frequency modulated track circuit

例句：

1. 1. The new frequency-modulatedtrack is designed to improve the efficiency oftransportation.
   新的频率调制轨道设计用来提高运输效率。
2. 2. The frequency-modulated track circuitwas developed to reduce electromagnetic interference incommunication systems.
   频率调制轨道电路被开发出来，以减少通信系统中的电磁干扰。
3. 3.The frequency-modulated track circuit isused in high-speed railways toensure safe and reliable travel for passengers.
   频率调制轨道电路用于高速铁路，以确保乘客的安全和可靠旅行。