Wireless/Mobile Systems
Real-time Communications over the IEEE 802.11

Past work at Penn includes a software-based contention-free token-bus protocol built on top of the IEEE 802.11 MAC protocol that provides medium access delay and bandwidth guarantees to real-time traffic. The protocol allows prioritized transmission requests and performs dynamic admission control. It can also adapt dynamically to the varying system load so as to provide an efficient bandwidth usage. It is the first link layer protocol over the widely used IEEE 802.11 MAC protocol that provides QoS guarantees to real-time multimedia traffic without resorting to any hardware modifications. Performance evaluation shows that the protocol satisfies the access delay and bandwidth requirements of real-time traffic at the expense of longer average delays and lower throughput of non-real-time traffic.

Mobile Robots- Senior Design Projects

In the past, we worked with three groups of senior undergraduates to develop a mobile robotics platform for experimenting with real-time java. Each robot had a wireless camera and radio data link which allowed it to be remotely controlled or monitored as well as an on-board processor.

Maria Adamou, Sanjeev Khanna, Insup Lee, Insik Shin, Shiu Zhou, "Fair Real-time Traffic Scheduling over A Wireless LAN," Proceedings of the 22nd IEEE Real-Time Systems Symposium, RTSS 2001, London, UK, December 3-6, 2001. Slides
Maria Adamou, Insup Lee, Insik Shin, "An Engergy Efficient Real-Time Medium Access Control Protocol for Wireless Ad-Hoc Networks," Proceedings of Work-In-Progress (WIP) Session in the 22nd IEEE Real-Time Systems Symposium, RTSS 2001, London, UK, December 5, 2001.