The new sheet-like sensor (image courtesy of NEC)
The new sheet-like sensor (image courtesy of NEC)
[Click to enlarge image]

NEC Corp developed a system that accurately detects the shapes and movements of people and objects by using weak radio waves.

It uses a sheet-like sensor and analysis technology that were developed by NEC and detects, for example, the entrance and exit of a person without using a camera. The company expects that the system will promptly detect unexpected incidents without invading privacy in public facilities, etc.

Services of keeping an eye on elderly people and security-related services usually require a camera, raising privacy and cost issues. On the other hand, the new system can be realized by using (1) the sheet-like sensor that uses radio waves and (2) the technology of analyzing data collected by the sensor.

The sheet-like sensor emits weak radio waves from its surface and detects the state of footprints, etc based on unstable radio waves and their intensity difference. The thickness of the sensor is several millimeters, but it is tough enough to be used in a place where many people walk. It can be just placed on a floor or embedded in it.

With the analysis technology, data collected by the sensor can be used to detect the shapes and orientations of soles, the directions in which footprints are moving (being made), etc. As a result, it becomes possible to recognize wheelchairs and guide dogs as well as the movements of people.

Compared with conventional sensors that have an equivalent accuracy, the new sensor system enables to construct a sensing environment with about a 90-98.9% lower cost, NEC said. The company considers that the system can be used for (1) promptly detecting an elderly person or patient fallen on a floor that is unattended in nursing homes, hospitals, etc, (2) detecting the entrance of a person into a restricted area, (3) keeping track of the trespasser's movements and (4) measuring the congestion status of a specific area.