On Thu, Mar 26, 2009 at 01:24:37PM -0400, satar...@eden.rutgers.edu wrote: > Hi, > > I am trying to run ALOHA MAC on gnu radio. The modulation scheme used is > GMSK. The Tx and Rx chains are as follows: > > Tx Chain: > > src -> framer -> crc enoder -> fec encoder -> preamble -> nrz -> > interpolator -> Gauus filter -> FM modulator -> gain -> usrp_tx > > Rx Chain > > usrp_rx -> filter -> demod -> integrator filter -> correlator -> fec > decoder -> crc decoder -> extract frame > > For some reason, I am unable to receive the frame when I run my python > scripts. I tested USRP boards by passing a simple sine-wave and it is > received correctly. I checked the output of usrp_tx on oscilloscope and it > does display the frame going through. To test, whether there was any > problem in the signalblocks I replaced usrp_tx by a filesink and dumped > the output of Tx chain in a file. I replaced the usrp_rx by this file and > the frame was correctly received. I think this means that there is problem > of configuration with usrp_tx and usrp_rx. Following are the configuration > scripts:
How are you doing symbol timing recovery on the receiver? Generating logging data using gr.file_sink's at varous points in the graph is often helpful in seeing what's going on. Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
