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1
Nsoh, Stephen Atambire. "Resource allocation in WiMAX mesh networks". Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science, c2012, 2012. http://hdl.handle.net/10133/3371.
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The IEEE 802.16 standard popularly known as WiMAX is at the forefront of the technological
drive. Achieving high system throughput in these networks is challenging due to
interference which limits concurrent transmissions. In this thesis, we study routing and link
scheduling inWiMAX mesh networks. We present simple joint routing and link scheduling
algorithms that have outperformed most of the existing proposals in our experiments. Our
session based routing and links scheduling produced results approximately 90% of a trivial
lower bound.
We also study the problem of quality of service (QoS) provisioning in WiMAX mesh
networks. QoS has become an attractive area of study driven by the increasing demand
for multimedia content delivered wirelessly. To accommodate the different applications,
the IEEE 802.16 standard defines four classes of service. In this dissertation, we propose a
comprehensive scheme consisting of routing, link scheduling, call admission control (CAC)
and channel assignment that considers all classes of service. Much of the work in the
literature considers each of these problems in isolation. Our routing schemes use a metric
that combines interference and traffic load to compute routes for requests while our link
scheduling ensures that the QoS requirements of admitted requests are strictly met. Results
from our simulation indicate that our routing and link scheduling schemes significantly
improve network performance when the network is congested.ix, 77 leaves : ill. ; 29 cm
2
Nagarajan, Krishnamurthy. "New resource allocation strategies based on statistical network traffic models". Diss., Georgia Institute of Technology, 2000. http://hdl.handle.net/1853/33437.
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Akkarajitsakul, Khajonpong. "Game theoretic models for multiple access and resource allocation in wireless networks". IEEE, 2009. http://hdl.handle.net/1993/8900.
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We first present a non-cooperative auction game to solve the bandwidth allocation problem for non-cooperative channel access in a wireless network. The Nash equilibrium is obtained as a solution of the game. To address this problem of bandwidth sharing under unknown information, we further develop a Bayesian auction game model and then Bayesian Nash equilibrium is then obtained. Next, we present a framework based on coalitional game for cooperative channel access for carry-and-forward-based data delivery. Each mobile node helps others to carry and then forward their data. A coalitional game is proposed to find a stable coalition structure for this cooperative data delivery. We next present static and dynamic coalitional games for carry-and-forward-based data delivery when the behavior of each mobile node is unknown by others. In the dynamic game, each mobile node can update its beliefs about other mobile nodes’ types when the static coalitional game is played repeatedly.
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El, Houmaidi Mounire. "RESOURCE ALLOCATION SCHEMES AND PERFORMANCE EVALUATION MODELS FOR WAVELENGTH DIVISION MULTIPLEXED OPTICAL NETWORKS". Doctoral diss., University of Central Florida, 2005. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/4331.
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Wavelength division multiplexed (WDM) optical networks are rapidly becoming the technology of choice in network infrastructure and next-generation Internet architectures. WDM networks have the potential to provide unprecedented bandwidth, reduce processing cost, achieve protocol transparency, and enable efficient failure handling. This dissertation addresses the important issues of improving the performance and enhancing the reliability of WDM networks as well as modeling and evaluating the performance of these networks. Optical wavelength conversion is one of the emerging WDM enabling technologies that can significantly improve bandwidth utilization in optical networks. A new approach for the sparse placement of full wavelength converters based on the concept of the k-Dominating Set (k-DS) of a graph is presented. The k-DS approach is also extended to the case of limited conversion capability using three scalable and cost-effective switch designs: flexible node-sharing, strict node-sharing and static mapping. Compared to full search algorithms previously proposed in the literature, the K-DS approach has better blocking performance, has better time complexity and avoids the local minimum problem. The performance benefit of the K-DS approach is demonstrated by extensive simulation. Fiber delay line (FDL) is another emerging WDM technology that can be used to obtain limited optical buffering capability. A placement algorithm, k-WDS, for the sparse placement of FDLs at a set of selected nodes in Optical Burst Switching (OBS) networks is proposed. The algorithm can handle both uniform and non-uniform traffic patterns. Extensive performance tests have shown that k-WDS provides more efficient placement of optical fiber delay lines than the well-known approach of placing the resources at nodes with the highest experienced burst loss. Performance results that compare the benefit of using FDLs versus using optical wavelength converters (OWCs) are presented. A new algorithm, A-WDS, for the placement of an arbitrary numbers of FDLs and OWCs is introduced and is evaluated under different non-uniform traffic loads. This dissertation also introduces a new cost-effective optical switch design using FDL and a QoS-enhanced JET (just enough time) protocol suitable for optical burst switched WDM networks. The enhanced JET protocol allows classes of traffic to benefit from FDLs and OWCs while minimizing the end-to-end delay for high priority bursts. Performance evaluation models of WDM networks represent an important research area that has received increased attention. A new analytical model that captures link dependencies in all-optical WDM networks under uniform traffic is presented. The model enables the estimation of connection blocking probabilities more accurately than previously possible. The basic formula of the dependency between two links in this model reflects their degree of adjacency, the degree of connectivity of the nodes composing them and their carried traffic. The usefulness of the model is illustrated by applying it to the sparse wavelength converters placement problem in WDM networks. A lightpath containing converters is divided into smaller sub-paths such that each sub-path is a wavelength continuous path and the nodes shared between these sub-paths are full wavelength conversion capable. The blocking probability of the entire path is obtained by computing the blocking probabilities of the individual sub-paths. The analytical-based sparse placement algorithm is validated by comparing it with its simulation-based counterpart using a number of network topologies. Rapid recovery from failure and high levels of reliability are extremely important in WDM networks. A new Fault Tolerant Path Protection scheme, FTPP, for WDM mesh networks based on the alarming state of network nodes and links is introduced. The results of extensive simulation tests show that FTPP outperforms known path protection schemes in terms of loss of service ratio and network throughput. The simulation tests used a wide range of values for the load intensity, the failure arrival rate and the failure holding time. The FTPP scheme is next extended to the differentiated services model and its connection blocking performance is evaluated. Finally, a QoS-enhanced FTPP (QEFTPP) routing and path protection scheme in WDM networks is presented. QEFTPP uses preemption to minimize the connection blocking percentage for high priority traffic. Extensive simulation results have shown that QEFTPP achieves a clear QoS differentiation among the traffic classes and provides a good overall network performance.Ph.D.
School of Computer Science
Engineering and Computer Science
Computer Science
5
Rashid, Mohammad Mamunur. "Radio resource allocation in emerging broadband wireless access networks : some analytical models and their applications". Thesis, University of British Columbia, 2010. http://hdl.handle.net/2429/23475.
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New generation wireless networks are designed not only to carry voice but also to support data-intensive and multimedia applications. Broadband wireless networks offer high bandwidth necessary to support these applications. However, without proper resource allocation schemes, increased bandwidth is not sufficient to meet diverse application quality of service (QoS) requirements. In designing or deploying a resource allocation scheme, it is crucial to understand the inter-relationship of the resource allocation scheme and important system parameters with resulting QoS performance. Analytical models provide an opportunity to derive these relationships in an accurate and readily verifiable way.
In this thesis, we develop novel analytical models for radio resource allocation schemes in emerging broadband wireless access networks. These models are then adopted for in-depth analysis of QoS performance of the modeled schemes and in devising new solutions based on the models to either improve upon or complement those schemes. Our work primarily deals with Medium Access Control layer; however, in most of our contributions, we also consider cross-layer issues. First, we develop a queueing model for a downlink packet scheduling policy in IEEE 802.16e mobile broadband systems and propose a resource allocation framework based on this model. Compared to existing schemes, proposed framework offers a simple yet more effective way to provide QoS to a heterogeneous mix of applications. Second, we develop a cross-layer model for a prominent multiuser scheduling scheme in multi-antenna-based broadband cellular systems. It captures cross-layer effects of important parameters of the multi-antenna physical layer. The model output is shown to have important applications in QoS provisioning. Next, we perform queueing analysis of controlled channel access mechanism in IEEE 802.11e-based Wireless Local Area Networks. Using the insight gained, we propose a novel channel access scheduling mechanism that achieves very robust performance in meeting QoS guarantees. Finally, we focus on a promising new technology called Cognitive Radio (CR), which can greatly improve spectrum utilization in next generation broadband systems. We develop a queueing model to analyze the performance of an opportunistic spectrum access mechanism in CR networks. The model has important applications including cross-layer analysis and admission control in CR-based broadband networks.
6
Nordai, Frederick Leon. "Balanced, capacitated, location-allocation problems on networks with a continuum of demand". Diss., Virginia Polytechnic Institute and State University, 1985. http://hdl.handle.net/10919/54313.
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Location-allocation problems can be described generically as follows: Given the location or distribution (perhaps, probabilistic) of a set of customers and their associated demands for a given product or service, determine the optimum location of a number of service facilities and the allocation of products or services from facilities to customers, so as to minimize total (expected) location and transportation costs.
This study is concerned with a particular subclass of location-allocation problems involving capacitated facilities and a continuum of demand. Specifically, two minisum, network-based location-allocation problems are analyzed in which facilities having known finite capacities are to be located so as to optimally supply/serve a known continuum of demand.
