| Wireless sensor networks have always been a hot topic in the network research community since they have a variety of military and civil applications such as environmental detections, health applications, disaster recoveries, etc. Due to its flexible deployment, it is believed that a wireless sensor network must be a vital part of the next generation networks. Energy sources in wireless sensor networks are very limited since the wireless devices are small and battery-powered. During my Ph.D program, I have studied how to achieve energy efficient routing and broadcasting since they are the two common operations in wireless networks. |