A Battery-Free Cell Phone
Most of us in tech have at one point or another has had thoughts about a battery-free cell phone.
For that matter, most of the consumers have, as well.
After all, most of us nowadays own a battery pack, which proves how hungry our devices are for power.
But put the gadgets aside, and you can, in fact, make a device that requires no battery.
What the device makes use of is radio waves, which we already use for communication.
Still developing it, the researchers were able to make a call between the device and an Android phone.
The technology, however, is not completely new.
It is a simplified version they call passive wi-fi, used previously to power gadgets requiring a tiny amount of electricity.
One such example where it is used is singing posters.
The team, however, faced certain issues – when converting analog human speech to a digital signal, a lot of power is consumed.
In order to be more power efficient, the team had to reinvent a technology last used back in the days of the Cold War – analog backscatter tech implemented in spy kits.
Besides the analog voice transmission, the battery-free device sends number inputs as digital signals.
The signal is transferred to a base station which uses Skype to connect to the digital cellular network.
This base station doesn’t only progress the signal, but it also provides power to the device.
Currently, the station supports a maximum range of about 15 meters.
However, real cell towers have hundred times more power which could increase the range of the battery-free cell phone up to a kilometer.
Although the technology is under development, and the researchers are looking into implementing additional features, it is a sure step towards a more sustainable future.