This thesis would not be possible if I did not have the help and advice of several people who contributed their valuable support in completion of this study. First of all, I would like to express my sincere appreciation and gratitude to my supervisor, Associate Professor Mao Kezhi for giving me an opportunity to pursue my interest in research work under his valuable guidance. He is not only a supervisor but also a warm hearted friend that I always can count on his support and help. It gives me immense pleasure to thank my mentor and co-supervisor, Doctor Yau Wei-Yun for his support, continuous guidance and astute criticism during this study. Nothing can gratify the invaluable time he generously dedicated to me despite his busy schedule. My special thanks go to my Thesis Advisory Committee members, Professor Huang Guangbin, Associate Professor Wang Han and Dr. Li Xiaoli for their invaluable guidance and encouragement throughout my research. Financial assistance provided by the Agency for Science, Technology and Research (A*STAR) in the form of Graduate Scholarship is thankfully acknowledgeable. I would like to express my gratitude to the staffs in Institute for Infocomm Research (I2R), Ms. Janice Lee Sze Min and Ms. Felicia Chew for their effort on my attachment matters. I cannot miss mentioning my home mates during last 4 years in Singapore, Amin Kianinejhad, Siavash Sakhavi, Hossein Dehghani Tafti and Ali Rajabipoor for making ii my life during Ph.D. a very memorable one. Also, I should mention my Iranian friends in Singapore, whom their moral supports were a great help during this candidature: