Select a calendar:
Filter August Events by Event Type:
Events for August 01, 2008
-
Exploiting Cooperative Diversity in Slotted ALOHA Random Access Networks
Fri, Aug 01, 2008 @ 11:00 AM - 12:00 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
Speaker: Y.-W. Peter Hong
National Tsing Hua University, TaiwanAbstract:
In a cooperative system, each user exploits spatial diversity by transmitting their packets through multiple
relaying paths provided by their cooperative partners. Most works in the literature on cooperative
communications focus on the physical layer aspects such as coding, modulation, transceiver signal processing
etc. In this talk, we will discuss the advantages of user cooperation from a MAC layer perspective and devise
queueing strategies to exploit the cooperative diversity gains in a random access network. Specifically, we
propose two queueing strategies for the cooperative system and study their respective stability regions. We
show that both schemes outperform the case with no cooperation, especially when one user has a better channel
than the other. We then extend our system to networks that consist of multiple cooperating pairs and study the
stability of the finite-user cooperative system. By treating each cooperative pair as a transmission entity, we
derive inner bounds for the finite-user stability region and propose a ranking system to characterize the entities'
relative tendency of being stable (or unstable).Biography:
Y.-W. Peter Hong received his B.S. degree in Electrical Engineering from National Taiwan University, Taipei,
Taiwan, in 1999, and his Ph.D. degree in Electrical Engineering from Cornell University, Ithaca, NY, in 2005.
In 2005, he joined the Institute of Communications Engineering/Department of Electrical Engineering in
National Tsing Hua University, Hsinchu, Taiwan, where he is currently an Assistant Professor. His research is
focused on cooperative communications, distributed signal processing for sensor networks, and PHY-MAC
cross-layer designs for next generation wireless networks. He received the best paper award among unclassified
papers in MILCOM 2005 and the best paper award for young authors from the IEEE IT/COM Society
Taipei/Tainan chapter in 2005. He is a co-editor (along with A. Swami, Q. Zhao and L. Tong) of the book
entitled "Wireless Sensor Networks: Signal Processing and Communications Perspectives" (John-Wiley, 2007).Host: Professor C.-C. Jay KuoLocation: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: Talyia Veal
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor. -
Utilizing Topological Codes for Fault-Tolerant Universal Quantum Computing
Fri, Aug 01, 2008 @ 02:00 PM - 03:30 PM
Ming Hsieh Department of Electrical and Computer Engineering
Conferences, Lectures, & Seminars
SPEAKER: Jim Harrington
Los Alamos National LaboratoryABSTRACT: Kitaev's surface codes have the attractive property of requiring only local stabilizer measurements, while all logical error operators stretch between boundaries (or form non-trivial loops, in the case of a torus). This gives rise to an exponential suppression in logical errors as a function of code size, under an independent error model. I will present a history of the ideas connecting these surface codes to cluster states, which led to Raussendorf's suggested architecture of a single two-dimensional array of qubits for fault-tolerant universal quantum computation, with an estimated error threshold above 0.7%. I also plan to present very preliminary analysis on the quantum memory threshold for one of the topological color codes introduced by Bombin and Martin-Delgado.BIOGRAPHY: Jim Harrington studied quantum error correction in John Preskill's group at Caltech and received his Ph.D. in 2004. Jim came to Los Alamos National Laboratory (LANL) as an Intelligence Community Postdoctoral Fellow to work primarily on security proofs and protocols for quantum key distribution. He is now a Technical Staff Member at LANL and continues to work on a variety of topics in quantum information security and quantum coding theory.HOST: Prof. Todd Brun, tbrun@usc.eduLocation: Seaver Science Library (SSL) - 150
Audiences: Everyone Is Invited
Contact: Gerrielyn Ramos
This event is open to all eligible individuals. USC Viterbi operates all of its activities consistent with the University's Notice of Non-Discrimination. Eligibility is not determined based on race, sex, ethnicity, sexual orientation, or any other prohibited factor.
