Patent ID: 9739891
Date: 2017-08-22
CPC Classifications: G01S

Claim:
1. A method of determining the location of a mobile device, comprising; estimating a first position, velocity and timing (PVT) data of a mobile device and an associated quality metric from navigation satellite positioning data; receiving a first signal of opportunity (SoOP) at the mobile device, wherein the SoOP is an ambient radio frequency (RF) transmission that is not intended for navigation, position or timing purposes; estimating a second PVT data of the mobile device from the received SoOP; comparing the quality metric to a threshold; if the quality metric is greater than or equal to the threshold, implementing a vector tracking loop using the first PVT data to provide a first satellite tracking parameter data; if the quality metric is less than or equal to the threshold, implementing a vector tracking loop using the second PVT data to provide a second satellite tracking parameter data; tracking a navigation satellite using the first or second satellite tracking parameter data; receiving navigation signals from the tracked navigation satellite; and determining a third estimated PVT data for the mobile device from the received navigation signals.