The results show that a tunnel radio signal consists of a summation of many propagation modes.
研究结果显示：矩形隧道电磁波的传播，是由多种模式共同作用的结果。
2
It can monitor the crack signal in the concrete structure, for example, bridge, highway, tunnel and building etc., using the embedded optical fiber sensor.
它是用埋入式光纤传感器来监测类似桥梁、高速公路、隧道和房屋建筑等混凝土结构中的开裂信号。
3
The antenna has a simple structure, light weight, easier design, lower cost, fit for the signal cover of the narrow and long region such as tunnel, expressway, long buildings.