Patent ID: 11885900
Assignee: TECHNISCHE UNIVERSITÄT MÜNCHEN
Field: Measurement (Instruments)
Classification: CPC G  H | IPC G  H

Claim 0:
1. A computer-implemented method for tracking a mobile device in a geographic area based on a series of motion measurements of said mobile device, said method comprising the steps of:
a) retrieving a topological map for said geographic area, said topological map providing a graph of topological paths through said geographic area, wherein each topological path is associated with a corresponding path direction;
b) statistically generating, on a virtual map of said geographic area, a plurality of particles around an estimated initial position of the mobile device, a spatial dispersion of said particles representing an initial uncertainty of said estimated initial position of the mobile device;
c) determining, from said series of motion measurements, a measured displacement vector of the mobile device, the measured displacement vector representing an estimated displacement direction and an estimated displacement distance of the mobile device;
d) displacing each of said particles on the virtual map according to a randomized particle displacement vector which is derived from said measured displacement vector based on an uncertainty of the measured displacement vector and recording said particle displacement vector for each displaced particle;
e) determining a weight of each particle based on one or more of a comparison of the respective particle displacement vector with the path direction of an adjacent topological path and a distance of the particle to the adjacent topological path;
f) resampling the plurality of particles, said resampling comprising selecting a subset of said displaced particles based on a particle-weight dependent selection criterion, wherein said selection criterion is such that particles with lower weight are more likely to be resampled than particles with higher weight; and
g) wherein the resampling further comprises regenerating said selected subset of displaced particles within a particle regeneration area around a current mean location of the plurality of particles according to a probability distribution.