Phoebus Chen

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In this paper, we propose and demonstrate a novel wireless camera network system, called CITRIC. The core component of this system is a new hardware platform that integrates a camera, a frequency-scalable (up to 624 MHz) CPU, 16MB FLASH, and 64MB RAM onto a single device. The device then connects with a standard sensor network mote to form a camera mote.(More)
This paper considers the problem of pursuit evasion games (PEGs), where a group of pursuers is required to chase and capture a group of evaders in minimum time with the aid of a sensor network. We assume that a sensor network is previously deployed and provides global observability of the surveillance region, allowing an optimal pursuit policy. While sensor(More)
Many of the routing protocols that have been designed for wireless ad-hoc networks focus on energy-efficiency and guaranteeing high throughput in a non-adversarial setting. However, given that ad-hoc and sensor networks are deployed and left unattended for long periods of time, it is crucial to design secure routing protocols for these networks. Over the(More)
On August 30, 2005, we successfully demonstrated a large-scale, real-time, surveillance and control application on a wireless sensor network. The task was to track multiple human targets walking through a 5041 square meter sensor field and dispatch simulated pursuers to capture them. We employed a multi-target tracking algorithm that was a combination of a(More)
On August 30, 2005, we successfully demonstrated a large-scale, real-time, surveillance and control application on a wireless sensor network. The task was to track multiple human targets walking through a 5041 square meter sensor field and dispatch simulated pursuers to capture them. We employed a multi-target tracking algorithm that was a combination of a(More)
There has been a recent rise in interest in building networked control systems over a wireless network, whether they be for robot navigation, multi-robot systems, or traditional industrial automation. The wireless networks in these systems must deliver packets between the controller and the actuators/sensors reliably and with low latency. Furthermore, they(More)
Multiple-target tracking is a representative real-time application of sensor networks as it exhibits different aspects of sensor networks such as event detection, sensor information fusion, multi-hop communication, sensor management and real-time decision making. The task of tracking multiple objects in a sensor network is challenging due to constraints on(More)
Several emerging classes of applications that run over wireless networks have a need for mathematical models and tools to systematically characterize the reliability of the network. We propose two metrics for measuring the reliability of wireless mesh routing topologies, one for flooding and one for unicast routing. The Flooding Path Probability (FPP)(More)
Smart camera networks have recently emerged as a new class of sensor network infrastructure that is capable of supporting high-power in-network signal processing and enabling a wide range of applications. In this article, we provide an exposition of our efforts to build a low-bandwidth wireless camera network platform, called CITRIC, and its applications in(More)
While the traditional wireless sensor networks (WSN) consist of low-bandwidth sensors with limited capabilities, e.g., acoustic, vibration, and infrared sensors, camera sensor networks can provide visual verification, in-depth situational awareness, recognition, and other capabilities ([1], and references therein).