Opportunistic Scheduling for Wireless Data Networks of Embedded Devices
Speaker: Dr Amoakoh Gyasi-Agyei, Central QLD Univiversity
When: 2004-12-02 15:30:00
Venue: 78-622
Host: Prof Neil Bergmann
Abstract:The performance of every network with a shared resource hinges on
the MAC (medium access technique) used, and more so for wireless
(multihop) networks. Traffic scheduling is one of the methods used
by MAC to coordinate transmissions of multiple users. Traditional
MAC design views channel fading as a problem and combat it via
sophisticated methods (e.g. power control, interleaving, antenna
diversity, equalization, channel coding, frequency hopping). These
sophisticated processes rather reduce throughput; increase system
complexity, processing delay and energy constraints on handheld
devices. Opportunistic scheduling (OS) is a modern view of multiuser
communications over networks with fading channels, whereby the
channel randomness is exploited to enhance spectral efficiency and
reduce system complexity.
OS suspends transmitting a packet to a user/MH until its link
quality hits near its peak (i.e. clear channel) with highly probable
correct reception at highest bit rate. Power dissipation is a
constraint in every handheld wireless embedded device, and optimized
traffic scheduling can be designed to save energy and prolong
battery life.
In this seminar, we first motivate the notion of multiuser diversity
based OS, and outline some key design challenges. We then cite an
application of OS in a practical wireless data network. We discuss a
weighted fair OS providing differentiated QoS in wireless data
networks, while maximizing throughput (bandwidth efficiency) and
limiting delays. We then show some simulation results. Finally, we
discuss how this new view of communications is poised to
revolutionize the overall cross-layer design of future wireless data
networks at physical, networking and architectural levels.
Biography:Dr Amoakoh Gyasi-Agyei obtained a PhD from Adelaide University, MSc
from Chalmers University of Technology, Sweden, and a bachelor
degree from TUHH Hamburg in Germany. Amoakoh is currently a Lecturer
in Communications & Electronic Engineering at Central QLD Univ,
where he's also the Program Advisor for Electrical Engineering
undergraduate programs and the staff in charge of
Telecommunications. Prior to his PhD candidature at Adelaide
University, Amoakoh worked as a Research Scientist in Nokia
sponsored R&D Group at Helsinki University of Technology Finland in
Telecommunication and Computer Networking for 3 years and worked
with Ericsson Mobile Data Design AB in Sweden in Mobile Data
Networking. He was a Visiting R&D Engineer with the National
University of Singapore's Telecommunications Group in 2000/2001 and
with the Radio Network Design Laboratory of S. Koreans' Information
& Communications University in 2002. His PhD work was partly
sponsored by Australians' Smart Internet Technology CRC, and was the
first PhD graduate from the group. He recently consulted with BHP
Billiton Mine in Central QLD in two-way repeater radio systems. As
an undergraduate student at TUHH in Germany, Amoakoh worked for 3
years as an engineering assistant under Prof Ackermann and Prof
Schunemann. He worked on a cargo ship in 1994 as an assistant ship's
electrician. Amoakoh constantly reviews papers for IEEE Network and
IEEE Communucations Letters Journals and International Conferences
on Wireless Networking and Computer Communications. He was an
invited speaker at ICCIT'99 international conference on the topic
"mobile data networking using DECT radio technology". He was an
invited speaker at SIT CRC PhD Student Workshop, Sydney 2003 on the
topic: "Surviving a PhD: my retrospective". He's a member of both
the IEE and the IEEE. He has been nominated Treasurer of IEEE QLD
Section for 2005.
Type: ITEE Seminar
Contact:Prof Neil Bergmann, seminar host (n.bergmann@itee.uq.edu.au)
or Guido Governatori (ITEE seminar co-ordinator)
(guido@itee.uq.edu.au)