Antenna Problems

The Directivity of Isotropic antenna is ......................

• 0

• 100

• 1

• 1000

The length of half wave dipole is .............

• λ/2

• λ/4

• λ/25

• λ

What is the maximum effective aperture of a microwave antenna with a directivity 900?

• 71.6λ²

• 716λ²

• 0.716λ²

• λ²

Calculate the effective height of a λ/2 antenna. Given radiation resistance is 73 Ω, maximum aperture is 0.13 λ^2. And efficiency is 120π.

• 0.3317 λ²

• 0.317 λ²

• 3178 λ²

• 1173 λ²

The Radiation Resistance of a half wave dipole antenna is.........

• 71 Ω

• 73 Ω

• 78 Ω

• 738 Ω