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Welcome to IridiumLive!

IridiumLive is a Blazor server application which allows for the real-time vizualization of the iridium satellites as they pass above your location.

It is another tool which allows for the visualization of live data coming from gr-iridium. Will not work without it.

You install the application in your local network, and use the browser to interact with it.



To build/run from source you need dotnet version 3.1.* installed, then run:

git clone
cd iridiumlive
cd IridiumLive
dotnet run

At this time the following ports have been hard coded:

 7777: IridiumLive server port,
15007: udp port for receiving data from gr-iridium and iridium-toolkit.

If the ports cannot be bound to, use:

lsof -i :7777
lsof -i :15007

to find out what's attached to these port(s).

You could use:

lsof -ti :7777 | xargs --no-run-if-empty kill -9

to forcefully clear out the port as part of your pre-start routine.

The data will be provided by your personal install of gr-iridium and iridium-toolkit (see gr-iridium and iridium-toolkit). See bottom of page for quick instructions.

  1. On the same machine as gr-iridium download and extract the python udp transmitter Please install in the same folder as gr-iridium.
  2. Depending of your intended OS target, download and extract the appropriate IridiumLive archive. There is no installation needed, simply extract in a folder of its own. You can extract either on the same machine or to a different one.
  3. In the script, the server_address ( denotes the machine where IridiumLive is installed. Modify it accordingly. This address is also where you will open your browser to later on:
import socket

ap = ("", 15007)
sk = socket.socket(family=socket.AF_INET, type=socket.SOCK_DGRAM)
def sendOverUdp(line):
  1. Change the center frequency of the gr-iridium decoder to include the Ring Alert band as described at min 9 in the Stefan “Sec” Zehl, schneider during their presentation at The Eleventh HOPE (2016): Iridium Satellite Hacking.
  2. Instantiate the iridium receiver and pipe through decoder, filter and udp transmitter adapting the following command line:
user@computer:~/gr-iridium$ iridium-extractor --offline --multi-frame examples/hackrf.conf | ~/iridium-toolkit/ -p /dev/stdin /dev/stdout | python
  1. Only continue to next step if you see udp lines being transmitted:
1576397118 | i:  68/s | i_avg:  19/s | q:    0 | q_max:    7 | o: 106/s | ok:  63% | ok:  43/s | ok_avg:  51% | ok:      32064 | ok_avg:   9/s | d: 0
1576397119 | i:  67/s | i_avg:  19/s | q:    0 | q_max:    6 | o: 103/s | ok:  64% | ok:  43/s | ok_avg:  51% | ok:      32108 | ok_avg:   9/s | d: 0
1576397120 | i:  58/s | i_avg:  19/s | q:    0 | q_max:    5 | o:  91/s | ok:  57% | ok:  33/s | ok_avg:  51% | ok:      32142 | ok_avg:   9/s | d: 0
1576397121 | i:  69/s | i_avg:  19/s | q:    0 | q_max:    4 | o: 115/s | ok:  61% | ok:  42/s | ok_avg:  51% | ok:      32185 | ok_avg:   9/s | d: 0
169 <- the length of one blob sent over UDP
  1. Run IridiumLive.
  2. Set up time accurately on the gr-iridium machine!
  3. Open any browser at http://server_address:7777 and enjoy!



This was my first .NET Core web app. Blazor on top of it. Be merciless and gentle!


Quick install on gr-iridium and iridium-toolkit for Rapberry Pi

The following has been tested on RPi 400 with
Currently DragonOs contains gnuradio 3.8+
Use the following to have your gr-iridium aligned with these versions:

git clone -b maint-3.8
cd gr-iridium
mkdir build
cd build
cmake ..
sudo make install
sudo ldconfig

git clone
git checkout -b local-branch-from-commit e173069f43189ee7dfca2875f56ac284e74b17e4