The first problem considered herein, is an absolute p-median problem in which p > l capacitated facilities are to be located on a chain graph having both nodal and link demands, the latter of which are defined by nonnegative, integrable demand functions. In addition, the problem is balanced, in that it is assumed the total demand equals the total supply. An exact solution procedure is developed, wherein the optimality of a certain location-allocation scheme (for any given ordering of the facilities) is used to effect a branch and bound approach by which one can identify an optimal solution to the problem.
Results from the chain graph analysis are then used to develop an algorithm with which one can solve a dynamic, sequential location-allocation problem in which a single facility per period is required to be located on the chain.
Finally, an exact solution procedure is developed for locating a capacitated, absolute 2-median on a tree graph having both nodal and link demands and for which the total demand is again equal to the total supply. This procedure utilizes an algorithm to construct two subtrees, each of whose ends constitute a set of candidate optimal locations for one of the two elements of an absolute 2-median. Additional localization results are used to further reduce the number of candidate pairs (of ends) that need to be considered, and then a post-localization analysis provides efficient methods of comparing the relative costs of the remaining pairs.Ph. D.
7
Zabanoot, Zaid Ahmed Said. "Modelling and Analysis of Resource Management Schemes in Wireless Networks. Analytical Models and Performance Evaluation of Handoff Schemes and Resource Re-Allocation in Homogeneous and Heterogeneous Wireless Cellular Networks". Thesis, University of Bradford, 2011. http://hdl.handle.net/10454/5383.
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Over recent years, wireless communication systems have been experiencing a dramatic and continuous growth in the number of subscribers, thus placing extra demands on system capacity. At the same time, keeping Quality of Service (QoS) at an acceptable level is a critical concern and a challenge to the wireless network designer. In this sense, performance analysis must be the first step in designing or improving a network. Thus, powerful mathematical tools for analysing most of the performance metrics in the network are required. A good modelling and analysis of the wireless cellular networks will lead to a high level of QoS. In this thesis, different analytical models of various handoff schemes and resource re-allocation in homogeneous and heterogeneous wireless cellular networks are developed and investigated. The sustained increase in users and the request for advanced services are some of the key motivations for considering the designing of Hierarchical Cellular Networks (HCN). In this type of system, calls can be blocked in a microcell flow over to an overlay macrocell. Microcells in the HCN can be replaced by WLANs as this can provide high bandwidth and its users have limited mobility features. Efficient sharing of resources between wireless cellular networks and WLANs will improve the capacity as well as QoS metrics. This thesis first presents an analytical model for priority handoff mechanisms, where new calls and handoff calls are captured by two different traffic arrival processes, respectively. Using this analytical model, the optimised number of channels assigned to II handover calls, with the aim of minimising the drop probability under given network scenarios, has been investigated. Also, an analytical model of a network containing two cells has been developed to measure the different performance parameters for each of the cells in the network, as well as altogether as one network system. Secondly, a new solution is proposed to manage the bandwidth and re-allocate it in a proper way to maintain the QoS for all types of calls. Thirdly, performance models for microcells and macrocells in hierarchical cellular networks have been developed by using a combination of different handoff schemes. Finally, the microcell in HCN is replaced by WLANs and a prioritised vertical handoff scheme in an integrated UMTS/WLAN network has been developed. Simulation experiments have been conducted to validate the accuracy of these analytical models. The models have then been used to investigate the performance of the networks under different scenarios.
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HE, FUJUN. "Reliable Resource Allocation Models in Network Virtualization". Doctoral thesis, Kyoto University, 2020. http://hdl.handle.net/2433/259077.
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京都大学0048
新制・課程博士
博士(情報学)
甲第22809号
情博第739号
新制||情||126(附属図書館)
京都大学大学院情報学研究科通信情報システム専攻
(主査)教授 大木 英司, 教授 守倉 正博, 教授 原田 博司
学位規則第4条第1項該当
Doctor of Informatics
Kyoto University
DFAM
9
Shrinivas, V. Prasanna. "Pricing Multicast Network Services". Thesis, Indian Institute of Science, 2001. http://hdl.handle.net/2005/270.
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Multicast has long been considered an attractive service for the Internet for the provision of multiparty applications. For over a decade now multicast has been a proposed IETF standard. Though there is a strong industry push towards deploying multicast, there has been little multicast deployment by commercial Internet Service Providers (ISPs) and more importantly most end-users still lack multicast capabilities. Depending on the underlying network infrastructure, the ISP has several options of implementing his multicast capabilities. With significantly faster and more sophisticated protocols being designed and prototyped, it is expected that a whole new gamut of applications that are delay sensitive will come into being. However, the incentives to resolve the conflicting interests of the ISPs and the end-users have to be provided for successful implementation of these protocols. Thus we arrive at the following economic questions: What is the strategy that will enable the ISP recover his costs ? How can the end-user be made aware of the cost of his actions ? Naturally, the strategies of the ISP and the end-user depend on each other and form an economic game. The research problems addressed in this thesis are:
A pricing model that is independent of the underlying transmission protocols is prefered. We have proposed such a pricing scheme for multicast independent of the underlying protocols, by introducing the concept of pricing points* These pricing points provide a range of prices that the users can expect during a particular time period and tune their usage accordingly. Our pricing scheme makes both the sender and receiver accountable. Our scheme also provides for catering to heterogeneous users and gives incentive for differential pricing.
We explore a number of formulations of resource allocation problems arising in communication networks as optimization models. Optimization-based methods were only employed for unicast congestion control. We have extended this method for single rate multicast. We have also devised an optimization-based approach for multicast congestion control that finds an allocation rate to maximize the social welfare. Finally we also show that the session-splitting problem can also be cast as an optimization problem.
The commonly used "max-min" fairness criteria suffers from serious limitations like discriminating sessions that traverse large number of links and poor network utilization. We provide an allocation scheme that reduces discrimination towards multicast sessions that traverse many links and also improves network utilization.
10
Benincasa, Stefano. "Evolutionary Behavioral Economics: Essays on Adaptive Rationality in Complex Environments". Doctoral thesis, Università degli studi di Trento, 2020. http://hdl.handle.net/11572/268752.
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Against the theoretical background of evolutionary behavioral economics, this project analyzes bounded rationality and adaptive behaviour in organizational settings characterized by complexity and persistent uncertainty. In particular, drawing upon the standard NK model, two laboratory experiments investigate individual and collective decision-making in combinatorial problems of resource allocation featuring multiple dimensions and various levels of complexity. In the first study, investment horizons of different length are employed to induce a near or distant future temporal orientation, in order to assess the effects of complexity and time horizon on performance and search behaviour, examine the presence of a temporal midpoint heuristic, and inspect the moderating effects of deadline proximity on the performance-risk relationship. This is relevant for organizational science because the passage of time is essential to articulate many strategic practices, such as assessing progress, scheduling and coordinating task-related activities, discerning the processual dynamics of how these activities emerge, develop, and terminate, or interpreting retrospected, current, and anticipated events. A greater or lesser amount of time reflects then a greater or lesser provision of resources, thereby representing a constraint that can greatly affect the ability to maintain a competitive advantage or ensure organizational survival. In the second study, the accuracy of the imitative process is varied to induce a flawless or flawed information diffusion system and, congruently, an efficient or inefficient communication network, in order to assess the effects of complexity and parallel problem-solving on autonomous search behaviour, clarify the core drivers of imitative behaviour, control for the degree of strategic diversity under different communication networks, and evaluate individual as well as collective performance conditional to the interaction between the levels of complexity and the modalities of parallel problem-solving. This is relevant for organizational science because imitating the practices of high-performing actors is one of the key strategies employed by organizations to solve complex problems and improve their performance, thereby representing a major part of the competitive process. The project is intended to contribute grounding individual and collective behaviour in a more psychologically and socially informed decision-making, with a view to further the research agenda of behavioral strategy and sustain the paradigm shift towards an evolutionary-complexity approach to real economic structures.
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Li, Guoqing. "Resource allocation in OFDMA networks /". Thesis, Connect to this title online; UW restricted, 2004. http://hdl.handle.net/1773/6136.
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Eriksson, Kristoffer. "Dynamic Resource Allocation in Wireless Networks". Thesis, Linköping University, Communication Systems, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-56776.
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In this thesis we investigate different algorithms for dynamic resource allocation in wireless networks. We introduce a general framework for modeling systems whichis applicable to many scenarios. We also analyze a specific scenario with adaptivebeamforming and show how it fits into the proposed framework. We then studytwo different resource allocation problems: Quality-of-Service (QoS) constraineduser scheduling and sum-rate maximization. For user scheduling, we select some“good” set of users that is allowed to use a specific resource. We investigatedifferent algorithms with varying complexities. For the sum-rate maximizationwe find the global optimum through an algorithm that takes advantage of thestructure of the problem by reformulating it as a D.C. program, i.e., a minimizationover a difference of convex functions. We validate this approach by showing that itis more efficient than an exhaustive search at exploring the space of solutions. Thealgorithm provides a good benchmark for more suboptimal algorithms to comparewith. The framework in which we construct the algorithm, apart from being verygeneral, is also very flexible and can be used to implement other low complexitybut suboptimal algorithms.
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Farrokh, Arsalan. "Stochastic resource allocation in wireless networks". Thesis, University of British Columbia, 2007. http://hdl.handle.net/2429/31303.
