The Anti-jamming Performance Analysis for Vector Tracking Loop

Abstract

Because Global Positioning System (GPS) is easily interferenced by other signal, this paper designs an anti-jamming GPS vector tracking (or vector lock loop-VLL) receiver, which improve its anti-jamming performance on the tracking loop. The traditional scalar tracking loop (or scalar lock loop-SLL) tracks the satellite independently. There is no information exchange between each channel, which ignores the relationship between the receiver’s navigation (position and velocity) and the tracking loop information (code phase and Doppler frequency). The vector tracking loop take the advantage of this relationship, and combine the navigation filter with tracking loop in a Kalman filter, which improve the receiver’s anti-jamming ability and robustness. The simulation analyzes the influence on the tracking loop whether there has an interference, and this paper gives the comparison of position and velocity error. Finally, the weighted least squares method is used to compare the variance of predicted pseudorange error of the two tracking loops when the power of the interference changed. This paper concluded that the vector tracking loop has better anti-jamming ability.