In this series of stories I will be going over various forms of digital modulations.
Most of the posts linked were made using an RTL-SDR device with the intent to be as accessible as possible. Any SDR should work and in the future I will be using a HackRF to broadcast data encoded.
The first step in any of this is demodulation of the original data. This can be done in two ways
- Use your SDR software to tune to the frequency you care about
- Follow step 1-4 in this post from Tomasz Watorowski
AFSK – Audio Frequency Shift Keying
This is the only one I’ve actually done