Locating an Object inside a Room under Line-of-Sight Conditions between Transmitter and Receiver

Abstract

Using the trilateration mechanism for local positioning requires a careful study of the mobile object's coordinates calculation methods, based on the measurement of various physical parameters (signal strength level at the receiver, signal propagation delay, reception angle, etc.). This article will be about choosing the radio propagation model in a case where the transmitter and receiver antennas are located in line of sight of each other inside the room. Increasing the accuracy of determining the subscriber device's coordinates up to 3–5 meters, which is the main goal of this work, is achieved through analytical modeling and field tests of the positioning system in the sampling points of the room. Approximation of the difference between the measured and calculated signal attenuation values by the linear regression allows finding the coefficients of additional losses in the premises manifesting because of multiple signal's reflections from obstacles and other factors. The results of processing experimental data obtained by measuring the signal strength at the sampling points are derived. These data are compared with the results of calculations and used as the basis for determining the target object's location.