Low-Computation GNSS Signal Acquisition Method Based on a Complex Signal Phase in the Presence of Sign Transitions

During signal acquisition in a global navigation satellite system acquisition stage, a method of signal parameters estimation with low computational complexity is needed. However, due to the influence of sign transitions, the correct peak corresponding to the signal parameters is difficult to detect. For the estimation of the code phase of the received signal in the presence of sign transitions with low computational complexity, an acquisition method based on a complex signal phase (AMCSP) is proposed. The problem of estimating the sign transition position and the code phase is transformed into a problem of solving for a complex signal phase. Special block matrixes are constructed to obtain the complex signal phase, and integration processing is utilized to improve the detection probability performance. Based on an analysis of undesirable cases, a final code phase estimation process is proposed. Furthermore, expressions for the detection performance and computational complexity of AMCSP are derived. Simulation results demonstrate that the computational cost of AMCSP is much lower than that of a fast Fourier transform-based method.