ECOQUAD: Energy-Conserving Quality-Aware Data Collection in Wireless Sensor Networks*

[Abstract]

Recent advances in signal processing, micro-electronics, and wireless communications have enabled the deployment of large-scale sensor networks for many applications such as habitat and wildlife monitoring. A wireless sensor network is typically constructed of a large number of sensor nodes which are battery powered. Thus, energy efficiency is a critical consideration in the design of such a network. While most existing studies have focused on reducing data communication in providing exact answers to user queries, this proposed research exploits the trade-off between data quality and communication cost to improve energy efficiency. We consider approximate queries with precision guarantees, which suffice the purpose of many sensor applications. Both one-shot queries and long-running queries will be studied. We propose a two-tier data collection architecture in support of various types of one-shot queries. Under this architecture, strategies for query processing and the issue of optimal precision setting will be examined. We will then extend our research to the more complex and challenging long-running aggregate queries, where the precision constraint of data aggregation will be partitioned and distributed to the sensor nodes involved. Precision allocation and distribution techniques for this unique problem will be developed. Finally, we plan to develop a testbed and a simulator to demonstrate, experiment, and evaluate the proposed techniques.

[Objectives]

The specific goals of this project are:

[Relevant Publications]

  1. X. Tang and J. Xu. "Adaptive Data Collection Strategies for Lifetime-Constrained Wireless Sensor Networks." IEEE Transactions on Parallel and Distributed Systems (TPDS), June 2008. [pdf]
  2. J. Xu, X. Tang, and W.-C. Lee. "A New Storage Scheme for Approximate Location Queries in Object Tracking Sensor Networks." IEEE Transactions on Parallel and Distributed Systems (TPDS), 19(2): 262-275, Feb. 2008. [pdf]
  3. X. Tang and J. Xu. "Optimizing Lifetime for Continuous Data Aggregation with Precision Guarantees in Wireless Sensor Networks." IEEE/ACM Transactions on Networking (ToN), August 2008. [pdf]
  4. M. Wu, J. Xu, X. Tang, and W.-C. Lee. "Top-k Monitoring in Wireless Sensor Networks." IEEE Transactions on Knowledge and Data Engineering (TKDE), 19(7): 962-976, July 2007. [pdf]
  5. M. Wu, J. Xu, and X. Tang. "Processing Precision-Constrained Queries in Wireless Sensor Networks." Proc. the 7th Int. Conf. on Mobile Data Management (MDM '06), Nara, Japan, May 2006. [pdf]
  6. X. Tang and J. Xu. "Extending Network Lifetime for Precision-Constrained Data Aggregation in Wireless Sensor Networks." Proc. the 25th IEEE INFOCOM '06, Barcelona, Spain, April 2006. [pdf]
  7. Y. Xu, W.-C. Lee, J. Xu, and G. Mitchel. "Processing Window Queries in Wireless Sensor Networks." Proc. the 22nd IEEE Int. Conf. on Data Engineering (ICDE '06), Atlanta, GA, April 2006. [pdf]
  8. M. Wu, J. Xu, X. Tang, and W.-C. Lee. "Monitoring Top-k Query in Wireless Sensor Networks." Proc. the 22nd IEEE Int. Conf. on Data Engineering (ICDE '06), Atlanta, GA, April 2006. (Poster paper [pdf].
  9. J. Xu, X. Tang, and W-C. Lee. "EASE: An Energy-Efficient In-Network Storage Scheme for Object Tracking in Sensor Networks." Proc. the 2nd IEEE Conf. on Sensor and Ad Hoc Communications and Networks (SECON '05), Santa Clara, CA, September 2005. [pdf]

* This project is supported by the Research Grants Council (RGC), Hong Kong SAR, China under Project No. HKBU211505. For further information, please contact Jianliang Xu.