Researchers from the National University of Singapore, together with scientists from Tohoku University in Japan and the University of Messina in Italy, have developed a wireless technology that allows low-power devices to be powered by radio and Wi-Fi signals. Industrial use of this discovery could potentially reduce the reliance of low-power devices on batteries or external power.

The energy harvesting module (EHV) that the scientists developed will convert radio frequency signals, which the researchers call “waste energy,” into direct current. The technology helps harvest energy from radio signals, which can be used to power low-power devices such as temperature sensors.

The researchers said they were able to optimize the spin rectifiers to operate at low-power levels of radio signals in the environment. They then integrated an array of these spin rectifiers into an energy-harvesting module to power the LED and commercial sensor at signal strengths below -20 dBm.

Reference: decibel (dB) is the ratio of the power of the measured signal to the fundamental power. dBm is the same as dB, but based on a signal with a power of 1 milliwatt (mW).

Currently, commercial use of the new technology is limited to the design of conventional rectifiers due to thermodynamic limitations at low power. The solution could be a spin rectifier (SR) created using nanotechnology, which would provide optimum conversion of the wireless signal into direct current. This would allow electricity to be collected from surrounding radio waves in the power range of -62 to -20 dBm. The researchers are also investigating the possibility of integrating an antenna on a chip to increase efficiency.

Numerous studies on radio frequency energy harvesting (RF-EH) technology show that it is possible to harvest energy from LTE, DTV, GSM, WLAN, HIPERLAN and C-Band radio signals, which are widely used in urban and suburban areas. The application of the new technology will help to efficiently extract energy from radio signals, use it to power various sensors and create new types of devices for commercial, scientific and medical applications.

The researchers emphasized that the technology they developed helps reduce battery dependency, reduce environmental impact, extend the life of devices and create new types of wireless sensor networks and Internet of Things devices. Source