Indoor positioning and navigation for specific buildings, e. g. in the public sector, is a current requirement for many building operators. Since satellite-based technology, which has been researched, tested and used practically outdoors for many years, is not available inside buildings, other technological approaches have been analyzed and prototyped for several years. The most widely used approach is the use of Bluetooth beacons. This paper shows weaknesses of this methodology based on a metrological investigation and proposes an alternative approach using Pedestrian Dead Reckoning, supported by Bluetooth Beacons and the navigation model used. The results are shown in a prototypical indoor navigation system. Furthermore, an outlook is given on how method and technology can be further improved.