This Article 
 Bibliographic References 
 Add to: 
SenCar: An Energy-Efficient Data Gathering Mechanism for Large-Scale Multihop Sensor Networks
October 2007 (vol. 18 no. 10)
pp. 1476-1488
In this paper, we propose a new data gathering mechanism for large scale multihop sensor networks. A mobile data observer, called SenCar, which could be a mobile robot or a vehicle equipped with a powerful transceiver and battery, works like a mobile base station in the network. SenCar starts the data gathering tour periodically from the static data processing center, traverses the entire sensor network, gathers the data from sensors while moving, returns to the starting point, and finally uploads data to the data processing center. Unlike SenCar, sensors in the network are static, and can be made very simple and inexpensive. They upload sensed data to SenCar when SenCar moves close to them. Since sensors can only communicate with others within a very limited range, packets from some sensors may need multihop relays to reach SenCar. We first show that the moving path of SenCar can greatly affect network lifetime. We then present heuristic algorithms for planning the moving path/circle of SenCar and balancing traffic load in the network. We show that by driving SenCar along a better path and balancing the traffic load from sensors to SenCar, network lifetime can be prolonged significantly. Our moving planning algorithm can be used in both connected networks and disconnected networks. In addition, SenCar can avoid obstacles while moving. Our simulation results demonstrate that the proposed data gathering mechanism can prolong network lifetime significantly compared to a network which has only a static observer, or a network in which mobile observer can only move along straight lines.

[1] S. Chessa and P. Santi, “Crash Faults Identification in Wireless Sensor Networks,” Computer Comm., vol. 25, no. 14, pp. 1273-1282, 2002.
[2] L. Schwiebert, S.K.S. Gupta, and J. Weinmann, “Research Challenges in Wireless Networks of Biomedical Sensors,” Proc. ACM MobiCom, 2001.
[3] P. Juang, H. Oki, Y. Wang, M. Martonosi, L. Peh, and D. Rubenstein, “Energy-Efficient Computing for Wildlife Tracking: Design Tradeoffs and Early Experiences with Zebranet,” Proc. 10th Int'l Conf. Architectural Support for Programming Languages and Operating Systems (ASPLOS), 2002.
[4] T. Small and Z. Haas, “The Shared Wireless Infostation Model—A New Ad Hoc Networking Paradigm (or Where There Is a Whale, There Is a Way),” Proc. ACM MobiHoc, 2003.
[5] I. Vasilescu, K. Kotay, D. Rus, M. Dunbabin, and P. Corke, “Data Collection, Storage and Retrieval with an Underwater Sensor Network,” Proc. ACM Third Int'l Conf. Embedded Networked Sensor Systems (SenSys '05), 2005.
[6] G. Asada, T. Dong, F. Lin, G. Pottie, W. Kaiser, and H. Marcy, “Wireless Integrated Network Sensors: Low Power Systems on a Chip,” Proc. 25th European Solid State Circuits Conf., 1998.
[7] The Ultra Low Power Wireless Sensor Project, , 2004.
[8] W.R. Heinzelman, A. Chandrakasan, and H. Balakrishnan, “Energy-Efficient Communication Protocols for Wireless Microsensor Networks,” Proc. 33rd Ann. Hawaii Int'l Conf. System Sciences (HICSS), Jan. 2000.
[9] O. Younis and S. Fahmy, “Distributed Clustering in Ad Hoc Sensor Networks: A Hybrid, Energy-Efficient Approach,” Proc. IEEE INFOCOM, 2004.
[10] M. Ma, Z. Zhang, and Y. Yang, “Multi-Channel Polling in Multi-Hop Clusters of Hybrid Sensor Networks,” Proc. IEEE Global Telecomm. Conf. (GLOBECOM '05), Nov. 2005.
[11] A. Chakrabarty, A. Sabharwal, and B. Aazhang, “Using Predictable Observer Mobility for Power-Efficient Design of a Sensor Network,” Proc. Second Int'l Workshop Information Processing in Sensor Networks (IPSN '03), Apr. 2003.
