Question

If the aperture antenna is tapered only in H-plane then which of the following is true compared to uniform non-tapered aperture antenna?

(a) Principle patterns in E-plane and H-plane are same in both cases

(b) Principle patterns in E-plane and H-plane are different in both cases

(c) Principle patterns in E-plane is same and H-plane is different

(d) Principle patterns in E-plane is different and H-plane is same

This question was addressed to me in final exam.

My enquiry is from Radiation from Rectangular Aperture in chapter Aperture Antenna of Antennas

Answer 1

The correct option is (c) Principle patterns in E-plane is same and H-plane is different

The explanation is: Tapering is done to reduce the SLL effect. Since the E-plane is not tapered, its principle pattern is same but in H-plane as the aperture is tapered principle pattern will be different from the uniform aperture antenna.