Question

What are the length and the flare angle of the H-plane horn antenna with aperture 10 λ and path difference δ=0.2λ?

(a) Length=31.8λ,flare angle=4.15°

(b) Length=62.5λ,flare angle=9.14°

(c) Length=31.8λ,flare angle=9.14°

(d) Length=62.5λ,flare angle=4.15°

I have been asked this question by my school teacher while I was bunking the class.

This intriguing question comes from Design in section Horn Antenna of Antennas

Answer 1

Right answer is (b) Length=62.5λ,flare angle=9.14°

The best I can explain: Length of the H-plane horn \(ρ=\frac{h^2}{8δ}=\frac{(10λ)^2}{8×0.2λ}=62.5λ\)

Flare angle of the H-plane horn \(= 2tan^{-1}⁡\frac{h}{2ρ}=2×tan^{-1}⁡\frac{10λ}{2×62.5λ}=9.14° \)