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This thesis presents several efficient and adaptive resource allocation schemes in wireless networks under the framework of Markov Decision Problem (MDP). In particular, we formulate meaningful trade-offs for three specific resource allocation problems as MDPs and show that their solutions exhibit certain special structures. In each case, by utilizing the underlying structure, we present a resource allocation solution that is computationally inexpensive and is scalable in terms of the system parameters. First, we present opportunistic algorithms in scheduling High Speed Downlink Packet Access (HSDPA) users that exploit channel and buffer variations to increase the probability of uninterrupted media play-out. We formulate a feasibility problem with stability and robustness Quality-of-Service (QoS) constraints. A methodology for obtaining a feasible solution is proposed by starting with a stable algorithm that satisfies the stability QoS constraints. Next, we present optimal adaptive modulation and coding policies that minimize the transmission latency and modulation/coding switching cost across finite-state Markovian fading channels. The optimal tradeoff between the transmission delay and the switching costs is formulated as a discounted cost infinite horizon MDP. We show that under certain sufficient conditions optimal modulation and coding selection policies are monotone in the state variables. Finally, we present an ARQ-based power and retransmission control policy that achieves an optimal tradeoff between transmission power, delay, and packet drop penalty costs. Under certain sufficient conditions, we show that the optimal power and retransmission control policies are monotone in the channel quality, the penalty cost, and the number of the retransmission slots left.Applied Science, Faculty of
Electrical and Computer Engineering, Department of
Graduate
14
Thanabalasingham, Thayaparan. "Resource allocation in OFDM cellular networks /". Connect to thesis, 2006. http://eprints.unimelb.edu.au/archive/00003227.
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Sun, Fanglei y 孫芳蕾. "Resource allocation in broadband wireless networks". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2008. http://hub.hku.hk/bib/B40887868.
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Zhou, Jihai. "Resource allocation in ad hoc networks". Thesis, Imperial College London, 2011. http://hdl.handle.net/10044/1/6928.
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Unlike the centralized network, the ad hoc network does not have any central administrations and energy is constrained, e.g. battery, so the resource allocation plays a very important role in efficiently managing the limited energy in ad hoc networks. This thesis focuses on the resource allocation in ad hoc networks and aims to develop novel techniques that will improve the network performance from different network layers, such as the physical layer, Medium Access Control (MAC) layer and network layer. This thesis examines the energy utilization in High Speed Downlink Packet Access (HSDPA) systems at the physical layer. Two resource allocation techniques, known as channel adaptive HSDPA and two-group HSDPA, are developed to improve the performance of an ad hoc radio system through reducing the residual energy, which in turn, should improve the data rate in HSDPA systems. The channel adaptive HSDPA removes the constraint on the number of channels used for transmissions. The two-group allocation minimizes the residual energy in HSDPA systems and therefore enhances the physical data rates in transmissions due to adaptive modulations. These proposed approaches provide better data rate than rates achieved with the current HSDPA type of algorithm. By considering both physical transmission power and data rates for defining the cost function of the routing scheme, an energy-aware routing scheme is proposed in order to find the routing path with the least energy consumption. By focusing on the routing paths with low energy consumption, computational complexity is significantly reduced. The data rate enhancement achieved by two-group resource allocation further reduces the required amount of energy per bit for each path. With a novel load balancing technique, the information bits can be allocated to each path in such that a way the overall amount of energy consumed is minimized. After loading bits to multiple routing paths, an end-to-end delay minimization solution along a routing path is developed through studying MAC distributed coordination function (DCF) service time. Furthermore, the overhead effect and the related throughput reduction are studied. In order to enhance the network throughput at the MAC layer, two MAC DCF-based adaptive payload allocation approaches are developed through introducing Lagrange optimization and studying equal data transmission period.
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Sun, Fanglei. "Resource allocation in broadband wireless networks". Click to view the E-thesis via HKUTO, 2008. http://sunzi.lib.hku.hk/hkuto/record/B40887868.
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Liu, Lingjia. "On delay-sensitive communication over wireless systems". [College Station, Tex. : Texas A&M University, 2008. http://hdl.handle.net/1969.1/ETD-TAMU-2725.
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Li, Cai. "Simulator for Resource Allocation in Hybrid Networks". Thesis, Linköping University, Department of Computer and Information Science, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-2808.
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Much work has been done in simulating traditional cellular networks. But with the incoming of ad-hoc network technology, the next generation networks will employ hybrid network architectures using both cellular and ad-hoc networking concepts.
We investigate how to create a simulator being able to simulate a hybrid wireless network. This involves setting up a cellular network and an ad-hoc network respectively. However, the most important thing is how to integrate them seamlessly.
Fortunately, there has already been a simulator called SIMRA which simulates a UMTS cellular network. Therefore, this thesis work is greatly simplified as how to extend and improve SIMRA to implement a simulator for hybrid wireless network. We selected J-sim as the developing platform for our simulator and our development was greatly based on the wireless package provided by the latest version of J-sim.
To evaluate the new simulator, different resource allocation algorithms were run against it and the results were compared to those generated by earlier extensions to SIMRA under the same simulation settings. It showed that the resource allocation algorithms behaved similarly under the hybrid wireless network environment. Nevertheless, there are some discrepancies in behaviors of algorithms used for evaluation that still need to be studied.
20
Wong, Chung Kit. "Resource allocation for multihop packet radio networks". Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68059.
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This thesis focuses on the routing, power control and channel allocation of Packet Radio Network (PRnet) with multiple channels. The Nearest Forward with Progress (NFP) routing policy is known to achieve higher throughput in the single channel setting than the Most Forward with Progress (MFP) strategy. This observation motivates our work on the variant of the Shacham/King model in which MFR is replaced by NFP in a multi-channel case. The resulting network shows that the superiority of NFP relative to MFP persists. Another way to improve network performance is to control the network topology by restricting the set of possible paths. Pairwise Channel Assignment (PCA), which assigns the different channels to the restricted paths, is modified so as to expand its applicability and reduce its computational burden without significant loss of throughput. The performance evaluations are based on a combination of analysis and simulation.
21
Usaha, Wipawee. "Resource allocation in networks with dynamic topology". Thesis, Imperial College London, 2004. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.405658.
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Pan, Yuwen. "Resource allocation in OFDMA-based relaying networks". Thesis, University of Bristol, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.529829.
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Zhou, Haojie y 周豪杰. "Auction-based resource allocation in selfish networks". Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2014. http://hdl.handle.net/10722/206758.
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Networks function properly only when nodes cooperate to provide service. In many networks, such as ad hoc and interdomain networks, network devices are deployed by different owners. Due to limited communication resources, nodes in such networks may behave selfishly. That is, they are only interested in maximizing their own utilities, leading to selfish networks. Incentives are required in such networks to stimulate cooperation. In wired selfish networks, existing work mainly focuses on traffic assignment among predetermined available paths for one source and destination pair. In wireless selfish networks, available bandwidth is assumed to be fixed and predetermined, and the interferences among flows are ignored. Resource allocation in selfish networks needs to be developed under more general models. This dissertation has devised general analytical models for bandwidth allocation in wired and wireless selfish networks. Based on the analogy between resource allocation in selfish networks and auction, auction theory has been adopted in the design and analysis of resource allocation schemes. With incentives introduced in the schemes, selfish nodes will follow the prescribed algorithm and report their information truthfully so that the system cost is minimized.
I firstly propose a general model for bandwidth allocation in wired selfish networks. Bandwidth requirements of call routing requests in a given period are allocated as a batch and satisfied at the end of the period. Then, a centralized mechanism is designed to allocate bandwidth and determine payments with different sequencing strategies. Some properties of the mechanism such as individual rationality and incentive-compatibility are studied.
I go on to develop the distributed algorithm in wired selfish networks. Available paths are no longer assumed to be fixed and predetermined. Destination nodes conduct the sub-auctions in a certain order for bandwidth allocation and determine payments in a distributed manner. Truthfulness of the distributed mechanism is guaranteed under Nash equilibrium. This distributed mechanism, as a more scalable solution to allocate bandwidth in wired selfish networks, can still guarantee the performance achieved by existing work.published_or_final_version
Electrical and Electronic Engineering
Doctoral
Doctor of Philosophy
24
Blasco, Moreno Pol. "Learning-based resource allocation in wireless networks". Thesis, Imperial College London, 2014. http://hdl.handle.net/10044/1/23295.
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This thesis investigates learning-based resource allocation techniques for future wireless networks (FWNs). Motivated by recent technological developments, two types of FWNs are studied: energy harvesting (EH) wireless sensor networks (WSNs), and high-capacity cellular networks (HC-CNs) with caching capabilities. In an EH-WSN, each node is powered by a rechargeable battery and harvests energy from the environment. First, a multi-access throughput optimisation problem is studied, when the access point schedules EH sensor nodes without the knowledge of their battery states. A low-complexity policy is shown to be optimal in certain cases, and a scheduling algorithm, which takes into account the random processes governing the energy arrivals in the system, is proposed, and compared to an upper bound. Second, a point-to-point communication system with an EH transmitter is considered. Since the characteristics of the environment in which the sensor will be deployed are not known in advance, we assume no a priori knowledge of the random processes governing the system, and propose a learning theoretic optimisation for the system operation. The performance of the proposed algorithm is compared to that of two upper bounds, obtained by providing more information to the transmitter about the random processes governing the system. We then turn our attention to content-level selective offloading to an infostation terminal in an HC-CN. The infostation, which stores high data-rate content in its cache memory, allows cellular users in the vicinity to directly download the stored content through a broadband connection, reducing the latency and the load on the cellular network. The goal of the infostation cache controller is to store the most popular content such that the maximum amount of traffic is o oaded to the infostation. The optimal cache content management problem when content popularity is unknown is studied, and a number of algorithms to learn the content popularity pro le are proposed. The performances of these algorithms are compared to that of an informed upper bound, obtained when the content popularity pro le is known.
