How hot do you expect it to get?
What's the operating frequency?
As an alternative to gold if that's not possible, I might consider using a silver or copper plate and coating it with a low loss tangent material like teflon for acidic protection. You would have to avoid coating the connecting...
Navigational radar uses a highly directional beam that will not affect anyone on deck. Power densities are negligible.
For a comparison point, consider the low-frequency non-directional beacons that the Air Force used to have in the Portuguese Azores. (Current versions are different) Transmit...
