Wireless indoor ranging systems

Knowing where one is has always been an important question. With technology we have always been able to solve this question. Especially with the latest advances in GPS solutions, we have always found a location outdoors. But indoors this is a bigger problem, which currently has no ready-made solution. The aim of this research is to develop a practical indoor ranging system and to find its limitations. The specification that was once proposed is: 1 mm accuracy within 1 ms and an average consumption of 1 mW. This specification makes it possible to use drones very accurately indoors. Because of its low power, this future solution can be used to find objects and things. In this research two practical solutions have been made. These two solutions are different in terms of frequency of use and technology used. The first project, OmniTrack, was a complete implementation of an indoor positioning system. This system works to a frequency of 60 GHz, a millimeter wave band. This high frequency allows to use a high bandwidth to achieve the required specifications. The accuracy of the ranging signals was below centimeter level. A two solution is more based on commercially available building blocks. This second system was only aimed at completing ranging measurements, this is the basis of indoor positioning. The accuracy of this system was below 10 cm. The worse accuracy is to dedicate to the lower bandwidth and the influence of multipath propagation. However, in order to know what determines the performance of these systems, we also investigated the influence of the wireless channel and the hardware used. The biggest factor that limits the preformation of an indoor location system is multipath propagation. For this purpose, every model that can be used is made to evaluate a system or a practical setup in a room. From both systems and the channel models it can be concluded that bandwidth is the most important parameter. And on this parameter rests also the biggest limitations, not all frequency may or can be used.status: publishe