Design of GPS Receiver Embedded Positioning and Navigation Algorithm Solution

This paper focuses on the embedded algorithm design of GNSS Receiver's solution for Positioning, Velocity and Time (PVT). Based on the principle and characteristics of the receiver's baseband, the strategies of preprocessing and noise setting of the measurements Output to PVT. according to the power of each channel's tracking signal and the DLL/FLL/PLL correlation status, are described with some formula illustration. Sequential Least Square (LSQ) and Expanded Kalman Filter (EKF) are also introduced into the PVT Solution with some improvement aided by the possible priori-information from the receiver's altitude, position and TCXO's frequency variation in the first positioning while power on the receiver and in the continuous working environment. Robust estimation by outlier detection and down-weighting in LSQ and EKF, adaptive dynamic noise adjusting, in EKF according to the monitored acceleration variation of the vehicles are also used in this solution. To avoid the huge computation burden in the embedded ARM CPU, the sequential EKF is adopted too. Finally, the flow chart of the whole PVT design is provided.