由于电离层会把这些频率的无线电波反射回地球表面，所以数百上千公里以外的接收器可以检测到它们。
Because radio waves of these frequencies are reflected back to the Earth's surface by the ionosphere, they can be detected by receivers hundreds of miles away.
大多数天线被制成碟形，用以收集和反射无线电波至亚反射器，就像曲面镜将可见光聚焦于一点一样。
Most antennas are made in the shape of a dish to collect and reflect the radio waves to the sub reflector, in the same way as a curved mirror focuses visible light to one point.
他们发射那些可以反射雨滴、飞机、蝙蝠以及其他东西的无线电波。
They send out radio waves that reflect off raindrops, airplanes, bats, and so forth.
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