  Multi-source fusion positioning is one of the technical frameworks for
obtaining sufficient indoor positioning accuracy. In order to evaluate the
effect of multi-source fusion positioning, it is necessary to establish a
fusion error model. In this paper, we first use the least squares method to
fuse the radio fingerprint and the PDR positioning, and then apply the variance
propagation laws to calculate the error distribution of indoor multi-source
localization methods. Based on the fusion error model, we developed an indoor
positioning simulation system. The system can give a better positioning source
layout scheme under a given condition, and can evaluate the signal strength
distribution and the error distribution.
