not only for their insightful guidance, patience, support and invaluable assistance throughout this work, but also for their help in my daily life over the past three years. I would also like to show my gratitude to Marco and Azzurra for their help in reviewing my thesis, as well as Marco Crepaldi for his technical advice and help during my circuit design work. I have received much help and support from numerous past and present members of the UWB group, including Alessandro, Stefano, Matteo, Paolo, Franscesco and Antonio. I want to say thank you so much guys, I am so happy to work with you. My appreciation extends to all the students in the VLSI Lab, Awais, Ruiyu, Juanchi, Manoj, Ali, Azhar, Abduwali and Matteo who kept me company with their discussions and cheerful chats during the coffee break, and the rest of my fellows whose names are missing due to space limitation. Moreover, I would like to thank all my lovely friends, especially my roommates and "lunch group" members, for their companion, encouragement and support. Finally, I would like to thank my family for their unconditional support and love along these years. Thanks Mom, thanks Dad, your support means so much to me. I have to say thank you to Yu Jian, for those moments of peace and well-being that only you can give me.