Hi Luke, I've found using the FFT blocks are the most cpu efficient way to extract a channel from the whole 20MHz of the HackRF. Have a look at my latest Scanoo release built in GRC which uses the 'Keep X in N' block to select the channel required. There's also a spectrum sense mode which locks on to the strongest signal within the 20MHz bandwidth if it is not in the blocked frequency list:
https://github.com/m0mik/scanoo Cheers, Mike -- Mike Jameson M0MIK BSc MIET Email: m...@scanoo.com Web: http://scanoo.com On Wed, Aug 21, 2013 at 7:15 PM, Luke B <luk...@gmail.com> wrote: > I am working on a processing multiple signals using a single source block. > The background is below, but I had a couple of high level questions: > > - What is the best approach performance wise for selecting multiple > ~15khz channels from a 2mhz+ source block? Is it using a Xlating FIR > Filter with a low-pass? Is it more efficient to use a SIN Sig source & > Multiply Block with a low-pass FIR Filter? Is there a better way to extract > a filter? > > - What is the best way to have different bunch of blocks processing each > signal run independently and not block each other? I want to do this as a > GR C++ program is there any way to run the signal source and chanelizersas > one thread and then have the different processing chains run as separate > threads? Is there a way to put a queue or buffer inbetween blocks that > would allow for a chain of blocks to be separated between threads? > > Or am I better off doing the basic signal/channel processing for > everything in a single process and then writing the results to a file and > then having a process which goes through the files and does the more > intensive vocoder work in non-real time? > > Any pointers or examples of how to do threading with GR C++ code would be > really helpful. I am not sure of the best architectual approach. > > > Background: > I have taken the gr-smartnet code and done a skeleton implementation in > C++. I want to process the digital trunking channel and then decode and > record the digital audio from all of the different talk groups. Since it is > trunked, channels will be randomly be turning on and off and talk groups > will be switching from channels. It would be good to have a separate thread > for the trunk decoding and the separate digital audio recorders. Ideally, I > would like to be able to do this over 8 or 10Mhz using my HackRF. > > My code, which is working enough to decode the trunking channel, is here: > https://github.com/robotastic/sdr > > Thanks! > > - Luke > > _______________________________________________ > 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
