Check out the ICRA paper: https://homes.cs.washington.edu/~gshyam/Papers/wirelessfly.pdf

Check out the paper:   https://homes.cs.washington.edu/~gshyam/Papers/videobackscatter.pdf Check out the article by Techcrunch: https://techcrunch.com/2018/04/19/technique-to-beam-hd-video-with-99-percent-less-power-could-sharpen-the-eyes-of-smart-homes/