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Song, Ji‐Won. "Understanding user interaction problems with wireless connection via research through design." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/10890.
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People frequently have problems making multiple devices work together. In this thesis, I use the Research‐through‐Design approach to understand the issues and propose solutions. Through an iterative series of investigations, the problems people have with the connection of multiple devices has been examined, including usability issues, difficulties with the sequential connection procedure, and difficulties performing an action. I found non‐expert users to have difficulties with interpreting and evaluating the devices’ interaction status regarding the sequence of the connection procedure. When an evaluation problem occurs, they have problems dealing with the required sequence or diagnosing the error in their interactions. The problem understanding was examined from additional cases. The comprehension of the problems allowed me to generate design implications and propose a design solution. I proposed two implications with which to solve the stated problem. I suggested helping users evaluate device interaction and reduce unnecessary user interactions. A design framework was suggested as a solution by providing diagrammatic representations of system interaction and signals revealing device status. I then assessed the suggested solutions using paper prototypes, and demonstrated their effectiveness. The improved interfaces helped users evaluate device connection status so they may determine how to proceed with sequential interaction. With the Research‐through‐Design approach constructing knowledge by integrating theories and hypothesis, I found the feature of user‐multiple device interaction in which a user is required to manage the interaction between the devices. A single device cannot aid the user interaction. In the dissertation, I proposed a desirable state of user interaction, which is achieved by two devices revealing connection states together so that a user can earn a useful system image.
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Fabbri, Luca. "Computing primal solutions with exact arithmetics in SCIP." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amslaurea.unibo.it/8541/.
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The research for exact solutions of mixed integer problems is an active topic
in the scientific community. State-of-the-art MIP solvers exploit a floating-
point numerical representation, therefore introducing small approximations.
Although such MIP solvers yield reliable results for the majority of problems,
there are cases in which a higher accuracy is required. Indeed, it is known
that for some applications floating-point solvers provide falsely feasible
solutions, i.e. solutions marked as feasible because of approximations that
would not pass a check with exact arithmetic and cannot be practically
implemented.
The framework of the current dissertation is SCIP, a mixed integer
programs solver mainly developed at Zuse Institute Berlin. In the same site
we considered a new approach for exactly solving MIPs. Specifically, we
developed a constraint handler to plug into SCIP, with the aim to analyze
the accuracy of provided floating-point solutions and compute exact primal solutions starting from floating-point ones.
We conducted a few computational experiments to test the exact primal
constraint handler through the adoption of two main settings. Analysis
mode allowed to collect statistics about current SCIP solutions' reliability.
Our results confirm that floating-point solutions are accurate enough with
respect to many instances. However, our analysis highlighted the presence of
numerical errors of variable entity. By using the enforce mode, our constraint
handler is able to suggest exact solutions starting from the integer part of
a floating-point solution. With the latter setting, results show a general
improvement of the quality of provided final solutions, without a significant loss of performances.
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Jiang, Canming. "Some Optimization Problems in Wireless Networks." Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77120.
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Recently, many new types of wireless networks have emerged for both civil and military applications, such as cognitive radio networks, MIMO networks. There is a strong interest in exploring the optimal performance of these new emerging networks, e.g., maximizing the network throughput, minimizing network energy consumption. Exploring the optimal performance objectives of these new types of wireless networks is both important and intellectual challenging. On one hand, it is important for a network researcher to understand the performance limits of these new wireless networks. Such performance limits are important not only for theoretical understanding, but also in that they can be used as benchmarks for the design of distributed algorithms and protocols. On the other hand, due to some unique characteristics associated with these networks, existing analytic techniques may not be applied directly to obtain the optimal performance. As a result, new theoretical results, along with new mathematical tools, need to be developed.
The goal of this dissertation is to make a fundamental advance on network performance optimization via exploring a series of optimization problems. Based on the scale of the underlying wireless network, the works in this dissertation are divided into two parts. In the first part, we study the asymptotic capacity scaling laws of different types of wireless networks. By "asymptotic", we mean that the number of nodes in the network goes to infinity. Such asymptotic capacity scaling laws offer fundamental understandings on the trend of maximum user throughput behavior when the network size increases. In the second part of this dissertation, we study several optimization problems of finite-sized wireless networks. Under a given network size, we accurately characterize some performance limits (e.g., throughput, energy consumption) of wireless networks and provide solutions on how to achieve the optimal objectives. The main contributions of this dissertation can be summarized as follows, where the first three problems are on asymptotic capacity scaling laws and the last three problems are optimization problems of finite-sized wireless networks.
1. Capacity Scaling Laws of Cognitive Radio Ad Hoc Networks. We first study the capacity scaling laws for cognitive radio ad hoc networks (CRNs), i.e., how each individual node's maximum throughput scales as the number of nodes in the network increases. This effort is critical to the fundamental understanding of the scalability of such network. However, due to the heterogeneity in available frequency bands at each node, the asymptotic capacity is much more difficult to develop than prior efforts for other types of wireless networks. To overcome this difficulty, we introduce two auxiliary networks ζ and α to analyze the capacity upper and lower bounds. We derive the capacity results under both the protocol model and the physical model. Further, we show that the seminal results developed by Gupta and Kumar for the simple single-channel single-radio (SC-SR) networks are special cases under the results for CRNs.
2. Asymptotic Capacity of Multi-hop MIMO Ad Hoc Networks. Multi-input multi-output (MIMO) is a key technology to increase the capacity of wireless networks. Although there has been extensive work on MIMO at the physical and link layers, there has been limited work on MIMO at the network layer (i.e., multi-hop MIMO ad hoc network), particularly results on capacity scaling laws. In this work, we investigate capacity scaling laws for MIMO ad hoc networks. Our goal is to find the achievable throughput of each node as the number of nodes in the network increases. We employ a MIMO network model that captures spatial multiplexing (SM) and interference cancellation (IC). We show that for a MIMO network with n randomly located nodes, each equipped with γ antennas and a rate of W on each data stream, the achievable throughput of each node is Θ(γW/√ n ln n).
3. Toward Simple Criteria for Establishing Capacity Scaling Laws. Capacity scaling laws offer fundamental understanding on the trend of user throughput behavior when the network size increases. Since the seminal work of Gupta and Kumar, there have been tremendous efforts developing capacity scaling laws for ad hoc networks with various advanced physical layer technologies. These efforts led to different custom-designed approaches, most of which were intellectually challenging and lacked universal properties that can be extended to address scaling laws of ad hoc networks with a different physical layer technology. In this work, we present a set of simple yet powerful general criteria that one can apply to quickly determine the capacity scaling laws for various physical layer technologies under the protocol model. We prove the correctness of our proposed criteria and validate them through a number of case studies, such as ad hoc networks with directional antenna, MIMO, cognitive radio, multi-channel and multi-radio, and multiple packet reception. These simple criteria will serve as powerful tools to networking researchers to obtain throughput scaling laws of ad hoc networks under different physical layer technologies, particularly those to appear in the future.
4. Exploiting SIC forMulti-hopWireless Networks. There is a growing interest on exploiting interference (rather than avoiding it) to increase network throughput. In particular, the so-called successive interference cancellation (SIC) scheme appears very promising, due to its ability to enable concurrent receptions from multiple transmitters and interference rejection. However, due to some stringent constraints and limit, SIC alone is inadequate to handle all concurrent interference. We advocate a joint interference exploitation and avoidance approach, which combines the best of interference exploitation and interference avoidance, while avoiding each's pitfalls. We discuss the new challenges of such a new approach in a multi-hop wireless network and propose a formal optimization framework, with cross-layer formulation of physical, link, and network layers. This framework offers a rather complete design space for SIC to squeeze the most out of interference. The goal of this effort is to lay a mathematical foundation for modeling and analysis of a joint interference exploitation and avoidance scheme in a multi-hop wireless network. Through modeling and analysis, we develop a tractable model that is suitable for studying a broad class of network throughput optimization problems. To demonstrate the practical utility of our model, we conduct a case study. Our numerical results affirm the validity of our model and give insights on how SIC can optimally interact with an interference avoidance scheme.
5. Throughput Optimization with Network-wide Energy Constraint. Conserving network wide energy consumption is becoming an increasingly important concern for network operators. In this work, we study network-wide energy conservation problem which we hope will offer insights to both network operators and users. Specifically, we study how to maximize network throughput under a network-wide energy constraint for a general multi-hop wireless network. We formulate this problem as a mixed-integer nonlinear program (MINLP). We propose a novel piece-wise linear approximation to transform the nonlinear constraints into linear constraints. We prove that the solution developed under this approach is near optimal with guaranteed performance bound.
6. Bicriteria Optimization in Multi-hop Wireless Networks. Network throughput and energy consumption are two important performance metrics for a multi-hop wireless network. Current state-of-the-art is limited to either maximizing throughput under some energy constraint or minimizing energy consumption while satisfying some throughput requirement. However, the important problem of how to optimize both objectives simultaneously remains open. In this work, we take a multicriteria optimization approach to offer a systematic study on the relationship between the two performance objectives. We show that the solution to the multicriteria optimization problem characterizes the envelope of the entire throughput energy region, i.e., the so-called optimal throughput-energy curve. We prove some important properties of the optimal throughput-energy curve. For case study, we consider both linear and nonlinear throughput functions. For the linear case, we characterize the optimal throughput-energy curve precisely through parametric analysis, while for the nonlinear case, we use a piece-wise linear approximation to approximate the optimal throughput-energy curve with arbitrary accuracy. Our results offer important insights on exploiting the trade-off between the two performance metrics.Ph. D.
