• Python (2.7)
• NumPy (scipy)

Unless otherwise noted in a file, everything here is (c) Sec & schneider and licensed under the 2-Clause BSD License

Note: The rad1o has to be in hackrf-mode

hackrf_transfer  -r /dev/stdout -f 1627000000 -a 1 -l 40 -g 20 -s 2000000 | python2 extractor.py -c 1627000000 -r 2000000 -f hackrf --jobs 2 | grep "A:OK" | tee outfile

This writes to outfile. Pager messages can be decoded with

python2 iridium-parser.py outfile

To capture and demodulate Iridium packets use extractor.py. You can either process a file offline or stream data into the tool.

By default, the extractor will drop samples if the computing power available is not enough to keep up. If you have an already recorded file, use the -o,--offline option to not drop any samples. In this case the extractor will pause reading the file (or input stream) until it can process more samples again.

The internal queue is filled with samples where the detector has detected activity in the file. By default it is 12000 elements long (roughly 4 GB at 2 Maps). You can tweak the length of the queue with this option

The center frequency of the samples data in Hz.

The sample rate of the samples in sps

The number of processes to spawn which demodulate packets. The detector runs in the main process.

detector-fft.py

Searches through the file in 1 ms steps to scan for activity and copies these parts into snippets called <rawfilename>-<timestamp>.det

cut-and-downmix.py

Mixes the signal down to 0 Hz and cuts the beginning to match the signal exactly. Output is <detfile>-f<frequency>.cut

demod.py

Does manual DQPSK demodulation of the signal and outputs <cutfile>.peaks (for debugging) <cutfile>.data the raw bit stream and on stdout an ASCII summary line.

iridium-parser.py

Takes the demodulated bits and tries to parse them into a readable format.

Supports some different output formats (-o option).