Indoor Positioning Using Linearly and Circularly Polarized Antennas

Abstract

The article deals with the possibility of combination of linear and circular polarized antennas in case of indoor positioning techniques based on signal strength measurement. We have investigated the distribution of the received power by a quasi-three-dimensional, own developed ray tracing model and by measurement in LoS (Line of Sight) and NLoS (Non Line of Sight) scenarios. The model takes into account the direct propagation path, the first-and second-order reflected waves as well as the effect of diffraction. The utilization of linear and circular polarized antennas instead of only linear polarized antennas decreases the standard deviation of the received power and enhances the effective range. We have performed positioning with the simulated and measured powers using the mean squared error method in case of three transmitters. The average positioning error is significantly reduced by usage of the two various types of polarization antennas compared to the use of merely linearly polarized antennas.