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Chen, Lijun Doyle John Comstock. "Wireless network design and control /." Diss., Pasadena, Calif. : California Institute of Technology, 2007. http://resolver.caltech.edu/CaltechETD:etd-12282006-181735.
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Balakrishnan, Anantaram, Thomas L. Magnanti, and Prakash Mirchandani. "The Multi-Network Design Problem." Massachusetts Institute of Technology, Operations Research Center, 1991. http://hdl.handle.net/1721.1/5200.
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This paper studies a new multi-facility network synthesis problem, called the Multi-level Network Design (MLND) problem, that arises in the topological design of hierarchical communication, transportation, and electric power distribution networks whose nodes have varying levels of importance:the more critical or higher level nodes require higher grade interconnections. Given an undirected network with L possible facility types for each edge, and a partition of the nodes into L levels, the MLND problem seeks a connected design that minimizes total fixed cost while spanning all the nodes, and connecting nodes at each level via facilities of the corresponding or higher type. This problem generalizes the well-known Steiner network problem and the hierarchical network design problem. In this paper, we describe alternative model formulations for this problem and analyze the worst-case performance for heuristics based upon Steiner and spanning tree computations. For one model that we consider, the heuristic worst-case bounds on the performance ratio are either 4/3 or the worst-case performance ratio p of the embedded Steiner tree heuristic. A companion paper develops and tests a dual ascent procedure that generates tight upper and lower bounds on the optimal value of the problem. Keywords: Network design, integer programming, valid inequalities, worstcase analysis of heuristics.
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Mukhija, Punit. "A Wireless Call Button Network Design." Thesis, Virginia Tech, 1999. http://hdl.handle.net/10919/9763.
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Traditional call button networks that control elevator systems utilize a wired connection for communication. The communication cables are run through the elevator shaft from one call button to another and finally to the controller on the roof. Installing this wired link is highly time consuming. In this thesis, we propose the design for a wireless call button network. Two important features of this wireless network design are low cost and low power consumption. Controller Area Network (CAN) is a widely used protocol for wired networks and has been proposed for use in next generation elevator control systems. A modified CAN for wireless (MCANW) protocol has been developed for the wireless call button network. The wireless link will be implemented via the use of data radios. A modified form of traditional Binary Phase Shift Keying (BPSK) modulation scheme for the radios is proposed. The proposed modulation scheme, like differential BPSK, can be detected non-coherently but it offers better performance than differential BPSK. Its implementation includes an innovative tracking algorithm to maintain synchronization at the receiver.Master of Science
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Oh, Khoon Wee. "Wireless network security : design considerations for an enterprise network /." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2004. http://library.nps.navy.mil/uhtbin/hyperion/04Dec%5FOh.pdf.
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Joyner, Valencia Margie. "Integrated circuit design for wireless network receivers." Thesis, University of Cambridge, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.619998.
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Samsudin, Rina Juliawati. "Integrated circuit design for wireless network transmitters." Thesis, University of Cambridge, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.615711.
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Flores, Luyo Luis Ernesto. "Vehicle Routing Problem for the Collection of Information in Wireless Network." Thesis, Avignon, 2018. http://www.theses.fr/2018AVIG0230/document.
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Les progrès dans l'architecture de réseau informatique ajoutent continuellement de nouvelles fonctionnalités aux problèmes de routage des véhicules. Dans cette thèse, le problème de tournée des véhicules avec la collecte de donnée sans fil (WT-VRP) est étudié. Il recherche un itinéraire pour le véhicule chargé de collecter des informations auprès des stations ainsi qu'un planning efficace de collecte d'informations. La nouvelle fonctionnalité ajoutée ici est la possibilité de récupérer des informations via une transmission sans fil, sans visiter physiquement les stations du réseau. Le WT-VRP a des applications dans la surveillance sous-marine et la surveillance environnementale. Nous discutons les critères pour mesurer l'efficacité d'une solution et proposons des formulations de programmation linéaire en nombre entier mixte pour résoudre le problème. Des expériences computationnelles ont été réalisées pour accéder à la complexité numérique du problème et pour comparer les solutions selon les critères proposés. Ensuite, nous avons renforcé certains modèles ainsi que considéré différentes suppositions pour le réseaux sans fils. Finalement, pour être capable de résoudre le problème dans des réseaux de grande échelle, nous avons développés des méthodes heuristiques pour le WT-VRPThe vehicle routing problem is one of the most studied problems in Operations Research.Different variants have been treated in the past 50 years and with technologicaladvances, new challenges appear. In this thesis, we introduce a new variation of theVRP appearing in wireless networks. The new characteristic added to this well-knowproblem is the possibility of pick-up information via wireless transmissions. In the contextconsidered here, a unique base station is connected with the outside and a vehicleis responsible for collecting information via wireless connection to the vehicle when it islocated in another sufficiently close station. Simultaneous transmissions are permitted.Time of transmission depends on the distance between stations, the amount of informationtransmitted, and other physical factors (e.g obstacles along the way, installedequipment). Information to be sent outside of the network is continuously generatedin each station at a constant rate. The first contribution of this thesis is the introductionof a mixed ILP formulation for a variation in which it is only possible to send all theinformation or nothing during a wireless transmission. For this model three differentstrategies are investigated: maximizing total amount of information extracted an theend of the time horizon; maximizing the average of the information in the vehicle ateach time point; and maximizing the satisfaction of each station at the end of the timehorizon. Each strategy is translated as a different objective function for the mixed ILPformulation. The problem is then reformulated by accepting the option of sending onlypart of the information during a wireless transmission and considering only the firststrategy,(i.e. maximizing the amount of information extracted at the end of the horizontime). For this new version, we present three mixed ILP formulations, each one withadvantages and disadvantages. These mixed ILP models are compared according to theCPU time, amount of information collected, gap of unresolved instances, etc. Becausein real life we need to solve problems with a large number of stations, in this thesis,we also propose heuristics methods for the second version of the problem introduced.We build some heuristics that do not depend on the mixed ILP model (as for exampleGreedy heuristics) and also matheuristcs. In our matheuristics our best model (a vehicleevent model) is used as a base for the development of construction of Heuristics aswell as local search heuristics
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Sexton, Niall Jason. "The design of a multimedia wireless access network." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp05/mq20882.pdf.
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Yuan, Fenghua. "Lightweight network management design for wireless sensor networks." Online access for everyone, 2007. http://www.dissertations.wsu.edu/Thesis/Fall2007/F_Yuan_081307.pdf.
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Chen, J. "Model-Based Wireless Network Control using Co-Design." Thesis, Queen's University Belfast, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.527670.
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Saeed, Bahghtar Ibraheem. "Design of a wireless intelligent fuzzy controller network." Thesis, University of Huddersfield, 2014. http://eprints.hud.ac.uk/id/eprint/24569/.
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Since the first application of fuzzy logic in the field of control engineering, fuzzy logic control has been successfully employed in controlling a wide variety of applications, such as commercial appliances, industrial automation, robots, traffic control, cement kilns and automotive engineering. The human knowledge on controlling complex and non-linear processes can be incorporated into a controller in the form of linguistic expressions. Despite these achievements, however, there is still a lack of an empirical or analytical design study which adequately addresses a systematic auto-tuning method. Indeed, tuning is one of the most crucial parts in the overall design of fuzzy logic controllers and it has become an active research field. Various techniques have been utilised to develop algorithms to fine-tune the controller parameters from a trial and error method to very advanced optimisation techniques. The structure of fuzzy logic controllers is not straightforward as is the case in PID controllers. In addition, there is also a set of parameters that can be adjusted, and it is not always easy to find the relationship between the parameters and the controller performance measures. Moreover, in general, controllers have a wide range of setpoints; changing from one value to another requiring the controller parameters to be re-tuned in order to maintain a satisfactory performance over the entire range of setpoints. This thesis deals with the design and implementation of a new intelligent algorithm for fuzzy logic controllers in a wireless network structure. The algorithm enables the controllers to learn about their plants and systematically tune their gains. The algorithm also provides the capability of retaining the knowledge acquired during the tuning process. Furthermore, this knowledge is shared on the network through a wireless communication link with other controllers. Based on the relationships between controller gains and the closed-loop characteristics, an auto-tuning algorithm is developed. Simulation experiments using standard second order systems demonstrate the effectiveness of the algorithm with respect to auto-tuning, tracking setpoints and rejecting external disturbances. Furthermore, a zero overshoot response is produced with improvements in the transient and the steady state responses. The wireless network structure is implemented using LabVIEW by composing a network of several fuzzy controllers. The results demonstrate that the controllers are able to retain and share the knowledge.
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Fréchette, Alexandre. "Hub routing for the robust network design problem." Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=114431.
