Antenna Dish Sizes

During the descent phase, a large communications dish will not be required. We can use S-band antennas to transmit a signal through the Lunar Transfer Vehicle or the telerobot on the Lunar Surface, which can act as a relay.

On the LTV, a dish of around two meters will be needed for heavy Ku-band traffic during the translunar and transearth flight phases.

Once the exploration base is on the moon, we can have the crew deploy a nice big dish. This might be as big as 4 meters diameter, or even bigger if we can figure out how to keep the structure light enough.

It can unfold like an umbrella and be made out of a mesh of fine wires -- if the wires are less than 1/2 wavelength apart, the dish reflector will appear optically opaque to the radio waves. That is, a perfect reflector. Light waves get through because they don't interact with the metal.

Another option is to have the structural members inflatable, although there may be an issue with having to replace gasses due to leakage.