Monday, April 10, 2000
2:15 PM (refreshments 2:00)
Grier Room, Room 34-401B
EECS Special Seminar
Abstract
In recent years, advances in energy-efficient design and wireless technologies have enabled exciting new applications for wireless devices. These applications span a wide range, including real-time and streaming video and audio delivery, remote monitoring using networked microsensors, personal medical monitoring, and home networking of everyday appliances. While these applications require high performance from the network, they suffer from resource constraints that do not appear in more traditional wired computing environments. In particular, wireless spectrum is scarce, often limiting the bandwidth available to applications and making the channel error-prone, and the nodes are battery-operated, often limiting available energy.
I will make the case that this harsh environment with severe resource constraints requires an application-specific protocol architecture, rather than the traditional layered approach, to obtain the best possible performance. I support this claim using detailed case studies on microsensor networks and wireless video delivery. In the first study, I develop an architecture for remote microsensor networks that combines the ideas of energy-efficient cluster-based routing and media access together with application-specific beamforming to achieve good performance in terms of system lifetime, latency, and application-perceived quality. This approach improves system lifetime by an order of magnitude compared to traditional approaches when the node energy is limited. For the second study, I develop an unequal error-correction scheme for MPEG-4 compressed video delivery that adapts the level of correction applied to portions of a packet to the degree of importance of the corresponding bits. This approach obtains better application-level performance than current approaches for the same amount of transmission bandwidth.
|
Modified: Apr 4, 2000|
Current events|
Your comments
and inquiries are welcome.