Patent ID: 9749788
Date: 2017-08-29
CPC Classifications: G01S,H04W

Claim:
1. A method for determining a step length of an entity associated to a radio frequency (RF) node, comprising: receiving a signal propagation parameter of the RF node measured at a first time point; determine a set of first position points based on the signal propagation parameter of the RF node measured at the first time point; assigning a set of candidate moving step lengths to the first position points; receiving a signal propagation parameter of the radio frequency (RF) node measured at a second time point; determining a number of steps made by the entity from the first time point to the second time point; obtaining a set of second position points based on the first position points, the number of steps and the set of candidate moving step lengths assigned to the first position points; and analyzing the second position points based on the signal propagation parameter of the RF node received at the second time point to determine a step length of the entity; wherein the analyzing the second position points based on the signal propagation parameter of the RF node received at the second time includes: for a second position point, determining a proximate fingerprint of the signal propagation parameter, which is pre-sampled at a sampling point geographically proximate to the second position point; ranking the second position point based at least in part on a comparison of the signal propagation parameter of the RF node received at the second time point and the determined proximate fingerprint of the signal propagation parameter; and updating the set of candidate moving step lengths based on the ranking.