Iridium satellite cheat sheet for hackrf SDR capture using gr-iridium iridium-toolkit and iridium live

iridium-sdr.md

Description

This details how to capture voice text and rings associated with iridium satellite rebroadcasts of the Aircraft Communications Addressing and Report System (ACARS)

Prerequisites:

• Start installation in home directory preferred

  cd ~
  

• Install the following repos preferably from source or using apt in home directory or /usr/scr/:

  • gnu-radio 3.10 https://github.com/gnuradio/gnuradio

  • gr-iridium https://github.com/muccc/gr-iridium/tree/master#

  • iridium-toolkit https://github.com/muccc/iridium-toolkit

• Export path the following assumes installation of the above at user home

  export PATH=$PATH:/home/$USER/iridium-toolkit
  

• Logoff and logon to update path

Examples:

Iridium voice

Sat band voice capture of ACARS - Aircraft Comms Address and Report System

• Check configuration

  cd ~/gr-iridium/examples/*.conf
  

• Verify bias, sample rate, BW, center_freq, and gains for the sdr being used

  • Example for hackrf shown below

  [osmosdr-source]
  # Use the following if bias t is disabled
  #device_args='hackrf=0'
  # Use the following line to turn on the antenna bias
  device_args='hackrf=0,bias=1'
  
  sample_rate=10000000
  center_freq=1622000000
  bandwidth=9800000
  
  # Turn on the pre-amp
  gain=14
  
  # Moderate gains
  if_gain=40
  bb_gain=20
  

• Start the extractor

  iridium-extractor -D 4 $HOME/gr-iridium/examples/hackrf-10msps.conf > output.bits
  

  Any signals > 50% are acceptable else increase gain in conf file to achieve desired capture and restart extractor

• Start the parser of extracted files

  python3 $HOME/iridium-toolkit/iridium-parser.py output.bits > output.parsed
  

• View parse voice captures.

  python3 $HOME/iridium-toolkit/stats-voc.py output.parsed
  

• To audition voice samples left click on samples to begin and right click on sample end.

Iridium text

Sat band text message capture of ACARS - Aircraft Comms Address and Report System

• Start extraction pipe to parser

  iridium-extractor -D 4 --multi-frame $HOME/gr-iridium/examples/hackrf-10msps.conf | python3 -u $HOME/iridium-toolkit/iridium-parser.py -o zmq
  

• In a second terminal open up reassembler

  python3 -u $HOME/iridium-toolkit/reassembler.py -m acars zmq:
  

• You should see new subscriber notification in extraction pipe

• As notifications are received they will appear in the reassembler terminal

Viewer

View ACARS and sats extracted on a map

• Navigate to html index

  cd $HOME/iridium-toolkit/html
  

• Update and change line removing literal ip address to localhost 127.0.0.1 or 0.0.0.0 and change to python3. If sdr is on a remote host use its literal ip address.

  python3 m http-server --bind 127.0.0.1 8888
  

• Open a web browser using ip above to see the extractions and satellite locations on a map

Iridium RNG Alert Band

Mapping Ring Alerts with IridiumLive imager

• Edit and update script

  cd $HOME/iridium-toolkit
  

  sudo nano udp-for-il.py
  

• Change ap = to 0.0.0.0 for localhost or literal ip of the remote sdr host

• Run live extraction and viewer

  iridium-extractor --multi-frame examples/hackrf-10msps.conf | $HOME/iridium-toolkit/iridium-parser.py -p /dev/stdin /dev/stdout | python3 udp-for-il.py
  

• Verify UDP packets XXX in terminal scroll

• Start up webserver

  sudo ./iridiumlive
  

• Open browser to localhost:7777 to see rings and SATs

Special thanks to ...

• The BaldGeek
• Cemaxecuter

Photos of setup