Design of Smart-Phone Sensor-Based Indoor Location Based Service System

This paper introduces our design of Indoor Location Based Service System. The system is a client-server system. The client is an Android application. The app determines the user's current location with smart phone sensor values. Among the smart phone sensors, it mainly uses accelerometer and compass. It determines the user's moving direction with the orientation sensor whereas it counts steps by investigating accelerometer values. It is known that the average step length is 31 inches while the average stride length is about 62 inches. Therefore, with the number of steps and orientation, the system determines relative coordinates of the user's current location from the user's previous location. Based on the user's current location, the system provides useful information to the user.