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Robust network design (RND) applies the concept of robustness from optimization with uncertainty to the area of network design. Primary motivations stem from applications in telecommunication networks. The main presupposition is that demands across the networks are variable or unpredictable. They originate from a predefined demand set, called a demand universe. Moreover, practical impediments of network design enforce the routing of the demands to be oblivious, or fixed in advance, and to not depend on a particular instantiation from the demand universe. Additional restrictions, referred to as a routing model, are often enforced on the routing's structure. Shortest paths (SP) and hub (HUB) routing models have received particular attention, both on the theoretical and practical level. In this work, we introduce a new routing model, called the hierarchical hub routing model (HH), as a generalization to HUB. We study the theoretical properties of RND restricted to HH (RNDHH). Namely, we show its APX-hardness and provide a O(log n)-approximation algorithm. We then show how RNDHH is tractable when the problem is constrained to a particular demand universe based on demands routable on a tree. We also compare the costs of optimal solutions to RND using HH and other important oblivious routing models. Finally, we leverage HH in a practical study of a new demand universe called the capped hose model, which is a blend of the hose and the pipe model, two widely used demand universes. We use the capped hose model to shed light on which demand universes favour more a SP-like as opposed to a HH-like routing. To do so, we develop a heuristic algorithm for RNDHH, and benchmark our approach against SP using representative carrier networks and a variety of capped hose demands, parametrized by their similitude to a hose or pipe model. This study reveals conditions under which multi-hub routings, that is HH, gives improvements over single-hub and shortest path routings.Le design de réseaux robustes (RND) est celui qui applique le concept de robustesse, issu de l'optimisation avec incertitude, au domaine de la conception de réseaux. Les principales motivations derrière cette application découlent de demandes provenant des réseaux de télécommunication. La prémisse principale est que les demandes à travers les réseaux sont variables ou imprévisibles. Toutefois, nous savons que ces demandes proviennent d'un ensemble prédéfini appelé univers de demandes. De plus, des contraintes pratiques du design de réseaux requiert que le routage des demandes soit inconscient, ou fixé d'avance, et qu'il ne dépende pas d'une instanciation particulière de l'univers de demandes. Des contraintes additionnelles, connues sous le nom de modèle de routage, s'appliquent souvent à la structure du routage. Les routages par chemins les plus courts (SP) et par moyeu unique (HUB) ont reçu une attention importante, tant au niveau théorique que pratique. Dans cette thèse, nous introduisons un nouveau modèle de routage appelé routage hiérarchique par moyeux (HH), qui est une généralisation de HUB. Nous étudions les propriétés théoriques de RND restreint à HH (RNDHH). Plus particulièrement, nous démontrons son caractère APX-difficile et fournissons un algorithme O(log n)-approché. Par la suite, nous montrons comment RNDHH devient facilement soluble lorsque restreint à un univers de demandes particulier, basé sur des demandes qui peuvent être routées sur un arbre donné. Nous comparons également le coût des solutions optimales lorsque RND utilise HH ainsi que d'autres modèles de routage inconscients importants. Finalement, nous exploitons HH dans une étude pratique sur un nouvel univers de demandes, appelé modèle par tuyaux restreints, qui est un mélange de deux univers de demandes largement utilisés soit le modèle par tuyaux et le modèle par conduits. Nous utilisons le modèle par tuyaux restreints pour caractériser quel univers de demandes favorise un routage similaire à SP contrairement à un routage HH. Pour ce faire, nous développons un algorithme heuristique pour RNDHH et évaluons notre approche par rapport à SP à l'aide de réseaux d'opérateur ainsi que plusieurs types de demandes du modèle par tuyaux restreints, ceux-ci ayant été paramétrés par leur similitude à un modèle par tuyaux ou un modèle par conduits. Cette étude révèle les conditions à travers lesquelles le routage par multiples moyeux, c'est-à-dire HH, surpasse celui par HUB et SP.
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Park, Pangun. "Modeling, Analysis and Design of Wireless Sensor Network Protocols." Doctoral thesis, KTH, Reglerteknik, 2011. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-29821.
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Wireless sensor networks (WSNs) have a tremendous potential to improve the efficiencyof many systems, for instance, in building automation and process control.Unfortunately, the current technology does not offer guaranteed energy efficiencyand reliability for closed-loop stability. The main contribution of this thesis is toprovide a modeling, analysis, and design framework for WSN protocols used in controlapplications. The protocols are designed to minimize the energy consumption ofthe network, while meeting reliability and delay requirements from the applicationlayer. The design relies on the analytical modeling of the protocol behavior.First, modeling of the slotted random access scheme of the IEEE 802.15.4medium access control (MAC) is investigated. For this protocol, which is commonlyemployed in WSN applications, a Markov chain model is used to derive theanalytical expressions of reliability, delay, and energy consumption. By using thismodel, an adaptive IEEE 802.15.4 MAC protocol is proposed. The protocol designis based on a constrained optimization problem where the objective function is theenergy consumption of the network, subject to constraints on reliability and packetdelay. The protocol is implemented and experimentally evaluated on a test-bed. Experimentalresults show that the proposed algorithm satisfies reliability and delayrequirements while ensuring a longer lifetime of the network under both stationaryand transient network conditions.Second, modeling and analysis of a hybrid IEEE 802.15.4 MAC combining theadvantages of a random access with contention with a time division multiple access(TDMA) without contention are presented. A Markov chain is used to model thestochastic behavior of random access and the deterministic behavior of TDMA.The model is validated by both theoretical analysis and Monte Carlo simulations.Using this new model, the network performance in terms of reliability, averagepacket delay, average queueing delay, and throughput is evaluated. It is shown thatthe probability density function of the number of received packets per superframefollows a Poisson distribution. Furthermore, it is determined under which conditionsthe time slot allocation mechanism of the IEEE 802.15.4 MAC is stable.Third, a new protocol for control applications, denoted Breath, is proposedwhere sensor nodes transmit information via multi-hop routing to a sink node. Theprotocol is based on the modeling of randomized routing, MAC, and duty-cycling.Analytical and experimental results show that Breath meets reliability and delayrequirements while exhibiting a nearly uniform distribution of the work load. TheBreath protocol has been implemented and experimentally evaluated on a test-bed.Finally, it is shown how the proposed WSN protocols can be used in controlapplications. A co-design between communication and control application layers isstudied by considering a constrained optimization problem, for which the objectivefunction is the energy consumption of the network and the constraints are thereliability and delay derived from the control cost. It is shown that the optimaltraffic load when either the communication throughput or control cost are optimizedis similar.QC 20110217
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Larish, Bryan. "An information theory approach to wireless sensor network design." Diss., Georgia Institute of Technology, 2012. http://hdl.handle.net/1853/47725.
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We use tools and techniques from information theory to improve the design of Wireless Sensor Networks (WSNs). We do this by first developing a model for WSNs that is analogous to models of communication systems in information theory. In particular, we define the notion of WSN Coding, which is analogous to source coding from information theory, and the Collection Channel, which is analogous to a transport channel in information theory. We then use source coding theorems from information theory to develop three results that aid in WSN design. First, we propose a new top-level design metric for WSNs. Second, we develop an efficiency measure for the sensing process in a WSN. Finally, we use techniques from source coding schemes to suggest new designs for WSNs and the sensors they contain. We strive for tools that apply under the most general conditions possible so that designers can use them in any WSN. However, we also apply each tool to a specific example WSN illustrate the tool's value.
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Fan, Jin. "Using genetic algorithms to optimise wireless sensor network design." Thesis, Loughborough University, 2009. https://dspace.lboro.ac.uk/2134/6312.
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Wireless Sensor Networks(WSNs) have gained a lot of attention because of their potential to immerse deeper into people' lives. The applications of WSNs range from small home environment networks to large habitat monitoring. These highly diverse scenarios impose different requirements on WSNs and lead to distinct design and implementation decisions. This thesis presents an optimization framework for WSN design which selects a proper set of protocols and number of nodes before a practical network deployment. A Genetic Algorithm(GA)-based Sensor Network Design Tool(SNDT) is proposed in this work for wireless sensor network design in terms of performance, considering application-specific requirements, deployment constrains and energy characteristics. SNDT relies on offine simulation analysis to help resolve design decisions. A GA is used as the optimization tool of the proposed system and an appropriate fitness function is derived to incorporate many aspects of network performance. The configuration attributes optimized by SNDT comprise the communication protocol selection and the number of nodes deployed in a fixed area. Three specific cases : a periodic-measuring application, an event detection type of application and a tracking-based application are considered to demonstrate and assess how the proposed framework performs. Considering the initial requirements of each case, the solutions provided by SNDT were proven to be favourable in terms of energy consumption, end-to-end delay and loss. The user-defined application requirements were successfully achieved.
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Shekhar, Hemabh. "Multi-antenna physical layer models for wireless network design." Diss., Atlanta, Ga. : Georgia Institute of Technology, 2008. http://hdl.handle.net/1853/22681.
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Thesis (Ph. D.)--Electrical and Computer Engineering, Georgia Institute of Technology, 2008.Committee Chair: Ingram, Mary Ann; Committee Member: Andrew, Alfred; Committee Member: Copeland, John; Committee Member: Owen, Henry; Committee Member: Sivakumar, Raghupathy.
