Correct Answer : Option (B) : helical
Explanation : Helical antenna produces a circularly polarized radiation if its two components are at right angles and are equal. It is very commonly used in radio telemetry.
Correct Answer : left to right
Correct Answer : Fading
Explanation : Tropospheric scatter propagation is subject to two types of fading called Rayleigh fading (due to multipath propagation) and fading due to variations in atmospheric conditions along the propagation path.
Correct Answer : 13 mm