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// Reliable Data-Over-Audio Solutions made in Germany!

Sonix Link

Sonix Link uses ultrasonic, inaudible sound to connect devices without  having to rely on Wi-Fi or Bluetooth.

Push Notifications

Broadcast Notifications to Smartphones within a given range.

Data Transfer

Transfer data across multiple devices in a private and secure way.

Ultrasonic Location

Locate Devices even inside buildings with high accuracy.

Presence Verification

Automatically log in and out with ultrasound ID tones.


Use an ultrasonic key to claim access to your digital vault.

Device Synchronization

Synchronize thousands of smartphones using ultrasound.

Why Sonix Link?


Flexibility to support encryption, cryptography, key exchange alongside full duplex, multi-channel features, we can enable the most secure transmission method.


Our clients have complete control of their data transmission experience based on their transport layer and business model.


Customizable performance range from a few centimeters to many meters with best in class transmission reliability and confirmation.


Faster and more seamless authentication experiences enabled with the combination of range and experience control.

Low Cost

Flexibility to support favorable transaction fee and cost structures in payment experiences due to security & control.

Low Power

For IOT Solutions power efficientcy is very important. Therefore our Low-Power Receiver Technology is well suited.

// Some Use Cases for our Ultrasound Communication Technology


Ultrasonic Data Transfer

Send arbitrary data payloads through sound waves. Our Ultrasonic Data Transfer protocol is resilient to noisy environments, including large stadiums, and can transmit over 100 meters. The data payload can then be leveraged to achieve any custom, desirable action on the receiving device.

UDT is extremely secure, as the signal is isolated to the room in which it is broadcasted. As the UDT signal never occupies the electromagnetic spectrum (think Wi-Fi, cellular service and Bluetooth), it is impenetrable to many traditional hacking techniques. Traditional encryption methods like SHA-256 can be applied to the data as an additional layer of security.

Ultrasonic Location

GPS and BLE location services provide only rough approximations of user location, especially indoors. Sonix Link Wayfinding (UWF) services allow positional triangulation, using only existing speaker infrastructure — no additional hardware required.

Tailored content can be displayed depending on the user’s current location, or referencing previous regions he or she has visited.

Ultrasonic Authentication

Any user ID, password or username can be transmitted via Sonix Link Authentication Protocol. A typical concert ticket can be transmitted in roughly one tenth of a second. This can help speed up long queues for check-ins and even eliminate specialized ticket scanners.

Ultrasonic for Mobility

If you are interested in using our technology in a mobility project, please contact our partner BeeSonix.

Sonix Link SDK

Available for immediate implementation, Sonix Link’s unique signal processing algorithms are wrapped in an SDK that enables cross-platform, cross-OS solutions for all sonic and ultrasonic use cases.

The Sonix Link Technology Core is wrapped in an SDK that enables cross-platform, cross-OS solutions for all sonic and ultrasonic connectivity use cases.

Sonix Link provides a development wrapper for the SDK for every common development environment, including Android, iOS, Java, React Native ,C#, C++, Node.js and Flutter.
A development wrapper for any niche or proprietary development environment can be created as needed.

// A brief overview on our Ultrasound Communication Technology


How Does it Work?

In short, data-over-sound enables the exchange of data between any devices with a pre-existing loudspeaker or microphone through sound waves. Delivered through machine-to-machine communications software, the technology works like an audio QR code, sending data over an acoustic channel to enhance end-user experiences and add value to existing hardware.

In practice, data is encoded into an acoustic signal—a series of audible or inaudible pitches and tones to form a kind of “sonic barcode.” This is then played into a space (usually air, but could be VoIP stream or wired telephone lines) and received and demodulated by a “listening” device. Data is subsequently decoded by the receiving device, or group of devices, and returns the original data.

By using a range of audio frequencies, programmers can fit more information into less audio. To filter out noise, developers carefully select frequencies and tune their software so that their applications can speak to each other to detect and decode data signals in noisy environments, like a busy train platform or concert venue.

Its potential as a form of frictionless, low-power connectivity, when applied to various areas within the IoT, audio, and voice landscapes, is coming to the forefront in a growing number of use cases. So much so that it’s increasingly establishing itself as an integral tool for seamless ultrasonic data transfer in both an industrial and hobbyist developer setting.

Why Sound?

There are very clear and practical affordances of data over sound. From its seamless integration into existing hardware and frictionless connections, to its ability to work offline in even the most extreme environments, there’s myriad potential use cases for data-over-sound.

Data-over-sound has a multitude of complementary capabilities when compared to other connectivity technologies. The technology’s position as a pairing-free, one-to-many medium means it mitigates some of the setup and provisioning pain points often associated with traditional alternatives such as Bluetooth and Wi-Fi, presenting an appealing and versatile solution for frictionless data transmission. In general, compared to other technologies, data-over-sound is also able to be used in very wide application areas, taking advantage of existing hardware and without prior setup or configuration.

Doing so, it enables the interconnection of millions of devices in a seamless, scalable, and cost-effective way to enhance end-user experience and drive value without increasing hardware costs. This ability to enhance existing infrastructure has inevitably captured the interest of companies interested in adding wireless connectivity functionality without adding to their bill of materials.