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Quek, Tony Q. S. (Tony Quee Seng). "Efficient approaches to robust and cooperative wireless network design." Thesis, Massachusetts Institute of Technology, 2008. http://hdl.handle.net/1721.1/42908.
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Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2008.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Includes bibliographical references (p. 181-200).
In wireless networks, relaying and user cooperation offer several attractive benefits such as higher throughput, better power efficiency, and larger coverage. As a result, cooperative networks are regarded as one of the most promising enabling technologies able to meet the increasingly high rate demands and quality of service requirements in wireless networks. In this dissertation, we investigate the efficient design of cooperative wireless networks from the perspectives of robust resource allocation, wideband communications, and energy efficiency. Given that the primary resource to be allocated is the relay node's transmission power, we propose robust and efficient relay power allocation algorithms when the global channel state information is subject to uncertainty. In addition, we propose practical algorithms that do not require frequent tracking of the global channel state information. This work reveals that ignoring global channel state information uncertainties and solving the relay power optimization problems often lead to poor performance, highlighting the importance of robust algorithm designs in practical wireless networks. Wideband cooperative networks allow for both higher data rate and higher resistance to interference. Since the gains achieved by using cooperation come at the cost of higher node complexity and substantial coordination overhead, it is important to study practical low-complexity signaling and receiver schemes suitable for wideband networks. In particular, we consider transmitted-reference signaling schemes and provide a unified performance analysis in terms of bit error rate. Since wideband networks are expected to coexist with many existing narrowband systems, it is important to characterize the effect of narrowband interference. We further extend the performance analysis of transmitted-reference signaling schemes to include the effect of narrowband interference..
(cont) Finally, we conclude by studying the benefits of cooperation in a wireless sensor network, which aims at detecting the presence or absence of a certain physical phenomenon of interest using geographically dispersed sensor nodes. We propose a consensus flooding protocol and analyze its average energy consumption. We investigate the tradeoff between the detection reliability and the energy efficiency when nodes are allowed to cooperate. By addressing the above design challenges, this dissertation will be useful for obtaining insight into the theory and application of cooperative networks in future communication systems
by Tony Q.S. Quek.
Ph.D.
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Balcioglu, Yalcin. "Integrated V2V Wireless Network and Vehicular Traffic Simulator Design." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1243957942.
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Zheng, Chenyu. "Ultra-low power energy harvesting wireless sensor network design." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/18812.
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Master of ScienceDepartment of Electrical and Computer Engineering
William B. Kuhn and Balasubramaniam Natarajan
This thesis presents an energy harvesting wireless sensor network (EHWSN) architecture customized for use within a space suit. The contribution of this research spans both physical (PHY) layer energy harvesting transceiver design and appropriate medium access control (MAC) layer solutions. The EHWSN architecture consists of a star topology with two types of transceiver nodes: a powered Gateway Radio (GR) node and multiple energy harvesting (EH) Bio-Sensor Radio (BSR) nodes. A GR node works as a central controller to receive data from BSR nodes and manages the EHWSN via command packets; low power BSR nodes work to obtain biological signals, packetize the data and transmit it to the GR node. To demonstrate the feasibility of an EHWSN at the PHY layer, a representative BSR node is designed and implemented. The BSR node is powered by a thermal energy harvesting system (TEHS) which exploits the difference between the temperatures of a space suit's cooling garment and the astronaut's body. It is shown that through appropriate control of the duty-cycle in transmission and receiving modes, it is possible for the transceiver to operate with less than 1mW power generated by the TEHS. A super capacitor, energy storage of TEHS, acts as an energy buffer between TEHS and power consuming units (processing units and transceiver radio). The super capacitor charges when a BSR node is in sleep mode and discharges when the node is active. The node switches from sleep mode to active mode whenever the super capacitor is fully charged. A voltage level monitor detects the system's energy level by measuring voltage across the super capacitor. Since the power generated by the TEHS is extremely low(less than 1mW) and a BSR node consumes relatively high power (approximately 250mW) during active mode, a BSR node must work under an extremely low duty cycle (approximately 0.4%). This ultra-low duty cycle complicates MAC layer design because a BSR node must sleep for more than 99.6% of overall operation time. Another challenge for MAC layer design is the inability to predict when the BSR node awakens from sleep mode due to unpredictability of the harvested energy. Therefore, two feasible MAC layer designs, CSA (carrier sense ALOHA based)-MAC and GRI (gateway radio initialized)-MAC, are proposed in this thesis.
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Bouras, Ikram. "Fixed charge network design problem with user-optimal flows." Thesis, Montpellier, 2019. http://www.theses.fr/2019MONTS136.
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Cette thèse s'adresse à la classe des problèmes de conception de réseaux bi-niveaux. Nous nous sommes intéressés à l'étude des applications des différents domaines et au développement d'algorithmes exacts pour la résolution des problème de réseaux bi-niveau correspondants. En particulier, nous avons étudié le problème de conception de réseau bi-niveau dans lequel le ``leader" sélectionne une partie du réseau à activer, puis, dans le deuxième niveau, la solution doit être optimale pour un problème de flot dans le sous-réseau sélectionné. Dans cette thèse, trois applications de ce problème sont étudiées : le transport de matières dangereuses, les réseaux de télécommunication et les réseaux sociaux. Le problème de deuxième niveau dans la première et la dernière application est un problème de plus court chemin alors qu'un flot de coûts minimum est requis dans la deuxième application.Le premier problème étudié est le problème de conception de réseau avec coût fixe avec contraintes de plus court chemin. Le problème est modélisé comme un programme bi-niveaux qui peut être appliqué dans le transport des matières dangereuses. Pour ce problème, nous proposons deux nouvelles formulations de programmation en nombres entiers (PLNE) inspirées par des inégalités de chemin et de cycle. Nous incorporons ces formulations dans des algorithmes de branch-and-cut et de plans coupants. Des tests numériques sont effectués sur des instances réelles et sur un ensembles d'instances aléatoires qui sont générées avec différents critères pour examiner la difficulté de ces instances. Les résultats montrent que les algorithmes de plan coupants proposés peuvent résoudre jusqu’à 19% d’instances de plus que les formulations compactes.Le deuxième problème étudié concerne la gestion de la consommation d'énergie dans les réseaux de télécommunication en utilisant un protocole de routage multi-chemins pour minimiser la capacité des liens utilisée. Nous proposons un modèle d'optimisation bi-niveaux dans lequel le premier niveau représente la fonction de gestion de l'énergie et le deuxième est un protocole de routage multi-chemins. Ensuite, le problème est reformulé par des formulations PLNE en remplaçant le problème du deuxième niveau par ses conditions d'optimalité. Ces formulations sont utilisées pour résoudre le problème avec les algorithmes classiques de plans coupants et de branch-and-cut. Les expérimentations sont effectuées sur des instances réelles afin de comparer les algorithmes proposés et d'évaluer l'efficacité de notre modèle par rapport aux modèles existants à un seul chemin et de multi-objectifs.Enfin, nous étudions le problème de la maximisation d’influence dans les réseaux sociaux signés. A notre connaissance, c'est la première fois que ce problème est considéré comme un problème de programmation à deux niveaux. Nous reformulons le problème en modèles PLNE à un niveau en utilisant trois différentes conditions d'optimalité du problème de plus court chemin apparaissant dans le deuxième niveau. Ces formulations sont renforcées en ajoutant un ensemble d'inégalités valides. Des tests numériques sont effectués sur des instances aléatoires pour comparer les différentes formulations proposées. Enfin, des solutions optimales en temps polynomial sont proposées pour des cas particuliers des graphesThis thesis addresses a class of bi-level network design problems. We are interested in investigating applications from different domains and in developing exact algorithms to solve the corresponding bi-level network problem. In particular, we study a bi-level network design problem where the leader selects a part of the network to be activated, then, in the second level, the solution must be optimal for a network flow problem in the selected sub-network. In this thesis, three applications of this problem are studied: hazmats transportation, telecommunication, and social networks analysis. The second level problem in the first and the last applications is a shortest path problem while a minimum cost flow is required in the second application.The first studied problem is the fixed charge network design problem with shortest path constraints, which is modeled as a bi-level program and can be applied in hazardous transportation. For this problem, we propose two new binary integer programming (BILP) formulations inspired by path and cycle inequalities. We incorporate these formulations in a branch-and-cut algorithm and another cutting-plane based method. Numerical experiments are performed on real instances, and random data sets generated with different criteria to examine the difficulty of the instances. The results show that the proposed cutting plane algorithms can solve up to 19% more instances than the compact formulations.The second studied problem is the energy-aware traffic engineering while using multi-path routing to minimize link capacity utilization in ISP backbone networks. We propose a bi-level optimization model where the upper level represents the energy management function, and the lower one refers to the deployed multi-path routing protocol. Then, we reformulate it as a one-level MILP replacing the second level problem by different sets of flow optimality conditions. We further use these formulations to solve the problem with classical cutting plane and branch-and-cut algorithms. The computational experiments are performed on real instances to compare the proposed algorithms and to evaluate the efficiency of our model against existing single-path and multi-objective models.Finally, we study the problem of maximization influence in signed social networks. To the best of our knowledge, it is the first time that this problem is modeled as a bi-level programming problem. We reformulate the problem as one-level MILP models using three different optimality conditions of the shortest path problem appearing in the second level. These formulations are strengthened by adding a set of valid inequalities. Computational experiments are performed using random instances to compare the different proposed formulations. Finally, explicit solutions and bounds are proposed for particular cases of instances
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Yin, Li. "Sensor network coverage and data aggregation problem: solutions toward the maximum lifetime." Diss., Rolla, Mo. : University of Missouri-Rolla, 2007. http://scholarsmine.mst.edu/thesis/pdf/Yin_09007dcc803c1aa0.pdf.
