Robust GPS Satellite Signal Acquisition Using Lifting Wavelet Transform

Description

Abstract. A novel GPS satellite signal acquisition schemethat utilizes lifting wavelet to improve acquisition performanceis proposed. Acquisition in GPS system is used tocalculate the code phase (or shift) and find the pseudorange,which is used to calculate the position. The performanceof a GPS receiver is assessed by its ability to preciselymeasure the pseudo-range, which depends on noiselinked to the signals in the receiver’s tracking loops. Thelevel of GPS receiving equipment system noise determinesin part how precisely pseudo-range can be measured.Our objective, in this paper, is to achieve robust real-timepositioning with maximum of accuracy in the presence ofnoise. Robust positioning describes a positioning system'sability to maintain position data continuity and accuracythrough most or all anticipated operational conditions. Inorder to carry out a robust less complex GPS signals acquisitionsystem and to facilitate its implementation, a substitutealgorithm for calculating the convolution by usinglifting wavelet decomposition is proposed.Simulation is used for verifying the performance whichshows that the proposed scheme based lifting wavelettransform outperforms both FFT search and signal decimationschemes in the presence of a hostile environment.