GPS C/A signal tracking algorithms have been developed based on adaptive Kalman filtering theory. In the research, an
adaptive Kalman filter is used to substitute for standard tracking loop filters. The goal is to improve estimation accuracy
and tracking stabilization in high noise and high dynamic environments. The linear dynamics model and the measurements
model are designed to estimate code phase, carrier phase, Doppler shift, and rate of change of Doppler shift. Two
adaptive algorithms are applied to improve robustness and adaptive faculty of the tracking, one is Sage adaptive filtering
approach and the other is strong tracking method. Both the new algorithms and the conventional tracking loop have been
tested by using simulation data. In the simulation experiment, the highest jerk of the receiver is set to 10G m/s3 with the
lowest C/No 30dBHz. The results indicate that the Kalman filtering algorithms are more robust than the standard tracking
loop, and performance of tracking loop using the algorithms is satisfactory in such extremely adverse circumstances.
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