PROBLEMS 115 2.4. Find the half-power beamwidth (HPBW) and first-null beamwidth (FNBW), in radians and degrees, for the following normalized radiation intensities: (a) U (0) = cos 0 (c) U(0) = cos(20) cos (20) (e) U(0) = cos(30) (b) U(0) = cos² (d) U (0) (d) U(0) = cos² (20) (0 ≤0≤90°, 0 ≤ ≤ 360°) (f) U(0) = cos² (30) (f) U(0)