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.
接收器和放大器接收来自副反射器的无线电波，并使这些微弱的无线电波强大到足以被记录下来并转化成电子信号。
A receiver and amplifier receive the radio waves from the sub reflector, and make these weak radio waves strong enough to be recorded and turned into electronic signals.
它可以通过由人们呼吸和心跳所引发的，反射无线电波产生的扭曲，来探测障碍的另一边是否有人存在。
It can detect the presence of people on the other side of a barrier by distortions to the reflected radio waves caused by their breathing or heartbeat.
无线电波的波长较长，因此只有大物件可以反射它们。
These have long wavelengths and therefore bounce only off large things.
不同之处是雷达发出的是无线电波，这种波波长较长，反射体只能是大个物体。
The difference is that radar depends on radio waves. These have long wavelengths and therefore bounce only off large things.
通常雷达通过从物体反射回的无线电波来确认位置。
Radar works by recording radio waves that have been reflected from the object under observation.
该扫描仪采用了超冷却磁体和反射无线电波，检测有多少氧合血流分布到受检人员的大脑部分。
The scanner used a super-cooled magnet and reflections of radio waves to determine how much oxygenated blood was in a given part of the subject's brain.
流星余迹通信利用流星电离余迹对无线电波的反射和散射作用来进行通信，它是一种突发通信方式。
Meteor trail communication is a kind of burst communication mode, which USES reflection and dispersion of radio wave to the meteor ionization trails.
尽管象树木、小型建筑之类的小障碍物算不了什么问题，但是如是大障碍物，比如地球，就会反射这些无线电波。
Small obstacles like trees or small buildings aren't a problem; but a big obstacle, such as the Earth, will reflect these radio waves.
结合理论分析，指出无线电波在井巷中引起电波衰减的主要原因是波的折射与反射，而不是巷壁的吸收。
In combination with the result, the author points out that radio wave attenuations in roadway is mainly by wave refraction and reflection rather than wall absorption.
这种反射层和海洋一起，能把无线电波从大西洋的此岸送到彼岸。
Such a reflecting layer, together with the sea, could channel radio waves from one side of the Atlantic ocean to other.
因而意外发现了无线电波可以通过大气反射。
Then it was accidentally discovered that these waves bounce off the atmosphere.
因而意外发现了无线电波可以通过大气反射。
Then it was accidentally discovered that these waves bounce off the atmosphere.
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