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Thesis (M.S.)--University of Missouri--Rolla, 2007.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 26, 2007) Includes bibliographical references (p. 51-55).
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Oudit, Suzanne Riggs Lloyd Stephen. "Design of an outdoor wireless local area network and antenna analysis." Auburn, Ala., 2006. http://repo.lib.auburn.edu/2006%20Summer/Theses/OUDIT_SUZANNE_45.pdf.
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Cui, Nenghui. "Wireless Sensor Networks - Network Coded Cooperative Communication : Design and Implementation." Thesis, Uppsala universitet, Institutionen för informationsteknologi, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-188750.
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This thesis is concerned with the design and implementation of a testbed for network coded cooperative communication (NC-CC) in IEEE 802.15.4-based wireless sensor networks (WSNs). The work and test are based on Contiki 2.5 and sensor nodes Zolertia Z1. In the testbed, a new network framework with large extensibility is provided, as well as a basic realization of NC-CC. In our implementation, CC is realized as a Rime primitive in Contiki, while NC is inserted as a new layer between Rime and MAC to perform opportunistic coding. In this way the network stack of Contiki is extended while still keeping the backward compatibility. Because of the lack of multicast in IEEE 802.15.4 protocol and the contradiction of applying continuous overhearing on power-constraint sensor nodes, new mechanisms called pseudo overhearing and pseudo multicast is proposed in our testbed. A configurable test program is also designed for the purpose of evaluation. A combination of two senders, one relay and one destination is used as our network model. Experiments show that all the designed functions work properly. But to be robust, more experiments under different models should be brought in the future. A more detailed report on the experiments can be found in my project-partner Yitian Yan’s thesis.
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Prokić, Miloš. "Low-rate wireless personal area network coordinator design and implementation." Thesis, McGill University, 2005. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=99009.
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This thesis presents low-rate personal area network coordinator design and implementation on both hardware and software fronts.It portrays integration techniques used to enhance the existing wireless sensor network infrastructure previously developed by the Microelectronics research group. The infrastructure was made for data collection and sharing during educational conferences and alike gatherings. The system is designed to be flexible and rapidly reprogrammable, while keeping low-power and low-cost as the primary design objectives.
Augmenting the hardware is the wireless network protocol specifically conceived for low-power and low-rate applications - IEEE 802.15.4. Both application and implementation aspects were covered in order to produce a portable and expandable embedded software design.
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Balcioglu, Yalcin. "Integrated V₂V wireless network and vehicular traffic simulator design." Columbus, Ohio : Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1243957942.
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Kandah, Farah Issa. "A Secure and Reliable Interference-Aware Wireless Mesh Network Design." Diss., North Dakota State University, 2012. https://hdl.handle.net/10365/26479.
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A wireless mesh network (WMN) is a multihop wireless network consisting of a large number of wireless nodes of which some are called gateway nodes and connected with a wired network. Wireless mesh network have attracted much research attention recently due to its flexibility, low-cost and robustness, which facilitate its usability in many potential applications, including last-mile broadband Internet access, neighborhood gaming, Video-on-Demand (VoD), distributed file backup, video surveillance, etc. The broadcast nature, the lack of infrastructure as well as the flexible deployment nature of wireless mesh networks make it different from wired networks, therefore more attention in designing the wireless mesh network is needed to maintain a good performance of this promising technology. We, in this study, investigate the wireless mesh network design taking into consideration three design factors seeking an improvement in the network performance by reducing the interference influence in the network, improving the network reliability to satisfy more requests, and securing the network against malicious eavesdropping attacks. Our design is presented into three sub-problems; sub-problem (1), which seeks an interference-aware robust topology control scheme, sub-problem (2) which seeks a multipath routing scheme, and sub-problem (3) which seeks a secure key management scheme. Through simulations and comparisons with previous work, we show that our proposed solutions outperform previous schemes in providing a better network performance in terms of reducing the network interference, satisfying more number of requests and increasing the network resistance to malicious eavesdropping attacks.
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Lei, Wei-Neng, and 雷惟能. "Design and Analysis of Adaptive Receiver Transmission Protocols for Receiver Blocking Problem in Wireless Ad-Hoc Networks." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/66523767069790195596.
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碩士國立交通大學
電信工程研究所
99
Due to the lack of a centralized coordinator for wireless resource allocation, the design of medium access control (MAC) protocols is considered crucial for throughput enhancement in the wireless ad-hoc networks. The receiver blocking problem, which has not been studied in most of the MAC protocol design, can lead to severe degradation on the throughput performance. In this paper, the multiple receiver transmission (MRT) and the fast NAV truncation (FNT) mechanisms are proposed to alleviate the receiver blocking problem without the adoption of additional control channels. The adaptive receiver transmission (ART) scheme is proposed to further enhance the system throughput with dynamic adjustment of the selected receivers. Analytical model is also derived to validate the effectiveness of the proposed ART protocol. Simulations are performed to evaluate and compare the proposed three protocols with existing MAC schemes. It can be observed that the proposed ART protocol outperforms the other schemes by both alleviating the receiver blocking problem and enhancing the system throughput for the wireless multi-hop ad-hoc networks.
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Shankaraiah, *. "Design And Development Of Solutions To Some Of The Networking Problems In Hybrid Wireless Superstore Networks." Thesis, 2011. http://etd.iisc.ernet.in/handle/2005/2430.
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Hybrid Wireless Networks (HWNs) are composite networks comprises of different technologies, possibly with overlapping coverage. Users with multimode terminals in HWNs are able to initiate connectivity that best suits their attributes and the requirements of their applications. There are many complexities in hybrid wireless networks due to changing data rates, frequency of operation, resource availability, QoS and also, complexities in terms of mobility management across different technologies.
A superstore is a very large retail store that serves as a one-stop shopping destination by offering a wide variety of goods that range from groceries to appliances. It provide all types services such as banking, photo center, catering, etc. The good examples of superstores are: Tesco (hypermarkets, United Kingdom), Carrefour(hypermarkets, France), etc.
Generally, the mobile customer communicates with superstore server using a transaction. A transaction corresponds to a finite number of interactive processes between the customer and superstore server. A few superstore transactions, examples are, product browsing, Technical details inquiry, Financial transactions, billing, etc.
This thesis aims to design and develop the following schemes to solve some of the above indicated problems of a hybrid wireless superstore network:
1 Transaction based bandwidth management.
2 Transaction-based resource management.
3 Transaction-based Quality of Service management.
4. Transactions-based topology management. We, herewith, present these developed schemes, the simulation carried out and results obtained, in brief.
Transaction-based bandwidth management
The designed Transaction-Based Bandwidth Management Scheme (TB-BMS) operates at application-level and intelligently allocates the bandwidth by monitoring the profit oriented sensitivity variations in the transactions, which are linked with various profit profiles created over type, time, and history of transactions. The scheme mainly consists of transaction classifier, bandwidth determination and transactions scheduling modules. We have deployed these scheme over a downlink of HWNs, since the uplink caries simple quires from customers to superstore server. The scheme uses transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available BW.
As we observe, not all superstore transactions can have the same profit sensitive information, data size and operation type. Therefore, we classify the superstore transactions into four levels based on profit, data size, operation type and the degree of severity of information that they are handling. The aim of transaction classification module is to find the transaction sensitivity level(TSL) for a given transaction.
The bandwidth determination module estimates bandwidth requirement for each of the transactions. The transactions scheduling module schedules the transactions based on availability of bandwidth as per the TSL of the transaction. The scheme schedules the highest priority transactions first, keeping the lowest priority transaction pending. If all the highest priority transactions are over, then it continues with next priority level transactions, and so on, in every slot. We have simulated the hybrid wireless superstore network environment with WiFi and GSM technologies. We simulated four TSL levels with different bandwidth. The simulation under consideration uses different transactions with different bandwidth requirements.
The performance results describe that the proposed scheme considerably improves the bandwidth utilization by reducing transaction blocking and accommodating more essential transactions at the peak time of the business.
Transaction-based resource management
In the next work, we have proposed the transaction-based resource management scheme (TB-RMS) to allocate the required resources among the various customer services based on priority of transactions. The scheme mainly consists of transaction classifier, resource estimation and transactions scheduling modules. This scheme also uses a downlink transaction scheduling algorithm, which decides how to schedule an outgoing transaction based on its priority with efficient use of available resources.
The transaction-based resource management is similar to that of TB-BMS scheme, except that the scheme estimates the resources like buffer, bandwidth, processing time for each of transaction rather than bandwidth.
The performance results indicate that the proposed TB-RMS scheme considerably improves the resource utilization by reducing transaction blocking and accommodating more essential transactions at the peak time.
