Question

Find the HPBW of the uniform rectangular aperture antenna with 4λ×2λ in the E-plane?

(a) 0.443

(b) 0.886

(c) 0.25

(d) 0.5

This question was posed to me in an internship interview.

My question is from Aperture Antenna topic in portion Aperture Antenna of Antennas

Answer 1

Correct choice is (a) 0.443

The best I can explain: HPBW = 2 arcsin⁡\((\frac{0.443\lambda}{b})\)≈0.886λ/b=0.886/2=0.443.