Mobile phones have become the most inseparable component of humanity in this era where the world stands at the juncture of Fourth Industrial Revolution. With the invention of battery free cellphone, it won’t be inaccurate to say that it’s a giant leap forward. There was a buzz about the need of such marvel in the technology corridors of the globe of late, and the final success has received high commendation worldwide. Now we finally have a functional phone that consumes zero power.
The invention has been pioneered by the researchers of the University of Washington. They have invented a cellphone that can send and receive calls by using just a few micro watts of power. The prototype of this design has been made of certain commercial components. It was demonstrated in a technical paper ‘Proceedings of the Association for Computing Machinery on Interactive, Mobile, Wearable and Ubiquitous Technologies.’ Cellular transmission works on the basic tenet of physics where analog signals have to be converted into digital data that conveys sounds to both ends of the communication device. Interestingly, this basic component has been eliminated as it consumed too much energy. They have instead created a phone that takes advantage of tiny vibrations in a phone’s microphone or speaker. This vibration occurs when a person is talking into a phone or listening to a call. These components have an antenna connected to it, responsible for converting that motion into changes in standard analog radio signal emitted using a cellular base station. This speech pattern encoding process, resulting in radio signals consumes almost no power.
The transmission of speech is executed by the encoding of radio signals into sound vibrations. The prototype was demonstrated using a printed circuit board and off-the-shell components. Their power budget is 2.5 microwatts. A decrease of power about 10,000 times was the biggest challenge. This technology is compatible for integration with standard cellular network infrastructure or Wi-Fi routers. Experimentation using power harvested from a minute solar cell was used to communicate with a base station 50 ft away. Real time operations become difficult because enough power is required in continuity to keep the device running.
With the fundamentals in the right place, the researchers are now focusing on increasing the transmission bandwidth and on encryption technology. Experimentations are for creating a low-power e-ink display phone that can be used. It could be similar to the Kindle device, but powered by radio frequencies or solar receptors.
Article by Mausam.