The future for seamlessly connected devices lies in utilizing a broad range of connectivity solutions, including data-over-sound, where each technology complements the others in the suite. Working in conjunction with other solutions, data-over-sound exists as an essential component of fulfilling the promise of ubiquitous, frictionless connectivity.

The Benefits of Sending Data over Sound

Embedding and extracting meaning from sound provides a quick, secure, and cost-effective solution that works completely offline. Inevitably, there’s no “one-size-fits-all” data-transfer solution that will be optimal in all environments and purposes. Yet, in many situations, data-over-sound is now emerging as an ideal medium for simple implementation and reliable connectivity.  Some of the most clear affordances of sound include:

Works offline: Sound works peer-to-peer, or one-to-many, meaning no additional connections are needed to “the cloud” or other network services. Thus, data-over-sound software works well in a situation where there’s no network access, like rural or RF-restricted areas.

Utilize existing hardware: The rise of microphones in IoT devices means that the hardware requirements are already met for billions of existing devices of all form factors. Combined with the arrival of zero-power microphones, data-over-sound provides an extremely low power, “always connected,” device-to-device data-transfer solution. Eliminating the need for additional hardware saves users both money and resources that can be invested back into the business.

Secure, private data transfer: Because acoustic connection doesn’t require an internet connection and supports industry-standard cryptography, you’ll have peace of mind that any data transferred will not be compromised. No audio, not even audio metadata, is ever stored or sent from a receiving device for processing.

Supports range of platforms: Data-over-sound is compatible with machines and devices of different platforms, form factors, and architectures that can process audio. From smartphones and tablets to toys and games, and even legacy and analog equipment, any device with a microphone and speaker can receive and decode data with the technology.

Seamless integration: Often implementing new software can be resource- and time-intensive. However, data-over-sound can be delivered through software-development kits (SDKs), which provides a fast and easy integration to a host of platform types, making the solution ideal for hobbyist developers and IoT projects.

Scalable: With data-over-sound, there’s no need to reengineer as your application grows. Whether the aim is to enable seamless P2P exchanges or send data from one-to-many, this method of data transfer is completely scalable. Use cases for data-over-sound are therefore wide ranging. They can include IoT devices sending and receiving commands, secure transactions, and un-spoofable receipts to merchants or buyers, as well as sending/receiving credentials (to provision Wi-Fi, for example).

Works in extreme environments: Through a range of frequencies, data-over-sound software is robust to background noise and has been proven to work seamlessly in the most extreme environments. From the streets of Delhi to nuclear power stations, acoustic network connectivity remains universally strong in the toughest environments.

Like every other industry, the world of data and connectivity is becoming increasingly intricate, as new devices emerge and businesses look for new ways to communicate effectively. Data-over-sound is now putting a spotlight on the huge potential of audio as a true medium for fast and secure data transfer. And it can work in collaboration with other technologies to deliver ubiquitous interactions between devices for all purposes and environments.

Sonix Link QR Bluetooth Wi-Fi ZigBee 802.15.4 LoRa
One-to-many broadcast
Non-line-of-sight transmission
Works in RF-restriced environments
Zero configuration
Low-power operation
Supported by low-end mobile devices
Typical maximum range 100m 10:1 100m 50m 100m 10km
// Advice and answers from the Sonix Link Team

Frequently Asked Questions

Is there extra hardware required to use Sonix Link?

No, all that is required to use our technology is a smartphone with a Sonix Link-integrated app downloaded to it, and a nearby speaker to play an audio file embedded with one of our triggers.

What file formats can Sonix Link operate in?

Sonix Link's ultrasonic signals successfully operate in most lossless and lossy file formats, including WAV, AC3, AAC, FLAC, and MP3.

What does “ultrasonic” mean?

Ultrasonic refers to any sound wave above the human hearing level. Generally, people can’t hear sound waves transmitted above 15 kilohertz, so Sonix Link embeds data in an audio file between 19.0 and 20.5 kilohertz, making it inaudible to over 97% of the population.

Does the ultrasound cause problems for the use of hearing aids?

No, it does not exist. Hearing aids according to DIN EN 60118-0 no longer transmit sounds in the range above 8 kHz to any significant extent. On the contrary: our technology is also an opportunity for those who have limited hearing, since information can be accessed on smartphones.

Does the ultrasound cause problems for animals?

No, the technology is harmless to animals. Certain animals can hear the sounds, but they are not affected by it.

How does my phone sync with the audio?

Sonix Link’s integration with your app (whether it’s existing or we create one for you) activates a device’s microphone and listens for the trigger embedded within the audio file.

What is the maximum range of the Sonix Link system?

Sonix Link’s range is determined by volume: the louder your speaker system, the farther the data will travel to mobile devices. Our signals have successfully transmitted over 10m smartphone to smartphone or even over 100m from speaker system to smartphone.

How much does it cost to use Sonix Link?

Cost is determined based on which product(s) you choose and your number of potential users. Let us know if you’d like a customized quote.

What’s the turnaround time required to launch a Sonix Link project?

Sonix Link requires at least three weeks of lead time, but more time may be necessary depending upon the product(s) you select and the complexity of the project.

Still have questions? Get in touch