Question

Which of the following frequencies will be suitable for horizontal communication using sky waves?

Answer 1

1. Waves of frequency around 10 kHz cannot be used for horizontal communication because they require a massive antenna for receiving which is not physically possible
2. Waves that have a frequency between 1 GHz and 1000 GHz cannot be used for this purpose as they have high energy causing them to penetrate the atmosphere and not reflect.
3. Hence waves having a frequency 10 MHz are reflected by the ionosphere and thus used for propagation through sky waves.