Chirping Devices

Sending data over sound

Orlando IoT - August 2019


Chirp - Introduction

Acoustic Transmission Usecases


Using Chirp SDK in embedded devices


I'm Siva

Architect @ Computer Enterprises Inc

#Mobile #IoT #Cloud




What is Chirp?

Chirp is a communications system based on data-over-sound that is packaged as a suite of SDKs.

What does it do?

  • Chirp's data-over-sound solution enables the exchange of data between devices.
  • The data is encoded into a series of audible/inaudible tones to form a "sonic barcode".
  • The encoded data is sent over air, to a receiving device or group of devices where the data is then decoded.

Transmitter, Channel & Receiver

  • The transmitter is a device (e.g. a mobile phone, embedded board, laptop) containing audio output, loudspeaker(s) and running the Chirp SDK
  • The channel is typically an acoustic environment or any medium that is able to carry audio.
  • The receiver is a device containing audio input, microphone(s) and running the Chirp SDK

Encoding / Decoding

  • Chirp uses Frequency Shift Keying for its modulation scheme. Chirp uses an M-ary FSK scheme, encoding input symbols as one of M unique frequencies.
  • Patented DSP methods for removal of acoustic artifacts and environmental effects.
  • Error detection (CRC) and error correction (Reed-Solomon)

Transmission Rate


In typical real-world environments, Chirp can transmit at approximately the following rates:


  • 1000bps at NFC range (30cm)
  • 150bps at peer-to-peer range (3m)
  • 15bps at long range (100m)


Both Audible & Ultrasonic frequencies are supported.

By default, four protocols are available to use:

  • standard: audible transmission, for peer-to-peer ranges
  • ultrasonic: inaudible transmission, for peer-to-peer ranges
  • 16kHz: intended for embedded devices supporting a 16kHz sample rate
  • 16kHz-mono: intended for embedded devices supporting a 16kHz sample rate

Acoustic Transmission Use cases


Create fast, secure transactions without a network connection. From ticketing to payments, Chirp connects devices using audible or inaudible frequencies to transmit sensitive data for authentication.


Enable zero-friction, proximity-aware M2M connectivity by integrating Chirp into your embedded devices


Discover nearby devices and create seamless, secure connections to broadcast informations, build user groups or transmit data within a smart home or office

Enabling toys to interact with content on any device, Hijinx launched this technology powered by Chirp into the official Beat Bugs toys to accompany the Netflix series.

Using Chirp SDKs


Dev Brand Colors


Action Items

- Learn and explore Chirp - Data over sound

- Be Kind & Spread Your Awesomeness ...

- Let's break and build



Thank you !!!

Chirping Devices

By Sivamuthu Kumar

Chirping Devices

Chirping Devices - Sending Data Over Sound - Orlando IoT Meetup Group August 2019

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