Patent ID: 8125382
Filing Date: 2012-02-28
Classification: G01S

Abstract:
1. A method of predicting a location of a satellite, comprising: receiving, at an RF antenna of a GNSS device, position data and a velocity associated with a satellite, said position data and velocity valid for an effective time period; the GNSS device calculating, at a time during the effective time period, a correction for reducing error between predicted position data and a predicted velocity of the satellite and the position data and the velocity of the satellite, the predicted position data and the predicted velocity being determined using a previously calculated orbit state vector stored in memory of the GNSS device; the GNSS device calculating a current orbit state vector using force model coefficients adjusted based on the correction and storing the current orbit state vector in the memory, the current orbit state vector being used as initial state for propagating an orbit of the satellite within a predicted time period, at least a portion of the predicted time period occurring after the effective time period; and the GNSS device determining the location of said satellite using the orbit.