Question

The frequency suitable beyond the horizon communication using sky wave is:

• A. \( 10 \, \text{KHz} \)
• B. \( 10 \, \text{MHz} \)
• C. \( 1 \, \text{GHz} \)
• D. \( 1000 \, \text{GHz} \)

Hint:

Sky wave communication works well for frequencies in the HF band (3–30 MHz); 10 MHz is optimal for ionospheric reflection.

Answer 1

The Correct Option is B

Sky wave propagation (also called ionospheric propagation) is used for long-distance radio communication by reflecting signals off the ionosphere.
- The ionosphere reflects frequencies typically in the range of: \[ \text{2 MHz to 30 MHz} \] - Frequencies below 30 MHz are reflected, but above that, signals penetrate the ionosphere.
Hence, \(10 \, \text{MHz}\) is suitable.