摘要
无线传感器网络是一种集信息感知、采集、处理和传输为一体的网络系统,它将逻辑上的信息世界和客观上的物理世界联系在一起,正深刻地改变着人与自然的交互方式,因而被广泛地应用于军事、工业、农业、医疗和抢险救灾等领域。覆盖控制是无线传感器网络所提供服务质量的基本问题之一,其目的是利用部署的传感器节点来感知目标区域或目标对象,并达到所获取信息的有效性和完整性。覆盖控制决定了传感器网络对物理世界的感知能力,是推动传感器网络从理论走向应用的必经之路。
本文研究的目的是针对以随机方式部署的无线传感器网络设计具有节能特征的网络覆盖优化算法和协议。主要是从覆盖率控制模型、多属性目标覆盖、网络多重覆盖以及移动目标的动态覆盖等方面展开研究,遵循提高网络的能量利用效率的设计准则,以达到实现一个能量高效的网络覆盖控制优化方案目的。
本文的主要工作包括以下四个方面：
(1)针对随机分布的网络覆盖控制问题研究,提出了基于概率的网络覆盖控制模型PCCM。考虑到网络边界效应影响,模型首先计算传感器节点位于网络内部及其边界两种情况下覆盖面积的期望值,进而得到节点总覆盖面积的期望值；根据用户对覆盖率的要求,依据条件概率分布函数计算得到所需要部署节点的数量。模型反映了网络覆盖率与部署节点数量、节点感知半径与监测区域面积之间的函数关系。在此基础上,依据随机图理论推导得到网络连通性的概率模型。PCCM模型可以指导用户对网络覆盖率及连通率等网络属性的控制。
(2)针对异构传感器网络的多属性目标覆盖研究,利用线性规划工具将其建模为最优值覆盖集求解问题,提出了一种基于分簇结构的目标覆盖算法CTCA。其核心思想是依据节点的剩余能量的多少及感应能力的高低,在每个簇结构内求解局部最优覆盖集,然后在此基础上得到接近于最优解的全局覆盖集,最后调度节点相应的感应模块去覆盖其感知范围内同属性的目标。实验结果表明所提出的算法能够有效提高网络节点的能量利用效率,延长网络生存期。
(3)针对无线传感器网络多重覆盖算法研究,借助于勒洛三角形的几何特征提出判断区域覆盖度的定理,并以此为基础设计了一个基于勒洛三角形的多重覆盖算法RTC。算法的核心思想是利用节点局部位置信息,通过在节点感应圆周上构造勒洛三角形和所提出的覆盖定理来判断网络的覆盖度,并根据网络节点的剩余能量的高低进行节点状态调度。实验数据分析表明RTC算法在确保网络覆盖质量的条件下能够有效减少网络中冗余节点的数量,从而提高网络能量利用效率。
(4)针对移动目标的实时监测协议研究,提出了一个自适应移动目标动态覆盖协议。协议的主要思想是首先对移动目标周围的节点,利用竞争机制构造出一个动态覆盖组对目标定位与实时监测；然后利用所提出的目标移动位置预测模型及节点状态调度策略来更新该动态覆盖组,这样可以有效提高节点对目标实时监测的时效性和能量利用效率。最后,借助于节点自适应数据报告频率自调整机制而实现降低网络节点之间通信量的目的。实验数据分析表明所提出的协议在网络能量利用效率、目标定位精度等方面具有很好的性能表现。
综上所述,本文针对无线传感器网络的节点覆盖控制问题提出了相应的解决方案,对于推动无线传感器网络的研究和实用化具有一定的理论意义和应用价值。
Wireless sensor network (WSN), as an integrated network which can perform information sensing, gathering, processing and delivering, can connect the logic information world with the real physical world. It has been greatly changing the way of interaction between human and nature. There are wide potential applications for WSNs, such as military affairs, industry, agriculture, healthcare, disaster succoring, etc. Coverage control is one of basic issue of quality of service (QoS) on WSNs. The goal of coverage control is to sense the monitoring area or targets by distributed sensors, so WSNs can collect valid and complete target information. Coverage control determines the monitoring performance on physical world for WSNs, so it is the indispensable road to accelerate the practicability of WSNs.
