Tetra decoding

[hansheesbeen]

I will change back to mint. Don't like debian for now. Keep you informed...

 

[sq5bpf]

i've posted updated instructions and scripts to the repository.

thanks to everyone for catching the errors

 

[hansheesbeen]

Back again on Linux Mint 17 32 Bit:

Script started on Wed Nov 26 16:31:37 2014
hans@LIN-Hans //home/hans/libosmocore-sq5bpf/telive $ sudo make
[sudo] password for hans:
gcc telive.c -o telive -lncurses -g
telive.c:23:21: fatal error: ncurses.h: No such file or directory
#include <ncurses.h>
^
compilation terminated.
make: *** [telive] Error 1
hans@LIN-Hans //home/hans/libosmocore-sq5bpf/telive $ exit
exit

Script done on Wed Nov 26 16:31:50 2014

 

[sq5bpf]

$ sudo make
[sudo] password for hans:

you can compile as your regular user, there is no need to run as root (but this will work too)

gcc telive.c -o telive -lncurses -g
telive.c:23:21: fatal error: ncurses.h: No such file or directory
#include <ncurses.h>

you don't have the ncurses development libraries. under debian it's called libncurses-dev, probably something similar under debian-derived distros

added this to the documentation, thanks

 

[sq5bpf]

i've just pushed a major update to osmocom-tetra-sq5bpf (had one file from an older version, and basically almost didn't work), please git clone again and recompile

 

[yo4tnv]

Thank you Jacek !
Indeed, an early Christmas present
I had some attempts few moths ago on Xubuntu/64, but i was stuck because of poor reception condition here in my qth, messed gnuradio 3.7 and python scripts. I`ll try again using this code, and keep you updated, of course

73 !

 

[molay]

I would like to thank sq5bpf to make public its code.

 

[sq5bpf]

there is another tutorial on how to begin using this software (much simpler than what i would be able to write

RTL-SDR Tutorial: Listening to TETRA Radio Channels - rtl-sdr.com

thanks for writing it!

beware that the software really likes to eat cpu, especially on multiple channels, so running in a virtual machine is fine to get a taste of the software but might not be enough for serious work

 

[sq5bpf]

i've pushed revised documentation to the telive repository, hopefully this will be clearer.

i have a question - is there any function in a program like this that would be useful for a person that installs/manages tetra networks?

 

[systron]

dsd+ tetra decoding

i hope that dsd+ will decode tetra soon...

any live tetra systems in the united states ?

 

[KD4YGG]

Yes - Diverse Power near LaGrange, Georgia.

Harris County Georgia public safety reported to be utilizing the system.

 

[sq5bpf]

i hope that dsd+ will decode tetra soon..

the osmocom-tetra software is under the affero gplv3 license, so to do this legally the dsd+ source should be made public. which would be a great idea btw.
and lets stop here, there have been numerous discussions if the dsd+ source should be released or not, lets not have another one

 

[yo4tnv]

After a long-time compiling (intel atom /2g ram eeepc) , it works ! I see a rectangular signal on 394Mhz but no data flows on tetra monitor. Maype i didn`t set the right freq and ppm. How can I finetune the freq in the live receiver? is there anyway to do that but changing center freq on grc flowgraph ?

Thanx Jacek, 73!

 

[yo4tnv]

First tryout it worked, after reboot I`ve got glitches..

~/Downloads/TETRA/osmo-tetra-sq5bpf/src$ ./receiver1 1
Traceback (most recent call last):
File "demod/python/simdemod2.py", line 18, in <module>
import osmosdr
File "/usr/local/lib/python2.7/dist-packages/osmosdr/__init__.py", line 45, in <module>
from osmosdr_swig import *
File "/usr/local/lib/python2.7/dist-packages/osmosdr/osmosdr_swig.py", line 28, in <module>
_osmosdr_swig = swig_import_helper()
File "/usr/local/lib/python2.7/dist-packages/osmosdr/osmosdr_swig.py", line 24, in swig_import_helper
_mod = imp.load_module('_osmosdr_swig', fp, pathname, description)
ImportError: /usr/local/lib/libgnuradio-osmosdr-0.0.3git.so.0.0.0: undefined symbol: bladerf_set_correction

Any idea?

Thanks!

 

[sq5bpf]

After a long-time compiling (intel atom /2g ram eeepc) , it works ! I see a rectangular signal on 394Mhz but no data flows on tetra monitor. Maype i didn`t set the right freq and ppm. How can I finetune the freq in the live receiver? is there anyway to do that but changing center freq on grc flowgraph ?

you have boxes to enter frequency and offset (for example for 2MHz sample rate you could have +-1MHz offset, try to avoid 0 offset, so for example 393.5MHz freq and 500kHz offset will give you 394MHz). after entering the frequency press Enter, there is a label RX1 which will show the current frequency

then you have a slider to adjust ppm (use your mouse or keyboard arrows), you can use a different program to find out the ppm (the sign can differ in other programs, so you might have -56ppm in one and 56ppm in another). for finetuning you have a slider labelled Fine1, where you can tune +-5kHz.

the spectrum should be symmetrical to 0kHz and be about 13kHz wide.

also this might not be a tetra signal, or maybe it is too weak, or has some interfearing signal nearby

 

[sq5bpf]

First tryout it worked, after reboot I`ve got glitches..
[...]
ImportError: /usr/local/lib/libgnuradio-osmosdr-0.0.3git.so.0.0.0: undefined symbol: bladerf_set_correction

i'm not sure what is the problem, but try this:
as root add /usr/local/lib to /etc/ld.so.conf (or one of the files in /etc/ld.so.conf.d , whichever you like) and run ldconfig

 

[yo4tnv]

i'm not sure what is the problem, but try this:
as root add /usr/local/lib to /etc/ld.so.conf (or one of the files in /etc/ld.so.conf.d , whichever you like) and run ldconfig

Doesn`t solve it . More than that, now even GRC won`t start, throwing warnings and errors.
I definetely messed it up somewhere. I`ll try again from 0 on my home desktop (amd a6 apu quad-core - 4g ram) which is way faster than the poor atom.

 

[sq5bpf]

Doesn`t solve it . More than that, now even GRC won`t start, throwing warnings and errors.
I definetely messed it up somewhere. I`ll try again from 0 on my home desktop (amd a6 apu quad-core - 4g ram) which is way faster than the poor atom.

maybe you tried to compile it again with different flags, or you installed some additional packages (like compiled gnuradio, and then installed gnuradio packages from the distribution repository)

btw the desktop is a good choice, you should have enough cpu to process many channels at once

 

[yo4tnv]

IQ recordings (SDRsharp 16 and 32bit float, 2.4Msps) here Index of /y/yo4tnv//RAWIQ Note the 5 (five) clear and powerfull continous signals here http://www.qsl.net/yo4tnv/RAWIQ/SDRSharp_20141129_141827Z_393081kHz_IQ.wav

 

[yo4tnv]

SDR# TETRA signals screencapture

screencapture