Theremin as a Capacitive Sensing Device

I am really new to both electronics and programming, so please bare with my ignorance.

Just wondering if it is possible to enlarge the effective radius of this project,
perhaps with a larger diameter antenna, around 3meters ?
(although it is suppose to be around 1 meter)

If it is possible, I assume all other components should somehow also be scaled up?

Would that still be supported by the UNO?

that's a lot of questions, perhaps even incorrect assumptions,
hope someone could help me out here

=)