This thesis is primarily to design optimal coverage algorithms and protocols with characteristic of energy saving for WSNs. Based on these several aspects--coverage ratio control model, polytype target coverage, multiple coverage degree, and dynamic coverage for mobile target, it follows the design criteria of reducing network consumption to achieve the purpose of an energy-efficient network coverage optimization scheme.
The major work and innovative achievements of this thesis can be divided into the following four chapters:
(1) Aimed at coverage ratio control of network, we propose a probability-based coverage control model (PCCM). Considering the border effect, PCCM firstly calculates the expected coverage area of sensors under the two cases:sensors located in the monitoring area, and sensors located near the border of monitoring area. Then, it gets the total expected coverage area of the deployed sensors. According to the requirements of users for coverage ratio, it gets the number of needed sensors to be deployed under the conditional probability distribution function. PCCM reflects the relationships between network coverage ratio and the number of deployed sensors, the sensing radius of sensor, the area of monitoring region. Based on the PCCM and the random graph theory, we also propose a network connectivity probability model. The proposed model can help users to control the network coverage and connectivity ratio in deploying sensors to the monitoring area.
(2) Aimed at polytype target coverage for heterogeneous WSNs, we propose a cluster-based target coverage algorithm (CTCA), modeling polytype target coverage to optimal cover set problem based on linear programming. The key idea is to construct an optimal cover set in each cluster by the residual energy and coverage capability of sensors. Then, it achieves a suboptimal cover set for the whole network. Finally, CTCA schedules the corresponding sensing modules of sensor to cover the targets with same attribute. The simulation results show that the proposed algorithm can improve the energy efficiency and prolong the network lifetime.
(3) Aimed at multiple degree coverage for WSNs, we propose a Reuleaux triangle-based к-coverage algorithm (RTC) on the basis of the coverage degree judgment theorem by using the geometrical characters of Reuleaux triangle. The key idea is that using the local position information of sensors to judge the coverage degree by constructing the Reuleaux triangle on the sensing circle of sensor. The algorithm schedules the suitable sensors into active status to cover target area. The simulation results show that the proposed algorithm can effectively decrease the number of sensors in the active status satisfied the coverage degree requirements, which improves the energy efficiency of network.
(4) Aimed at real-time monitoring for mobile target, we propose an adaptive mobile target dynamic coverage protocol (AMTDCP). The main idea is that first the sensors near the target construct a dynamic coverage group (DCG) based on competition mechanism to locate and real-time monitor the target. Then, we use the proposed mobile target position prediction model and sensor status scheduling mechanism to update the DCG, which can improve the dynamic coverage quality and energy efficiency greatly. Finally, the communications volume of network is decreased by an adaptive data report frequency mechanism. The simulation results show that the proposed protocol has a better performance on the metrics of the total energy consumption of network, positioning accuracy, etc.
In summary, this thesis focuses on coverage control problems and proposes its solutions. Our research has academic and practical value for advancing the theory and practicability in WSNs.
引文
[1]I. Akyildiz, W. Su, Y. Sankarasubramaniam, et al. A survey on sensor networks [J]. IEEE Communications Magazine,2002,40(8):102-114.
[2]孙利民,李建中,陈渝,等.无线传感器网络[M].北京：清华大学出版社,2005.
[3]J. Yick, B. Mukherjee and D. Ghosal, Wireless sensor network survey [J], Computer Networks,2008,52(12):2292-2330.
[4]G. Anastasi, M. Conti, M. Francesco, et al. Energy conservation in wireless sensor networks:a survey [J]. Ad Hoc Networks,2009,7(3):537-568.
[5]A. Pantelopoulos and N.G. Bourbakis. A survey on wearable sensor-based systems for health monitoring and prognosis [J]. IEEE Transactions on Systems, Man, and Cybernetics, Part C:Applications and Reviews,2010,40(1):1-12.
[6]李建中,高宏.无线传感器网络的研究进展[J].计算机研究与发展,2008,45(1)：1-15.
[7]B. Wang. Coverage problems in sensor networks:a survey [J]. ACM Computer Survey,2011, Vol.43, No.4, Article 32,53 pages. DOI:10.1145/1978802.1978811.
[8]S. Ehsan, and B. Hamdaoui. A survey on energy-efficient routing techniques with QoS assurances for wireless multimedia sensor networks [J]. IEEE Communications Survey & Tutorials,2012,14(2):265-278.
[9]周新莲.基于分簇技术的移动无线传感器网络数据收集协议研究[D].博士学位论文,中南大学,2011.