[12] A. Pentland, R. Fletcher, and A. Hasson, “Daknet: Rethinking Connectivity in Developing Nations,” Computer, vol. 37, no. 1, pp.78-83, Jan. 2004.
[13] A.A. Somasundara, A. Ramamoorthy, and M.B. Srivastava, “Mobile Element Scheduling for Efficient Data Collection in Wireless Sensor Networks with Dynamic Deadlines,” Proc. 25th IEEE Real Time Systems Symp. (RTSS), Dec. 2004.
[14] D. Jea, A.A. Somasundara, and M.B. Srivastava, “Multiple Controlled Mobile Elements (Data Mules) for Data Collection in Sensor Networks,” Proc. First IEEE/ACM Int'l Conf. Distributed Computing in Sensor Systems (DCOSS '05), June 2005.
[15] W. Zhao, M. Ammar, and E. Zegura, “A Message Ferrying Approach for Data Delivery in Sparse Mobile Ad Hoc Networks,” Proc. ACM MobiHoc, 2004.
[16] J. Luo and J.-P. Hubaux, “Joint Mobility and Routing for Lifetime Elongation in Wireless Sensor Networks,” Proc. IEEE INFOCOM, 2005.
[17] R.C. Shah, S. Roy, S. Jain, and W. Brunette, “Data MULEs: Modeling a Three-Tier Architecture for Sparse Sensor Networks,” Proc. First IEEE Workshop Sensor Network Protocols and Applications (SNPA '03), 2003.
[18] S. Jain, R.C. Shah, W. Brunette, G. Borriello, and S. Roy, “Exploiting Mobility for Energy-Efficient Data Collection in Wireless Sensor Networks,” ACM/Kluwer Mobile Networks and Applications (MONET), 2005.
[19] A. Kansal, A. Somasundara, D. Jea, M. Srivastava, and D. Estrin, “Intelligent Fluid Infrastructure for Embedded Networks,” Proc. Second ACM Int'l Conf. Mobile Systems, Applications and Services (MobiSys '04), 2004.
[20] J.H. Chang and L. Tassiulas, “Energy Conserving Routing in Wireless Ad Hoc Networks,” Proc. IEEE INFOCOM, 2000.
[21] A. Bogdanov, E. Maneva, and S. Riesenfeld, “Power-Aware Base Station Positioning for Sensor Networks,” Proc. IEEE INFOCOM, 2004.
[22] Z. Zhang, M. Ma, and Y. Yang, “Energy Efficient Multi-Hop Polling in Clusters of Two-Layered Heterogeneous Sensor Networks,” Proc. 19th IEEE Int'l Parallel and Distributed Processing Symp. (IPDPS), 2005.
[23] C. Guo, L.C. Zhong, and J.M. Rabaey, “Low-Power Distributed MAC for Ad Hoc Sensor Radio Networks,” IEEE Global Telecomm. Conf. (GLOBECOM '01), 2001.
[24] R.K. Ahuja, T.L. Magnanti, and J.B. Orlin, Network Flows: Theory, Algorithms and Applications. Prentice Hall, 1993.
[25] Understanding GPS: Principles and Applications, E.D. Kaplan, ed. Artech House, 1996.
[26] S. Capkun, M. Hamdi, and J.P. Hubaux, “GPS-Free Positioning in Mobile Ad-Hoc Networks,” Proc. 34th Hawaii Int'l Conf. System Sciences (HICSS '01), Jan. 2001.
[27] S.S. Skiena, Algorithm Design Manual, pp. 319-322. Springer-Verlag, 1997.
[28] Concorde TSP Solver, http://www.tsp.gatech.educoncorde.html, 2006.

Index Terms:
SenCar, wireless sensor networks, data gathering, load balancing
Ming Ma, Yuanyuan Yang, "SenCar: An Energy-Efficient Data Gathering Mechanism for Large-Scale Multihop Sensor Networks," IEEE Transactions on Parallel and Distributed Systems, vol. 18, no. 10, pp. 1476-1488, Oct. 2007, doi:10.1109/TPDS.2007.1070
Usage of this product signifies your acceptance of the Terms of Use.