Development of Positioning System and Fixing of Object Falling Based on Wi-Fi Wireless Network

Abstract

The paper discusses the current issue of using the unregulated capabilities of Wi-Fi networks and creating a software and hardware complex for deploying a local positioning system based on measuring the received signal strength (RSSI). The system can be implemented both in the already existing Wi-Fi infrastructure, and specially designed. To calculate the coordinates, we used the algorithm Weighted centroid (center of mass), which calculates the coordinate of the agent as a linear combination of the coordinates of access points, taking into account the power of the signals, as a characteristic of the weight. The location of an object equipped with a special label is displayed on the user’s personal computer in real time. The data from the tag is transmitted over Wi-Fi. The use of an accelerometer in this system allows for solving the energy saving problem, which is actual for such systems. Another task that helps to solve the accelerometer is to determine the fall of the object, in which case a special signal is sent to the control device. The error in determining the location at three points is 5 meters. As the number of points increases, the positioning accuracy increases. In this case, with the use of 6 points, the error in determining the location decreases to 1.5 meters.