Transaction-based Quality of Service management
In the third segment, we have proposed a police-based transaction-aware QoS management architecture for the downlink QoS management. We derive a policy for the estimation of QoS parameters, like, delay, jitter, bandwidth, transaction loss for every transaction before scheduling on the downlink. We use Policy-based Transaction QoS Management(PTQM) to achieve the transaction based QoS management. Policies are rules that govern a transaction behavior, usually implemented in the form of if(condition) then(action) policies.
The QoS management scheme is fully centralized, and is based on the ideas of client-server interaction. Each mobile terminal is connected to a server via WiFi or GSM. The master policy controller (MPDF) connects to the policy controller of the WiFi network (WPDF)and the GSM policy controller(PDF).
We have considered the simulation environment similar to earlier schemes. The results shows that the policy-based transaction QoS management is improves performance and utilizes network resources efficiently at the peak time of the superstore business.
Transactions-Aware Topology Management(TATM)
Finally, we have proposed a topology management scheme to the superstore hybrid wireless networks. A wireless topology management that manages the activities and features of a wireless network connection. It may control the process of selecting an available access points, authentication and associating to it and setting up other parameters of the wireless connection.
The proposed topology management scheme consists of the transaction classifier, resource estimation module, network availability and status module and transaction-aware topology management module. The TATM scheme is to select the best network among available networks to provide transaction response(or execution).
We have simulated hybrid wireless superstore network with five WiFi and two GSM technologies. The performance results indicate that the transaction-based topology management scheme utilizes the available resources efficiently and distributed transaction loads evenly in both WiFi and GSM networks based on the capacity.
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Chen, Szu-Jung, and 陳思蓉. "Approximating the Wireless Sensor Network Scheduling Problem." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/03284455701819190238.
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碩士國立清華大學
工業工程與工程管理學系
102
A wireless sensor network (WSN) consists of one or more wireless data collectors and many autonomous sensors to monitor physical phenomena or collect environmental information. Each sensor usually uses a battery to enable its function, which limits its lifetime. In order to prolong the lifetime of WSNs, it is important to schedule the sensors to be activated in WSNs, which is called the wireless sensor network scheduling problem. The WSN scheduling problem is described as follows: Given a set of sensors, and a set of regions to be monitored, each region can be monitored by a subset of the sensors, and a sensor also can monitor more than one region. In order to prolong the lifetime of WSN, we decompose the sensors into disjoint subsets such that every subset of sensors needs to monitor all the regions, i.e. activating a subset of sensors to observe all the regions in each time slot, and the number of times slots (i.e. the number of subsets of sensors), that is, the lifetime of the WSN, is maximized. We investigate the WSN scheduling problem in two different models, and provide several polynomial time algorithms for approximating this problem. When the monitored range of each sensor is the same, i.e. the distance r, and the distance between any two regions is at least √3 r+ε, we present a 3/4 -ratio approximation algorithm to solve the WSN scheduling problem. In addition, when every monitored region is represented by a closed area, and each sensor can monitor at most three regions, we provide a 3/8 -ratio approximation algorithm to solve this model. Moreover, we also can identify critical sensors of WSNs; a sensor is called critical if the lifetime of WSNs must decrease when the sensor is broken. The identification of critical sensors can assist the reliability analysis of wireless sensor networks.
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Chen, Lijun. "Wireless Network Design and Control." Thesis, 2007. https://thesis.library.caltech.edu/5160/1/Thesis.pdf.
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Optimization theory and game theory provide a suite of tools that are flexible in modelling various network systems, and a rich series of equilibrium solution concepts and convergent algorithms. In this thesis, we view network protocols as distributed algorithms achieving the corresponding network equilibria, and study wireless network design and control in optimization and game-theoretic frameworks.
Specifically, we first take a holistic approach and design an overall framework for the protocol architecture in ad hoc wireless networks. The goal is to integrate various protocol layers into a unified framework, by regarding them as distributed computations over the network to solve some optimization problem. Our current theory integrates three functions--congestion control, routing and scheduling--in transport, network and link layers into a coherent framework. These three functions interact through and are regulated by congestion price so as to achieve a global optimality, even in a time-varying environment. This framework is promising to be extended to provide a mathematical theory for network architecture, and to allow us to systematically carry out cross-layer design.
We then develop a general game-theoretic framework for contention control. We define a general game-theoretic model, called random access game, to study the contention/interaction among wireless nodes, and propose a novel medium access method derived from carrier sensing multiple access with collision avoidance in which each node estimates its conditional collision probability and adjusts its persistence probability or contention window, according to a distributed strategy update mechanism achieving the Nash equilibrium of random access game. This results in simple dynamics, controllable performance objectives, good short-term fairness, low collision, and high throughput. As wireless nodes can estimate conditional collision probabilities by observing consecutive idle slots between transmissions, we can decouple contention control from handling failed transmissions. This also opens up other opportunities such as rate adaptation to channel variations. In addition to providing a general and systematic design methodology for medium access control, the random access game model also provides an analytical framework to understand the equilibrium properties such as throughput, loss and fairness, and dynamic properties of different medium access protocols and their interactions.
Finally, we conclude this work with some suggestions for future research.
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Yeh, Kai-Wen, and 葉凱文. "Microcontroller Design for Wireless Sensor Network." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/09021155646182609613.
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碩士國立臺灣大學
電子工程學研究所
97
Distance medical treatment will become an important issue in upcoming ageing society. As a result of the advancement of semiconductor manufacturing technology, it is possible to integrate wireless transceiver, sensors, amplifier and digital controller into one single chip. This is called a SOC (System‐on‐Chip) chip. Hardware cost and size of a WSN (Wireless Sensor Network) sensor node can be reduced substantially using SOC technology and suitable for distance medical treatment. We achieved a SOC chip for WSN sensor node using TSMC 0.35 μm Mixed‐signal 2P4M CMOS technology. It is composed of a microcontroller, an ADC (analog‐to‐digital convertor), an Instrument Amplifier, a trans‐impedance amplifier, an analog multiplexer, a ASK transmitter, an OOK receiver, 5 regulators, a crystal oscillator and power‐on‐reset circuit. Size of the SOC chip including 117 ESD PADs is 3298*3637μm^2 The microcontroller is fully compatible with common 8051 MCUs. It has 111 instructions. The core of the microcontroller is pipeline architecture with 5‐stages. An instruction can be executed in only one clock period. 4096 bytes program memory and 256 bytes data memory are embedded. Peripherals such as UART transceivers with hardware CRC module, clock‐divider, and timer are also implemented. Maximum clock frequency of the microcontroller is 36MHz (i.e. 18MIPS). Power consumption is 1.172mA when the chip operates at 4MHz. Lower power design is a critical issue for WSN sensor node. Clock‐gating technique and clock‐multiplexing are used to reduce power dissipation of digital circuits. Regulators with switches are used to reduce power dissipation of analog and RF circuits. Each analog / RF block can be turned on or off separately.
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Su, Yu-Chang, and 蘇裕彰. "Equalizer Design for HiperMAN Wireless Network." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/96529245492196152973.
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碩士國立中興大學
電機工程學系所
94
HiperMAN (High Performance Radio Metropolitan Area Network) is a standard created by ETSI (European Telecommunications Standards Institute) BRAN (Broadband Radio Access Networks) group to provide inter-operable broadband fixed wireless communication access in the 2 - 11GHz radio frequency bands across Europe HiperMAN is optimised for packet switched networks, and fixed and nomadic applications, primarily in the residential and small business user environments. In HiperMAN system, it is composed of three parts, including channal coding, modulation and orthogonal frequency division multiplexing (OFDM) system. The objective of this project is model and simulate the ETSI HiperMAN OFDM physical layer using MATLAB. The simulation will compare the performance of two different receiver models. In the first method, we only use the pilot signal to adjust the parameters of the equalizer, and in next we use all data passed by channel to adjust the parameters.
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Lin, Ting-Yu, and 林亭佑. "Design and Analysis of Data Communication Problems in Bluetooth Wireless Personal-Area Networks." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/82185476981270189855.
