Dedication

and my beloved wife Ling-chih ii Acknowledgments Pursuing a Ph.D. at USC has been the most rewarding experience in my life. For the most of it, I thank my advisor Michael J. Neely. Apart from being a great role model over the years, Mike urges me to boldly pursue difficult research problems, and provides me with generous guidance and support to develop elegant solutions. I thank Mike for giving me the opportunity to struggle, nurturing me as an independent researcher, and showing me the joy of doing good research. I have learned about myself and research more than I expected when I first arrived at USC, and I am forever indebted to Mike for this. I thank Bhaskar Krishnamachari and Qing Zhao for introducing their work on cog-nitive radio networks to me during a seminar at USC. Their work gives me a brand new perspective on doing stochastic optimization over Markovian channels and, more generally, over frame-based systems. Such a paradigm shift leads to a large part of this dissertation. I appreciate Bhaskar Krishnamachari, Giuseppe Caire, Rahul Jain, and Amy R. Ward for taking their time serving on both my qual exam and defense exam committee, and I thank them for their valuable comments. I thank Gerrielyn Ramos, Anita Fung, Mayumi Thrasher, and Milly Montenegro for their generous administrative support that makes my life hassle-free at the Communication Sciences Institute. Working at “the 5th floor ” of EEB is memorable because of my friends and officemate