Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
I know this is going back a bit but I would like to do the same thing for my Gnuradio satellite ground station. I was actually tempted to compile satellite tracking into a Gnuradio block. One you could simply use in a flowchart without any of the messing about with XMLRPC but like my new hexagonal wheel project, with active compensatory suspension, it might be better to use what's already there. Did anyone do this? And, how difficult would it be in practice to develop a native block that either contains predict, or accesses it? Possibly not very difficult at all and maybe already done? Mike _ On 22/07/13 12:31, M Dammer wrote: Is it possible to link Gnuradio and Gpredict ? I want to use Gpredict as tracker controlling the antenna position and to pass doppler corrected frequency data to Gnuradio. In a word, yes. Can be very simple. I did it by using an XML Server in the flow graph, and wrote a quick XML client (actually I stole most of it from an example), and sent the doppler info from predict via a variable. doppler info was received from predict using some code to query predict using UDP. I think I just used nc to send the UDP query to predict, recovered the shift from the reply, and sent it back to the XML Server running within the flow graph. Unfortunately I can't find my actual code right now, but I literally copied an example, and added the UDP Predict clients bit. It went something like this pseudo code (Yes, this is a mix of shell,and python, and you need to re-write the getting doppler from predict yourself, but you get the idea, and should give you enough) import time import sys from socket import * import xmlrpclib import binascii s = xmlrpclib.Server(http://192.168.39.74:8081 http://192.168.39.74:8081%22 ;) infinite=1 while infinite == 1; # Grab predict doppler using UDP DOPPLER=`nc -u -s 2 $PREDICTHOST GET_DOPPLER $NORAD_NUMBER` s.set_doppler_shift($DOPPLER) time.sleep(1) The variable (lets call it doppler_shift) exists in the flowgraph, and was multiplied appropriately and applied to the centre frequency of a FIR filter. You can pretty much pass any information you want in and out of a flow graph using a XML Server/Client pair. I've done TX/RX switching, and am currently working on telemetry decoding/display Iain ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
I just found a good starting point. This program uses hamlib, a library that is often used to control rigs and antenna rotors and that is supported by GPredict: http://james.ahlstrom.name/hamlib.html I just tested it and GPredict connects well to localhost:4575. The server programs output shows the proper doppler corrected frequencies etc. As it is python it can probably converted into a GRC block. 73 Mark On 28/03/14 14:47, rajesh kd wrote: Hi, Can you explain in detail regarding querying the Gpredict for doppler corrected freq. using UDP, since I novice to UDP. If possible,, can you please post the relevant code. Rajesh -- View this message in context: http://gnuradio.4.n7.nabble.com/linking-Gnuradio-and-Gpredict-tp42620p47286.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
Hi, Can you explain in detail regarding querying the Gpredict for doppler corrected freq. using UDP, since I novice to UDP. If possible,, can you please post the relevant code. Rajesh -- View this message in context: http://gnuradio.4.n7.nabble.com/linking-Gnuradio-and-Gpredict-tp42620p47286.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
If all you need is something in python you can just use pyephem http://rhodesmill.org/pyephem/ Alex On Fri, Mar 28, 2014 at 6:33 PM, M Dammer i...@mdammer.net wrote: I just found a good starting point. This program uses hamlib, a library that is often used to control rigs and antenna rotors and that is supported by GPredict: http://james.ahlstrom.name/hamlib.html I just tested it and GPredict connects well to localhost:4575. The server programs output shows the proper doppler corrected frequencies etc. As it is python it can probably converted into a GRC block. 73 Mark On 28/03/14 14:47, rajesh kd wrote: Hi, Can you explain in detail regarding querying the Gpredict for doppler corrected freq. using UDP, since I novice to UDP. If possible,, can you please post the relevant code. Rajesh -- View this message in context: http://gnuradio.4.n7.nabble.com/linking-Gnuradio-and-Gpredict-tp42620p47286.html Sent from the GnuRadio mailing list archive at Nabble.com. ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] linking Gnuradio and Gpredict ?
Is it possible to link Gnuradio and Gpredict ? I want to use Gpredict as tracker controlling the antenna position and to pass doppler corrected frequency data to Gnuradio. Does any interface to Gpredict (or hamlib) exist ? thanks for any hints, Mark ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
Hi, Gpredict is based on predict, which has several interfaces for Doppler prediction. Not sure if Gpredict inherited these interfaces. Yours Martin Am 22.07.2013 13:31, schrieb M Dammer: Is it possible to link Gnuradio and Gpredict ? I want to use Gpredict as tracker controlling the antenna position and to pass doppler corrected frequency data to Gnuradio. Does any interface to Gpredict (or hamlib) exist ? thanks for any hints, Mark ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] linking Gnuradio and Gpredict ?
On 22/07/13 12:31, M Dammer wrote: Is it possible to link Gnuradio and Gpredict ? I want to use Gpredict as tracker controlling the antenna position and to pass doppler corrected frequency data to Gnuradio. In a word, yes. Can be very simple. I did it by using an XML Server in the flow graph, and wrote a quick XML client (actually I stole most of it from an example), and sent the doppler info from predict via a variable. doppler info was received from predict using some code to query predict using UDP. I think I just used nc to send the UDP query to predict, recovered the shift from the reply, and sent it back to the XML Server running within the flow graph. Unfortunately I can't find my actual code right now, but I literally copied an example, and added the UDP Predict clients bit. It went something like this pseudo code (Yes, this is a mix of shell,and python, and you need to re-write the getting doppler from predict yourself, but you get the idea, and should give you enough) import time import sys from socket import * import xmlrpclib import binascii s = xmlrpclib.Server(http://192.168.39.74:8081;) infinite=1 while infinite == 1; # Grab predict doppler using UDP DOPPLER=`nc -u -s 2 $PREDICTHOST GET_DOPPLER $NORAD_NUMBER` s.set_doppler_shift($DOPPLER) time.sleep(1) The variable (lets call it doppler_shift) exists in the flowgraph, and was multiplied appropriately and applied to the centre frequency of a FIR filter. You can pretty much pass any information you want in and out of a flow graph using a XML Server/Client pair. I've done TX/RX switching, and am currently working on telemetry decoding/display Iain ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
