Dear Marcus, I truly appreciate your prompt reply. However, I am not sure what should I put in the 'modulus' field of the block. By hit and trial, wrong outputs are emerging. Please guide.
Best Regards, Huzaifa Marcus D. Leech wrote: > >> We just removed the throttle blocks and the same problem remains. Please >> let >> us know how to achieve symbol synchronization. >> >> > Well, you're using DPSK, but not using a differential encoder on the TX > side, nor a differential decoder on the RX side. > >> 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 >>>>> [email protected] >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>> >>>> _______________________________________________ >>>> Discuss-gnuradio mailing list >>>> [email protected] >>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>> >>>> > > > -- > Marcus Leech > Principal Investigator > Shirleys Bay Radio Astronomy Consortium > http://www.sbrac.org > > > > _______________________________________________ > Discuss-gnuradio mailing list > [email protected] > https://lists.gnu.org/mailman/listinfo/discuss-gnuradio > > -- View this message in context: http://old.nabble.com/Problem-with-USRP%21-tp33653047p33653178.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list [email protected] https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
