Scalar and vector tracking loop simulation based on a uniform semi-analytic model and robustness analysis in multipath/NLOS situations

A semi-analytic model is proposed to efficiently analyze and compare the performance of both the scalar tracking loop (STL) and the vector tracking loop (VTL) in different operating situations. The quality of each satellite signal, including multipath and none-line-of-sight (NLOS) propagation problems, can be incorporated into the proposed model for different configurations of deteriorated situations. Theoretical analysis of multipath and NLOS induced bias to the VTL and STL is given, including the bias envelop, from which a conclusion is obtained that the VTL performance is not better than the STL in certain multipath situations. The results from the semi-analytic model verify the theoretical analysis. The effectiveness of the proposed model is verified by a comparison with the results from simulated NLOS data processed by a software-defined radio receiver.