On the use of ray tracing for performance prediction of UWB indoor localization systems

The most important factors impairing the performance of radio-based indoor localization systems are propagation effects like strong reflections or diffuse scattering. To the full extent, these effects can be captured only by time-consuming measurement campaigns. Ray tracing (RT) offers the possibility to predict the radio channel for a certain environment, avoiding the need for measurements. However, it is crucial to include all relevant propagation mechanisms in the RT as well as to validate the obtained results. In this paper, we show that sub-band divided RT can yield realistic ultra-wideband channel impulse responses that can be used instead of real measurements. We show this by using the RT results for performance prediction of multipathassisted localization, which depends to a great extent on the above mentioned propagation effects. A previously introduced method to estimate the ratio of the signal energies of deterministically reflected paths to diffuse scattered components is employed on both the RT results and the channel measurements in an indoor environment. This analysis is useful in two ways: first, as this ratio scales the amount of position-related information of deterministic multipath components, it can be used for localization performance prediction; second, this ratio includes two main propagation mechanisms and is thus useful to validate the subband divided RT

On the Use of Ray Tracing for Performance Prediction of UWB Indoor Localization Systems

Abstract—The most important factors impairing the performance of radio-based indoor localization systems are propagation effects like strong reflections or diffuse scattering. To the full extent, these effects can be captured only by time-consuming measurement campaigns. Ray tracing (RT) offers the possibility to predict the radio channel for a certain environment, avoiding the need for measurements. However, it is crucial to include all relevant propagation mechanisms in the RT as well as to validate the obtained results. In this paper, we show that sub-band divided RT can yield realistic ultra-wideband channel impulse responses that can be used instead of real measurements. We show this by using the RT results for performance prediction of multipathassisted localization, which depends to a great extent on the above mentioned propagation effects. A previously introduced method to estimate the ratio of the signal energies of deterministically reflected paths to diffuse scattered components is employed on both the RT results and the channel measurements in an indoor environment. This analysis is useful in two ways: first, as this ratio scales the amount of position-related information of deterministic multipath components, it can be used for localization performance prediction; second, this ratio includes two main propagation mechanisms and is thus useful to validate the subband divided RT. I