This paper describes a method of measuring two-dimensional position of an IC tag. This is simple technique that turns an antenna with directivity and calculates a direction and a distance from a reaction range of a radio wave sent by an IC tag. It is easy to introduce this system in our house in order not to need to install and adjust beacons on a wall. This is available for a lost article search, goal of a mobile robot, making an environment map and so on.
