Researchers at Sandia National Laboratories have built what they call the smallest and best acoustic amplifier in the world. Interestingly, the team used a concept that was practically abandoned five decades ago. A paper published by scientists on their breakthrough shows that the device is more than ten times more effective than earlier versions of the design.
A significantly improved acoustic amplifier could result in less wireless technology in the future. One example of potential use is smartphones, which today are filled with two-way radios that send and receive data and phone calls. Inside the smartphones we hold in our hands are all kinds of electronic components, including amplifiers that could potentially be smaller and better as acoustic devices. If these amplifiers are made acoustically rather than electronically, they would use sound waves instead of electrons to process radio signals.
Scientist Lisa Hackett was one of the team members and found that acoustic wave devices are inherently compact because the sound wavelengths at these frequencies are small. The acoustic amplifier developed in the lab is a 276 megahertz amplifier that is only 0.0008 square inches and shows what the team says is a huge and largely untapped radio shrink potential with acoustics. The team says that two Gigahertz frequencies would be needed, the gain for a cellular device would allow the device to be even smaller, measuring 0.00003 square inches. The amplifier would fit comfortably into a grain of table salt on this base, making it more than ten times smaller than current state-of-the-art technology. Smaller components are a big deal as they lead to smaller smartphones and electronic devices in general.
Together with the amplifier, the team created the first acoustic circulator, another key radio component responsible for separating transmitted and received signals. Another researcher on the project, Matt Eichenfield, says the team was the first to show that it is practical to perform functions normally performed in the electronic domain in the acoustic domain.