[10]Embedded Sensors Project, http://projects.cerias.purdue.edu/esp/.
[11]Embedded Networks and Applications Lab (Yale Univ.). http://www.eng.yale.edu/enalab/
[12]WSNL. http://wsnl.stanford.edu/tutorial.php/
[13]Networks and Mobile Systems, http://nms.csail.mit.edu/
[14]u-Adaptive Multi-domain Power aware Sensors. http://www-mtl.mit.edu/researchgroups/icsystems/uamps/
[15]Center for Embedded Networked Sensing.http://research.cens.ucla.edu/
[16]WINS.http://www.janet.ucla.edu/wins/
[17]The Berkeley Wireless Research Center.http://bwrc.eecs.berkeley.edu/
[18]Wireless Embedded Systems.http://webs.cs.berkeley.edu/
[19]Robotic Research Lab. http://www.robotics.usc.edu/robomote/
[20]4D Volcano Tomography.http://sensorweb.cs.gsu.edu/
[21]Intel. http://www.intel.com/research/exploratory/wireless_sensors.htm/
[22]Networked Embeddded Computing. http://research.microsoft.com/nec/
[23]Sensor System. http://www.zurich.ibm.com/sys/energy/sensorsystems.html
[24]Intel Mote, http://www.intel.com/research/exploratory/motes.htm/
[25]Sensor Board. http://www.xbow.com/
[26]Telos Mote. http://www.moteiv.com/
[27]Medusa Mk-s Mote. http://nesl.ee.ucla.edu/projects/ahlos/mk2/
[28]MiniGains. http://www.nbicc.com/
[29]TinyOS. http://www.tinyos.net/
[30]SOS System. http://nesl.ee.ucla.edu/projects/SOS/
[31]孙利民,李波,周新运.无线传感器网络的拥塞控制技术[J].计算机研究与发展,2008,45(1)：63-72.
[32]崔莉,鞠海玲,苗勇.无线传感器网络研究进展[J].计算机研究与发展,2005,42(1)：161-174.
[33]S. He, J. Chen, and Y. Sun. Coverage and connectivity in duty-cycled wireless sensor network for event monitoring [J], IEEE Transactions on Parallel and Distributed Systems,2012,23(3):475-482.
[34]余磊,李建中,骆吉洲.一种无线传感器网络分布式安全成簇协议[J].软件学,2009,20(10)：2705-2720.
[35]班冬松,温俊,蒋杰,等.移动无线传感器网络k-栅栏覆盖构建算法[J].软件学报,2011,22(9)：2089-2103.
[36]F. Ren, T. He, S.K. Das, et al. Traffic-aware dynamic routing to alleviate congestion in wireless sensor networks [J], IEEE Transactions on Parallel and Distributed Systems,2011,22(9):1585-1599.
[37]L. Liu and H. Ma. On coverage of wireless sensor networks for rolling terrains [J]. IEEE Transactions on Parallel and Distributed System.2012,23(1):118-125.
[38]肖甫,王汝传,叶晓国,等.基于改进势场的有向传感器网络路径覆盖增强算法[J].计算机研究与发展,2009,46(2)：2126-2133.
[39]Y. Cai, W. Lou, M. Li, et al. Energy efficient target-Oriented scheduling in directional sensor networks [J]. IEEE Transactions on Computers,2009,58(9): 1259-1274.
[40]张士庚,曾英佩,陈力军,等.移动传感器网络中定位算法的性能评估[J].软件学报,2011,22(7)：1597-1611.
[41]陶丹,马华东.有向传感器网络覆盖控制算法[J].软件学报,2011,22(10)：2317-2334.
[42]韩志杰,黄刘生,王汝传,等.一种基于自适应半径调整的无线传感器网络覆盖控制算法[J].计算机研究与发展,2010,47(z2)：69-72.
[43]张茜,孙力娟,郭剑,等.基于网络划分的节点调度覆盖算法[J].计算机研究与发展,2011,48(Sup.)：111-115.
[44]J. O'Rourke. Art gallery theorems and algorithms [M]. Oxford University Press, 1987.
[45]J. O'Rourke. Computational geometry column 15 [J]. International Journal of Computational Geometry and Applications,1992,2:215-217.
[46]M. Marengoni, B.A. Draper, A. Hanson, et al. A system to place observers on a polyhedral terrain in polynomial time [J]. Image and Vision Computing,2000, 18(10):773-780.
