu/theses/available/etd-04072004-180101/unrestricted/mehta%5fhardik%5f200312%5fms.pdf.

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Alla, Sindhu. "A Study of Mobility Models based on Spatial Node Distribution and Area Coverage." Thesis, University of North Texas, 2017. https://digital.library.unt.edu/ark:/67531/metadc984231/.

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Mobile wireless sensor networks are not widely implemented in the real world, even after years of research carried out in this field. One reason is the lack of understanding of the impact that mobility has on network performance. The simulation and emulation of mobile wireless sensor networks is necessary before they are deployed for the real-world applications. This thesis presents a simulation-based study of different mobility models. The total area coverage that depends on the pattern of node movements is observed through simulations. The spatial distribution of node locations is also studied. Various synthetic mobility models available are explored based on their theoretical descriptions. ‘BonnMotion' is used as the network simulator for investigating different mobility scenarios. The results obtained after simulations are imported to MATLAB and the analysis of node movements is done through various plots and inferences from the data. The comparison of mobility models is also discussed based on their spatial node distribution in the simulated scenarios.

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Kihlberg, David, and Amir Ebrahimi. "Wireless Gas Sensor Nodes : With focus on Long Range (LoRa) communication." Thesis, Linköpings universitet, Elektroniska Kretsar och System, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-168669.

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Greenhouse gas emissions in indoor or outdoor areas are dangerous and can have short- or long-term effects on people’s health. There are several methods to monitor the air quality in such environments. This thesis project attempts to design and evaluate a wireless sensor network with two main characteristics such as long range and low power consumption. The sensor network is built upon Long Range Wide Area Network (LoRaWAN) protocol and is composed of sensor nodes and gateways. The sensor nodes are built upon a Raspberry Pi model 3B, a LoRa SX1276 transceiver and gas sensors. The sensors are intended to measure CO2, CH4, temperature, pressure and relative humidity. The collected data is then logged and sent to The Things Network (TTN) via a backhaul connection.

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Rimer, Suvendi Chinnappen. "Energy efficient communication models in wireless sensor and actor networks." Thesis, University of Pretoria, 2012. http://hdl.handle.net/2263/23253.

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Sensor nodes in a wireless sensor network (WSN) have a small, non-rechargeable power supply. Each message transmission or reception depletes a sensor node’s energy. Many WSN applications are ad-hoc deployments where a sensor node is only aware of its immediate neighbours. The lack of a predefined route path and the need to restrict the amount of communication that occurs within the application area impose constraints on WSNs not prevalent in other types of networks. An area of active research has been how to notify the central sink (or monitoring hub) about an event in real-time by utilising the minimum number of messages to route a message from a source node to the destination sink node. In this thesis, strategies to limit communication within a WSN application area, while ensuring that events are reported on and responded to in real-time, is presented. A solution based on modelling a WSN as a small world network and then transmitting an initialisation message (IM) on network start-up to create multiple route paths from any sensor node to one or more sinks is proposed. The reason for modelling a WSN as a small world network is to reduce the number of nodes required to re-transmit a message from a source sensor node to a sink. The purpose of sending an IM at network start-up is to ensure that communication within the WSN is minimised. When routing a message to a static sink, the nodes closest to the static sink receive a disproportionate number of messages, resulting in their energy being consumed earlier. The use of mobile sinks has been proposed but to our knowledge no studies have been undertaken on the paths these mobile sinks should follow. An algorithm to determine the optimum path for mobile sinks to follow in a WSN application area is described. The purpose of an optimum path is to allow more equitable usage of all nodes to transfer an event message to a mobile sink. The idea of using multiple static sinks placed at specific points in the small world model is broadened to include using multiple mobile sinks called actors to move within a WSN application area and respond to an event in real-time. Current coordination solutions to determine which actor(s) must respond to the event result in excessive message communication and limit the real-time response to an event. An info gap decision theory (IGDT) model to coordinate which actor or set of actors should respond to the event is described. A comparison of the small world routing (SWR) model against routing using flooding and gossiping shows that the SWR model significantly reduces the number of messages transmitted within the network. An analysis of the number of IMs transmitted and received at individual node level shows that prudent selection of the hop count (number of additional nodes required to route a message to sink) to a sink node will result in a reduced number of messages transmitted and received per node within the network. The use of the IGDT model results in a robust decision on the actor(s) chosen to respond to an event even when uncertainty about the location and available energy of other actor(s) exists.
Thesis (PhD(Eng))--University of Pretoria, 2012.
Electrical, Electronic and Computer Engineering
unrestricted

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Mouton, A. J. J., C. J. Smith, and G. E. Smith. "An efficient communication interface and protocol for motor protection relays." Journal for New Generation Sciences, Vol 7, Issue 1: Central University of Technology, Free State, Bloemfontein, 2009. http://hdl.handle.net/11462/524.

