Extra exam question E9D01

WhyAn ideal parabolic reflector antenna's gain increases by about 6 dB when the operating frequency is doubled. An ideal parabolic reflector's gain increases by about 6 dB each time the operating frequency doubles, since the reflector's fixed physical size becomes electrically larger, in wavelengths, as frequency rises, and gain scales with that electrical aperture size, answer D. The smaller 2, 3, and 4 dB figures understate how much gain a fixed-size dish picks up as wavelength shrinks.