Localization and tracking using an heterogeneous sensor network

Abstract: Taking resource limitations into account in the design of wireless sensor networks are important in many emerging applications. The need for minimizing the communication and power consumption of individual nodes and other units pose interesting challenges for estimation and control strategies.This document describes the design, implementation, obtained results and conclusions of a cooperative localization and tracking system based on two types of sensors. Practical investigations are made to reach the optimal sensor scheduling based on offline and covariance-based scheduler approaches. One sensor gives low quality measurements and is based on an ultrasound sensor and the other is a web-camera with high precision but with delayed results. The ultrasound sensor is connected to wireless sensor nodes which are part of the KTH Wireless Sensor Network Testbed and the web-camera is connected to a data processing unit and placed in the same area. An overview about localization techniques and solutions are presented. The design, development, and implementation of the KTH Wireless Sensor Network Testbed is also discussed. The software implemented on the system is fully detailed as well as the necessary hardware. A presentation of the filtering methods used to perform localization and tracking is put forward. Analysis and conclusions of all the different approaches used are discussed. Guidelines for future work are also proposed.