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Published Article
A company in South Africa is a three-phase induction motor protection relay manufacturer. The function of the protection relay is to capture running data, to provide protection against possible damage, to control an electric motor and to communicate this data to the System Control and Data Acquisition (SCADA) system in a control room. In the case of remote sites e.g. a pump station, the protection relays are used as standalone units. The protection relays are equipped with communication facilities to be used in an instrumentation environment. If a trip occurs or settings need to be changed a technician has to visit the remote site and address the problem. The ideal cost and time effective solution is to perform these tasks remotely via a reliable wireless network. A study was conducted to ascertain the viability of using the standard GSM cellular networks in South Africa to effectively control electric motors and to communicate with the Motor Protection Relays (MPRs) controlling the electric motors in order to determine the status of a motor, settings of the motor, trips that occurred and time of occurrence. It was shown that a node controller could be used to store all the data from various electric motors at a single location. It was also shown that the data from the different electric motors could be analysed at the node controller and that communication can then be initiated from the controller to a responsible person via the GSM network. It was further illustrated that, by making use of the GSM networks in South Africa together with the short message service (SMS), communication and control can be effectively established. SMSs proved to be a reliable means of communication between cellular phones, an embedded network and MPRs. It was shown that software protocols, although slower in communication speed, proved to be reliable and effective for the purpose of transferring information between the node controller and the motor protection relays connected to the electric motors.

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Hoblos, Jalaa. "Selfish Node Misbehaving Statistical Detection with Active MAC Layer NAV Attack in Wireless Networks}." [Kent, Ohio] : Kent State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=kent1164119272.

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32

Magalhães, Marcelo Vellozo. "Adaptive node capability metric to assess the value of networking in a general command and control wireless communication topology." Thesis, Monterey, California. Naval Postgraduate School, 2011. http://hdl.handle.net/10945/5558.

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Approved for public release; distribution is unlimited.
In order to quantify any node's capacity to support optimal information flow within a distributed command and control network, a novel node capability value calculation is developed from first principles. The expression for the node capability value is developed using three fundamental building blocks: data throughput, bandwidth efficiency, and the link margin. The data throughput depends on the average packet arrival rate, the probability of not dropping a packet and the probability of correct receiving a packet at the queue. The bandwidth efficiency depends on the node data rate and the transmission bandwidth, while the link margin is a function of the received and required energy per bit to noise power density. The generalized connectivity integrates the computed node capability value by considering all the distributed network connections scaled by their route length and estimating the characteristic tempo, which is the maximum information exchange rate. The generalized connectivity results reflect the amount and quality of detectable information that the nodes can process and transmit about the network. The results also show how the power and bandwidth efficiency of any specific node compares the power and bandwidth efficiency of all the other nodes. A four-node dynamic scenario is simulated and used to numerically evaluate the expression for the node capability value. Command and control tradeoff issues facing battlespace managers and decision makers are examined by including the networks characteristic tempo into a single observe, orient, decide and act (OODA loop). Also, included in the OODA loop, are action tempos and the command and control speed. Consideration of the influence of three classic Sheridan levels of automation on decision making are used to model the operational impacts via three action tempo tiers: high, medium, and low-action. Input command and control information rates produced the strongest observed influences on aggregate network simulation outputs.

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33

Roa, Rodríguez Rodrigo. "Tiling heuristics and evaluation metrics for treemaps with a target node aspect ratio." Thesis, KTH, Skolan för datavetenskap och kommunikation (CSC), 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-211512.

