Investigation and Demonstration of Local Positioning System Using Ultrasonic Sensors for Wide Indoor Areas

This paper proposes an indoor positioning system for detecting the location of a moving object such as a person or a goods trolley in a wide indoor area. Conventional system requires synchronization between transmission and receiving unit. As a result, they include not only an ultrasonic part but also a radio part to maintain synchronization. We have developed a system that uses only ultrasonic waves, that is, an asynchronous system. The system configuration and sequence of operation are explained and the verification system which includes H8, PIC microprocessors and a PC for positioning calculation is described. It was confirmed that the proposed method is valid and the positioning error is within 100mm.