A study of enhancement of ranging performance of beacons through improvement of the smart phone's gyroscope: focusing on the Bluetooth low energy

Currently, in the ROK, IoT holds the limelight and various types of IoT equipments that integrate the "Smart function" to existing electric or electronic equipments are being developed and introduced to the market. It takes many hours and much efforts to attach the smart equipments to each existing equipment to realize a complete IoT system so that this study is to make the central control device to recognize each product, provide relevant information to the product and command it to perform the movements corresponding the command, without additional smart equipments. Since interior structural changes of a household or a building are rare, relevant information can be provided to the user by tracking which object or structure he/she is being positioned in front of. However, the existing commercial positioning systems such as GPS and others often do not offer high-precision level and cannot be used indoors. The proposed system in this article attempts to localize the user's position by triangulation based on the signals emitted from widely installed beacons acting as the reference points. This concept does not use GPS satellite(s) but employ its basic principle. The system adopts the BLE and its exclusive equipments which allow a long-term operation of a beacon from approx. 1.8 to 28.7 months with the CR2045 battery due to their low power consumption rates. Thus, a location-based application service based on the BLE-utilized positioning system has been proposed in this study. In the design, smart phone's geomagnetic sensor and the acceleration sensor have been integrated within the BLE-based ranging system. The distance and direction of a beacon from one's own position will be indicated on the GUI map based on the measurements. In addition, a database for the initial values will be established so that there's no need to set up the initial value beforehand. The position of the relevant object can be estimated by aggregating the realtime measurements in the way of PIC control. This way, a rough estimation can be performed even with just one beacon.