R2D2

Inspiration

There are many advantages of using the sound spectrum for communication, especially for lower-datarate applications such as authentication, messaging, and IoT connectivity. Furthermore, it is a relatively convenient and secure way of passing important information at short ranges since the volume of the speaker can be easily controlled and traffic does not have to pass through Wi-Fi channels.

Many devices also use speakers and microphones that can recognize frequencies in the audible spectrum, making audible-frequency applications very portable.

What it does

R2D2 sends and receives messages using brief bursts of audible noise, enabling devices to communicate locally without reliance on any networks like Wi-Fi, LTE, etc.

How we built it

Using Android Studio and a library for performing signal processing on microphone inputs, we were able to extract the pitch of frequencies being heard with confidence levels.

Challenges we ran into

Performing consistently within noisy environments and finding resources on signal processing were the most challenging aspects of the project for us.

Accomplishments that we're proud of

We learned a lot about signal processing (how Free Fourier Transforms and spectrum analyzers work) and built something useful/interesting.

What we learned

Perseverance can work wonders. At many points throughout the hackathon, many of us were not sure whether the project would work.

What's next for R2D2

The next step would be to apply sound transmission to more things, such as authentication.

Built With

• android-studio
• chirp