On Tuesday June 1rst at 11:40, Dr. Kaoru Sezaki (瀬崎先生) associate professor at The University of Tokyo will give a presentation in Electronic Department Auditorium.

RFID-based positioning systems and urban-sensing systems

Currently, GPS is widely used in systems that provide location-based services to consumers. However, GPS’s inability to operate indoor and urban canyons inhibits us to implement applications anywhere at any time. Further, even though mobile phones with GPS capabilities are becoming widely available, the accuracy is not sufficient to respond to emergency calls and other critical missions. To realize seamless and accurate positioning system that works in a wide variety of environments, we organized a team of experts from the University of Tokyo and four governmental research institutes in the national project called “RFID-based positioning systems for enhancing safety and sense of security” In the positioning systems of our project, users’ devices obtain ID numbers from the embedded RFID tags in physical spaces. The devices then retrieve corresponding location information by querying a database or the cached data when the system is temporally out of connection to the Internet. This RFID-based localization technique use inexpensive RFID tags that can be deployed easily in environments without any network infrastructures. That said, the deployment cost of RFID is not just about the price of tags. It includes the cost of physically embedding the tags, measuring their precise positions, and updating their position data in the database. We proposed various techniques to decrease this “hidden” cost　since the national geographic survey is planning to deploy these RFID tags in entire Japan for location infrastructure.
To reduce the deployment cost of RFID tags, it is also important to relax the density requirement of the reference points. We therefore proposed a localization mechanism that exploits motion sensors and P2P-based technique to enable continuous positioning even when the reference points are sparsely deployed. We assume that pedestrians carry a device that is equipped with an RFID reader, motion sensors such as gyros and accelerometers for dead reckoning, and IEEE 802.11 capability. When the device is in proximity with RFID tag, it directly obtains location information from it. When the device is not in proximity with any RFID tags, it can still estimate its position by dead-reckoning. Further, collocated devices exchange their location estimation and perform sophisticated localization to keep the accuracy even on this condition. On top of this positioning infrastructure, National Research Instiute of Police science, National Research Institute of of Fire and Disaster and NICT are implementing various applications to enhance the sense of security in emergency as well as in daily life such as monitoring and analyzing the daily behavior of children.
I also briefly introduce the on-going real urban sensing project which utilizes wireless sensor networks and mobile phones conducted in Tatebayashi City, which is the hottest city in Japan.