Iridium Satellite Decoding Part 1: The Tutorial That Goes Over Your Head, Literally!

Recently I experienced an influx of emails in my inbox requesting help with Iridium decoding. So, I thought I would throw together a one or two part series on how to get started with receiving L-band signals from Iridium satellites using relatively cheap hardware and a couple of free software tools for Linux.

What is Iridium exactly? Before there was Starlink, there was Iridium! It is a low earth orbiting constellation of communication satellites providing voice and data services to the surface of the Earth. Typical applications of the Iridium network are satellite phones and internet connectivity for aircraft and marine vessels.

Join me in part one today, where I outline the hardware and software requirements for decoding Iridium and demonstrate the usage of the 'gr-iridium' software which is used for the actual capturing and recording phase of the decoding process.

In the upcoming part two video, I will be demonstrating the usage of 'Iridium-toolkit' and how it can be utilized to extract useful data from recordings of Iridium satellite data.

Thanks for watching!


DISCLAIMER:

This video was made for the purposes of education and experimentation only! Intercepting private satellite data that wasn't intended for you is illegal and punishable by hefty fines and imprisonment! You have been warned!


HARDWARE:

Airspy R2 Software Defined Radio
RTL-SDR Blog L-Band Antenna
LMR-195 Coaxial Cable
PC/Computer


SOFTWARE:

DragonOS FocalX R35
GR-Iridium


COMMANDS:

sudo nano ~/.bashrc

export PATH=$PATH:/usr/src/iridium-toolkit

SoapySDRUtil --probe

(Replace heart symbol with greater-than sign)
iridium-extractor -D 4 /usr/src/gr-iridium/examples/airspy.conf ♥ output.bits