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Chen, Xuetao. "Resource Allocation for Wireless Distributed Computing Networks". Diss., Virginia Tech, 2012. http://hdl.handle.net/10919/77054.
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Wireless distributed computing networks (WDCNs) will become the next frontier of the wireless industry as the performance of wireless platforms is being increased every year and wireless industries are looking for "killer" applications for increased channel capacity. However, WDCNs have several unique problems compared with currently well-investigated methods for wireless sensor networks and wired distributed computing. For example, it is difficult for WDCNs to be power/energy efficient considering the uncertainty and heterogeneity of the wireless environment. In addition, the service model has to take account of the interference-limited feature of wireless channels to reduce the service delay.
Our research proposes a two-phase model for WDCNs including the service provision phase and the service access phase according to different traffic patterns and performance requirements. For the service provision phase, we investigate the impact of communication channel conditions on the average execution time of the computing tasks within WDCNs. We then discuses how to increase the robustness and power efficiency for WDCNs subject to the impact of channel variance and spatial heterogeneity. A resource allocation solution for computation oriented WDCNs is then introduced in detail which mitigates the effects of channel variations with a stochastic programming solution.
Stochastic geometry and queue theory are combined to analyze the average performance of service response time and to design optimal access strategies during the service access phase. This access model provides a framework to analyze the service access performance and evaluate whether the channel heterogeneity should be considered. Based on this analysis, optimal strategies to access the service nodes can be determined in order to reduce the service response time. In addition, network initialization and synchronization are investigated in order to build a multiple channel WDCN in dynamic spectrum access (DSA) environments. Further, an efficient primary user detection method is proposed to reduce the channel vacation latency for WDCNs in DSA environments.
Finally, this dissertation presents the complete design and implementation of a WDCN on COgnitive Radio Network (CORNET). Based on SDR technologies, software dedicated to WDCNs is designed and implemented across the PHY layer, MAC layer, and application layer. System experiments are carried out to demonstrate the performance issues and solutions presented in this dissertation. Wireless distributed computing networks (WDCNs) will become the next frontier of the wireless industry as the performance of wireless platforms is being increased every year and wireless industries are looking for "killer" applications for increased channel capacity. However, WDCNs have several unique problems compared with currently well-investigated methods for wireless sensor networks and wired distributed computing. For example, it is difficult for WDCNs to be power/energy efficient considering the uncertainty and heterogeneity of the wireless environment. In addition, the service model has to take account of the interference-limited feature of wireless channels to reduce the service delay.
Our research proposes a two-phase model for WDCNs including the service provision phase and the service access phase according to different traffic patterns and performance requirements. For the service provision phase, we investigate the impact of communication channel conditions on the average execution time of the computing tasks within WDCNs. We then discuses how to increase the robustness and power efficiency for WDCNs subject to the impact of channel variance and spatial heterogeneity. A resource allocation solution for computation oriented WDCNs is then introduced in detail which mitigates the effects of channel variations with a stochastic programming solution.
Stochastic geometry and queue theory are combined to analyze the average performance of service response time and to design optimal access strategies during the service access phase. This access model provides a framework to analyze the service access performance and evaluate whether the channel heterogeneity should be considered. Based on this analysis, optimal strategies to access the service nodes can be determined in order to reduce the service response time. In addition, network initialization and synchronization are investigated in order to build a multiple channel WDCN in dynamic spectrum access (DSA) environments. Further, an efficient primary user detection method is proposed to reduce the channel vacation latency for WDCNs in DSA environments.
Finally, this dissertation presents the complete design and implementation of a WDCN on COgnitive Radio Network (CORNET). Based on SDR technologies, software dedicated to WDCNs is designed and implemented across the PHY layer, MAC layer, and application layer. System experiments are carried out to demonstrate the performance issues and solutions presented in this dissertation.Ph. D.
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Aliu, Osianoh Glenn. "Resource allocation in self organising cellular networks". Thesis, University of Surrey, 2012. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.580334.
Texto completoResumen
With the surge in smartphones and tablets, the future of wireless cellular communication systems is marked by a drastic change in user behaviour triggered by the unbridled growth of bandwidth hungry applications. This challenge as well as the limited spectral resources drives the need to further improve resource allocation schemes for cellular networks. This thesis focuses on resource allocation in self organised cellular networks. A distributed self organised channel assignment scheme has been proposed that is shown to achieve perfect orthogonality among neighbouring sectors and reveals the importance of localised rules in designing distributed self organised systems. We define a sectorial neighbourhood based on intercell interference consideration and apply a local coordination among these sectors to achieve a self organised assignment. This unique solution for spectrum assignment strategy is demonstrated as a dynamic spectrum allocation scheme as well as a combination of both the dynamic and static spectrum allocation schemes, verified by system level simulations. The marked improvement in system performance is however not evident for users located at cell edges. Due to the performance of these cell edge users, a self organised fractional frequency reuse scheme whose allocation adapts to the system dynamics is proposed. Current solutions that employ a Fractional Frequency Reuse (FFR) are first analysed to challenge the assumption of fixed cell edge region and power allocation irrespective of the unique user distribution in each cell and its neighbours. We define a unique property for each sector based on its user distribution called its Centre of Gravity (CoG). With the CoG, each sector is classified into states that enables us to apply cellular automata theory that results in a self organised fractional frequency reuse scheme. For mulithop communication links however, intercell interference analysis becomes more complicated due to interference introduced by relay nodes. We finally investigate FFR schemes in multihop communication links comparing the performance of existing FFR schemes in multihop links in terms of their spectral efficiency and area spectral efficiency. A new FFR scheme specifically tailored for multihop links is thus proposed by applying a reuse scheme both in the cell centre and edge regions but rotated at an angle of 1200 in the centre region. Furthermore, the sectorial neighbourhood principle introduced earlier is further applied to ensure intercell interference is further minimised.
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Owens, II Harold. "Resource Allocation in Mobile and Wireless Networks". Thesis, University of North Texas, 2003. https://digital.library.unt.edu/ark:/67531/metadc4256/.
Texto completoResumen
The resources (memory, power and bandwidth) are limited in wireless and mobile networks. Previous research has shown that the quality of service (QoS) of the mobile client can be improved through efficient resources management. This thesis contains two areas of research that are strongly interrelated. In the first area of research, we extended the MoSync Algorithm, a network application layer media synchronization algorithm, to allow play-out of multimedia packets by the base station upon the mobile client in a First-In-First-Out (FIFO), Highest-Priority-First (PQ), Weighted Fair-Queuing (WFQ) and Round-Robin (RR) order. In the second area of research, we make modifications to the DSR and TORA routing algorithms to make them energy aware routing protocols. Our research shows that the QoS of the mobile client can be drastically improved through effective resource allocation.
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Tychogiorgos, Georgios. "Non-convex resource allocation in communication networks". Thesis, Imperial College London, 2013. http://hdl.handle.net/10044/1/14710.
Texto completoResumen
The continuously growing number of applications competing for resources in current communication networks highlights the necessity for efficient resource allocation mechanisms to maximize user satisfaction. Optimization Theory can provide the necessary tools to develop such mechanisms that will allocate network resources optimally and fairly among users. However, the resource allocation problem in current networks has characteristics that turn the respective optimization problem into a non-convex one. First, current networks very often consist of a number of wireless links, whose capacity is not constant but follows Shannon capacity formula, which is a non-convex function. Second, the majority of the traffic in current networks is generated by multimedia applications, which are non-concave functions of rate. Third, current resource allocation methods follow the (bandwidth) proportional fairness policy, which when applied to networks shared by both concave and non-concave utilities leads to unfair resource allocations. These characteristics make current convex optimization frameworks inefficient in several aspects. This work aims to develop a non-convex optimization framework that will be able to allocate resources efficiently for non-convex resource allocation formulations. Towards this goal, a necessary and sufficient condition for the convergence of any primal-dual optimization algorithm to the optimal solution is proven. The wide applicability of this condition makes this a fundamental contribution for Optimization Theory in general. A number of optimization formulations are proposed, cases where this condition is not met are analysed and efficient alternative heuristics are provided to handle these cases. Furthermore, a novel multi-sigmoidal utility shape is proposed to model user satisfaction for multi-tiered multimedia applications more accurately. The advantages of such non-convex utilities and their effect in the optimization process are thoroughly examined. Alternative allocation policies are also investigated with respect to their ability to allocate resources fairly and deal with the non-convexity of the resource allocation problem. Specifically, the advantages of using Utility Proportional Fairness as an allocation policy are examined with respect to the development of distributed algorithms, their convergence to the optimal solution and their ability to adapt to the Quality of Service requirements of each application.
