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Yuan Xue

Bio: Yuan Xue is an academic researcher from Vanderbilt University. The author has contributed to research in topics: Wireless network & Scheduling (computing). The author has an hindex of 31, co-authored 110 publications receiving 3368 citations. Previous affiliations of Yuan Xue include University of Illinois at Urbana–Champaign.


Papers
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Journal ArticleDOI
TL;DR: A new price-based resource allocation framework in wireless ad hoc networks to achieve optimal resource utilization and fairness among competing end-to-end flows is proposed and a two-tier iterative algorithm is presented.
Abstract: The shared-medium multihop nature of wireless ad hoc networks poses fundamental challenges to the design of effective resource allocation algorithms that are optimal with respect to resource utilization and fair across different network flows. None of the existing resource allocation algorithms in wireless ad hoc networks have realistically considered end-to-end flows spanning multiple hops. Moreover, strategies proposed in wireline networks are not applicable in the context of wireless ad hoc networks, due to their unique characteristics of location-dependent contention. In this paper, we propose a new price-based resource allocation framework in wireless ad hoc networks to achieve optimal resource utilization and fairness among competing end-to-end flows. We build our pricing framework on the notion of maximal cliques in wireless ad hoc networks, as compared to individual links in traditional wide-area wireline networks. Based on such a price-based theoretical framework, we present a two-tier iterative algorithm. Distributed across wireless nodes, the algorithm converges to a global network optimum with respect to resource allocations. We further improve the algorithm toward asynchronous network settings and prove its convergence. Extensive simulations under a variety of network environments have been conducted to validate our theoretical claims.

237 citations

Proceedings ArticleDOI
11 May 2003
TL;DR: This paper shows and proves that, independent of the MAC layer protocol being used, the BDP of a path in MANET cannot exceed the round-trip hop-count of the path, and proposes an adaptive CWL setting strategy to dynamically adjust TCP's CWL according to the current RTHC of its path.
Abstract: Improving TCP performance has long been the focus of many research efforts in mobile ad hoc networks (MANET). In this paper, we address one aspect of this endeavor: how to properly set TCP's congestion window limit (CWL) to achieve optimal performance. Past research has shown that using a small CWL improves TCP performance in certain scenarios [M. Gerla et al., Feb. 1999], [Z. Fu et al., Apr. 2003], however, no comprehensive study has been given. To this end, we turn the problem of setting TCP's optimal CWL into identifying the bandwidth-delay product (BDP) of a path in MANET. We first show and prove that, independent of the MAC layer protocol being used, the BDP of a path in MANET cannot exceed the round-trip hop-count (RTHC) of the path. We further refine this upper bound based on the IEEE 802.11 MAC layer protocol, and show that in a chain topology, a tighter upper bound exists, which is approximately 1/5 of the RTHC of the path. Based on this tighter bound, we propose an adaptive CWL setting strategy to dynamically adjust TCP's CWL according to the current RTHC of its path. Using ns-2 simulations, we show that our simple strategy improves TCP performance by 8% to 16% in a dynamic MANET environment.

199 citations

Proceedings ArticleDOI
14 Nov 2001
TL;DR: This work presents a novel scheme to perform scalable location management, and proposes a hierarchical addressing model for mobile ad-hoc networks, where node locations could be represented at different accuracy levels.
Abstract: In ad-hoc networks, geographical routing protocols take advantage of location information so that stateless and efficient routing is feasible. However such routing protocols are heavily dependent on the existence of scalable location management services. We present a novel scheme to perform scalable location management. With any location management schemes, a specific node, A, in the network trusts a small subset of nodes, namely its location servers, and periodically updates them with its location. Our approach adopts a similar strategy, but a different and original approach to select such location servers. First, we present a selection algorithm used to designate location servers of a node by its identifier. Second, we propose a hierarchical addressing model for mobile ad-hoc networks, where node locations could be represented at different accuracy levels. With this approach, different location servers may carry location information of different levels of accuracy and only a small set of location servers needs to be updated when the node moves. Through rigorous theoretical analysis, we are able to show that the control message overhead is bounded under our scheme. Finally, simulation results are presented to demonstrate the performance of our location management scheme.

