Alhussein Abouzeid Research:




Systems: Communication Networks; Wireless Ad Hoc and Sensor Networks; Peer-to-Peer Networks.

Applied Theory: Stochastic Processes; Algorithm and Protocol Complexity; Multi-layer Optimization; Information Theory; Queuing Theory.


Project "Coverage": Energy Efficient Coverage using Wireless Sensor Networks


Sensing coverage is a fundamental problem in wireless sensor networks. It reflects how well the environment is monitored, and serves as a basis for applications such as physical phenomenon or target detection, classification and tracking. Due to the increasing diversity of sensor network applications, the concept of sensing coverage includes a growing range of interpretations.

In this work, we consider coverage problems involving two new characteristics of emerging visual as well as mobile sensor networks. The solution approach to both problems utilizes tools from optimization theory and algorithmic complexity.

In the first problem, we study power-efficient coverage by randomly deployed directional sensors with tunable orientations on a set of discrete targets. This problem arises, for example, in networks of visual surveillance sensors (e.g. on-chip cameras with finite field of view). We consider centralized as well as distributed solutions of this problem, and evaluate the properties of the proposed solutions and algorithms in terms of providing coverage (minimizing the number of targets missed) while maximizing network lifetime through mathematical analysis and extensive simulations. Furthermore, the topic has interesting synergies with the research interest of collaborators in the computer vision group from ECSE and CS.

In the second problem, we consider a network of sensors whose mobility is controlled by the designer (rather than random). The objective is to capture stochastic events appearing at points of interest with a minimum target quality. While mobile sensors cover more area over a period of time than the same number of stationary sensors, the quality of coverage achieved by mobile sensors depends on the velocity, mobility pattern and number of mobile sensors deployed and the dynamics of the phenomenon being sensed. This research considers the gains attained, if any, by mobile sensors over static sensors and the optimal motion strategies for mobile sensors. Applications of these results span a wide array of applications, from unmanned underwater vehicles to border control. Synergies also exist here with the robotics group.

We also considered the effect of packet loss on the quality of coverage in sensor networks. This is important since packet loss can not be avoided due to the use of wireless links. This issue has been considered in the context of a network of geotechnical sensors for monitoring landslides developed in collaboration with the Civil Engineering department (through NSF funding).




              WiOpt06 slides: .pps, .pdf

              Mobicom06 slides: .pps, .pdf


Key Publications:


          J. Ai and A. A. Abouzeid, “Coverage by Directional Sensors in Randomly Deployed Wireless Sensor Networks,” Journal of Combinatorial Optimization, Special Issue on Network Applications, vol. 11, no. 1, pp. 21-24, February 2006. (Conference version in WiOpt 2006.)

          N. Bisnik, A.A. Abouzeid and V. Isler, “Stochastic Event Capture Subject to a Quality Metric,” IEEE Transactions on Robotics, conditionally accepted in November 2006. (Conference version in ACM MobiCom 2006).

          N. Bisnik, A.A. Abouzeid and V. Isler, “Stochastic Event Capture in Mobile Sensor Networks Subject to a Quality Metric,” Proceedings of the Twelfth Annual International Conference on Mobile Computing and Networking (MobiCom 2006), pp. 89-109, Los Angeles, California, USA, September 24-29, 2006.