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Ngo, Duy. "Radio resource allocation for wireless heterogeneous networks". Thesis, McGill University, 2013. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=119622.
Texto completoResumen
By deploying small cells (i.e., femtocells) within the same service area of regular macrocells, a much higher area spectral efficiency, better indoor coverage, and significant mobile data offloading can be achieved at low cost. Because femtocells reuse the radio spectrum already assigned to macrocells in an uncoordinated fashion, new cell boundaries are created and the signal interference situation becomes far more unpredictable than in conventional networks. In this heterogeneous network setting, adaptive power allocation and dynamic spectrum access are needed to ensure a harmonized coexistence of network entities with diverse design specifications. Since femtocells are deployed by end users without any network planning, autonomous solutions are desirable to effectively control the severe intra-tier and cross-tier interferences. In this study, we develop and evaluate distributed radio resource allocation algorithms for wireless heterogeneous networks employing code-division multiple access (CDMA) and orthogonal frequency division multiple access (OFDMA). Requiring no central coordination, the devised solutions robustly protect the ongoing operation of all existing macrocell users, while optimally exploiting the residual network capacity for femtocells. In CDMA-based networks, we propose a dynamic pricing scheme combined with femtocell user admission control to indirectly manage the cross-tier interference. The proposed joint power and admission control algorithms can be locally executed at each link to offer a maximum utility to individual users. For the total network utility maximization, we develop joint Pareto-optimal power control and signal-to-interference-plus-noise ratio (SINR) assignment algorithms that can fairly share radio resources among users. Upon applying convex optimization methods, the minimum SINRs prescribed by macrocell users are effectively enforced, whereas the sum network utility is globally maximized. In OFDMA-based networks, to resolve the highly nonconvex and combinatorial problem of joint power and subchannel allocation, we propose a dynamic spectrum management scheme that alternatively optimizes the powers and assigns the subchannels. With the adopted successive convex approximation approach, the total throughput of all femtocells is maximized whilst the macrocell network capacity is always protected. In cognitive femtocells where femtocell users opportunistically access the spectrum licensed to macrocells, we apply Lagrangian duality to devise jointly optimal power and subchannel allocation algorithms. The distributed solutions are shown to achieve their global optimality with low complexity.En déployant de petites cellules (dénommées les femtocells) au sein de la même zone de service que les cellules de tailles régulières (dénommées cellules macro), une efficacité spectrale zone beaucoup plus élevé, une meilleure couverture à l'intérieur, et d'importantes données mobiles de déchargement entre les deux cellules peuvent être réalisé tout en gardant faible coût. Vu que les femtocells réutilisent le spectre de fréquence déjà consacré à la cellule macro, auxquelles ils sont assignés, d'une manière non-coordonnée, de nouvelles limites de cellules sont créées et l'interférence devient beaucoup plus imprévisible que dans les réseaux traditionnels. Dans ce contexte réseau hétérogène, une allocation adaptative de puissance et des méthodes d'accès dynamiques au spectre sont nécessaires pour assurer une coexistence harmonisée des entités du réseau avec les nouvelles spécifications imposées par les femtocells. Depuis que les femtocells sont déployées par les terminaux sans aucune planification au préalable du réseau, des solutions qui s'adaptent automatiquement sont toujours désirable pour contrôler efficacement les sévères interférences entre les différents niveaux du réseau sans fil hétérogène.Dans cette étude, nous développons et évaluons des algorithmes distribués pour l'allocation de ressources radio dans les réseaux sans fil hétérogènes employant l accès multiple par répartition en code (CDMA) et Accès multiple par répartition en fréquence (OFDMA). En évitant une coordination centralisée, les solutions proposées protègent le fonctionnement de tous les utilisateurs de la cellule macro existantes, tout en exploitant de manière optimale la capacité résiduelle du réseau pour les utilisateurs du femtocells. Dans les réseaux CDMA, nous proposons un schéma de tarification dynamique associé à un contrôle d'admission des utilisateurs de la femtocell nous permettant de gérer indirectement l'interférence inter-niveaux (entre cellule macro et femtocell). Le contrôle simultané de la puissance et les algorithmes de contrôle d'admission proposés peut être exécuté localement sur chaque lien pour offrir un maximum d'utilité pour les utilisateurs individuels. Pour maximiser l'utilité totale du réseau, nous développons un algorithme de contrôle simultané de puissance basant sur l'optimalité de Pareto et le rapport signal sur interférence plus bruit (SINR) qui peut partager équitablement les ressources radio entre les utilisateurs. En appliquant d'une méthode d'optimisation, les SINR minimaux prescrits par les utilisateurs des cellules macro sont garantis, alors que le maximal global la somme de l'utilité du réseau est trouvé.Dans les réseaux OFDMA, afin de résoudre le problème non convexe et combinatoire de l'allocation conjointe de la puissance et des sous-porteuses, nous proposons un schéma alternatif de gestion dynamique du spectre qui optimise la distribution de puissance et des sous-porteuses. Avec l'approche par approximations successives convexe adoptée, le débit total de tous les femtocells est maximisé alors que la capacité du réseau de la cellule macro est toujours protégée. En femtocells cognitives où les utilisateurs du femtocell accèdent au spectre autorisé à la cellule macro d'une manière opportuniste, nous appliquons la dualité lagrangienne pour optimiser la distribution de la puissance et des sous-porteuses. Nous prouvons que les solutions distribuées proposées atteignent leur optimal global avec une faible complexité.
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Jin, Xin. "Resource allocation in multicarrier cognitive radio networks". Thesis, Evry, Institut national des télécommunications, 2014. http://www.theses.fr/2014TELE0014/document.
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Vu que la modulation multi-porteuses est largement utilisée dans les communications sans fil et la radio cognitive (CR pour “Cognitive Radio”) améliore l’utilisation des ressources radio et du spectre, nous nous concentrons sur les réseaux radio cognitifs (CR) pour faire progresser l’allocation des ressources, le routage, et l’ajustement de la puissance d’émission vers les récepteurs (synthèse de faisceaux ou beamforming) dans cette thèse. Nous étudions deux types de modulations multi-porteuses :Orthogonal Frequency-Division Multiplexing (OFDM) à base d’ondelettes (WOFDM pourWavelet OFDM) et OFDM dans sa forme classique ou traditionnelle (OFDM s’appuyant sur la transformation de Fourier pour partager les ressources). WOFDM adopte Wavelet Packet Modulation (WPM) pour obtenir des lobes secondaires beaucoup plus faibles dans la densité spectrale de puissance du signal transmis en comparaison à OFDM. WPM permet de surcroit à WOFDM de s’affranchir du Préfixe Cyclique (indispensable à OFDM) et d’exploiter l’égalisation pour combattre l’Interférence entre Symboles (ISI). Nous évaluons la performance de WOFDM sous différentes conditions du canal radio. Nous comparons la performance de WOFDM, qui s’appuie sur l’égalisation dans le domaine temporel, à celle de OFDM, qui requiert l’utilisation du Préfixe Cyclique et opère dans le domaine fréquentielIn view of the wide usage of multicarrier modulation in wireless communications and the prominent contribution of Cognitive Radio (CR) to deal with critical shortage of spectrum resource, we focus on multicarrier based cognitive radio networks to investigate general resource allocation issues: subcarrier allocation, power allocation, routing, and beamforming in this thesis. We investigate two types of multicarrier modulation: Wavelet-based Orthogonal Frequency Division Multiplexing (WOFDM) and Fourier-based Orthogonal Frequency Division Multiplexing (OFDM). WOFDM adopts Wavelet Packet Modulation (WPM). Compared with fourier-based OFDM, wavelet-based OFDM achieves much lower side lobe in the transmitted signal. Wavelet-based OFDM excludes Cyclic Prefix (CP) which is used in fourier-based OFDM systems. Wavelet-based OFDM turns to exploit equalization to combat Inter-Symbol Interference (ISI). We evaluate the performance of WOFDM under different channel conditions. We compare the performance of wavelet-based OFDM using equalization in the time domain to that of fourier-based OFDM with CP and the equalization in the frequency domain
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Lopez, Guerrero Miguel. "On network resource allocation using alpha-stable long-range dependent traffic models". Thesis, University of Ottawa (Canada), 2004. http://hdl.handle.net/10393/29136.
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Recent studies suggest that networks should be designed taking into account the long-range dependence and high-variability properties of the traffic they carry. It has been proven in the past that these two statistical properties can be properly represented using traffic models based on alpha-stable self-similar stochastic processes. Assuming this traffic modeling approach, in this dissertation we propose and evaluate some techniques for resource allocation. We propose suitable envelope processes for the levels of bandwidth demand which allows us to develop static resource allocation schemes. The proposal is based on a generalization, to the alpha-stable case, of the concept of probabilistic envelope processes, which have been previously defined for simpler models. It is shown that, with this approach, we can simply and effectively deal with much of the argued complexity encountered in alpha-stable models and develop techniques for proper dimensioning of network elements. From our analysis it is concluded that the presence of heavy tails in the distribution of the traffic process has a severe impact on the requirements of network resource. For instance, the multiplexing gain is negatively affected, which directly impacts the scale economies expected by service providers. In order to cope with these issues, dynamic resource allocation is also considered. A dynamic prediction-based resource allocation method is introduced and evaluated. It is shown that it significantly improves network utilization over static resource allocation schemes in trade for some signaling and processing overhead. Although other schemes based on prediction have been proposed, we use a novel linear prediction algorithm for symmetric fractional stable noise. This approach is intended for some traffic classes whose marginal distribution exhibits a heavy tail. The linear prediction algorithm we use was recently introduced by other researchers, but has not been studied in detail. Therefore, its performance evaluation is also carried out. In addition to this study on the prediction-based approach, a dynamic resource allocation scheme based on envelope processes is also introduced and evaluated. We conclude that when alpha-stable models are properly used and interpreted, they let us accurately represent network traffic and therefore design and analyze reliable resource allocation mechanisms.
