Patent ID: 8035552

Claim:
A method for mitigating atmospheric errors in code and carrier phase measurements based on signals received from a plurality of satellites in a global navigation satellite system, the method comprising: estimating a residual tropospheric delay, the residual tropospheric delay modeled as a state in a Kalman filter, and wherein a state update function of the Kalman filter for the residual tropospheric delay includes at least one baseline distance dependent factor, wherein the at least one baseline distance dependent factor corresponds to a baseline distance between a reference receiver and a mobile receiver; and updating an estimated position of the mobile receiver in accordance with the estimated residual tropospheric delay and the code and carrier phase measurements, wherein the estimated position of the mobile receiver is modeled as coordinate states in the Kalman filter; wherein the state update function of the Kalman Filter includes a dynamic model Q k for the residual tropospheric delay given by: Q k = σ trop 2 2 ⁢ β trop ⁢ ( 1 - ⅇ - 2 ⁢ β trop ⁡ ( t k - t k - 1 ) ) ⁢ ⁢ and σ trop 2 = σ hor 2 × l 2 + σ v 2 × Δ ⁢ ⁢ H 2 where 1/β trop comprises a correlation time of a troposphere wet component of the residual tropospheric delay, σ trop 2 comprises a troposphere wet variance component of the residual tropospheric delay and is a function of the baseline distance l and height difference ΔH between the reference receiver and mobile receiver, σ hor 2 comprises a variance for a horizontal wet component of the residual tropospheric delay, and σ v 2 comprises a variance for a vertical wet component of the residual tropospheric delay.