Indoor location and communication system for the last-ten-meter information services

A novel free space locating and communicating system is described for an implementation of indoor location-based information services at the last-ten-meter area. The communication system, named "i-lidar system", is composed of base stations, i-lidars, and handheld communication terminals, My Buttons. Reflectivity modulating communication technique using a corner reflecting device and a liquid crystal light modulator is used to reduce power consumption of the terminal. Direction (position) and transferred data of the terminal are measured by a high-speed machine vision camera and photodetectors. Steered and modulated eye-safe laser beams are used to feed data to the terminals separately. Validity of the i-lidar system is evaluated by human tracking experiments.