[47]R. Williams. The geometrical foundation of natural structure [M]. A Source book of Design. Dover, New York,1979,51-52.
[48]A. Heppes and H. Melissen. Covering a rectangle with equal circles [J]. Periodica Mathematica Hungarica,1997,34(1-2):65-81.
[49]J. Melissen and P. Schuur. Improved coverings of a square with six and eight equal circles [J]. Electronic Journal of Combinatorics,1996,3(1):1-9.
[50]K. Nurmela and P. Ostergard. Covering a square with up to 30 eqval circles [M]. Research Report A62, Helsinki Univeristy of Technology, Laboratory for Theoretical Computer Science, Espoo, Finland,2000.
[51]宋文主编.无线传感器网络技术与应用[M].北京：电子工业出版社,2007.
[52]范高俊.无线传感器网络覆盖性能评估与提高[D].长沙：国防科学技术大学,博士学位论文,2009.
[53]K. Chakrabarty, S. Iyengar, H. Qi, et al. Grid coverage for surveillance and target location in distributed sensor networks [J]. IEEE Transactions on Computers, 2002,51(12):1448-1453.
[54]S. Dhillon, K. Chakrabarty, and S. Iyengar. Sensor placement for grid coverage under imprecise detections [C]. Proceedings of International Conference on Information Fusion,2002,1581-1587.
[55]S. Dhillon and K. Chakrabarty. Sensor placement for effective coverage and surveillance in distributed sensor networks [C]. Proceedings of Wireless Communications and Networking Conference (WCNC).2003,1609-1614.
[56]Y. Zou and K. Chakrabarty. Sensor deployment and target localization in distributed sensor networks [J]. ACM Transactions on Embedded computing Systems,2004,3(1):61-91.
[57]Y. Zou and K. Chakrabarty. Sensor deployment and target localization in distributed sensor networks [J]. ACM Transaction on Embedded System,2004, 61-91.
[58]M. A. Guvensan, and A. G. Yavuz. On coverage issues in directional sensor networks:a survey [J]. Ad Hoc Networks,2011,9(7):1238-1255.
[59]J. Ai, A. and Abouzeid. Coverage by directional sensors in randomly deployed wireless sensor networks [J]. Journal of Combinatorial Optimization,2006,11(1): 21-41.
[60]陶丹,马华东,刘亮.基于虚拟势场的有向传感器网络覆盖增强算法[J].软件学报,2007,18(5)：1152-1163.
[61]M. Younis and K. Akkaya. Strategies and techniques for node placement in wireless sensor networks:a suvey [J]. Ad Hoc Networks,2008,6(4):621-655.
[62]X. Bai, Z. Yun, D. Xuan, et al. Optimal deployment patterns for four-connectivity and full-coverage wireless sensor networks [J]. IEEE Transactions on Mobile Computing (TMC),2010,9(3):435-448.
[63]Q. Wu, N. S. V. Rao, X. Du, et al. On efficient deployment of sensors on planar grid [J]. Computer Communications,2007,30(14-15):2721-2734.
[64]王换招,孟凡治,李增智.高效节点的无线传感器网络覆盖保持协议[J].软件学报,2010,21(12)：3124-3137.
[65]H.M. Amman and S.K. Das. Centralized and clustered k-coverage protocols for wireless sensor networks [J]. IEEE Transactions on Computers,2012,61(1): 118-133.
[66]H.M. Ammari and S.K. Das. Critical density for coverage and connectivity in three-dimensional wireless sensor networks using continuum percolation [J]. IEEE Transactions on Parallel and Distributed Systems,2009,20(6):872-885.
[67]W. An, F. Shao, and H. Meng. The coverage-control optimization in sensor network subject to sensing area [J]. Computers and Mathematics with Applications,2009,57(4):529-539.
[68]C. Chang and H. Chang. Energy-aware node placement, topology control and MAC scheduling for wireless sensor networks [J]. Computer Networks,2008, 52(11):2189-2204.
[69]M. Lu, J. Wu, M. Cardei, et al. Energy-efficient connected coverage of discrete targets in wireless sensor networks [J]. International Journal of Ad Hoc and Ubiquitous Computing,2009,4(3-4):137-147.
[70]C. Yu, K. Yu, W. So, et al. Target coverage in wireless sensor networks [C]. Proceedings of Mobile Ad-hoc and Sensor Networks (MSN),2011,408-412.
