Precise synchronization approach based on multi-rate interpolation and least squares method
基于多速率内插和最小二乘法的精确同步方法

The least squares method utilizing the symmetry of the correlation curve of the PN sequence can achieve accurate measurement of the PN sequence phase. However, in practical applications, the wireless channel bandwidth is limited, so that the restored PN sequence is only consistent with the original wave in the polarity which can led to the deformation of the correlation curve and limiting the actual measurement accuracy of the least squares method. To further improve the measurement accuracy of the least squares method, this paper introduced a multi-rate processing method without increasing the front-end AD sampling frequency by increasing the number of phase detector points near zero, that made the points which were used to fit the straight closer to the zero. The simulation result shows that measuring performance of the twice interpolation method gains about three times improvement compared with the approach without interpolation. So with multi-rate processing, the measurement method of PN phase can significantly improve the performance.