Loran-C信号中直达波与反射波的提取方法研究
A Study on the Extraction Method of Direct Wave and Reflected Wave in Loran-C Signal

Loran-C信号中直达波和反射波到时差的提取是利用其进行测距的关键所在。通过分析Loran-C信号实测波形与理论波形的特征，认为两者所包含的直达波信号一致。基于此特征，通过波形相减的方法从实测Loran-C信号中剔除理论直达波信号，并结合互相关方法求解出直达波和反射波的到时差。
Determining the difference in arrival time between direct waves and reflected waves in the Loran-C signal is crucial for effectively using it for ranging.Based on the analysis of waveform characteristics of the measured waves and theoretical waves in Loran-C signal, it is considered that the direct wave signal included in the measured Loran-C signal is consistent with that in the theoretical signal.Therefore, the theoretical direct wave signal can be removed from the measured Loran-C signal via waveform subtraction, then the difference in arrival time between direct waves and reflected waves can be calculated by using cross-correlation method.