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博士國立交通大學
資訊工程系
91
As an emerging personal-area networking solution, Bluetooth technology is highly expected to play an important role in the evolution of wireless communications. Bluetooth was originally viewed as a way of cable replacement, and later found that it was capable of more than this purpose. With low-cost Bluetooth modules available on market, a large deployment of Bluetooths is very likely to take place in the near future. In this thesis, we focus on Bluetooth-related data communication issues and propose a series of solutions or evaluation results to them. The details of related works are described below. One essential issue for almost all kinds of portable devices is power saving. This could be even more important for Bluetooth, which has a design goal of being very compact. Bluetooth has a master-slave configuration, called a piconet. Since the master device is the central controller in a piconet, we do not put such device into sleep mode to save power. On the other hand, slave devices, with less responsibility, can enter power-saving mode to reduce unnecessary battery energy expenditure. In the first work, we study the problem of managing the low-power sniff mode in Bluetooth, where a slave is allowed to be awake only periodically. One challenging problem is how to schedule each slave's sniffing period in a piconet so as to resolve the tradeoff between traffic requirement and power-saving requirement, to which we refer as the sniff-scheduling problem. We propose an adaptive protocol to dynamically adjust each slave's sniff parameters, with a goal of catching the varying, and even asymmetric, traffic patterns among the master and slaves. Unspecified in the Bluetooth standard, the link polling policy adopted by a master may significantly influence the bandwidth utilization of a piconet. In the second work, we propose a Pattern Matching Polling (PMP) policy for data link scheduling to efficiently use the limited bandwidth. A polling pattern is a sequence of Bluetooth packets of different type combinations to be exchanged by a master-slave pair that can properly reflect the traffic ratio (i.e., asymmetry) of the pair. By judiciously selecting a proper polling pattern together with polling times for the link, the precious wireless bandwidth can be better utilized. The ultimate goal is to reduce the unfilled, or even null, payloads in each busy slot. In addition, an overflow mechanism is included to handle unpredictable traffic dynamics. A larger-area Bluetooth network can be formed by interconnecting multiple piconets, called scatternet. However, the structure of scatternets is not defined in the Bluetooth specification and remains as an open issue at the designers' choice. It is desirable to have simple yet efficient scatternet topologies with well supports of routing protocols, considering that Bluetooths are to be used for personal-area networks with design goals of simplicity and compactness. In the literature, although many routing protocols have been proposed for mobile ad hoc networks}, directly applying them poses a problem due to Bluetooth's special baseband and MAC-layer features. In the third work, we propose an attractive scatternet topology called BlueRing which connects piconets as a ring interleaved by bridges between piconets, and address its formation, routing, and topology maintenance protocols. Finally, by sharing the same set of 79/23 frequency channels, a Bluetooth piconet will inevitably encounter the interference problem from other piconets. With a special channel model and packet formats, one research issue is how to predict the packet collision effect in a multi-piconet environment. The analysis model proposed in our fourth work considers all three data packet types (1-/3-/5-slot) supported by Bluetooth, and remove the assumption that each piconet must be fully loaded. Thus our result reflects a more general scenario.
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"The multi-level network design problem." Sloan School of Management, Massachusetts Institute of Technology, 1991. http://hdl.handle.net/1721.1/2381.
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Shu, Jia, Chung Piaw Teo, and Zuo-Jun Max Shen. "Stochastic Transportation-Inventory Network Design Problem." 2002. http://hdl.handle.net/1721.1/4018.
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In this paper, we study the stochastic transportation-inventory network design problem involving one supplier and multiple retailers. Each retailer faces some uncertain demand. Due to this uncertainty, some amount of safety stock must be maintained to achieve suitable service levels. However, risk-pooling benefits may be achieved by allowing some retailers to serve as distribution centers (and therefore inventory storage locations) for other retailers. The problem is to determine which retailers should serve as distribution centers and how to allocate the other retailers to the distribution centers. Shen et al. (2000) and Daskin et al. (2001) formulated this problem as a set-covering integer-programming model. The pricing subproblem that arises from the column generation algorithm gives rise to a new class of submodular function minimization problem. They only provided efficient algorithms for two special cases, and assort to ellipsoid method to solve the general pricing problem, which run in O(n⁷ log(n)) time, where n is the number of retailers. In this paper, we show that by exploiting the special structures of the pricing problem, we can solve it in O(n² log n) time. Our approach implicitly utilizes the fact that the set of all lines in 2-D plane has low VC-dimension. Computational results show that moderate size transportation-inventory network design problem can be solved efficiently via this approach.Singapore-MIT Alliance (SMA)
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Chiang, Hua-han, and 江華瀚. "The Research of Routing Problem In Industrial Wireless Sensor Network." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/57824786343947069110.
Full textAbstract:
碩士國立雲林科技大學
資訊工程系碩士班
101
Wireless sensor network in industrial environment (denoted IWSN) requires low data delivery time from sensor node to sink node. Due to the dynamic routing and transmission collision, the data delivery time in IWSN is unpredictable. From the power consumption point, the sensor nodes which close to the sink node incur more power consumption for forwarding the data to sink node. In this paper, a proactive routing which constructs the sensor nodes in IWSN into circular chain topology (i.e., ring topology) to avoid the data collision problem. The IWSN circular chain construction problem is converted to the traveling salesman problem (TSP) and solved by the genetic algorithm. We also develop a heuristics algorithm to adjust the circular chain to the load-balance chain. The computer simulation results reveal that the constructed load-balance chain has the less data delivery time and more system working life time.
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Lin, Chin-Yi, and 林璟頤. "An Efficient Deployment Strategy Optimizes Wireless Sensor Network Topology Problem." Thesis, 2014. http://ndltd.ncl.edu.tw/handle/50367228454966030718.
Full textAbstract:
碩士國立暨南國際大學
資訊工程學系
103
The Wireless sensor network is a very important issue, if you do not placed a good position will result in more than the number of sensors placed, and the coverage is too low or high load sensor attached to shorten lifetime time. And even some serious problems might occur, For example: forest fire occurs, low coverage cannot detect a fire and sensor lifetime to short time to cannot tracking, May cause more serious disaster. We will deploy for wireless sensor networks, in the sensor network connectivity sensing and event detection rate of satisfaction, from the total number of sensors used and the power consumption of the entire system to do the optimization.
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Chen, Yong-Chang, and 陳永昌. "Microcontroller Design for Wireless Bio-Sensor Network." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/66224498694933243125.
Full textAbstract:
碩士臺灣大學
電子工程學研究所
97
Owing to the Population ageing in the world, many countries include Taiwan have become an aged society which is defined by United Nations. How to assist senior citizens’ life will become an important topic in the future. Depending on the advancement of semiconductor manufacturing technology, it has become a major trend presently to implement a small, low-cost and lower-power system-on-a-chip. This thesis achieved a kind of sensor applied to biomedicine in Wireless Sensor Network, which could be supplied the demand for distance medical treatment. We used TSMC 0.35 μm 2P4M CMOS process to achieve a system-on-a-chip used as a sensor node in Wireless Bio-Sensor Network. The chip includes Microcontroller, On/Off Keying receiver, Amplitude-Shift Keying transmitter, Instrument Amplifier, Analog-to-Digital Convertor, Trans-Impedance Amplifier, Analog Multiplexer and Voltage Regulators. The Microcontroller is programmable and compatible with standard 8051 Instruction Set. We use a new and real five-stage pipeline architecture to improve overall system performance. The programmable Microcontroller contains 8-bits data bus and 12 bits address bus, it can execute 111 instructions. It also equips 256 bytes data memory and 4096 bytes program memory, two timers, clock-divider, two Universal Asynchronous Receiver/Transmitter with Cyclic Redundancy Checks, 8 types of interrupt. Maximum clock rate of the microcontroller can achieve 40MHz. Power consumption is 1.135mA when the applied rate is 4MHz in general. Total chip area of the SOC is 3167μm*3396μm.
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Han, Cheng Chun, and 鄭淳瀚. "Integration of EPC Network and Wireless Sensor Network for Heterogeneous Network Gateway Design." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/t25r2b.
Full textAbstract:
碩士國立臺東大學
資訊管理學系碩士班
97
The most critical technologies in the third wave of computing called ubiquitous network are RFID and Wireless sensor network. Both of them not only have high research expansion but also wide application popularity. Although we have the high popularity of RFID and WSN, yet the insufficient welcome calculation and effective data framework lead to disintegrated setting and protocol. This thesis aims at the integration of RFID and WSN, which is the combination of features of the instantaneity of WSN and the consistency and convenience of RFID EPC. This groundbreaking combination can create a compound system to provide a convenient environment for users to choose what they need for their works. On the other hand, facing the upcoming of digital family, the internet and its peripheral equipments are more crucial to families and firms. We also plan to adopt OSGi to build an OSGi Gateway in the future. We can execute this process through OSGi Framework in order to accelerate the integration of heterogeneous networks in digital family.
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Lu, Tsung-Yi, and 呂宗益. "Adaptive Wireless Sensor Network Platform Design And Implement." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/79538543806894697562.
Full textAbstract:
碩士國立交通大學
電機學院碩士在職專班電機與控制組
99
Recently, wireless sensor network(WSNs) is applied massively in high real time, low cost, high reliability, high robustness structural health monitoring system. Extended network system operation life time and energy efficiency is discussed frequently. Most method are focus in how to efficiency transmit and receive data for extended system life time. The present majority's method will centralize the data in some specific node and transmit to the terminal gateway. This method possibly causes the partial nodes to die fast. This paper design and implement dynamic change network structure by control center that perform optimization energy algorithem in single terminal gateway and Non-mobile wireless sensor network configuration. This adaptive wireless sensor network platform is based on the physical layer and media access layer of low power consumption standard IEEE 802.15.4 and develops the adaptive network layer and application layer according to system transmission and energy requirements. This study development wireless sensor network hardware, system firmware, network layer protocol and application layer.
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Chin, Wu Meng, and 吳孟勤. "RF Frequency Convertor Design For Broadband Wireless Network." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/14789843456737096826.
