Performance Analysis of GPS and Galileo Receivers in Urban Automatic Vehicle Location

Bus priority remains one of the principal strategies adopted in many cities to improve levels of service. Automatic Vehicle Location (AVL) is the key technology of this system. For deep urban location, how to get high sensitivity is the subject problem. The Galileo L1F signal presents many structural innovations in its design. In order to quantify how these changes will affect the High-Sensitivity receiver, we analysis the relationship between frequency offset degradation and the coherent integration time, and this is the key problem for urban navigation receiver. The criterion to choose the optimum integration time length is proposed. We present the architecture of dual model receiver, and the FFT method to process the acquisition more quickly. Theoretical and simulation results clarify that these method is feasible。 Index Terms—GPS, Frequency offset, Galileo, High sensitivity, FFT.