DISSERTATION DEFENSE Department of Computer Science and Engineering, University of South Carolina Emerging Wireless Sensor Networks in Intertidal Zones and for Tracking Targets Candidate: Miao Xu Advisor: Dr. Wenyuan Xu Date: Monday, March 23, 2015 Time: 10:00am Place: Swearingen (3A00, Deans Conference Room) Abstract Wireless sensor networks (WSNs), which consist of a large number of low-power, low-cost sensor nodes, are promising because they can continuously and remotely monitor our surroundings with few human involvements. For example, we have witnessed sensor applications that monitor the habitat environment of wild animals or monitor the health condition of infrastructures. These traditional WSNs are typically used as monitoring applications and deployed at various terrestrials. In this dissertation, however, we examine two different types of 0emerging sensor applications, which are WSNs deployed in intertidal zones (IT-WSNs) and WSNs deployed for tracking targets (TT-WSNs). Alternately submerged and laid bare by tides, the wireless channels in IT-WSNs are intermittent and could be unavailable up to 24 hours, which makes IT-WSNs unique compared with terrestrial WSNs. In the first part of this dissertation, we examine some problems that are caused by the influence of tides. First, we study the time synchronization problem in IT-WSNs. Due to the intermittent wireless channels, traditional resynchronization schemes cannot be directly applied to IT-WSNs. To prolong the resynchronization interval, we propose a temperature-aware compensation scheme that continuously adjusts the clock locally without any resynchronization messages. Second, we examine the low-power embedded systems for the sensor nodes in IT-WSNs. Battery powered, the nodes in WSNs typically employ duty-cycling schemes to reduce the average power. To further reduce the power consumption, we study the channel-aware features for radio transceivers given that the channels are intermittent. We also propose to develop an automation platform that automatically finds the most power saving configuration of IO pins. Finally, we investigate environment-aware MAC protocols in Part I. Many existing WSNs are proposed for monitoring physical phenomena, but few of them study the applications for tracking targets. In the second part of this dissertation, we examine the TT-WSNs that are deployed for tracking a target such as some endangered animals. Since the data exchanged in TT-WSNs are typically associated with the target's location information, the data privacy is important to the users. In addition, once deployed, the networks are typically left unattended, which makes the privacy issue even more challenging. Although many cryptography-based solutions have been proposed to solve the problem, we are interested in non-cryptography schemes because cryptography-based methods cannot cope with node compromise. Based on the observation that message content is important in TT-WSNs, we propose a content-aware data dissemination scheme for TT-WSNs to achieve better data privacy and higher data availability with less energy cost.