‘Passive Wi-Fi’ uses 10,000 times less power than normal to save your battery

sonnyyu:
‘Passive Wi-Fi’ uses 10,000 times less power than normal to save your phone battery

Hi sonnyyu, thanks for sharing.

Do you know how to duplicate it?

I think this passive Wifi is useful for IOT application. Can we forget Zigbee from now on?

Is this technology able to combine with 802.11AH to make the lowest power design?

tim9510019:
Do you know how to duplicate it?

Just build compatible hardware.

If you read the University of Washington article linked at the end of the article sonnyyu links, it describes sensors that use special WiFi hardware that lacks the analog RF oscillators, instead using the RF energy field from a plug-in device that is within 100 feet (30 meters.) You can't get something for nothing: the power to transmit a signal has to come from somewhere. It appears to me that the potential advantage here is if you have a cluster of sensors/devices in a relatively close area (in the same reasonably sized house?) you can use a single central wired power source while the array of sensors run off of batteries.

The headline of the article in sonnyyu's link mentions how this can save cell phone power - I think the author of that headline didn't think through the technologies limitations (the author appears to be a journalist, not an engineer.) I don't see that as being a practical phone energy savings technology unless you can install one of these plug in devices every hundred feet in the locations you frequent. It seems like it would work for stationary IoT devices, but it sounds like it has very limited usefulness for truly mobile devices.

This could revolutionize fixed location IoT devices. But I don't see it being universally applicable, at least not until more advances are made, or until there is a huge investment in infrastructure. And I don't see it ever happening with the Yun's (or any other system's) existing hardware, as it clearly requires a radio with a special RF front end.