The delay before the decoder might be throwing off the alignment at the output. Might consider setting to 0 or removing.
Generally If you use a test input vector like the block of 0xff and 0x00 I mentioned before, you should be able to look at the relative delay between input and output by putting the source output and decoder output into a time sink and measuring the delay between the source signal being non 0 and the decoder output being non 0. Jared. On Wed, Aug 23, 2023, 4:58 AM Jiya Johnson <jiyajohnso...@gmail.com> wrote: > I am getting constant BER through our the SNR ranges > > > > > On Tue, Aug 22, 2023, 7:15 PM Jiya Johnson <jiyajohnso...@gmail.com> > wrote: > >> Ok, I will check. >> I was confused with this stack input ( >> https://stackoverflow.com/questions/54946638/punctured-convolutional-codes-in-gnu-radio >> ) >> I will try with 1011 and delay blocks and will update you. >> >> On Tue, Aug 22, 2023, 7:12 PM U L <jaredd...@gmail.com> wrote: >> >>> The extended en/decoder does puncturing and zero stuffing internally so >>> you don't need an extra puncturing block. Like I mentioned, the puncturing >>> string can only have 0s and 1s so 13 is invalid. I'd try '1011' instead. >>> >>> Finally I think you still need some delay between your source and the >>> ber block to align your input bytes with those from your output. The output >>> does not start with the first decoded bit, but some number of 0s. In one of >>> your prior flowgraphs you did have a delay. What happened to it? >>> >>> Jared. >>> >>> >>> On Tue, Aug 22, 2023, 4:13 AM Jiya Johnson <jiyajohnso...@gmail.com> >>> wrote: >>> >>>> Hi Jared, >>>> Completed the flowgraph based on the inputs from you like i have >>>> taken code rate :2/3 and pattern 1101(0xD)-puncture size-4 as reference >>>> from ( >>>> https://stackoverflow.com/questions/54946638/punctured-convolutional-codes-in-gnu-radio) >>>> bt still i am facing the issue.Always i am getting 10^-0.3 BER FROM 0 to 15 >>>> dB. >>>> >>>> [image: Screenshot from 2023-08-22 15-41-43.png] >>>> >>>>
