Q. A rectangular horn antenna has an aperture area of 3λ × 2λ. If the aperture efficiency of an antenna is 90%, then the directivity of the antenna is:
β
Correct Answer: (B)
17.1 db
Explanation: given the aperture dimensions of an antenna, the directivity that can be achieved is ap4π a/λ2, where a is the aperture area and λ is the operating