Increasing the accuracy of distance measurement between access point and smartphone

This research focused on distance measurement using Received Signal Strength Indicator (RSSl) that utilizing Pythagoras theory to get the position of a smartphone with the help of 4 Access Point (AP) in indoor environment. There were many research have been done in this area, but the issue is about the accuracy. From studies that have been done before, there are differences between the results of calculation using RSSl with the actual distance with the average of 1.6 meters. Our result indicate that when calculating the distance using optimization RSSl method, we can reduce the distance difference average value between Access Point (AP) and smartphone is 0.6 meters with an accuracy of 86.1%. Coordinate measurement using Pythagoras Theory also produce average of localization error valued of 0.6 meters.