C-band dishes

[gtsg1098]

Why were C-band dishes so huge?! I'd love to know the answer to this one. Thanks in advance!

 

[Titanium]

C-band frequencies are downlinked between 3.4-4.2GHz. KU-band frequencies are downlinked between 10.7-12.75GHz. The higher the frequency, the shorter the wavelength. To reflect the same amount of signal on a longer wavelength the reflector size must be larger. To reflect the same amount of signal on a shorter wavelength (higher frequency), the reflector is smaller.