Thanks for the response. I am using the GRC and I let the preamble size=0. When I use a lower number of occupied tones this error doesn't occur. However if I used the values specified in the first post that message appears
Michael Dickens-3 wrote: > > Hi Francisco - The code in question is, as the error says, at line 106 of > the Python file "ofdm.py": > > self.preambles = digital_swig.ofdm_insert_preamble(self._fft_length, > padded_preambles) > > This code calls the C++ code found in the file > digital_ofdm_insert_preamble.cc, which throws an error when any valid > preamble's length is not equal to the FFT size. This throwing has nothing > to do with the cyclic prefix length or # occupied tones. You should be > able set no preambles, according to the code, by sending in a zero-length > vector (I think). The preamble must be a vector of vectors, with the > first dimension being the number of preambles and the second dimension > must be the FFT length. Check out which preamble you're using would be my > recommended next step. Good luck. - MLD > > On Jul 11, 2012, at 2:54 PM, frankist wrote: >> I was trying to use the OFDM Mod block to create a OFDM signal with FFT >> size=8192, occupied tones=6818 and CP=2048 >> >> However I keep getting this error: >> >> File "/usr/local/lib/python2.7/dist-packages/gnuradio/digital/ofdm.py", >> line 106, in __init__ >> padded_preambles) >> File >> "/usr/local/lib/python2.7/dist-packages/gnuradio/digital/digital_swig.py", >> line 4517, in ofdm_insert_preamble >> return _digital_swig.ofdm_insert_preamble(*args, **kwargs) >> RuntimeError: digital_ofdm_insert_preamble: invalid length for preamble >> symbol >> >> If I use a lower number of occupied tones this error disappears but I was >> interested in this number because it is close to the DVB-T 8k mode. >> >> Can you explain me what am I doing wrong or if there is a workaround for >> this problem > > > _______________________________________________ > 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-OFDM-Mod-block-tp34147481p34166579.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
