A high-frequency carrier is needed mainly because:

Low-frequency signals cannot be radiated efficiently from a practical aerial

FM is more resistant to noise than AM because:

The information is in the frequency, so amplitude noise can be removed

Twice the highest modulating frequency

Modal dispersion from many light paths

Higher bandwidth and immunity to electromagnetic interference

12questions. Pick an answer and you'll see why right away.

A communication system consists of a transmitter, a channel and a:
A high-frequency carrier is needed mainly because:
In amplitude modulation, the property of the carrier that is varied is its:
In frequency modulation, the property of the carrier that is varied is its:
FM is more resistant to noise than AM because:
The bandwidth of an AM transmission is:
Attenuation of a signal in a channel means the signal:
Light is guided along an optical fibre by:
For total internal reflection in a fibre, the core must have a refractive index that is:
Multimode fibre limits the data rate over distance because of:
For a long-distance, high-data-rate link, the preferred fibre is:
Which is an advantage of optical fibre over copper cable?