Piecewise Fitting Technology of Group Delay Difference Based on Fourier Decomposition

Pseudo-range measurement based on DSSS system has been widely used in satellite navigation, radar, aerospace measurement and control, deep space exploration and other fields. The group delay and amplitude characteristics of the signal channel of the high-precision navigation receiver are mainly determined by the RF front-end, and the group delay characteristics have a great influence on the high-precision navigation and positioning system. In order to explore the influence of group delay characteristics of RF front-end on pseudo-range measurement, it is necessary to fit the group delay characteristics with high precision. According to the fitting requirements, this paper proposes the piecewise fitting technology of group delay difference based on Fourier decomposition, which has high fitting accuracy, fast calculating speed, and estimation performance of receiver correlation peak distortion, which has a good fitting performance of group delay characteristics.