Robust Coexistence of Multiple Frequency Hopped Networks

Date: Nov. 10 th
Time: 3:00 p.m.
Place: 112 Thatch Hall

Personal PhotoXiangqian Liu
Department of Electrical and Computer Engineering,
University of Louisville

Biography

Dr. Xiangqian (Shawn) Liu received the Ph.D. degree from the University of Minnesota in 2002, the M.S. degree from the University of Virginia in 1999, and the B.S. degree from Beijing Institute of Technology, all in Electrical Engineering. He is currently an assistant professor of Electrical and Computer Engineering at the University of Louisville. Dr. Liu's research interests are in the areas of wireless communications, sensor networks, and signal processing.

ABSTRACT

Robust Coexistence of Multiple Frequency Hopped Networks
Frequency hopping is widely used for radio transmissions in wireless communications. With the increasing deployment of wireless networks and devices on the unlicensed band, multiple frequency hopped (FH) networks are likely to coexist in a physical environment, especially in tactical operations, emergency situations, and dense populated areas. In such cases frequency collisions caused by neighboring devices can
become a major performance limiting factor. Most existing collision avoidance techniques are effective in dealing with static interferences, but not applicable to multiple FH networks, because the interfering channels are dynamically changing.

In this talk, we present a framework for robust coexistence of multiple FH networks. This includes a dual channel transmission technique with frequency diversity in the median access control (MAC) layer, and a signal processing technique for collision resolution in the physical layer. We systematically study the performance of the proposed methods, and validate analytical results by computer simulations. Applications
of this work include robust coexistence of Bluetooth piconets and WLAN, as well as interference mitigation and jamming rejection in tactical FH networks.