ChirpChirp is a script to transmit data over audio with chirp modulation.

Watch a demo on YouTube.

Requirements

ChirpChirp requires Python, Numpy, PortAudio, and PyAudio.

To install these on a Debian GNU/Linux system:

$ sudo apt-get install python python-numpy python-pyaudio

Usage

First choose a chirp, which is determined by its bounding frequencies and period (duration). For example, frequencies of 2 to 12 kHz, and a period of one eighth of a second, are a good choice.

Then start a receiving process in one terminal:

$ python -u chirpchirp.py rx 2000 12000 0.125

and a transmitting process in another terminal, with the same parameters:

$ echo Hello | python -u chirpchirp.py tx 2000 12000 0.125