Hi @all, on my long way to send multiple 802.11g frames i found another problem…
During the process the data is converted from frequency domain to time domain by inverse fft. The fft length is 64, and the input is the OFDM symbol with carrier tones (vector of 64 * gr_complex) The frame consists of 3 ofdm symbols and i want to convert two identical frames. So there are 6 elements with a size of 64* gr_complex. (6*64 *8Byte = 3072 Byte) When I compare the result of the first frame (Bytes 0 – 0x5FF) with the result of the second frame (0x600 – 0xBFF) in a hex editor the frames are NOT the same. They differ from each other, starting at Byte 0x800 to 0x200 in the fist frame. (0x800 = 2048dec!?) I’m able to reproduce the problem in GRC, using a file source –>throttle->inverse fft(size 64) -> file sink flowgraph., my input file is attached. Is there a problem with the precession of the ifft? (gnuradio 3.2.2, ubuntu 10.04) Has anybody an idea how to fix this? http://old.nabble.com/file/p31056403/input.dat input.dat http://old.nabble.com/file/p31056403/output.dat output.dat -Hans -- View this message in context: http://old.nabble.com/Problem-with-output-of-inverse-FFT-tp31056403p31056403.html Sent from the GnuRadio mailing list archive at Nabble.com. _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