[71]S. Tao and M. Krunz. Coverage-time optimization for clustered wireless sensor networks:a power-balancing approach [J]. IEEE/ACM Transactions on Networking,2010,18(1):202-215.
[72]王良民,李菲,秦颖.基于移动节点的无线传感器网络覆盖洞修复方法[J].通信学报,2011,32(4)：1-8.
[73]J. Cortes, S. Martinez, T. Karatas, et al. Coverage control for mobile sensing networks [J]. IEEE Transactions on Robotics and Automation,2004,20(2): 243-255.
[74]H. Zhang and J. Hou. On deriving the upper bound of alpha-lifetime for large sensor networks [C]. Proceedings of the 5th ACM international symposium on Mobile ad hoc networking and computing (MobiHoc),2004,121-132.
[75]C. Huang and Y. Tseng. The coverage problem in a wireless sensor networks [J]. Journal of Mobile Networks and Applications,2005,10(4):519-528.
[76]C. Huang, Y. Tseng, and L. Lo. The coverage problem in three-dimensional wireless sensor networks [C]. Proceedings of IEEE Global Telecommunications Conference (GlboalCom),2004,3182-3186.
[77]B. Liu, P. Brass, and O. Dousse. Mobility improves coverage of sensor networks [C]. Proceedings of the 6th ACM international symposium on Mobile ad hoc networking and computing (MobiHoc),2005,300-308.
[78]R. Kershner. The number of circles covering a set [J]. American Journal of Mathematics,1939,61(3):665-671.
[79]H. Zhang and J. C. Hou, Maintaining sensing coverage and connectivity in large sensor networks [J]. Wireless Ad Hoc and Sensor Networks,2005,1:89-123.
[80]I. Rajagopal, K. Koushik, and B. Suman. Low-coordination topologies for redundancy in sensor networks [C]. Proceedings of the 6th ACM International Symposium on Mobile Ad Hoc Networking and Computing (MobiHoc),2005, 332-342.
[81]X. Bai, S. Kumar, Z. Yun, et al. Deploying wireless sensors to achieve both coverage and connectivity [C]. Proceedings of the 7th ACM International Symposium on Mobile Ad Hoc Networking and Computing (MobiHoc),2006, 131-142.
[82]X. Bai, Z. Yun, D. Xuan, et al. Deploying four-connectivity and full-coverage wireless sensor networks [C]. Proceedings of the 27th IEEE Conference on Computer Communications (INFOCOM),2008,296-300.
[83]J. Wu, F. Dai, M. Gao, et al. On calculating power aware connected dominating sets for efficient routing in ad hoc networks [J]. Journal of Communications and Networks,2002,4(1):59-70.
[84]V. Raghunathan, C. Schurgers, S. Park, et al. Energy aware wireless micro sensor networks [J]. IEEE Signal Processing Magazine,2002,19(2):40-50.
[85]S. Slijepcevic and M. Potkonjak. Power efficient organization of wireless sensor networks [C]. Proceedings of IEEE International Conference on Communications (ICC),2001,472-476.
[86]C. Liu, K. Wu, and V. King. Randomized coverage-preserving scheduling schemes for wireless sensor networks [C]. Proceedings of IFIP Networking,2005, 956-967.
[87]Z. Abrams, A. Goel, and S. Plotkin. Set k-cover algorithms for energy efficient monitoring in wireless sensor networks [C]. Proceedings of IPSN,2004,424-432.
[88]F. Ye, G. Zhong, J. Cheng, et al. PEAS:a robust energy conserving protocol for long-lived sensor networks [C]. Proceedings of the 23rd IEEE International Conference on Distributed Computing Systems (ICDCS),2003,28-37.
[89]T. He, S. Krishnamurthy, and J.A. Stankovic. Energy-efficient surveillance system using wireless sensor networks [C]. Proceedings of the 2nd International Conference on Mobile Systems, Applications, and Services (MobiSys),2004, 270-283.
[90]M. Cardei and D. Du. Improving wireless sensor network lifetime through power aware organization [J], ACM Wireless Networks,2005,11(3):333-340.
[91]M. Cardei, M. Thai, Y. Li, et al. Energy-efficient target coverage in wireless sensor networks [C]. Proceedings of IEEE Conference on Computer Communications (INFOCOM),2005,1974-1986.
