Stochastic Modeling in GPS Estimation
The NAVSTAR Global Positioning System (GPS) is a space based satellite radio navigation system which provides three dimensional user positioning by solving a set of nonlinear trilateration equations using pseudorange measurements. The current method of solving the nonlinear equations is to linearize the pseudorange equations and calculate the user position iteratively, starting with a user provided initial position guess . For near earth navigation, the center of the earth is a good initial guess and the currently used Iterative Least Squares (ILS) algorithm is guaranteed to converge towards the GPS solution. An area of potential improvement that has been investigated in recent years is the use of non-iterative closed-form solutions to the nonlinear GPS pseudorange equations. Closed-form solutions have been developed by Bancroft , Krause , Abel and Chaffee , and Hoshen .
KeywordsGlobal Position System Global Position System Receiver Clock Bias Pseudorange Measurement Global Position System Time
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