I see you have a few threads going and I want to think this came up recently here or in another forum. You may want to do some research on the term "rectenna" or "rectifying antenna". The idea being tiny diode arrays are built directly into the antenna. Doing this helps eliminate loss. I can't recall who it was but a major US company did some experiments using highly directional microwave transmissions at very high power to a rectenna receiving dish about I think a mile away. The concept was being tossed around for use in space. The merit to microwave transmission is the beam can be made highly directional.
As you see in your other thread low frequency stuff exist for cell phone charging and hell even my electric toothbrush circuits. A Google of "rectenna video" will get you some interesting stuff but the video I recall was out in I believe the southwestern US desert. I just can't remember who it was.
Ron