AM amplifier having noise figure of 20 dB and available power gain of 15 dB is followed by a mixer circuit having noise figure of 9 dB. The overall noise figure as referred to input in dB is

Electronics and Communication Engineering (ECE) : Communication Systems - Quiz(MCQ)

0.63

10.44

11.07

21.52

Correct Answer : Option (B) : 10.44

Explanation :

Recently Updated in Communication Systems Questions

In TV scanning sequence of lines is

right to left

left to right

left to right for odd fields and right to left for even field

left to right for even fields and right to left for odd field

Correct Answer : left to right

Which of the following terms are applicable to troposcatter propagation?

SIOs

Fading

Faradays rotation

Atmospheric storms

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.

A + 1.9 lens has a focal length of 25 mm. The diameter of lens is about

1.3 mm

130 mm

13 mm

None of the above

Correct Answer : 13 mm