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Treemaps are a popular space-filling visualization of hierarchical data that maps an attribute of a datum, or a data aggregate, to a proportional amount of area. Assuming a rectangular treemap consisting of nested rectangles (also called tiles), there are multiple possible valid tiling arrangements. A common criterion for optimization is aspect ratio. Nevertheless, treemaps usually consist of multiple rectangles, so the aspect ratios need be aggregated. The basic definition of aspect ratio (width divided by height) cannot be meaningfully aggregated. Given this, a definition of aspect ratio that does not differentiate height from width was suggested. This definition allows for meaningful aggregation, but only as long as there are no large differences in the data distribution, and the target aspect ratio is 1:1. Originally, a target aspect ratio of 1:1 was deemed to be axiomatically ideal. Currently, perceptual studies have found an aspect ratio of 1:1 to lead to the largest area estimation error. However, with any other target this definition of aspect ratio cannot be meaningfully aggregated. This thesis suggests a correction that can be applied to the current metric and would allow it to be meaningfully aggregated even when there are large value differences in the data. Furthermore, both the uncorrected and corrected metrics can be generalized for any target (i.e. targets other than 1:1). Another issue with current evaluation techniques is that algorithm fitness is evaluated through Monte Carlo trials. In this method, synthetic data is generated and then aggregated to generate a single final result. However, tiling algorithm performance is dependant on data distribution, so a single aggregateresult cannot generalize overall performance. The alternative suggested in this thesis is visual cluster analysis, which should hold more general predictive power.All of the above is put into practice with an experiment. In the experiment, a new family of tiling algorithms, based on criteria derived from the results of the perceptual tests in literature,is compared to the most popular tiling algorithm, Squarify. The results confirm that there are indeed vast but consistent value fluctuations for different normal distributions. At least for a target aspect ratio of 1.5, the new proposed algorithms are shown to perform better than Squarify for most use cases in terms of aspect ratio.

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34

Lee, Jongdae. "Performance enhancement of CSMA/CA in powerline communications under heavy traffic and hidden node conditions." [Gainesville, Fla.] : University of Florida, 2008. http://purl.fcla.edu/fcla/etd/UFE0022857.

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35

Horyachyy, Oleh. "Comparison of Wireless Communication Technologies used in a Smart Home : Analysis of wireless sensor node based on Arduino in home automation scenario." Thesis, Blekinge Tekniska Högskola, Institutionen för datalogi och datorsystemteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-14845.

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Context. Internet of Things (IoT) is an extension of the Internet, which now includes physical objects of the real world. The main purpose of Internet of Things is to increase a quality of people’s daily life. A smart home is one of the promising areas in the Internet of Things which increases rapidly. It allows users to control their home devices anytime from any location in the world using Internet connectivity and automate their work based on the physical environment conditions and user preferences. The main issues in deploying the architecture of IoT are the security of the communication between constrained low-power devices in the home network and device performance. Battery lifetime is a key QoS parameter of a battery-powered IoT device which limits the level of security and affects the performance of the communication. These issues have been deepened with the spread of cheap and easy to use microcontrollers which are used by electronic enthusiasts to build their own home automation projects. Objectives. In this study, we investigated wireless communication technologies used in low-power and low-bandwidth home area networks to determine which of them are most suitable for smart home applications. We also investigated the correlation between security, power consumption of constrained IoT device, and performance of wireless communication based on a model of a home automation system with a sensor node. Sensor node was implemented using Arduino Nano microcontroller and RF 433 MHz wireless communication module. Methods. To achieve the stated objectives of this research following methods were chosen: literature review to define common applications and communication technologies used in a smart home scenario and their requirements, comparison of wireless communication technologies in smart home, study of Arduino microcontroller technology, design and simulation of a part of home automation project based on Arduino, experimental measurements of execution time and power consumption of Arduino microcontroller with RF 433 MHz wireless module when transmitting data with different levels of security, and analysis of experimental results. Results. In this research, we presented a detailed comparison of ZigBee, WiFi, Bluetooth, Z-Wave, and ANT communication technologies used in a smart home in terms of the main characteristics. Furthermore, we considered performance, power consumption, and security. A model of a home automation system with a sensor node based on Arduino Nano was described with sleep management and performance evaluation. The results show that the battery lifetime of Arduino in a battery-powered sensor node scenario is determined by the communication speed, sleep management, and affected by encryption. Conclusions. The advanced communication strategy can be used to minimize the power consumption of the device and increase the efficiency of the communication. In that case, our security measures will reduce the productivity and lifetime of the sensor node not significantly. It’s also possible to use symmetric encryption with smaller block size.

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Fuchs, Fabian [Verfasser], and D. [Akademischer Betreuer] Wagner. "Algorithms for Efficient Communication in Wireless Sensor Networks - Distributed Node Coloring and its Application in the SINR Model / Fabian Fuchs. Betreuer: D. Wagner." Karlsruhe : KIT-Bibliothek, 2015. http://d-nb.info/1082294470/34.