179 citations

Journal ArticleDOI
TL;DR: An algorithm is designed, which utilizes the unique characteristic of data aggregation, and is proved to reduce the running time of the fastest existing algorithm by a factor of K, K being the number of commodities.
Abstract: This paper studies energy efficient routing for data aggregation in wireless sensor networks. Our goal is to maximize the lifetime of the network, given the energy constraint on each sensor node. Using linear programming (LP) formulation, we model this problem as a multicommodity flow problem, where a commodity represents the data generated from a sensor node and delivered to a base station. A fast approximate algorithm is presented, which is able to compute (1-e)-approximation to the optimal lifetime for any e > 0. Then along this baseline, we further study several advanced topics. First, we design an algorithm, which utilizes the unique characteristic of data aggregation, and is proved to reduce the running time of the fastest existing algorithm by a factor of K, K being the number of commodities. Second, we extend our algorithm to accommodate the same problem in the setting of multiple base stations, and study its impact on network lifetime improvement. All algorithms are evaluated through both solid theoretical analysis and extensive simulation results.

146 citations

Proceedings ArticleDOI
13 Mar 2008
TL;DR: The CareNet system architecture, software development, and the results of the field studies are described, which provide both highly reliable and privacy-aware patient data collection, transmission and access.
Abstract: CareNet is an integrated wireless sensor environment for remote healthcare that uses a two-tier wireless network and an extensible software platform. CareNet provides both highly reliable and privacy-aware patient data collection, transmission and access. This paper describes our system architecture, software development, and the results of our field studies.

125 citations


Cited by
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Journal ArticleDOI
TL;DR: The current state-of-art of WBANs is surveyed based on the latest standards and publications, and open issues and challenges within each area are explored as a source of inspiration towards future developments inWBANs.
Abstract: Recent developments and technological advancements in wireless communication, MicroElectroMechanical Systems (MEMS) technology and integrated circuits has enabled low-power, intelligent, miniaturized, invasive/non-invasive micro and nano-technology sensor nodes strategically placed in or around the human body to be used in various applications, such as personal health monitoring. This exciting new area of research is called Wireless Body Area Networks (WBANs) and leverages the emerging IEEE 802.15.6 and IEEE 802.15.4j standards, specifically standardized for medical WBANs. The aim of WBANs is to simplify and improve speed, accuracy, and reliability of communication of sensors/actuators within, on, and in the immediate proximity of a human body. The vast scope of challenges associated with WBANs has led to numerous publications. In this paper, we survey the current state-of-art of WBANs based on the latest standards and publications. Open issues and challenges within each area are also explored as a source of inspiration towards future developments in WBANs.

1,359 citations

Journal ArticleDOI
TL;DR: This paper provides a detailed investigation of sensor devices, physical layer, data link layer, and radio technology aspects of BAN research, and presents a taxonomy of B Ban projects that have been introduced/proposed to date.
Abstract: Advances in wireless communication technologies, such as wearable and implantable biosensors, along with recent developments in the embedded computing area are enabling the design, development, and implementation of body area networks. This class of networks is paving the way for the deployment of innovative healthcare monitoring applications. In the past few years, much of the research in the area of body area networks has focused on issues related to wireless sensor designs, sensor miniaturization, low-power sensor circuitry, signal processing, and communications protocols. In this paper, we present an overview of body area networks, and a discussion of BAN communications types and their related issues. We provide a detailed investigation of sensor devices, physical layer, data link layer, and radio technology aspects of BAN research. We also present a taxonomy of BAN projects that have been introduced/proposed to date. Finally, we highlight some of the design challenges and open issues that still need to be addressed to make BANs truly ubiquitous for a wide range of applications.

1,239 citations

Journal ArticleDOI
TL;DR: The results show that by proper resource management, D2D communication can effectively improve the total throughput without generating harmful interference to cellular networks.
Abstract: We consider Device-to-Device (D2D) communication underlaying cellular networks to improve local services. The system aims to optimize the throughput over the shared resources while fulfilling prioritized cellular service constraints. Optimum resource allocation and power control between the cellular and D2D connections that share the same resources are analyzed for different resource sharing modes. Optimality is discussed under practical constraints such as minimum and maximum spectral efficiency restrictions, and maximum transmit power or energy limitation. It is found that in most of the considered cases, optimum power control and resource allocation for the considered resource sharing modes can either be solved in closed form or searched from a finite set. The performance of the D2D underlay system is evaluated in both a single-cell scenario, and a Manhattan grid environment with multiple WINNER II A1 office buildings. The results show that by proper resource management, D2D communication can effectively improve the total throughput without generating harmful interference to cellular networks.

1,093 citations