If you have a particle stream, and from the origin of the particle stream you send a electromagnetic signal, does it reaches the target of the particle stream with a drop better than 1/r^2?

Here particle stream can mean subatomic particles, or larger particles such as a sand-like material.

The motivation for this study is a way to transfer energy from orbit, say in orbital solar farms. It would be like a waterfall falling from orbit, that you would replenish from supply trips. The energy math (to send up, to receive) would need to be advantageous.

A variant of this if this idea, with the same purpose, is if sand-like material is actually tiny-bateries, dropped from orbit and collected on the ground. I don't know if there is a size or shape of particles that feels less with reentry.