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37

Retonda-Modiya, John-Charly. "Development of an embedded system actuator node for intergration into an IEC 61850 based substation automation application." Thesis, Cape Peninsula University of Technology, 2012. http://hdl.handle.net/20.500.11838/1162.

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Thesis submitted in fulfilment of the requirements for the degree Master of Technology: Electrical Engineering in the Faculty of Engineering at the Cape Peninsula University of Technology, 2012
The introduction of the IEC 61850 standard in substations for communication networks and systems by the International Electrotechnical Commission (IEC) in 2003 provided the possibility for communication between devices of different manufacturers. However, the advent of this standard also brought about many challenges associated with it. The challenges introduced by this fairly recent standard of communications in Substation Automation Systems (SAS), and the need for the development of cost effective IEC 61850- compliant devices, motivated the decision of the Centre for Substation and Energy Management Systems within the Electrical Engineering Department of the Cape Peninsula University of Technology to focus on the implementation of the IEC 61850 standard using an embedded hardware platform. The development of an IEC 61850 embedded application requires substantial knowledge in multiple domains such as data networking, software modelling and development of Intelligent Electronic Devices (IEDs), protection of the electrical system, system simulation and testing methods, etc. Currently knowledge about the implementation of the IEC 61850 standard usually resides with vendors and is not in the public domain. The IEC 61850 standard allows for two groups of communication services between entities within the substation automation system. One group utilizes a client-server model accommodating services such as Reporting and Remote Switching. The second group utilizes a peer-to-peer model for Generic Substation Event (GSE) services associated with time-critical activities such as fast and reliable communication between Intelligent Electronic Devices (IEDs) used for protection of the power network. The messages associated with the GSE services are the Generic Object Oriented Substation Event (GOOSE) messages. The use of GOOSE messages for protection of the electrical system is very important in modern substations. Detailed knowledge of the structure of these messages is important in instances requiring fault diagnosis to determine the cause of mal– operation or to address interoperability concerns or when developing custom IEC 61850- compliant devices with limited functionality. A practical protection application (overcurrent) case study is presented where GOOSE messages are exchanged between a commercial IED and an IEC 61850-compliant controller based on an embedded platform. The basic data model and software development of an actuator node for a circuit breaker is proposed using an IEC 61850 communication stack on an embedded platform. The performance of the GOOSE messages is confirmed to be as per the functional behaviour specified, and per the IEC 68150 standard in terms of the temporal behaviour required. This thesis document tables the methods, software programs, hardware interfacing and system integration techniques that allow for the development and implementation of a low cost IEC 61850-compliant controller unit on an embedded systems platform for the substation automation system. The overcurrent case study distributed between a commercial IED (SIEMENS Siprotec device) and the actuator application developed on an embedded platform for this project (DK60 board) is in compliance with the IEC 61850 standard and utilizing GOOSE messaging is successfully completed both in terms of functional and temporal behaviour. This novel research work contributes not only to the academic community, but to the international Power Systems community as a whole. Keywords: IEC 61850 standard, IEDs, GOOSE message, software modelling, software development, substation automation systems, communication stack, embedded systems, actuator.

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38

Chigwamba, Nyasha. "An investigation into the hardware abstraction layer of the plural node architecture for IEEE 1394 audio devices." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1004841.

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Digital audio network technologies are becoming more prevalent in audio related environments. Yamaha Corporation has created a digital audio network solution, named mLAN (music Local Area Network), that uses IEEE 1394 as its underlying network technology. IEEE 1394 is a digital network technology that is specifically designed for real-time multimedia data transmission. The second generation of mLAN is based on the Plural Node Architecture, where the control of audio and MIDI routings between IEEE 1394 devices is split between two node types, namely an Enabler and a Transporter. The Transporter typically resides in an IEEE 1394 device and is solely responsible for transmission and reception of audio or MIDI data. The Enabler typically resides in a workstation and exposes an abstract representation of audio or MIDI plugs on each Transporter to routing control applications. The Enabler is responsible for configuring audio and MIDI routings between plugs on different Transporters. A Hardware Abstraction Layer (HAL) within the Enabler allows it to uniformly communicate with Transporters that are created by various vendors. A plug-in mechanism is used to provide this capability. When vendors create Transporters, they also create device-specific plug-ins for the Enabler. These plug-ins are created against a Transporter HAL Application Programming Interface (API) that defines methods to access the capabilities of Transporters. An Open Generic Transporter (OGT) guideline document which models all the capabilities of Transporters has been produced. These guidelines make it possible for manufacturers to create Transporters that make use of a common plug-in, although based on different hardware architectures. The introduction of the OGT concept has revealed additional Transporter capabilities that are not incorporated in the existing Transporter HAL API. This has led to the underutilisation of OGT capabilities. The main goals of this investigation have been to improve the Enabler’s plug-in mechanism, and to incorporate the additional capabilities that have been revealed by the OGT into the Transporter HAL API. We propose a new plug-in mechanism, and a new Transporter HAL API that fully utilises both the additional capabilities revealed by the OGT and the capabilities of existing Transporters.

