RF-powered computers are small devices that compute and communicate using only the power that they harvest from RF signals. While existing technologies have harvested power from ambient RF sources (e.g., TV broadcasts), they require a dedicated gateway (like an RFID reader) for Internet connectivity. We present Wi-Fi Backscatter, a novel communication system that bridges RF-powered devices with the Internet. Specifically, we show that it is possible to reuse existing Wi-Fi infrastructure to provide Internet connectivity to RF-powered devices.
From the PDF:
[W]e seek to design RF-powered devices that communicate directly with commodity Wi-Fi devices. A positive answer would pave the way for a rapid and simple deployment of the RF-powered Internet of Things by letting these devices connect to existing mobile phones and Wi-Fi APs. It would also expand the functionality of Wi-Fi networks in a new direction: from providing connectivity to existing Wi-Fi clients to a whole new class of battery-free devices.
Achieving this capability, however, is challenging since conventional low-power Wi-Fi transceivers require much more power than is available from ambient RF signals. Thus, it is not feasible for RF-powered devices to literally speak the Wi-Fi protocol. Conversely, since existing Wi-Fi devices are specifically designed to receive Wi-Fi signals, it is unclear how they would decode other kinds of signals from RF-powered devices.
(Score: 2, Interesting) by Adamsjas on Sunday April 22 2018, @12:48AM (3 children)
Transmit power is not altered by the number of receivers. But I'm betting you know that and were going for funny.
(Score: 2, Informative) by Anonymous Coward on Sunday April 22 2018, @01:12AM (2 children)
Power is expended when an RF leech tethers to a phone and gains connectivity by causing the phone to transmit to a tower. More RF leeches means more power expended.
I'm betting you know that and you're a fucking asshole.
(Score: 1, Interesting) by Anonymous Coward on Sunday April 22 2018, @01:26AM
be nice please! lol
(Score: 2) by Osamabobama on Monday April 23 2018, @10:51PM
The power harvesting comes from relatively high power signals, like television broadcasts. There is no need, nor capability, for these devices to send power level commands to the emitter.
On the other hand, tethering to a phone to cause it to transmit more power is certainly possible, but that's not what we are talking about here. Furthermore, that tether would require some sort of communication protocol, such as Wi-Fi, but that was specifically ruled out as impractically power hungry for Wi-Fi powered devices.
Appended to the end of comments you post. Max: 120 chars.