[92]A. Sen, N. Das, L. Zhou, et al. Coverage problem for sensors embedded in temperature sensitive environments [C]. Proceedings of the 4th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON),2007,520-529.
[93]Y. Cai, W. Lou, M. Li, et al. Target-oriented scheduling in directional sensor networks [C]. Proceedings of IEEE Conference on Computer Communications (INFOCOM),2007,1550-1558.
[94]任倩倩,李建中,高宏,等.传感器网络中一种基于两阶段睡眠调度的目标跟踪协议[J].计算机学报,2009,32(10)：1971-1979.
[95]J. Jeong, T. Hwang, T. He, et al. MCTA:target tracking algorithm based on minimal contour in wireless sensor networks [C]. Proceedings of IEEE Conference on Computer Communications (INFOCOM), Alaska, USA,2007, 2371-2375.
[96]孙晓艳,李建东,黄鹏宇,等.距离加权的二进制传感器网络目标跟踪算法[J].通信学报,2010,31(12)：140-146.
[97]G. Wang, M. Bhuiyan, and L. Zhang. Two-level cooperative and energy-efficient tracking algorithm in wireless sensor networks [J]. Wiley's Concurrency and Computation:Practice & Experience,2010,22(4):518-537.
[98]X. Zhang. Adaptive control and reconfiguration of mobile wireless sensor networks for dynamic multi-target tracking [J]. IEEE Transaction on Automatic Control,2011,56(10):2429-2444.
[99]K. Punithakumar, T. Kirubarajan, and A. Sinha. Multiple-model probability hypothesis density filter for tracking maneuvering targets [J]. IEEE Transactions on Aerospace and Electronic Systems,2008,44(1):87-98.
[100]H. She, Z. Lu, and A. Jantsch, et al. Stochastic coverage in event-driven sensor networks [C]. Proceedings of IEEE 22nd International Symposium on Personal Indoor and Mobile Radio Communications (PIMRC),2011,915-919.
[101]Y. Jin, J. Y. Jo, L. Wang, et al. ECCRA:an energy-efficient coverage and connectivity preserving routing algorithm under border effects in wireless sensor networks [J]. Computer Communications,2008,31(10):2398-2407.
[102]J. Harada, S. Shioda, and H. Saito. Path coverage property of randomly deployed sensor networks with finite communication ranges [C]. Proceedings of IEEE International Conference on Communications (ICC),2008,2221-2227.
[103]A. Ahmed, K. Yasumoto, Y. Yamauchi, et al. Distance and time based node selection for probabilistic coverage in People-centric sensing [C]. Proceedings of the 8th Annual IEEE Communications Society Conference on Sensor, Mesh and Ad Hoc Communications and Networks (SECON),2011,134-142.
[104]P. Wan and C. Yi. Coverage by randomly deployed wireless sensor networks [J]. IEEE/ACM Transactions on Networking,2006,14(SI):2658-2669.
[105]W. Zhang and C. Zhang. Sensor placement for grid coverage with probability mode [C]. Proceedings of International Conference on Computational Intelligence and Software Engineering (CiSE),2010,1-4.
[106]O. Rahman, A. Razzaque, and C. Hong. Probabilistic sensor deployment in wireless sensor network:a new approach [C]. Proceedings of the International Conference on Advanced Communication Technology,2007,1419-1422.
[107]F. Li, R. Raskar, and A. Lippman. Analysis on probabilistic view coverage for image sensing-a geometric approach [C], Proceedings of IEEE International Performance, Computing and Communications Conference,2008,271-280.
[108]M.D. Penrose. On к-connectivity for a geometric random graph [J]. Wiley Random Structure and Algorithms,1999,15(2):145-164.
[109]O. Ocakoglu and O. Ercetin. Energy efficient random sleep-awake schedule design [J]. Communications Letter, IEEE,2006,10(7):528-530.
[110]O. Omeni, A. Wong, and A. J. Burdett, et al. Energy efficient medium access protocol for wireless medical body area sensor networks [J]. IEEE Transactions on Biomedical Circuits and Systems.2008,2(4):251-259.
[111]A. Oka and L. Lampe. Energy efficient distributed filtering with wireless sensor networks [J]. IEEE Transactions on Signal Processing,2008,56(5):2062-2075.
