Q. Aconical horn has a side viewas shown in Figure  The maximum value ofthe directive gain is given by GD ∼ = 5.13(D/λ)², where D =√3.33λL1 and L1 = L/(1-d/D),in which d is the inside diameter of the waveguide. Beam widths for the main beam directed along the z-axis are given by θB = 60λ/D in degrees in the yz-plane, and by φB ∼ = 70λ/D in degrees in the xz- plane. Let the circular waveguide, with a 2.5-cm inside diameter, be expanded by adding a conical ?are to have an aperture with an inside diameter of 5.771λ at 8 GHz. For L1 = 10λ, find:

(a) The horn length L.

(b) The directive gain.

(c) The principal-plane beamwidths.