For an infinitesimally small dipole in free space, the electric field Eθ in the far-field is proportional to (e-jkr/r)sin θ, where k = 2π/λ. A vertical infinitesimally small electric dipole (δl ≪ λ) is placed at a distance h (h > 0) above an infinite ideal conducting plane, as shown in the figure. The minimum value of h, for which one of the maxima in the far-field radiation pattern occurs at θ = 60°, is

For an infinitesimally small dipole in free space, the electric field

1.	For an infinitesimally small dipole in free space, the electric field Eθ in the far-field is proportional to (e-jkr/r)sin θ, where k = 2π/λ. A vertical infinitesimally small electric dipole (δl ≪ λ) is placed at a distance h (h > 0) above an infinite ideal conducting plane, as shown in the figure. The minimum value of h, for which one of the maxima in the far-field radiation pattern occurs at θ = 60°, is
A.	λ
B.	0.5λ
C.	0.25λ
D.	0.75λ
Answer» B. 0.5λ

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