针对远方列车信号很小，且具有很强的噪声，直接通过时域分析误差较大，因此，采取频域分析方法，获取列车接近时的警报信号的规律，以用于便携式列车接近安全报警系统中。

So by means of the frequency-domain analysis, the character of alarming signal can be deduced and used in the system of portable safety alarming system of train approaching.

youdao

针对远方列车信号很小，且具有很强的噪声，直接通过时域分析误差较大，因此，采取频域分析方法，获取列车接近时的警报信号的规律，以用于便携式列车接近安全报警系统中。

So by means of the frequency-domain analysis, the character of alarming signal can be deduced and used in the system of portable safety alarming system of train approaching.

youdao