Hi Amir, regarding the spectrum: Is your data white?
Best regards, Marcus On 10.08.20 21:40, Amir Hossein Aalipour wrote: > I could finally find the correct configuration. I just added a "pack k > bits" block between the "gmsk demod" and "correlate access code" blocks. I > found it while I was monitoring and comparing the input and output > waveforms of the mod and demod blocks. As was written in the gmsk demod > document, this block produces a stream of bits, one bit per byte and the > bit is written on the LSB of the corresponding byte. So I searched for a > block that extracts one bit from a byte and the result was "pack k bits" > which takes one bit from every input byte and puts the k bits that have > been taken, in a row beside each other. It worked! > > But when I saw the spectrum of the modulated signal, i.e the output of the > gmsk mod, it was not a well-known bell-shaped spectrum around zero Hz! It > was like the picture below. Why is it like that? > > Sorry for too many questions, can I also ask how to set the right sampling > rate of the USRP sink? I mean according to a flow graph like the below > transmitter, how can I calculate the sufficient sampling rate of the USRP > sink? Any hint is appreciated. > > Thank you very much. >
