Researchers have discovered a way to capture and harness energy transmitted by radio and television transmitters, cell phone networks and satellite communications systems. By scavenging this ambient energy from the air around us, the technique could provide a new way to power networks of wireless sensors, microprocessors and communications chips.Manos Tentzeris, a professor in the Georgia Tech School of Electrical and Computer Engineering, and his team are using inkjet printers to combine sensors, antennas and energy-scavenging capabilities on paper or flexible polymers. The resulting self-powered wireless sensors could be used for chemical, biological, heat and stress sensing for defense and industry, radio-frequency identification (RFID) tagging for manufacturing and shipping and monitoring tasks in many fields including communications and power usage. Communications devices transmit energy in many different frequency ranges, or bands. The team’s scavenging devices can capture this energy, convert it from AC to DC, and then store it in capacitors and batteries. The scavenging technology can take advantage presently of frequencies from FM radio to radar, a range spanning 100 megahertz (MHz) to 15 gigahertz (GHz) or higher. The researchers have already successfully operated a temperature sensor using electromagnetic energy captured from a television station that was half a kilometer distant. They are preparing another demonstration in which a microprocessor-based microcontroller would be activated simply by holding it in the air.Learn more from Georgia Tech.
Ambient Electromagnetic Energy Harnessed for Small Electronic Devices