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39

Halton, Christopher H. "An effectiveness study for prioritization algorithms in a communications node model for the Copernicus Tactical Data Information Exchange System (TADIXS)." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 1997. http://handle.dtic.mil/100.2/ADA337403.

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Thesis (M.S. in Systems Technology (Joint Command, Control, and Communications)) Naval Postgraduate School, Sept. 1997.
Thesis advisors, Michael G. Sovereign, Orin E. Marvel. Includes bibliographical references (p. 131). Also available online.

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40

Alam, Muhammad. "Inter layer and cooperative design strategies for green mobile networks." Doctoral thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/12856.

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Doutoramento conjunto MAP-i em Informática
The promise of a truly mobile experience is to have the freedom to roam around anywhere and not be bound to a single location. However, the energy required to keep mobile devices connected to the network over extended periods of time quickly dissipates. In fact, energy is a critical resource in the design of wireless networks since wireless devices are usually powered by batteries. Furthermore, multi-standard mobile devices are allowing users to enjoy higher data rates with ubiquitous connectivity. However, the bene ts gained from multiple interfaces come at a cost in terms of energy consumption having profound e ect on the mobile battery lifetime and standby time. This concern is rea rmed by the fact that battery lifetime is one of the top reasons why consumers are deterred from using advanced multimedia services on their mobile on a frequent basis. In order to secure market penetration for next generation services energy e ciency needs to be placed at the forefront of system design. However, despite recent e orts, energy compliant features in legacy technologies are still in its infancy, and new disruptive architectures coupled with interdisciplinary design approaches are required in order to not only promote the energy gain within a single protocol layer, but to enhance the energy gain from a holistic perspective. A promising approach is cooperative smart systems, that in addition to exploiting context information, are entities that are able to form a coalition and cooperate in order to achieve a common goal. Migrating from this baseline, this thesis investigates how these technology paradigm can be applied towards reducing the energy consumption in mobile networks. In addition, we introduce an additional energy saving dimension by adopting an interlayer design so that protocol layers are designed to work in synergy with the host system, rather than independently, for harnessing energy. In this work, we exploit context information, cooperation and inter-layer design for developing new energy e cient and technology agnostic building blocks for mobile networks. These technology enablers include energy e cient node discovery and short-range cooperation for energy saving in mobile handsets, complemented by energy-aware smart scheduling for promoting energy saving on the network side. Analytical and simulations results were obtained, and veri ed in the lab on a real hardware testbed. Results have shown that up to 50% energy saving could be obtained.
A promessa de uma experiência realmente móvel é de ter a liberdade de deambular por qualquer sítio e não estar preso a um único local. No entanto, a energia requerida para manter dispositivos móveis conectados à rede, num período extenso de tempo, o mesmo rapidamente se dissipa. Na realidade, a energia é um recurso crítico no design de redes sem fios, uma vez que esses dispositivos são alimentados por baterias. Para além disso, dispositivos móveis multi-standard permitem que os utilizadores desfrutem de elevadas taxas de dados com conectividade omnipresente. No entanto, as vantagens adquiridas pelas múltiplas interfaces, imputa uma despesa, sendo essa um consumo maior de energia, numa era onde os dispositivos móveis têm de ser energicamente complacentes. Esta preocupação é reafirmada pelo facto de que a vida da bateria é uma das principais razões que impede os utilizadores de usufruir e utilizar de serviços de multimédia mais avançados nos seus dispositivos, numa base frequente. De forma a assegurar a entrada no mercado para serviços da próxima geração, eficiência energética tem de ser colocada na vanguarda do design de sistemas. No entanto, apesar de esforços recentes, funcionalidades que cumpram os requisitos energéticos em tecnologias "legacy" ainda estão nos seus primórdios e novas abordagens disruptivas são requeridas, juntamente com abordagem de design interdisciplinar, de forma a aproveitar a poupança energética das diversas camadas protocolares. Uma bordagem promissora são os sistemas de cooperação inteligente, que exploram não são contexto da informação, mas também as entidades que são igualmente capazes de formar uma coligação e cooperam de forma a atingir um objectivo comum. Migrar a partir destas referências, esta tese investiga como é que este paradigma tecnológico pode ser aplicado para reduzir a potência e consumo de energia em redes móveis. Para além disso, introduzimos uma dimensão de poupança energética adicional, para adopção de design de camadas intermédias, de forma a que as camadas de protocolos sejam concebidas para trabalhar em sinergia com o sistema anfitrião, ao invés de independentemente, para aproveitamento de energia. Neste trabalho, nós exploramos o contexto da informação, cooperação e design de camadas intermédias para desenvolver blocos de construção energicamente eficientes e tecnologias agnósticas para redes móveis. Estes habilitadores (enablers) tecnológicos incluem um nó de descoberta de energia eficiente e cooperação de curto alcance para poupança energética em aparelhos móveis, complementado com agendamento inteligente, energicamente consciente, de forma a promover a poupança de energia do lado da rede. Analiticamente e simultaneamente, foram obtidos resultados e verificados em laboratório, num modelo de hardware protótipo. Resultados demonstram que pode ser obtido uma poupança energética acima dos 50%.

