7mo ago

Researchers discover battery-free technology which harvests power from radio and Wi-Fi signals for low-powered devices

www.tomshardware.com Researchers discover battery-free technology which harvests power from radio and Wi-Fi signals for low-powered devices

Applications would result in less dependency on batteries in low-powered devices

cross-posted from: https://lemmy.ml/post/18426215

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schizoidman @lemmy.ml

7mo ago

Researchers discover battery-free technology which harvests power from radio and Wi-Fi signals for low-powered devices

www.tomshardware.com /tech-industry/researchers-discover-battery-free-technology-which-harvests-power-from-radio-and-wi-fi-signals-for-low-powered-devices

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I would find this super cool if it wasnt for the fact that all of the radio frequencies are owned by the military and corporations. Outdoor IoT could be amazing, but it is kind of dead because you cant actually connect it to the internet without laying down cable or using 4G which is horrible for low power applications.
- I don't know what kind of idea you are getting. Radio and wi-ifi are waves. The wave is what can be used, you don't care who generated it. To say it somehow the wave is in the air and you just take advantage of it being there to convert it to energy. Doesn't matter what the wave could have been read as. In general a radio station is not going to stop working for a whole region just to stop you from using it.
  
  Maybe i left out too much context.
  Im not talking about the research itself, but about how it could be utilized.
  Their idea (having small devices that can be powered by nothing but stray radiowaves) apparently works and is great by itself.
  However its usefullness is limited if you cant somehow connect those devices with the rest of the world. Thats the issue im complaining about.
  
  There are tons of small devices that don't have to be connected to be useful. Lots of personal items or small sensors.
  
  Anything that can be powered by this research, can also be powered by a button sized battery for weeks if not not longer. I thinks its more intended for very off grid stuff but maybe im just too uncreative.
  
  I just want it for my TV remote if the form factor is small enough
  
  Good news, that was invented in 1956: https://www.theverge.com/23810061/zenith-space-command-remote-control-button-of-the-month
  
  That's actually really neat!
  
  Huh?
  
  What are you asking for here? Some sort of worldwide free ISP?
  
  There are already lots of concepts for low power wireless communication for example LoRaWAN The issue is not the ISP its the technology used to establish a connection between devices. We need hardware that can run with the low power requirements that come with this research.
  
  That's not any sort of legal issue stopping you, that's physics. If you're trying to create say, some sort of mesh network, and the device is using all of the signal's power just to run itself, there's no power left to retransmit. You don't get something from nothing. We're talking microamps and smaller with these devices.
  If you've ever used a crystal radio, you can get an idea for how weakly powered stuff like this is.
  Edit: look up the channel "EEVBlog" on YouTube, dude has a dozen videos on various such devices and goes into the actual math and viability of each.
- This is the same take as people thinking wind energy steals wind, or solar energy reduces the sun's efficacy.
  
  Wind energy does.
  It's just that we can't extract sufficient energy from it to have any meaningful impact.
  
  Exactly my analogy.
  
  Technically, a properly tuned receiver that's using the signal for power can create radio "shadows" behind the device. People have also been caught with giant coils in their attic siphoning power from nearby radio stations and high voltage power lines, because they can detect the power draw.
  
  They… have? Have a source? That sounds nuts!
  
  You are confusing what i am talking about. See my other response.
- Just use solar and batteries?🤷🏼‍♀️

68 comments