APPLICATIONS OF TECHNOLOGY:
- Communication
- Ultrasonic wave emission and reception
- Distance measurement tool
ADVANTAGES:
- Reliable, highly directional
- Wide equalized frequency response and high sensitivity
- No interference with voice communication
- Low cost fabrication method
ABSTRACT:
A research team led by Berkeley Lab’s Alex Zettl has invented a wideband ultrasonic radio, with graphene-based electrostatic acoustic wave generators/receivers, that can be used in communication to provide a wide frequency span for emission and reception of data. The Berkeley Lab ultrasonic radio can also be used for distance measurement with sub-millimeter accuracy.
Graphene’s ultra-low mass and high mechanical strength make it an excellent material for sound transduction. The radio’s microphone has an outstanding equalized frequency response covering from at least 20 Hz to 0.5 MHz and an unparalleled sensitivity able to record, for example, bats’ ultrasonic waves in the wild.
Ultrasonic waves suffer no disturbance from audible frequencies and, unlike electro-magnetic waves, propagate well in conductive materials. Conventional transducer technologies operate at limited frequencies and set an upper bound on the frequency response. The Berkeley Lab invention, however, provides a low-cost, reliable, and highly directional communication method with a wide frequency span.
DEVELOPMENT STAGE: Successful frequency sweeping of ultrasonic bat calls. Proven amplitude modulated transmission of information at 0.3 MHz.
STATUS: Published PCT Patent Application US2016/019,373 (Publication WO2016/148860). Available for licensing or collaborative research.
SEE THESE OTHER BERKELEY LAB TECHNOLOGIES IN THIS FIELD:
Nanotube Radio for Communications and Medical Applications, IB-2431, 2432
Electrostatic Graphene Loudspeaker, IB 2013-030
REFERENCE NUMBER: 2015-076