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41

Zinkhon, David C. "Undersea node localization using node-to-node acoustic ranges in a distributed Seaweb network." Thesis, Monterey, Calif. : Naval Postgraduate School, 2009. http://edocs.nps.edu/npspubs/scholarly/theses/2009/March/09Mar%5FZinkhon.pdf.

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Thesis (M.S. in Engineering Acoustics)--Naval Postgraduate School, March 2009.
Thesis Advisor(s): Rice, Joseph A. "March 2009." Description based on title screen as viewed on April 24, 2009. Author(s) subject terms: Underwater acoustics, Seaweb, Localization, Difference linearization. Includes bibliographical references (p. 97-98). Also available in print.

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42

Kosar, Onur. "Query Based Energy Efficient Clustering Methods For Wireless Sensor Networks." Master's thesis, METU, 2011. http://etd.lib.metu.edu.tr/upload/12613516/index.pdf.

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In Wireless Sensor Networks, designing a low overhead routing protocol is crucial for prolonging network lifetime. Wireless sensor nodes depend on limited batteries and if they run out of battery, they cannot contribute to the sensing. There are lots of studies aimed at prolonging network lifetime. One of the methods to extend life time of the wireless sensor networks is clustering. In clustering approaches main aim is to prevent unnecessary messaging and decrease number of messages exchanged by aggregating messages. Clustering also contributes to prolong network life time by ruling the child node communications and therefore it decreases message loss caused by transmission collisions. Cluster heads in clusters schedule nodes for sending and receiving messages. In this thesis, a clustering approach based on queries disseminated by sinks is proposed. Two methods to prolong lifetime of sensor network by forming appropriate clusters and selecting suitable cluster heads is developed. Performance of the proposed methods is also evaluated with computer simulations.

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43

Gebreyohannes, Fikre Tsigabu. "Design of Ultra-Low Power Wake-Up Receiver in 130nm CMOS Technology." Thesis, Linköpings universitet, Elektroniksystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-78797.

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Wireless Sensor Networks have found diverse applications from health to agriculture and industry. They have a potential to profound social changes, however, there are also some challenges that have to be addressed. One of the problems is the limited power source available to energize a sensor node. Longevity of a node is tied to its low power design. One of the areas where great power savings could be made is in nodal communication. Different schemes have been proposed targeting low power communication and short network latency. One of them is the introduction of ultra-low power wake-up receiver for monitoring the channel. Although it is a recent proposal, there has been many works published. In this thesis work, the focus is study and comparison of architectures for a wake-up receiver. As part of this study, an envelope detector based wake-up receiver is designed in 130nm CMOS Technology. It has been implemented in schematic and layout levels. It operates in the 2.4GHz ISM band and consumes a power consumption of 69µA at 1.2V supply voltage. A sensitivity of -52dBm is simulated while receiving 100kb/s OOK modulated wake-up signals.
This is a master's thesis work by a communication electronics student in a German company called IMST GmbH.