[112]T. Park, D. Kim, and S. Jang, et al. Energy efficient and seamless data collection with mobile sinks in massive sensor networks [C]. Proceedings of IEEE International Symposium on Parallel & Distributed Processing,2009,1-8.
[113]S. Rashwand, J. Misic, V. Misic, et al. A novel asynchronous, energy efficient, low transmission delay MAC protocol for wireless sensor networks [C]. Proceedings of the 29th IEEE International Conference on Distributed Computing Systems (ICDCS) workshops,2009,186-193.
[114]J. Ma, W. Lou, Y. Wu, et al. Energy efficient TDMA sleep scheduling in wireless sensor networks [C]. Proceedings of IEEE Conference on Computer Communications (INFOCOM),2009,630-638.
[115]W. Ke, B. Liu, and M. Tsai. Efficient algorithm for constructing minimum size wireless sensor networks to fully cover critical square grids [J]. IEEE Transactions on Wireless Communications,2011,10(4):1154-1164.
[116]J. Wang and N. Zhang. Efficient point coverage in wireless sensor network [J]. Journal of Combinatorial Optimization,2006; 11(3):291-304.
[117]D. Dong, X. Liao, K. Liu, et al. Distributed coverage in wireless Ad hoc and sensor networks by topological graph approaches [J]. IEEE Transactions on Computers,2011,61(10):1417-1428.
[118]Y. Xiao, H. Chen, K. Wu, et al. Coverage and detection of a randomized scheduling algorithm in wireless sensor networks [J]. IEEE Transactions on Computers,2010,59(4):507-521.
[119]MICA2 Mote, http://www.xbow.com.cn/wsn/pdf/MICA2.pdf.
[120]M. Kandemir, P. Banerjee, A. Choudhary, et al. Static and dynamic locality optimizations using integer linear programming [J]. IEEE Transactions on Parallel and Distributed Systems,2001,12(9):922-941.
[121]M. Taghhavi, and P. Siegel. Adaptive methods for linear programming decoding [J]. IEEE Transactions on Information Theory,2008,54(12):5396-5410.
[122]B. Gou. Optimal placement of PMUs by integer linear programming [J]. IEEE Transactions on Power Systems,2008,23(3):1525-1526.
[123]T. Abdelzaher, T. He, and J. Stankovic. Feedback control of data aggregation in sensor networks [C], Proceedings of the 43rd IEEE Conference on Decision and Control,2004,1490-1495.
[124]K. Akkaya and M. Younis. A survey of routing protocols in wireless sensor networks [J]. Ad Hoc Networks,2005,3(3):325-349.
[125]H. Sanli, R. Poorrnachandran, H. Cam. Collaborative two-level task scheduling for wireless sensor nodes with multiple sensing units [C]. Proceedings of the 2nd Annual IEEE Communications Society Conference on Sensor and Ad Hoc Communications and Networks (SCEON),2005,350-361.
[126]K. Shih, H. Chen, C. Chou, et al. On target coverage in wireless heterogeneous sensor networks with multiple sensing units [J]. Journal of Network and Computer Applications,2009,32(4):866-877.
[127]C. Vu, S. Gao, W. Deshmukh, et al. Distributed energy-efficient scheduling approach for k-coverage in wireless sensor networks [C]. Proceedings of Military Communications Conference (MilCom),2006,1-7.
[128]W. Ke, B. Liu, and M. Tsai. Efficient algorithm for constructing minimum size wireless sensor networks to fully cover critical square grids [J]. IEEE Transaction on Wireless Communications,2011,10(4):1154-1164.
[129]J. Wang and N. Zhang. Efficient point coverage in wireless sensor networks [J]. Journal of Combinatorial Optimization,2006,11(3):291-304.
[130]A. Capone, M. Cesana, D. Donno, et al. Deploying multiple intercounnected gateways in heterogeneous wireless sensor networks:an optimization approach [J]. Computer Communications,2010,33(10):1151-1161.
[131]T. Shu and M. Krunz. Coverage-time optimization for clustered wireless sensor networks:a power-balancing approach [J]. IEEE/ACM Transactions on Networks, 2010,18(1):202-215.
[132]G Aloor and L. Jacob. Distributed wireless sensor network localization using stochastic proximity embedding [J]. Computer Communications,2010,33(6): 745-755.
