swkrueger/thrifty

Thrifty is proof-of-concept SDR software for TDOA positioning using inexpensive SDR hardware such as the RTL-SDR.

thrifty's Issues

Fastcard Segmentation fault on NixOS

We have ourselves a Hiesenbug 👻

I realize NixOS isn't "officially" supported by this project, but I'm still going to try getting it going (NixOS makes deployment to Raspberry Pi very nice).

Any ideas on where this segmentation fault might be coming from would be very appreciated. I've documented my research below.

I've compiled fastcard using CMake, using the most recent libraries available on NixOS unstable. That is fftw-3.3.8 and gnuradio-3.7.13.4 (libvolk). Ubuntu 16 has fftw-3.3.4 and libvolk-1.2.1. I've also tried using libvolk-1.2.1 with no luck.

Clue # 1 is the segfault occurs when calling a function from libvolk:

Thrifty/fastcard/fastcard.c

Line 180 in 2ad9775

volk_32fc_magnitude_squared_32f_a(d->fft_power,

Clue # 2 is that fastcard does not segfault when the block size is set to less than 4096

$ ./fastcard -i rtlsdr -b 4095 -h 4000
# works..

$ ./fastcard -i rtlsdr -b 4096 -h 4000
# ...snip...
# Segmentation Fault

Clue # 3 is that fastcard does not segfault inside valgrind

$ valgrind ./fastcard -i rtlsdr
# works...

My hunch is that it has to do with the two newer library versions. Its even possible that this bug is not occurring in this projects code. But if something comes to mind, it would be great to see this project running on Nix 💟

Explanation of detector parameters

Could you explain these parameters in detector.cfg

capture_skip:  20000
block_size: 16384
block_history: 4920
carrier_window: 7 - 110
carrier_threshold: 15 * snr
corr_threshold: 15 * snr

I would like to better understand the parameters to fine tune the detector for my experiment with my new tracking tag.

when run thrifty can't open shared object file :libfastcard.so

run: thrifty capture rx1.card (I removed -o )
when run
pi@rpi-rx1:~/thrifty/example $ thrifty capture rx0.card
fastcard: error while loading shared libraries: libfastcard.so: cannot open shared object file: No such file or directory

Error while building fastcard

Hi there, great project!

as I am trying to -make- fastcard I am getting the following error:

pi@rpi-rx1:~/build/fastcard $ make
[ 86%] Built target fastcard
[ 93%] Linking C executable fastcard
libfastcard.so: undefined reference to `rtlsdr_set_bias_tee'
collect2: error: ld returned 1 exit status
CMakeFiles/fastcard_bin.dir/build.make:98: recipe for target 'fastcard' failed
make[2]: *** [fastcard] Error 1
CMakeFiles/Makefile2:136: recipe for target 'CMakeFiles/fastcard_bin.dir/all' failed
make[1]: *** [CMakeFiles/fastcard_bin.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2

Do you have any idea why this is happening?

Error when building fastdet

Hi there I am unable to compile fastdet

On a Pi 3 Raspbian Stretch 4.9.41-v7+
After following the pi3 install guide
When trying to make fastdet

[ 20%] Building CXX object CMakeFiles/fastdet.dir/corr_detector.cpp.o
/tmp/Thrifty/fastdet/corr_detector.cpp: In member function ‘CorrDetection CorrDetector::detect(const std::complex<float>*, float)’:
/tmp/Thrifty/fastdet/corr_detector.cpp:153:35: error: cannot convert ‘unsigned int*’ to ‘uint16_t* {aka short unsigned int*}’ in argument passing
             stop_idx_ - start_idx_);
                                   ^
CMakeFiles/fastdet.dir/build.make:62: recipe for target 'CMakeFiles/fastdet.dir/corr_detector.cpp.o' failed
make[2]: *** [CMakeFiles/fastdet.dir/corr_detector.cpp.o] Error 1
CMakeFiles/Makefile2:99: recipe for target 'CMakeFiles/fastdet.dir/all' failed
make[1]: *** [CMakeFiles/fastdet.dir/all] Error 2
Makefile:127: recipe for target 'all' failed
make: *** [all] Error 2

Availablity of testing signals

Are there any testing signals available that I can transmit with a second RF frontend to test the receiver?
Or maybe a script to generate such signals? I have a RTLSDR that I want to use as a thrifty receiver and a HackRF One that I would like to use for signal transmission. From a quick look at your thesis I believe that you are using OOK modulation? What are the exact parameters for the Gold code expected by Thrifty?

Usage example in README is broken

I am getting the following error when trying to run the example:

$ thrifty capture -o rx0.card
thrifty capture: error: unrecognized arguments: -o

Could it be that the instructions are outdated?