Frequency offset estimation for galileo/GPS receivers based on differential correlation

Urban and moderate indoor applications of Galileo/GPS receivers require particularly high reception sensitivity. Residual frequency deviations due to unknown Doppler frequency shifts degrade the reception sensitivity. Estimation of the frequency offset can therefore substantially enhance the reception sensitivity of Galileo/GPS receivers. This paper presents a frequency estimation method that is especially tailored for Galileo/GPS receivers using differential correlation. It is suitable for the very low signal to noise ratios of attenuated Galileo/GPS signals and introduces very little additional implementation complexity. The performance analysis presented in this paper shows promising results for an application in next generation Galileo/GPS receivers