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44

Alnas, Mohamed J. R. "Using Link Layer Information to Enhance Mobile IP Handover Mechanism. An investigation in to the design, analysis and performance evaluation of the enhanced Mobile IP handover mechanism using link layer information schemes in the IP environment." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4900.

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Mobile computing is becoming increasingly important, due to the rise in the number of portable computers and the desire to have continuous network connectivity to the Internet, irrespective of the physical location of the node. We have also seen a steady growth of the market for wireless communication devices. Such devices can only have the effect of increasing the options for making connections to the global Internet. The Internet infrastructure is built on top of a collection of protocols called the TCP/IP protocol suite. Transmission Control Protocol (TCP) and Internet Protocol (IP) are the core protocols in this suite. There are currently two standards: one to support the current IPv4 and one for the upcoming IPv6 [1]. IP requires the location of any node connected to the Internet to be uniquely identified by an assigned IP address. This raises one of the most important issues in mobility because, when a node moves to another physical location, it has to change its IP address. However, the higher-level protocols require the IP address of a node to be fixed for identifying connections. The Mobile Internet Protocol (Mobile IP) is an extension to the Internet Protocol proposed by the Internet Engineering Task Force (IETF) that addresses this issue. It enables mobile devices to stay connected to the Internet regardless of their locations, without changing their IP addresses and, therefore, an ongoing IP session will not be interrupted [2, 3, 4]. More precisely, Mobile IP is a standard protocol that builds on the Internet Protocol by making mobility transparent to applications and higher-level protocols like TCP. However, before Mobile IP can be broadly deployed, there are still several technical barriers, such as long handover periods and packet loss that have to be overcome, in addition to other technical obstacles, including handover performance, security issues and routing efficiency [7]. This study presents an investigation into developing new handover mechanisms based on link layer information in Mobile IP and fast handover in Mobile IPv6 environments. The main goal of the developed mechanisms is to improve the overall IP mobility performance by reducing packet loss, minimizing signalling overheads and reducing the handover processing time. These models include the development of a cross-layer handover scheme using link layer information and Mobile Node (MN) location information to improve the performance of the communication system by reducing transmission delay, packet loss and registration signalling overheads. Finally, the new schemes are developed, tested and validated through a set of experiments to demonstrate the relative merits and capabilities of these schemes.

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45

Alnas, Mohamed Jimaa Ramadan. "Using link layer information to enhance mobile IP handover mechanism : an investigation into the design, analysis and performance evaluation of the enhanced mobile IP handover mechanism using link layer information schemes in the IP environment." Thesis, University of Bradford, 2010. http://hdl.handle.net/10454/4900.

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Mobile computing is becoming increasingly important, due to the rise in the number of portable computers and the desire to have continuous network connectivity to the Internet, irrespective of the physical location of the node. We have also seen a steady growth of the market for wireless communication devices. Such devices can only have the effect of increasing the options for making connections to the global Internet. The Internet infrastructure is built on top of a collection of protocols called the TCP/IP protocol suite. Transmission Control Protocol (TCP) and Internet Protocol (IP) are the core protocols in this suite. There are currently two standards: one to support the current IPv4 and one for the upcoming IPv6 [1]. IP requires the location of any node connected to the Internet to be uniquely identified by an assigned IP address. This raises one of the most important issues in mobility because, when a node moves to another physical location, it has to change its IP address. However, the higher-level protocols require the IP address of a node to be fixed for identifying connections. The Mobile Internet Protocol (Mobile IP) is an extension to the Internet Protocol proposed by the Internet Engineering Task Force (IETF) that addresses this issue. It enables mobile devices to stay connected to the Internet regardless of their locations, without changing their IP addresses and, therefore, an ongoing IP session will not be interrupted [2, 3, 4]. More precisely, Mobile IP is a standard protocol that builds on the Internet Protocol by making mobility transparent to applications and higher-level protocols like TCP. However, before Mobile IP can be broadly deployed, there are still several technical barriers, such as long handover periods and packet loss that have to be overcome, in addition to other technical obstacles, including handover performance, security issues and routing efficiency [7]. This study presents an investigation into developing new handover mechanisms based on link layer information in Mobile IP and fast handover in Mobile IPv6 environments. The main goal of the developed mechanisms is to improve the overall IP mobility performance by reducing packet loss, minimizing signalling overheads and reducing the handover processing time. These models include the development of a cross-layer handover scheme using link layer information and Mobile Node (MN) location information to improve the performance of the communication system by reducing transmission delay, packet loss and registration signalling overheads. Finally, the new schemes are developed, tested and validated through a set of experiments to demonstrate the relative merits and capabilities of these schemes.