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Ranasingha, Maththondage Chamara Sisirawansha. "Towards a Framework For Resource Allocation in Networks". Scholarly Repository, 2009. http://scholarlyrepository.miami.edu/oa_dissertations/252.
Texto completoResumen
Network resources (such as bandwidth on a link) are not unlimited, and must be shared by all networked applications in some manner of fairness. This calls for the development and implementation of effective strategies that enable optimal utilization of these scarce network resources among the various applications that share the network. Although several rate controllers have been proposed in the literature to address the issue of optimal rate allocation, they do not appear to capture other factors that are of critical concern. For example, consider a battlefield data fusion application where a fusion center desires to allocate more bandwidth to incoming flows that are perceived to be more accurate and important. For these applications, network users should consider transmission rates of other users in the process of rate allocation. Hence, a rate controller should consider application specific rate coordination directives given by the underlying application. The work reported herein addresses this issue of how a rate controller may establish and maintain the desired application specific rate coordination directives. We identify three major challenges in meeting this objective. First, the application specific performance measures must be formulated as rate coordination directives. Second, it is necessary to incorporate these rate coordination directives into a rate controller. Of course, the resulting rate controller must co-exist with ordinary rate controllers, such as TCP Reno, in a shared network. Finally, a mechanism for identifying those flows that require the rate allocation directives must be put in place. The first challenge is addressed by means of a utility function which allows the performance of the underlying application to be maximized. The second challenge is addressed by utilizing the Network Utility Maximization (NUM) framework. The standard utility function (i.e. utility function of the standard rate controller) is augmented by inserting the application specific utility function as an additive term. Then the rate allocation problem is formulated as a constrained optimization problem, where the objective is to maximize the aggregate utility of the network. The gradient projection algorithm is used to solve the optimization problem. The resulting solution is formulated and implemented as a window update function. To address the final challenge we resort to a machine learning algorithm. We demonstrate how data features estimated utilizing only a fraction of the flow can be used as evidential input to a series of Bayesian Networks (BNs). We account for the uncertainty introduced by partial flow data through the Dempster-Shafer (DS) evidential reasoning framework.
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Kibria, Mirza Golam. "Radio Resource Allocation Optimization for Cellular Wireless Networks". 京都大学 (Kyoto University), 2014. http://hdl.handle.net/2433/189689.
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Tekbiyik, Ersoy Neyre. "Efficient Resource Allocation In Energy Harvesting Wireless Networks". Phd thesis, METU, 2012. http://etd.lib.metu.edu.tr/upload/12615323/index.pdf.
Texto completoResumen
This thesis presents various studies on energy efficient design of wireless networks. It starts
with a survey on recent shortest path based energy efficient routing algorithms developed for
ad hoc and sensor networks, making a comprehensive classification for these algorithms. In
addition to energy efficient design, sustainable and environmentally friendly deployment of
wireless networks demands increased use of renewable energy. However, this calls for novel
design principles to efficiently utilize the variation in the availability of the energy. The thesis
continues with an investigation of state-of-the-art resource management and scheduling
algorithms developed for energy harvesting wireless sensor networks. Building on the stateof-
the-art, the main contribution of this thesis is to formulate and solve a utility maximizing
scheduling problem in a multiuser broadcast channel with an energy harvesting transmitter.
The goal is to determine the optimal power and time allocations to users between energy arrivals.
The structural properties of the problem are analyzed, and its biconvexity is proved.
A Block Coordinate Descent (BCD) based algorithm is developed to obtain the optimal solution.
Two simple and computationally scalable heuristics, PTF and ProNTO, which mimic
the characteristics of the optimal policy, are proposed. Finally, an online algorithm, PTF-On,that will bypass the need for offline knowledge about the energy harvesting statistics, is developed.
PTF-On uses a Kalman filter based energy harvesting prediction algorithm, developed
in this thesis, to predict the energy that will arrive in the future.
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Ronasi, Keivan. "Resource allocation and scheduling in wireless mesh networks". Thesis, University of British Columbia, 2012. http://hdl.handle.net/2429/42751.
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The unreliability of wireless mesh networks creates challenge in designing high performance wireless networks in terms of network throughput, end-to-end delay, and fairness provisioning. In this thesis, the goal is to improve the network performance in terms of these metrics. We explore several techniques such as multipath routing, channel coding, network coding, and interference alignment. We consider resource allocation both in terms of average data rate provisioning and scheduling policies in a time slot basis.
First, we propose data rate and channel code rate allocation algorithms for networks with multiple paths to maximize the network throughput while all users can fairly exploit the network resources. We study the effect of adaptive and non-adaptive channel coding schemes. We also consider the end-to-end delay that each network flow experiences for data transmission. For that purpose, we formulate the problem of decreasing the end-to-end delay for network flows while improving the network throughput. Simulation results show that we can decrease the delay at the cost of a slight decrease in network throughput. We also formulate a data rate allocation problem in networks with network coding. Simulation results show that considering link reliabilities in the network coding design dramatically increases the network performance.
Data rate allocation algorithms provide the average data rates at which the source must transmit data. They do not determine scheduling on a time slot basis. To address that, we consider transmission scheduling in wireless networks. We also compare the suggested algorithm with a centralized optimal data rate allocation algorithm to verify that our algorithm follows the optimal solution. Through simulations, we show that fairness provisioning leads to higher network performance. We show that the suggested algorithm outperforms the current algorithms in the literature in terms of both network throughput and fairness provisioning.
Finally, we consider transmission scheduling in wireless multi-input multi-output (MIMO) systems. We formulate the problem of joint scheduling, interference alignment, and admission control in those networks and use Lyapunov stability theory to solve it. We also develop a heuristic approach to solve the problem in a semi-distributed manner.
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Tabatabaei, Yazdi Ehsan. "Adaptive Resource Allocation for Wireless Body Sensor Networks". Thesis, University of Canterbury. Computer Science and Software Engineering, 2014. http://hdl.handle.net/10092/9828.
Texto completoResumen
The IEEE 802.15.4 standard is an interesting technology for use in Wireless Body Sensor Networks (WBSN), where entire networks of sensors are carried by humans. In many environments the sensor nodes experience external interference for example, when the WBSN is operated in the 2.4 GHz ISM band and the human moves in a densely populated city, it will likely experience WiFi interference, with a quickly changing ``interference landscape''. In this thesis we propose Adaptive Resource Allocation schemes, to be carried out by the WBSN, which provided noticeable performance gains in such environments. We investigate a range of adaptation schemes and assess their performance both through simulations and experimentally.
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Yang, Jianjun. "RESOURCE ALLOCATION AND EFFICIENT ROUTING IN WIRELESS NETWORKS". UKnowledge, 2011. http://uknowledge.uky.edu/gradschool_diss/833.
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In wireless networks, devices (nodes) are connected by wireless links. An important issue is to set up high quality (high bandwidth) and efficient routing paths when one node wants to send packets to other nodes. Resource allocation is the foundation to guarantee high quality connections. In addition, it is critical to handle void areas in order to set up detour-free paths. Moreover, fast message broadcasting is essential in mobile wireless networks. Thus, my research includes dynamic channel allocation in wireless mesh networks, geographic routing in Ad Hoc networks, and message broadcasting in vehicular networks.
The quality of connections in a wireless mesh network can be improved by equip- ping mesh nodes with multi-radios capable of tuning to non-overlapping channels. The essential problem is how to allocate channels to these multi-radio nodes. We develop a new bipartite-graph based channel allocation algorithm, which can improve bandwidth utilization and lower the possibility of starvation. Geographic routing in Ad Hoc networks is scalable and normally loop-free. However, traditional routing protocols often result in long detour paths when holes exist. We propose a routing protocol-Intermediate Target based Geographic Routing (ITGR) to solve this problem. The novelty is that a single forwarding path can be used to reduce the lengths of many future routing paths. We also develop a protocol called Hole Detection and Adaptive Geographic Routing, which identifies the holes efficiently by comparing the length of a routing path with the Euclidean distance between a pair of nodes. We then set up the shortest path based on it. Vehicles play an important role in our daily life. During inter-vehicle communication, it is essential that emergency information can be broadcast to surrounding vehicles quickly. We devise an approach that can find the best re-broadcasting node and propagate the message as fast as possible.
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Zhu, Yongxu. "Efficient resource allocation for 5G hybrid wireless networks". Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1572470/.