Full textAbstract:
碩士中華大學
電機工程學系碩士班
100
Because various types of mobile devices become popular, customers using 3.5G services are also increased. Although 3.5G base stations cover widely, the increase of Internet users has resulted in sharp decline in the transmission data rate. Recently, 3.5GHz communication capacity tends to be saturated in metropolitan areas. In order to reduce the burden of data transfer for the 3.5G network, this thesis presents the Wi-Fi Frequency Conversion technology then base station to mobile station communication can uses Wi-Fi protocol in the specified frequency band. It can provide high-speed Internet access needs. This thesis proposed RF frequency convertor design for broadband wireless network compatible with the 802.11a/g/n standards. The frequency convertor allows input frequency band from 5.15GHz to 5.55GHz and output frequency from 3.4GHz to 3.8GHz which provides 400MHz bandwidth. Frequency convertor design includes system frequency planning and budget analysis. The power amplifier at 3.6GHz can reach 25dBm@2.5%EVM output power and support a long transmission distance over 7 km.
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jing-yi，xu and 許靜宜. "Wireless sensor network communication module design and testing." Thesis, 2012. http://ndltd.ncl.edu.tw/handle/28738672057751992070.
Full textAbstract:
碩士中華大學
電機工程學系碩士班
100
The purpose of this thesis is based on the design and testing of the miniaturized antenna for wireless sensor network communication module. The design goals of the communication distance is required to reach 50 ~ 100m. Taking into account the cost reduction, the miniaturized antennas will be integrated in ZigBee module PCB board. The contents of this thesis include PIFA (Planar Inverted-F Antenna) antenna design, the balun circuit design and adjustment of the operating frequency in order to comply with the IEEE 802.15.4 the ZigBee standards. Newly designed miniaturized PIFA antenna radiation pattern simulation results are consistent with the measured results. Balun circuit design uses the transmission lines and passive components. Differential impedance as seen from the RF port towards the antenna will be matched to TI CC2530 optimum load impedance. Finally, we will show the system measurement results of the ZigBee modules. In the condition of output power 4.5dBm, when the communication distance is close to 100m, PER are still less than 1%. Keyword: ZigBee、CC2530、Planar Inverted-F Antenna、Antenna pattern。
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LIN, CHENG-HON, and 林建宏. "Wireless Communications Network Design and Management Considering Sectorization." Thesis, 2000. http://ndltd.ncl.edu.tw/handle/45740123294867740813.
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碩士國立臺灣大學
資訊管理研究所
88
In this thesis, research shall be conducted to study relative topics in wireless network planning and management. The objective of this thesis is to provide planners and managers of an integrated wireless network with both decision support and operation support with respect to network planning and management, so that the total network deployment and operation cost can be minimized under these constraints of QoS (quality of service). The proposed functionality of this thesis contains the following five topics: (i) MTSOs configuration and capacity assignment problem; (ii) the wired backbone circuit-switching network topology design problem; (iii) base station allocation, antenna configuration of each base station and power control problem; (iv) channels assignment problem; (v) high reliability of system problem. These problems have positive and negative effects on one another. Because of the complexity of this problem, we use Lagrangean relaxation and subgradient method as our main methodology. The conclusions in this thesis are presented in terms of formulation, sectorization and performance. In terms of formulation, we model a mathematical expression to describe the fixed sectorization problem. At the same time, we consider not only non-uniform size cell but also non-uniform traffic demand. In this point, our model is more generic. Because of the complexity of this problem, we use Lagrangean relaxation and subgradient method as our main methodology. When using these mathematical tools, they can provide us some hints to improve our heuristics. In terms of sectorization, we find that sectorization is less useful when one base station needs fewer channels. In other words, the wastage of resource fragmentation is more significant than the gains of sectorization. By increasing the number of channels required by one base station, the advantage of sectorization is more evident. In terms of performance, our Lagrangean relaxation based solution has more significant improvement than other intentional algorithms.
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Wan, Yu-Chang, and 萬育章. "LTE Multiband Antenna Design for Wireless Network Applications." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/7nrv6y.
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碩士國立臺北科技大學
電子工程系
106
To adapt the trend for the 4G LTE ( 4 Generation Long Term Evolution), this research paper is going to present the antenna for supporting 4G multi-band. Its applied on the wireless router and makes the channel selection more flexible with the WiSprys RF-MEMS technology. Eventually, to execute a system of the MIMO and adjust the high isolation. In this case, antenna is made by the techniques of the FR4 PCB. To meet the requirement from the different telecommunication operators, the author uses CPW-fed Monopole antenna which can apply the LTE Band 28/8/3/7. The traditional antennas generally lose the gains for the bandwidths. In order to overcome that, the author uses WiSprys RF-MEMS technology to make more advantageous Impedance matching. In the measuring results, the operating frequency can actually cover LTE Band 28/8/3/7, that covering the Band of the 4G FDD-LTE. The radiation pattern which is closed to Omni-direction is suitable for the antenna for wireless router. In LTE Band 28, the measured peak radiation gain and efficient are 0.08 dBi and 30 %. In LTE Band 8, the measured peak radiation gain and efficient are 0.57 dBi and 40 %. In LTE Band 3, the measured peak radiation gain and efficient are 1.61 dBi and 50 % and in LTE Band 7, the measured peak radiation gain and efficient are 2.99 dBi and 55%. On the other hand, the calculated results of MIMO system of the envelope correlation coefficient in all of the operating frequency band meet isolation requirement.
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ZENG, YU-WEI, and 曾郁惟. "Planar Spiral Antenna Design for Broadband Wireless Network." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/8qnm46.
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碩士中華大學
電機工程學系
107
This paper proposes two antenna designs, one-armed spiral and two-armed helical antenna. The two working frequency bands are designed to be 2.4GHz~2.5GHz, and the antenna size is less than 41mm in diameter. In this thesis, the PI substrate is used as the substrate material. The first antenna is designed as a single-arm spiral coil. The thickness of the substrate is 0.07mm, copper is 1oz, diameter is 40.2mm, line width is 0.5mm, line spacing is 1mm, and it is fed by 50Ω coaxial transmission line. (1) According to the HFSS simulation results, the Return Loss of 2.4 GHz is -16.74 dB, the Return Loss of 2.5 GHz is -14.3 dB, the antenna operating frequency band is 2.13 GHz to 3 GHz, and the ratio of the bandwidth to the center frequency is 34%. (2) Actual measurement results The Return Loss at 2.4 GHz is -14.13 dB, the Return Loss at 2.5 GHz is -16 dB, the antenna operating frequency band is 2.32 GHz to 3 GHz, and the ratio of bandwidth to center frequency is 26%. The second antenna is designed as a double-arm spiral coil with a substrate thickness of 0.1 mm, copper 2 oz, diameter 33 mm, outer line width 1 mm, inner line width 0.2 mm, inner ring diameter 0.8 mm, and line spacing 0.5 mm. (1) As a result of HFSS simulation, the Return Loss of 2.4 GHz is -19.64 dB, the Return Loss of 2.5 GHz is -32.2 dB, the antenna operating frequency band is 2 GHz to 3 GHz, and the ratio of the bandwidth to the center frequency is 40%. (2) Actual measurement results The Return Loss of 2.4 GHz is -16.9 dB, the Return Loss of 2.5 GHz is -29 dB, the antenna operating frequency band is 2 GHz to 3 GHz, and the ratio of the bandwidth to the center frequency is 40%. From the above analysis, it can be known that the HFSS simulation can achieve the design goal and successfully verify the design concept of this type of antenna.
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Wang, Zi-Qin, and 王子勤. "System Design for Broadband Wireless Metropolitan Area Network." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/93928212550454278914.
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碩士淡江大學
電機工程學系碩士班
94
Rise of wireless network recently. In new wireless network spec IEEE802.16 which is also called WiMAX Design for WMAN . It emphasize the realtime service and assurance to bandwidth and QoS is required . This thesis simulation system capacity under the single chennel . which based on spec 802.16-2004 based OFDM TDD system . And different subchannel number of OFDMA based 802.16e . We simulation any kinds of Service of frame based and symbol based effect system capacity and analysis packet loss and buffer size . And last we propose different spectrum effect system capacity and bandwidth based on OFDM.
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Shih-Hao, Lee, and 李世豪. "DS-CDMA Wireless Communications Network Design and Management." Thesis, 2001. http://ndltd.ncl.edu.tw/handle/81242726245349764401.
Full textAbstract:
碩士國立臺灣大學
資訊管理研究所
89
In recent years, PCS (Personal Communication System) has been popularly used because of the convenience of wireless services and deregulation of communication industry. The diffusion and demand of mobile communication services are still growing rapidly nowadays. For capacity and application variance reasons, the 3G (3rd Generation) wireless communications system is burgeoning. Although there are many technology will provide 3G services, like W-CDMA and CDMA2000, their core technology are DS-CDMA. In this thesis, we investigate the joint DS-CDMA wireless communications networks design problem. A well design network should provide not only an acceptable quality of service (QoS) but also a survivable service. So in this thesis we consider not only the QoS of each O-D pair but also the network survivable factor. In the DS-CDMA systems, the interference model of it is different form the past systems because the same frequency band is reused in every cell. We have described several types of interference model in mathematical formulation. We develop a mathematical programming model to describe the joint design problem. It turns out to be a non-linear non-convex mixed integer programming problem. A set of heuristic solution procedures based on Lagrangean relaxation methods is proposed to solve the complicated problem. From the computational experiments, our Lagrangean relaxation based algorithms achieve mush more improvements than other primal based heuristic.