Data Gathering and Fusion in Sensor Networks
Wei‐Peng Chen, Jennifer C. Hou · 2005
Data gathering is one of the most important tasks in sensor networks. In most data gathering applications, sensors extract useful information from the environment and either respond to queries made by users or take the active role of disseminating the information to one or more sinks. The information is then exploited by subscribers/users for environment monitoring, target tracking, and/or decision making. In some sense, a sensor network can be envisioned as a distributed database that provides a layer of query processing for users. How information can be effectively gathered, aggregated, and disseminated to users and how queries made by users can be effectively directed to sensors that have the corresponding information is the focus of this chapter. Specifically, this chapter gives an overview of research activities on data gathering and fusion along three research thrusts: (1) query processing in sensor database systems, (2) data gathering and dissemination mechanisms, and (3) data fusion mechanisms. In each of the research thrusts, this chapter first presents an overview of the various mechanisms and discusses their design objectives and criteria. This is then followed by a taxonomy of existing mechanisms based on their design objectives and criteria. Several utility-based data gathering algorithms that maximize the amount of information extracted, subject to constraints on flow conservation, energy, latency, and/or channel bandwidth, are also presented.