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This thesis explores three directions of energy-efficiency(EE) and spectral efficiency(SE) under 5G wireless networks. Firstly, we study the optimization of power control for the small (two-user) interference channel in which the terminals are time-switched between the signal-processing and energy-harvesting phases. Both energy harvesting and signal-processing processes are during the downlink. The objective is to maximize the sum-rate, subject to the minimum data and harvested energy constraints at the receivers, assuming a fixed time-switching coefficient. The key contribution is using a geometric approach that analyzes the feasible region governed by the constraints, which gives rise to the optimal power control solution. Another topic focuses on the performance analysis of two user association schemes for wireless power transfer (WPT) in heterogeneous networks (HetNets) massive multiple-input multiple-output (MIMO) antennas, downlink for the WPT in the first phase and uplink for wireless information transfer (WIT) in the second phase. The two user association schemes considered in the analysis are the Downlink received signal power (DRSP) based approach for maximizing the harvested energy; and the uplink received signal power (URSP) based approach for minimizing the uplink path loss. In the downlink, we adopt a low-complexity approach for massive MIMO power transfer to recharge users. Then we derive the average uplink achievable rate with the harvested energy. The last topic analyses a large-scale mmWave ad hoc network in the randomly located eavesdroppers area, where eavesdroppers can still intercept the confidential messages, since they may reside in the signal beam. This chapter explores the potential of physical layer security in mmWave ad hoc networks. Specifically, we characterize the impact of mmWave channel characteristics, random blockages, and antenna gains on the secrecy performance. For the special case of the uniform linear array (ULA), a tractable approach is proposed to evaluate the average achievable secrecy rate.
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guo, wenxuan. "Resource Allocation and Performance Optimization in Wireless Networks". Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-dissertations/179.
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As wireless networks continue streaking through more aspects of our lives, it is seriously constrained by limited network resources, in terms of time, frequency and power. In order to enhance performance for wireless networks, it is of great importance to allocate resources smartly based on the current network scenarios. The focus of this dissertation is to investigate radio resource management algorithms to optimize performance for different types of wireless networks. Firstly, we investigate a joint optimization problem on relay node placement and route assignment for wireless sensor networks. A heuristic binary integer programming algorithm is proposed to maximize the total number of information packets received at the base station during the network lifetime. We then present an optimization algorithm based on binary integer programming for relay node assignment with the current node locations. Subsequently, a heuristic algorithm is applied to move the relay nodes to the locations iteratively to better serve their associated edge nodes. Secondly, as traditional goal of maximizing the total throughput can result in unbalanced use of network resources, we study a joint problem of power control and channel assignment within a wireless mesh network such that the minimal capacity of all links is maximized. This is essentially a fairness problem. We develop an upper bound for the objective by relaxing the integer variables and linearization. Subsequently, we put forward a heuristic approach to approximate the optimal solution, which tries to increase the minimal capacity of all links via setting tighter constraint and solving a binary integer programming problem. Simulation results show that solutions obtained by this algorithm are very close to the upper bounds obtained via relaxation, thus suggesting that the solution produced by the algorithm is near-optimal. Thirdly, we study the topology control of disaster area wireless networks to facilitate mobile nodes communications by deploying a minimum number of relay nodes dynamically. We first put forward a novel mobility model for mobile nodes that describes the movement of first responders within a large disaster area. Secondly, we formulate the square disk cover problem and propose three algorithms to solve it, including the two-vertex square covering algorithm, the circle covering algorithm and the binary integer programming algorithm. Fourthly, we explore the joint problem of power control and channel assignment to maximize cognitive radio network throughput. It is assumed that an overlaid cognitive radio network (CRN) co-exists with a primary network. We model the opportunistic spectrum access for cognitive radio network and formulate the cross-layer optimization problem under the interference constraints imposed by the existing primary network. A distributed greedy algorithm is proposed to seek for larger network throughput. Cross-layer optimization for CRN is often implemented in centralized manner to avoid co-channel interference. The distributed algorithm coordinates the channel assignment with local channel usage information. Thus the computation complexity is greatly reduced. Finally, we study the network throughput optimization problem for a multi-hop wireless network by considering interference alignment at physical layer. We first transform the problem of dividing a set of links into multiple maximal concurrent link sets to the problem of finding the maximal cliques of a graph. Then each concurrent link set is further divided into one or several interference channel networks, on which interference alignment is implemented to guarantee simultaneous transmission. The network throughput optimization problem is then formulated as a non-convex nonlinear programming problem, which is NP-hard generally. Thus we resort to developing a branch-and-bound framework, which guarantees an achievable performance bound.
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Shaqfeh, Mohammad. "Resource allocation and flexible scheduling in wireless networks". Thesis, University of Edinburgh, 2008. http://hdl.handle.net/1842/14386.
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Farsi, Abdelhak. "Planning and resource allocation for wireless mesh networks". Paris 13, 2012. http://scbd-sto.univ-paris13.fr/intranet/edgalilee_th_2012_farsi.pdf.
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Wireless mesh networks (WMNs) have emerged as a key technology for next generationwireless networks, showing rapid progress and inspiring numerous applications. In this thesis we emphasize on the planning and resource allocation in WMN. The work can be divided in three parts. In the first part, we investigate the problem of designing the access tier network. We aim at minimizing the installation cost, and maximizing the nominal throughput to offer to each user while minimizing the interference. We propose to deal with this multi-objective problem using two approaches. In the first approach we divide the access tier network planning issue into two problems: (1) the mesh router placement problem and (2) the frequency assignment problem. To deal with the mesh router positioning problem, we propose two strategies namely the Markov Cluster-Integer Linear Programming (MCLILP) and the Disk Covering algorithms. However, to resolve the frequency assignment problem, we propose to reduce the interference using the three algorithms: Predefined frequency Vector Approach (PFVA), Least-Interfering Channel Search (LICS) and the TPsbased Least Interfering Channel Search (TPs-LICS). We propose a second approach dealing jointly with both problems of mesh router positioning and channel assignment, namely the Three-Phase Heuristic Algorithm forWLAN planning (TPHA). This novel fast and scalable heuristic based on the potential field approach. In the second part, we deal with the backhaul topology design problem. This latter involves the following two issues: the backhaul topology formation problem and the capacity assignment problem. To overcome the complexity of this global problem, we propose the Backhaul Topology Formation Algorithm (BTFA) to solve the problem of topology formation while maximizing the capacity. However, we use an iterative-based Weighted Max-Min Fair Capacity Allocation algorithm to deal with a fair capacity assignment. In the third part, we deal with the dimensioning problem (or resource allocation) in mesh networks. We consider two different access technologies at the access tier: connectionless communication mode and connection-oriented communication mode. We propose a dimensioning methodology for each assumed technology in order to satisfy the objectives of maximizing the capacity at the backhaul tier and sharing it in a weighted max-min fair manner among all mesh routers. We evaluate the performance of our propositions and show their effectiveness by comparing them to the exact solutionLes réseaux maillés sans fils (Wireless Mesh Networks) sont apparus comme une technologie phare pour le développement des réseaux sans fils de nouvelle génération, subissant un développement rapide et inspirant un certain nombre d’applications. Dans cette thèses, on se focalise sur la planification et l’allocation de ressources dans WMN. Ce travail est divisé en trois volets. Dans le premier volet, nous traitons le problème de planification du réseau dorsal. Nous nous intéressons à la minimisation du coût d’installation, et la maximisation du débit nominal à offrir à chaque utilisateur, tout en minimisant l’interférence. Nous proposons de traiter ce problème multiobjectif en utilisant deux approches. Dans la première approche, nous définissons le problème de planification du réseau d’accès comme étant : (1) problème du positionnement de routeurs mesh et (2) problème d’affectation de canaux. Afin de résoudre le problème du positionnement des routeurs mesh, nous avons proposé deux stratégies : à savoir l’algorithme de Markov Cluster-Integer Linear Programming (MCLILP) et l’algorithme de disques couvrants. Par ailleurs, nous avons résolu le problème d’affectation de canaux par la proposition de trois algorithmes : Predefined frequency Vector Approach (PFVA), Least-Interfering Channel Search (LICS) and the TPsbased Least Interfering Channel Search (TPs-LICS). Ensuite, nous avons proposé une deuxième approche appelée Three-Phase Heuristic Algorithm for WLAN planning (TPHA). Notre deuxième approche permet d’optimiser conjointement les deux problèmes de positionnement de routeurs mesh et d’affectation de canaux. Cette nouvelle heuristique, rapide et évolutive, inspirée du domaine de la robotique, se base sur l’approche du champ de potentiel. Dans le deuxième volet, nous nous focalisons sur le problème de planification du réseau dorsal. Ce dernier, est défini comme étant : la formation de la topologie du réseau dorsal et l’affectation de sa capacité. Etant donné que la planification du réseau dorsal est un problème complexe, nous avons proposé une heuristique en deux phases. La première phase consiste en la formation de topologie en choisissant les liens qui maximisent la capacité totale du réseau dorsal. Tandis que la deuxième phase, permet le partage de la capacité du réseau dorsal entre les différents routeurs mesh selon l’équité Max-Min. Dans le troisième volet, nous nous intéressons au problème du dimensionnement (allocation de ressources) du réseau mesh à deux niveaux. Nous supposons deux technologies d’accès différentes : mode de communication non connecté et le mode connecté. Nous proposons une méthodologie de dimensionnement pour chaque mode de communication afin de satisfaire les deux objectifs de maximisation de la capacité et de la partager entre tous les routeurs mesh selon la stratégie d’équité Max-Min pondérée. Finalement, les algorithmes et modèles proposés ont été évalués en comparant leurs résultats à la solution exacte
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Awoyemi, Babatunde Seun. "Resource allocation optimisation in heterogeneous cognitive radio networks". Thesis, University of Pretoria, 2017. http://hdl.handle.net/2263/61327.
