Are you looking for an AV sender/receiver?
This is a common function with a lot of commercially available products, especially at the consumer level. Search on that term and see if you can find some that offer what you want.
Most offer transmission by RF, some by cable ... but are you after an optical transmission path by,say, a laser beam? It's a little unclear to me.
If you are after something a bit more special, please let us know some specifics.
Are you after a point-to-point solution, transmit to an existing receiver, etc.
Are you working with analog and/or digital inputs/outputs.
... and so on.