We just removed the throttle blocks and the same problem remains. Please let us know how to achieve symbol synchronization.
huzaifazafar108 wrote: > > Dear John, > > Thank you for such a prompt reply. Okay, we will remove the throttle > blocks just now. But can you guide us how to achieve symbol > synchronization then? > > Best Regards, > Huzaifa > > > > John Malsbury wrote: >> >> You do not need to use throttles when using a UHD sink/source, because >> the device provides timing for the flowgraph. >> >> Remove the throttles and try again. If you still see the failure I'd >> say you are not achieving symbol sync. >> >> -John >> >> >> >> On 04/08/2012 01:58 PM, Huzaifa Zafar wrote: >>> Dear all, >>> >>> I am working with 3 people on a project involving GNU Radio and USRP1. >>> We have tried to implement a simple point to point digital >>> communication system in GRC involving DQPSK modulation. Using a vector >>> source we are sending a finite stream of zeros and ones (the vector >>> source has Repeat set to yes). On the receiver side, what we receive >>> is really very strange: The same stream of zeros and ones, but with >>> extra zeros in between our actual data. For example, we send three >>> ones and three zeros, but what we receive is a one followed by seven >>> zeros, another one followed by seven zeros, another one followed by >>> seven zeros, and then a zero followed by seven zeros e.t.c. We tried >>> to experiment more by using the 'KEEP 1 in N' block and the >>> 'DECIMATING FIR FILTER', but things are not working out the way they >>> should. >>> >>> I am also attaching a snapshot of the .grc file for your reference. >>> Please tell us the reason why these extra zeros are present between >>> our data bits, and the way to combat this effect (remember that the >>> decimating fir filter and keep 1 in N block are not showing the >>> desired output). Any kind of help is appreciated in advance. >>> >>> -- >>> Huzaifa Zafar >>> >>> >>> _______________________________________________ >>> 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 >> >> > -- View this message in context: http://old.nabble.com/Problem-with-USRP%21-tp33653047p33653150.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
