How Does Data over Audio Transmission Work?

Ultrasonic or data over audio transmission offers an incredible number of applications that range from facilitating peer to peer payments, to delivering timely mobile app promotions, to offering consumers a frictionless purchase experience. As a consumer, we’re often struck by the “tech”, but unclear on how exactly it works. For the most part, consumers don’t really care, but our customers do (as does anyone who likes taking things apart).

With that in mind, we’re going to break down how ultrasonic audio transmissions work. LISNR inserts data into a soundwave that we call a “tone”, which can be broken down into three components: preamble, header, and payload. Each time that data is sent ultrasonically, LISNR generates a tone (locally in an app via our SDK, or online through our API) that can be emitted from a speaker (in a mobile device or amplified through a speaker like those in a high quality portable speaker, for instance) and “heard” by one or more devices via a standard microphone. The three components of the tone are:

1. Preamble

The preamble is the first part of the data over audio transmission signal that announces the presence of a data enabled tone, but does not include any data. This notifies the receiving device that it will need to start decoding data from the subsequent part of the tone. For example, when a delivery person rings your doorbell, you become aware that they are present and would like you to answer the door to accept the delivery.

2. Header

The header contains metadata about the information being sent in the next portion, called the payload. This information tells the receiving device the payload size, as well as the tone type (such as ID, text, or data).

3. Payload

The payload is the portion of the tone that contains the data you want the end user to receive. For example, the sender could transmit a message that said “Hi Kevin! Welcome to Macy’s. Get 20% off Halloween products today.” Or it could send an encrypted message that contained the 16 digit credit card number you have in your mobile wallet. It’s important to understand that information such as the payload size and LISNR tone profile can impact the speed of data transfer.

Next Steps with Data Over Audio Transmission

Today we’ve gone over the basic structure of your LISNR ultrasonic data transmission. While there are a multitude of applications for the technology and platform, we’ve begun to focus our solution in the payments, retail customer journey, and transportation customer journey areas. If you’re looking to take your offering in one of those areas to the next level, we would be excited to talk to you about your next steps.

Want to learn more about how data over audio transmission works? Get in touch to connect with our team to explore how data over audio can help your business.