Differential Correction Method of Long-Wave Propagation Time Delay Applied to Complex Long-Distance Path

The precision of the long-wave propagation time delay is the key factor affecting the accuracy of land-based long-wave navigation timing systems. For the complex long-distance propagation path, a differential correction method of long-wave propagation time delay, which combines the integral equation method with the functional relationship model, was presented. The theoretical value of the propagation time delay was calculated by the integral equation method, and the functional relationship model was used to describe the variation of propagation time delay with distance. In the local area, the propagation time delay of the user is corrected by establishing a differential station to monitor the propagation time delay in real-time and determine the model parameters. Experimental results show that the method has significantly improved the accuracy of propagation time delay prediction. The mean absolute error decreased from 0.8585 to 0.2783 \mu {\rm s}, and the root mean square error decreased from 0.8610 to 0.2861 \mu {\rm s}.