Scientists from Sandia National Laboratories have built what they called the world’s smallest and best acoustic amplifier. Interestingly, the team leveraged a concept that was virtually abandoned five decades ago. The paper the researchers published about their breakthrough shows the device is more than ten times more effective than earlier versions of the design.
The significantly improved acoustic amplifier could result in smaller wireless technology in the future. One example of potential use is smartphones, which are packed with radios today that send and receive data and phone calls. Inside the smartphones we hold in our hands are all manner of electronic components, including amplifiers that could potentially be made smaller and better as acoustic devices.
If those amplifiers are made acoustic rather than electronic, they would use soundwaves instead of electrons to process radio signals. Scientist Lisa Hackett was one of the team members and said that acoustic wave devices are inherently compact because the wavelengths of sound at these frequencies are small. The acoustic amplifier developed at the lab is a 276-megahertz amplifier that is only 0.0008 square inch and demonstrates what the team says is a vast and largely untapped potential for making radios smaller through acoustics.
The team says that the two gigahertz frequencies that would need to be amplified for a cellular device would allow the device to be even smaller, measuring 0.00003 square inch. The amplifier would fit comfortably inside a grain of table salt at that footprint, making it more than ten times smaller than current state-of-the-art technologies.
Smaller components are a big deal because they lead to smaller smartphones and electronic devices in general. Along with the amplifier, the team created the first acoustic circulator, another crucial radio component responsible for separating transmitted and received signals. Another scientist on the project, Matt Eichenfield, says that the team is the first to show it’s practical to make the functions normally done in the electronic domain in the acoustic domain.