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Cognitive radio networks (CRN) have been tipped as one of the most promising paradigms for next
generation wireless communication, due primarily to its huge promise of mitigating the spectrum
scarcity challenge. To help achieve this promise, CRN develop mechanisms that permit spectrum
spaces to be allocated to, and used by more than one user, either simultaneously or opportunistically,
under certain preconditions. However, because of various limitations associated with CRN, spectrum
and other resources available for use in CRN are usually very scarce. Developing appropriate models
that can efficiently utilise the scarce resources in a manner that is fair, among its numerous and diverse
users, is required in order to achieve the utmost for CRN. 'Resource allocation (RA) in CRN' describes
how such models can be developed and analysed.
In developing appropriate RA models for CRN, factors that can limit the realisation of optimal solutions
have to be identified and addressed; otherwise, the promised improvement in spectrum/resource
utilisation would be seriously undermined. In this thesis, by a careful examination of relevant literature,
the most critical limitations to RA optimisation in CRN are identified and studied, and appropriate
solution models that address such limitations are investigated and proffered.
One such problem, identified as a potential limitation to achieving optimality in its RA solutions, is the
problem of heterogeneity in CRN. Although it is indeed the more realistic consideration, introducing
heterogeneity into RA in CRN exacerbates the complex nature of RA problems. In the study, three
broad classifications of heterogeneity, applicable to CRN, are identified; heterogeneous networks,
channels and users. RA models that incorporate these heterogeneous considerations are then developed
and analysed. By studying their structures, the complex RA problems are smartly reformulated as
integer linear programming problems and solved using classical optimisation. This smart move makes
it possible to achieve optimality in the RA solutions for heterogeneous CRN.
Another serious limitation to achieving optimality in RA for CRN is the strictness in the level of
permissible interference to the primary users (PUs) due to the activities of the secondary users (SUs).
To mitigate this problem, the concept of cooperative diversity is investigated and employed. In
the cooperative model, the SUs, by assisting each other in relaying their data, reduce their level of
interference to PUs significantly, thus achieving greater results in the RA solutions. Furthermore,
an iterative-based heuristic is developed that solves the RA optimisation problem timeously and
efficiently, thereby minimising network complexity. Although results obtained from the heuristic are
only suboptimal, the gains in terms of reduction in computations and time make the idea worthwhile,
especially when considering large networks.
The final problem identified and addressed is the limiting effect of long waiting time (delay) on the
RA and overall productivity of CRN. To address this problem, queueing theory is investigated and
employed. The queueing model developed and analysed helps to improve both the blocking probability
as well as the system throughput, thus achieving significant improvement in the RA solutions for
CRN.
Since RA is an essential pivot on which the CRN's productivity revolves, this thesis, by providing
viable solutions to the most debilitating problems in RA for CRN, stands out as an indispensable
contribution to helping CRN realise its much-proclaimed promises.Thesis (PhD)--University of Pretoria, 2017.
Electrical, Electronic and Computer Engineering
PhD
Unrestricted
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Tsimba, Hilary Mutsawashe. "Queueing based resource allocation in cognitive radio networks". Diss., University of Pretoria, 2005. http://hdl.handle.net/2263/66250.
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With the increase in wireless technology devices and mobile users, wireless radio spectrum is coming under strain. Networks are becoming more and more congested and free usable spectrum is running out. This creates a resource allocation problem. The resource, wireless spectrum, needs to be allocated to users in a manner such that it is utilised efficiently and fairly. The objective of this research is to find a solution to the resource allocation problem in radio networks, i.e to increase the efficiency of spectrum utilisation by making maximum use of the spectrum that is currently available through taking advantage of co-existence and exploiting interference limits. The solution proposed entails adding more secondary users (SU) on a cognitive radio network (CRN) and having them transmit simultaneously with the primary user. A typical network layout was defined for the scenario. The interference temperature limit (ITL) was exploited to allow multiple SUs to share capacity. Weighting was applied to the SUs and was based on allowable transmission power under the ITL. Thus a more highly weighted SU will be allowed to transmit at more power. The weighting can be determined by some network-defined rule. Specific models that define the behaviour of the network were then developed using queuing theory, specifically weighted processor sharing techniques. Optimisation was finally applied to the models to maximize system performance. Convex optimization was deployed to minimize the length of the queue through the power allocation ratio. The system was simulated and results for the system performance obtained. Firstly, the performance of the proposed models under the processor-sharing techniques was determined and discussed, with explanations given. Then optimisation was applied to the processor-sharing results and the performance was measured. In addition, the system performance was compared to other existing solutions that were deemed closest to the proposed models.Dissertation (MEng)--University of Pretoria, 2017.
Electrical, Electronic and Computer Engineering
MEng
Unrestricted
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LI, WEI. "RESOURCE ALLOCATION IN INTEGRATED WIRELESS AND MOBILE NETWORKS". University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1129163674.
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Xia, Qiuyan. "Rate adaptation and resource allocation for wireless networks /". View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?CSED%202008%20XIA.
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Wang, Rui. "Resource allocation in high data-rate wireless networks /". View abstract or full-text, 2008. http://library.ust.hk/cgi/db/thesis.pl?ECED%202008%20WANGR.
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Akter, Lutfa. "Modeling, forecasting and resource allocation in cognitive radio networks". Diss., Manhattan, Kan. : Kansas State University, 2010. http://hdl.handle.net/2097/3892.
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Kwasinski, Andres. "Cross-layer resource allocation protocols for multimedia CDMA networks". College Park, Md. : University of Maryland, 2004. http://hdl.handle.net/1903/1988.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2004.Thesis research directed by: Electrical Engineering. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Curescu, Calin. "Utility-based Optimisation of Resource Allocation for Wireless Networks". Doctoral thesis, Linköping University, Linköping University, RTSLAB, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-7405.
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From providing only voice communications, wireless networks aim to provide a wide range of services in which soft real-time, high priority critical data, and best effort connections seamlessly integrate. Some of these applications and services have firm resource requirements in order to function properly (e.g. videoconferences), others are flexible enough to adapt to whatever is available (e.g. FTP). Providing differentiation and resource assurance is often referred to as providing quality of service (QoS). In this thesis we study how novel resource allocation algorithms can improve the offered QoS of dynamic, unpredictable, and resource constrained distributed systems, such as a wireless network, during periods of overload.
We propose and evaluate several bandwidth allocation schemes in the context of cellular, hybrid and pure ad hoc networks. Acceptable quality levels for a connection are specified using resource-utility functions, and our allocation aims to maximise accumulated systemwide utility. To keep allocation optimal in this changing environment, we need to periodically reallocate resources. The novelty of our approach is that we have augmented the utility function model by identifying and classifying the way reallocations affect the utility of different application classes. We modify the initial utility functions at runtime, such that connections become comparable regardless of their flexibility to reallocations or age-related importance.
Another contribution is a combined utility/price-based bandwidth allocation and routing scheme for ad hoc networks. First we cast the problem of utility maximisation in a linear programming form. Then we propose a novel distributed allocation algorithm, where every flow bids for resources on the end-to-end path depending on the resource ``shadow price'', and the flow's ``utility efficiency''. Our periodic (re)allocation algorithms represent an iterative process that both adapts to changes in the network, and recalculates and improves the estimation of resource shadow prices.
Finally, problems connected to allocation optimisation, such as modelling non-critical resources as costs, or using feedback to adapt to uncertainties in resource usage and availability, are addressed.
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Dybdahl, Sigbjørn Hernes. "Radio Resource Allocation for Increased Capacity in Cellular Networks". Thesis, Norwegian University of Science and Technology, Department of Electronics and Telecommunications, 2007. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-8777.
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Cellular networks are widely deployed for wireless communication, and as the number of users of these networks increase, so does the need for higher spectral efficiency. Clever measures have to be taken in order to increase throughput for wireless networks because of the scarcity of radio resources. Ever higher rates are demanded, but we also want to conserve a fair distribution of the available resources. Therefore, we consider the problem of joint power allocation and user scheduling, while achieving a desired level of fairness in wireless cellular systems. Dynamic resource allocation is employed for the full reuse networks simulated, in order to cope with inter-cell interference and to optimize spectrum efficiency. Binary power allocation is implemented and compared to the performance without power control, for minimum transmit power levels equal to 0 and greater than 0. We show that binary power control with individual power levels for each cell is optimal for two-cell networks. We also present an extension to the proportional fair scheduling for multi-cell networks, and analyze its performance for different cell sizes and time windows. Finally, we highlight the equality between multi-cell, multi-user and multi-carrier proportional fair scheduling. Simulation results show how power control and user scheduling increase throughput, reduce power consumption and achieve a desired level of fairness. Hence, we can obtain considerable gains for the network throughput through adaptive power allocation and multiuser diversity.