Defying the spectrum

Qspectrum

#git clone https://github.com/xmikos/qspectrumanalyzer.git
#less README.rst #--> Ubuntu
#apt install python3-pyqt5 python3-pyqtgraph

apt install python3-pip
pip3 install qspectrumanalyzer

which hackrf_sweep
qspectrumanalyzer 

File > Settings
settings/Backend: hackrf_sweep
settings/Sample rate: 20 Mhz

Frequency: 10 or 450 - 7250 Mhz
Bin size:  1000 kHz

-MAIN CURVE
MAX HOLD
AVERAGE
SMOOTHING

Inspectrum

Grab and build Inspectrum

apt install qt5-default libfftw3-dev cmake pkg-config libliquid-dev

git clone https://github.com/miek/inspectrum.git
cd inspectrum/
mkdir build/
cd build/
cmake ..
make -j8
make install

freq=`arfcncalc -a $arfcn -d`
hackrf_transfer -h
hackrf_transfer -r air.cs8 -f $freq -a 1 -l 32 -g 20 -s 2e6 -n 20000000
#-C "$hppm"

as user

inspectrum --rate 2e6 air.cs8
inspectrum --rate 12e6 tele2hop.hrf.cs8

WARNING: cs8 FILE EXTENSION MATTERS!!!

Troubles

Couldn't transfer any bytes for one second.

==> reset the device once and you’re good

Spectrum Analyzer GUI for hackrf_sweep

Fetch hackrf-spectrum-analyzer

sudo apt install build-essential ant git libusb-1.0 libfftw3 libfftw3-dev openjdk-8-jdk

git clone --depth=1 --recurse-submodules https://github.com/pavsa/hackrf-spectrum-analyzer.git
cd hackrf-spectrum-analyzer/src/hackrf-sweep/
make -j8
build/hackrf_sweep_spectrum_analyzer.sh

Review signals w/ Octave

apt install octave octave-signal octave-communications
#wget "https://raw.githubusercontent.com/UpYou/gnuradio-tools/master/matlab/read_complex_binary.m"
wget https://github.com/UpYou/gnuradio-tools/raw/master/matlab/read_complex_binary.m
octave-cli

x=read_complex_binary('/root/capture/23.cfile');
plot(abs(x(100001:200000)));

pkg load communications
imagesc(vec2mat(20*log10(abs(x(1:end))),625),[-50,0])

Resources

inspectrum

https://github.com/miek/inspectrum/wiki/Build