The performance of GPS receiver is affected by carrier tracking loop.Because of the vulnerability of carrier tracking in high dynamic and weak signal environments
a method of strapdown inertial navigation system (SINS) aiding GPS tracking loop utilized differential control cogitation is proposed.Phase locked loop (PLL) utilized in traditional carrier tracking is analyzed
and the control mode could be considered as PI (proportion and integration) control.Then the stable of tracking loop with information aiding is verified
and differential control item is introduced to achieve carrier tracking
where the Doppler prediction is calculated by SINS output and clock error.Simulation results indicate that the proposed method could shorten the bandwidth of tracking loop
relieve the contradiction between thermal noise and dynamic stress
and thus further improve the frequency response and tracking errors in carrier tracking loop.