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Sandström, Krantz Alexander. "Node hardening verification." Thesis, Linköping University, Department of Electrical Engineering, 2008. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-11822.

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Secure networks require each node to individually be as secure as possible. Transporting telecommunication data using IP based networks increases the need for security solutions due to increased exposure to threats. Ericsson currently provides a reference solution for carrying radio traffic over standardized Ethernet using IP, which in the current version relies on third party equipment. This equipment, and their recommended configuration, needs to be tested to ensure that the reference solution is as secure as possible.

The main purpose of this thesis is to provide Ericsson with a template that describes how security testing of the currently recommended equipment can be carried out.

För att ett nätverk skall vara säkert krävs att dess noder är invidivuellt säkrade. Transportering av telekommunikation över IP baserade nätverk ökar behovet av säkerhetslösningar då det ökar riskerna. Ericsson erbjuder idag en referenslösning för transport av telekommunikationstrafik över IP nätverk, som i dagsläget använder tredje-parts-utrustning. Denna utrustning och den konfiguration som rekommenderas i referenslösningen behöver säkerhetstestas för att säkerställa att den erbjudna lösningen håller en hög säkerhetsnivå.

Huvudsyftet med detta exjobb är att ta fram en praktisk metod som kan användas vid Ericsson för att säkerhetstesta den utrustning som i dagsläget rekommenderas i referenslösningen.

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Radovic, Zoran. "Software Techniques for Distributed Shared Memory." Doctoral thesis, Uppsala University, Department of Information Technology, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-6058.

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In large multiprocessors, the access to shared memory is often nonuniform, and may vary as much as ten times for some distributed shared-memory architectures (DSMs). This dissertation identifies another important nonuniform property of DSM systems: nonuniform communication architecture, NUCA. High-end hardware-coherent machines built from large nodes, or from chip multiprocessors, are typical NUCA systems, since they have a lower penalty for reading recently written data from a neighbor's cache than from a remote cache. This dissertation identifies node affinity as an important property for scalable general-purpose locks. Several software-based hierarchical lock implementations exploiting NUCAs are presented and evaluated. NUCA-aware locks are shown to be almost twice as efficient for contended critical sections compared to traditional lock implementations.

The shared-memory “illusion”' provided by some large DSM systems may be implemented using either hardware, software or a combination thereof. A software-based implementation can enable cheap cluster hardware to be used, but typically suffers from poor and unpredictable performance characteristics.

This dissertation advocates a new software-hardware trade-off design point based on a new combination of techniques. The two low-level techniques, fine-grain deterministic coherence and synchronous protocol execution, as well as profile-guided protocol flexibility, are evaluated in isolation as well as in a combined setting using all-software implementations. Finally, a minimum of hardware trap support is suggested to further improve the performance of coherence protocols across cluster nodes. It is shown that all these techniques combined could result in a fairly stable performance on par with hardware-based coherence.

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Liu, Jie. "Structural organization and molecular phenotype of mouse sinotrial node and atrioventricular node." Thesis, University of Oxford, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.424731.

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Shubitz, Lisa. "Coccidioides Lymph Node Histopathology." The University of Arizona, 2016. http://hdl.handle.net/10150/620043.

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Lian, Keng Jin. "Adaptive Antenna Arrays for Satellite Personal Communication Systems." Thesis, Virginia Tech, 1997. http://hdl.handle.net/10919/36949.

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Since about the turn of the decade, several proposals have come forth for personal communication services implemented by means of multiple satellite systems. These satellite systems are similar to current terrestrial cellular technologies, which are still relatively new and have numerous technical problems associated with them. As a result, these satellite systems will also experience some of the similar problems. Two of such problems are the issue of multipath and interference. These problems may result in significant link degradation and affect overall capacity. To overcome this problem, adaptive antenna arrays on handheld terminals are proposed. This technique is believed to be better than omni-directional antennas which radiate in all directions. Adaptive antenna arrays have the ability to adapt to the changing environment and null out the interference. The LMS algorithm was investigated and used in the simulation of the adaptive array. The performance of the LMS array was discussed in detail. In the case of a multipath, an alternate approach was proposed where a diversity combiner is used to phase shift the multipath and combine the Signal of Interest and multipaths constructively.
Master of Science

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Dissertations / Theses on the topic 'Node to Node Communication'

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