FWIW, Wi-Fi is generally considered a poor source of harvestable RF for little doodads you might want to power passively. Among other issues, there's a lot of "quiet time" as radios on the same Wi-Fi network negotiate who gets to use the channel at a given moment.
If you are interested in the challenges of harvesting energy from Wi-Fi and some ways to address those challenges, here's a nice paper (originally in CoNEXT 2015) from a team I was fortunate to be on: https://cacm.acm.org/magazines/2017/3/213830-powering-the-ne...
[Edit: the relevance here is that, even with an awesome antenna like the one in the news, the Wi-Fi protocol kinda works against you, which raises a bunch of interesting questions.]
If you are interested in the challenges of harvesting energy from Wi-Fi and some ways to address those challenges, here's a nice paper (originally in CoNEXT 2015) from a team I was fortunate to be on: https://cacm.acm.org/magazines/2017/3/213830-powering-the-ne...
[Edit: the relevance here is that, even with an awesome antenna like the one in the news, the Wi-Fi protocol kinda works against you, which raises a bunch of interesting questions.]