You can get the slides here: UYBHYS2021-workshop-SDR.pdf
During the workshop we've used an RTL-SDR dongle to record the RF. You can get one from www.passion-radio.fr for few bucks.
wbfm.grc is a working graphflow of the WBFM receiver we built together during the workshop. It should work with your own RTL-SDR USB dongle.
If you don't have an RTL-SDR USB dongle you can use wbfm_simu.grc which generate a fake WBFM activity from two recorded file fm1.cs8 and fm2.cs8. You may need to update in the graphflow the path of this two files in the two File source blocks. Then you need to tune the parameters to hear one of the two channels and don't forget the Low Pass Filter ;)
logitechex110_dual_simu.grc is a working graphflow that demodulates the radio transmissions of a Logitech EX110 keyboard. Then additionnal processing is needed to decode the Miller encoding, process the payload and get the keystroke.
You will need to update the path to gqrx_20180105_132052_27120000_240000_fc_password.raw in the File source block. Then regerate the .py file in GNURadio (Run -> Generate or press F5) and follow the instructions:
Run the following commands in 4 terminals:
./millerudp.py 127.0.0.1 9000 127.0.0.1 1234 0
./millerudp.py 127.0.0.1 9001 127.0.0.1 1234 1
./ex110.py 127.0.0.1 1234 raw
./logitechex110_dual_simu.py
NOTE:
ex110.py may be run without 'raw' option to only show the key pressed
Launch logitechex110_dual_simu.py instead of logitech110_dual.py for simulation (playing radio record in loop)
You should see in the QT window each step of the demodulation and in the terminal the keystrokes that have been pressed:
[1] 00000 00100 001100111000⌨️ 00010100011 1010 000 ⬇️ M
[1] 00000 00100 001100111000⌨️ 00010100011 1010 000 ⬇️ M
[1] 00000 00100 001100111000⌨️ 00010100010 1001 00 ⬆️ M
[1] 00000 00100 001100111000⌨️ 00010100010 1001 00 ⬆️ M
[1] 00000 00100 001100111000⌨️ 00010110101 0101 000 ⬇️ Y
[1] 00000 00100 001100111000⌨️ 00010110101 0101 000 ⬇️ Y
[1] 00000 00100 001100111000⌨️ 00010110100 0110 000 ⬆️ Y
[1] 00000 00100 001100111000⌨️ 00010110100 0110 000 ⬆️ Y
[1] 00000 00100 001100111000⌨️ 00010001101 0001 000 ⬇️ P
[1] 00000 00100 001100111000⌨️ 00010001101 0001 000 ⬇️ P
[1] 00000 00100 001100111000⌨️ 00010001100 0010 00 ⬆️ P
[1] 00000 00100 001100111000⌨️ 00010001100 0010 00 ⬆️ P
[1] 00000 00100 001100111000⌨️ 00000010101 0001 000 ⬇️ A
[1] 00000 00100 001100111000⌨️ 00000010101 0001 000 ⬇️ A
[1] 00000 00100 001100111000⌨️ 00000010100 0010 00 ⬆️ A
[1] 00000 00100 001100111000⌨️ 00000010100 0010 00 ⬆️ A
GQRX is an SDR receiver that can be use to analyze the radio spectrum and perform basic demodulation.
GNURadio is a complete toolkit to manipulate radio signal with a python script generated from graphflow. It's also a good choice to manipulate offline RawIQ (RF recording).
Inspectrum is a tool which can be used to make a quick analyze of a radio signals such as: measuring baudrate, decoding and comparing consecutive transmissions.
RF can be recorded in various IQ files formats such as
| Format | File extension | Application |
|---|---|---|
| Complex 32-bit floating point samples | *.cf32, *.cfile | GNURadio, osmocom_fft, GQRX |
| Complex 16-bit signed integer samples | *.cs16 | BladeRF |
| Complex 8-bit signed integer samples | *.cs8 | HackRF |
| Complex 8-bit unsigned integer samples | *.cu8 | RTL-SDR |
| WAV file 16-bit stereo | *.wav | SDR# |
Conversion between these formats can be done easily with SoX see howto.
| account | subjects |
|---|---|
| @r2x0t | SpaceX Falcon video downlink decoding |
| @mrn_status | Updates from @nasa's Mars Relay Network, relaying data between Mars landers and Earth. |
| @SignalCapture | RF-Hacking Contest |
| @F5OEOEvariste | creator of RPiTX, reverse RF protocol, Digital TV and SDR |
| @rf_hacking | Various SDR topics |
| @RadioHacking | Various SDR topics (spanish) |
| @windyoona | RDS decoder, Capturing PAL video with an SDR, lot of stuffs. Check her site http://www.windytan.com |
| @FlUxIuS | Networks and computer security engineer in #Wireless systems, #SDR, #Mobile, #CarHacking and #IoT penthertz.com |
| @F4DAV | QO-100 satellite, various SDR projects |
| @furrtek | Various SDR hacking subjects like |
| @RatZillaS | PoC with SDR like 4G emergency messages or wireless backup internet in case of disaster |
| @BadgeWizard | Various SDR hack like traffic lights |
| @michaelossmann | Designer of HackRF |
| @csete | Creator of GQRX |