Question

The principle plane pattern of the E-plane of rectangular aperture of a×b is given by F(θ) = ______

(a) \(\frac{sin⁡(0.5kbsin\theta)}{0.5kbsin\theta}\)

(b) \(\frac{cos⁡(0.5kbcos\theta)}{0.5kbsin\theta}\)

(c) \(\frac{sec⁡(0.5kbsin\theta)}{0.5kbsin\theta}\)

(d) \(\frac{1-sin⁡(0.5kbsin\theta)}{0.5kbsin\theta}\)

I had been asked this question in exam.

I need to ask this question from Radiation from Rectangular Aperture in division Aperture Antenna of Antennas

Answer 1

Correct choice is (a) \(\frac{sin⁡(0.5kbsin\theta)}{0.5kbsin\theta}\)

Explanation: The principle plane patterns for the uniform rectangular aperture antenna is given by

F(θ) = \(\frac{sin⁡(0.5kbsin\theta)}{0.5kbsin\theta}\) and main lobe occurs when θ =0.