[133]F. Ding, G Song, K. Yin, et al. A GPS-enabled wireless sensor network for monitoring radioactive materials [J]. Sensors and Actuators A:Physical,2009, 155(1):210-215.
[134]H. Song, S. Zhu, and G Cao. Attack-resilient time synchronization for wireless sensor network [J]. Ad Hoc Networks,2007,5(1):112-125.
[135]W. Heinzelman, A. Chandrakasan, and H. Balakrishnan. An application specific protocol architecture for wireless microsensor networks [J]. IEEE Transactions on Wireless Communications,2002,1(4):660-670.
[136]D. Kumar, T. Aseri, and R. Patel. EEHC:energy efficient heterogeneous clustered scheme for wireless sensor networks [J]. Computer Communications,2009,32(4): 662-667.
[137]N. Bouabdallah, M. Rivero-Angeles, and B. Sericola. Continuous monitoring using event-driven reporting for cluster-based wireless sensor networks [J]. IEEE Transactions on Vehicular Technology,2009,58(7):3460-3479.
[138]S. Yang, F. Dai, M. Cardei, et al. On connected multiple point coverage in wireless sensor networks [J], International Journal of Wireless Information Networks,2006,13(4):289-301.
[139]H. Liu, P. Wan, and X. Jia. Maximal lifetime scheduling for sensor surveillance system with k sensors to one target [J]. IEEE Transactions on Parallel and Distributed Systems,2006,17(12):1526-1536.
[140]H. Liu, P. Wan, and X. Jia. Maximal lifetime scheduling for k to 1 sensor-target surveillance networks [J]. Computer Networks,2006,50(15):2839-2854.
[141]陆克中,孙宏元.无线传感器网络最小覆盖集的贪婪近似算法[J].软件学报,2010,21(10)：2656-2665.
[142]P. Hall, Introduction to the Theory of Coverage Processes [M]. John Wiley & Sons Inc.,1998.
[143]X. Wang, G. Xing, Y. Zhang, et al. Integrated coverage and connectivity configuration in wireless sensor networks [C]. Proceedings of the ACM Conference on Embedded Networked Sensor Systems (SenSys),2003,28-39.
[144]G. Xing, X. Wang, Y. Zhang, et al. Integrated coverage and connectivity configuration for energy conservation in sensor networks [J]. ACM Transactions on Sensor Networks (TOSN),2005,1(1):36-72.
[145]王换招,董贝,罗韩梅,等.基于k覆盖保证的异构传感器网络节点调度策略[J].西安大学学报,2008,42(8)：940-945.
[146]Q. Zhao and M. Gurusamy. Connected k-target coverage problem in wireless sensor networks with different observation scenarios [J]. Computer Networks, 2008,52(11):2205-2220.
[147]B. Bela. The art of mathematics:coffee time in Memphis [M]. London: Cambridge University Press,2006.
[148]A. Chen, T. Lai, and D. Xuan. Measuring and guaranteeing quality of barrier coverage for general belts with wireless sensors [J]. IEEE Transactions on Sensor Networks (TOSN),2010, Vol.6, No.1,31 pages. DOI:10.1145/1653760.1653762.
[149]L. Li, B. Zhang, X. Shen, et al. A study on the weak barrier coverage problem in wireless sensor networks [J]. Computer Networks,2011,55(3):711-721.
[150]O. Elizabeth, G. Wang, M. Guo, et al. RARE:an energy-efficient target tracking protocol for wireless sensor networks [C]. Proceedings of the International Conference on Parallel Processing Workshops,2007,76-81.
[151]J. Lee, K. Cho, S. Lee, et al. Distributed and energy-efficient target localization and tracking in wireless sensor networks [J]. Journal of Computer Communications,2006,29(13-14):2494-2505.
[152]W. Zhang and G. Cao. DCTC:dynamic convey tree-based collaboration for target tracking in sensor networks [J]. IEEE Transactions on Wireless Comunications, 2004,11(5):1689-1701.
[153]Y. Xu, J. Heideman, and D. Estrin. Geography-informed energy conservation for Ad-hoc routing [C]. Proceedings of the 7th Annual International Conference on Mobile Computing and Networking (MobiCom),2001,70-84.
[154]J. Bruck, J. Gao, and A. Jiang. Localization and routing in sensor networks by local angle information [J]. ACM Transactions on Sensor Networks (TOSN),2009, 5(1):1-31.
[155]OMNET++. http://www.omnetpp.org/