sky wave

基本解释

The transmission of the sky wave is realized by the reflection from ionosphere, especially after reflecting many times, to achieve global communication.
天波的传播是利用电离层的反射来实现的，尤其是多次反射后可以实现全球通信。
The sky wave over the horizon radar (OTHR) is a new mechanism in which the ionosphere is used as a mirror to reflect the radar high frequency signal to detect the target.
高频天波超视距雷达所独有距离多跳现象，使得位于雷达威力覆盖范围以远的杂波通过地面与电离层的多次反射进入到雷达的接收阵列。
Since the surveillance area of sky wave Over-The-Horizon Radar (OTHR) is very vast, realizing the ship detection with short coherent integration time (CIT) is an operational requirement for OTHR.
天波超视距雷达（OTHR）的观测范围非常广，实战中经常要求在短相干积累条件下检测出舰船目标。

China has built several sky-wave based Over-the-Horizon radar stations that for the first time allow the PLA to monitor continuously U.S. Navy ship movements hundred miles out in the Western Pacific.
CENTERFORSECURITYPOLICY: China's one world?

a radio wave reflected back to the earth by the ionosphere (ionospheric wave), permitting transmission around the curved surface of the earth &rarrcompare ground wave