Walter Sun received a Bach. of Elec. Eng. degree from the Georgia Institute of Technology in Atlanta, GA in June 1995. He received a Sc.M. degree in February 1997 at the Massachusetts Institute of Technology in the Speech Communication Group within the Research Lab of Electronics. After a leave of absence to work in industry, he returned Sept 2002 and is currently pursuing a Ph.D. degree in Elec. Eng. at M.I.T. as a research assistant in the Stochastic Systems Group within the Laboratory for Information and Decision Systems.