Patent ID: 9743233
Date: 2017-08-22
CPC Classifications: H04W

Claim:
1. A device, comprising: a first positioning circuit that is configured to determine a position of the device before the device becomes inactive; a second positioning circuit that is configured to determine an estimated distance that the device travels relative to the position; and a control circuit that is configured to i) obtain a current wireless fingerprint of the device when the estimated distance exceeds a first predetermined threshold and ii) reactivate the first positioning circuit when a difference between the current wireless fingerprint and a previous wireless fingerprint of the device exceeds a second predetermined threshold, wherein the difference between the current wireless fingerprint and the previous wireless fingerprint is measurable based on i) a number of repeated wireless station ID(s) that are present in the current wireless fingerprint and the previous wireless fingerprint, or ii) received signal intensities in the current wireless fingerprint and the previous wireless fingerprint that are associated with the repeated wireless station ID(s).