Gnuradio/gr-digital/python/digital/ofdm_receiver.py

GNU Radio
1

Hi all:
Thank you in advance.
Version of gnuradio:3.7.4
I have read the
gnuradio/gr-digital/python/digital/ofdm_receiver.py,and i see:
self.connect(self, self.chan_filt)

filter the input channel

    self.connect(self.chan_filt, self.ofdm_sync)                  #

into the synchronization alg.
self.connect((self.ofdm_sync,0), self.nco, (self.sigmix,1)) #
use sync freq. offset output to derotate input signal
self.connect(self.chan_filt, (self.sigmix,0)) #
signal to be derotated
self.connect(self.sigmix, (self.sampler,0)) #
sample off timing signal detected in sync alg
self.connect((self.ofdm_sync,1), (self.sampler,1)) #
timing signal to sample at

    self.connect((self.sampler,0), self.fft_demod)                #

send derotated sampled signal to FFT
self.connect(self.fft_demod, (self.ofdm_frame_acq,0)) #
find frame start and equalize signal
self.connect((self.sampler,1), (self.ofdm_frame_acq,1)) #
send timing signal to signal frame start
self.connect((self.ofdm_frame_acq,0), (self,0)) #
finished with fine/coarse freq correction,
self.connect((self.ofdm_frame_acq,1), (self,1)) #
frame and symbol timing, and equalization

    But i have read the

gnuradio/gr-digital/examples/ofdm/rx_ofdm.grc.And i think the connection
way of the code in gnuradio/gr-digital/python/digital/ofdm_receiver.py
is different with the connection way in rx_ofdm.grc.Can someone explain
to me?I’m so puzzled.Thanks so much.
Best regards

2

On 05.06.2014 15:26, xianda wrote:

     But i have read the

gnuradio/gr-digital/examples/ofdm/rx_ofdm.grc.And i think the connection
way of the code in gnuradio/gr-digital/python/digital/ofdm_receiver.py
is different with the connection way in rx_ofdm.grc.Can someone explain
to me?I’m so puzzled.Thanks so much.
Best regards

This is an old script, which uses different blocks. It has nothing to do
with the OFDM code used in rx_ofdm.grc. Just ignore this.

M

3

Hi:
Thank you for your kindly reply.Thank you for providing your ofdm
code.These help me a lot.
1.(gnuradio/gr-digital/examples/ofdm/(benchmark_rx.py and so
on))These code belonging to the new version or old version ?
2.In my opinion,all the code related to the new version ofdm are
save in gnuradio/gr-digital/lib and gnuradio/gr-digital/include.Is it
right?But no python code related to the new version of ofdm?
3.I’m now working on the ofdm.But in the catalogue
gnuradio/gr-digital,there are so many old and new ofdm code mixed.Can
you tell me which is the new code?
Thanks very much.
Best regards,
xianda

4

On 05.06.2014 16:42, xianda wrote:

Hi:
Thank you for your kindly reply.Thank you for providing your
ofdm code.These help me a lot.
1.(gnuradio/gr-digital/examples/ofdm/(benchmark_rx.py and so
on))These code belonging to the new version or old version ?

Old.

    2.In my opinion,all the code related to the new version ofdm are

save in gnuradio/gr-digital/lib and gnuradio/gr-digital/include.Is it
right?But no python code related to the new version of ofdm?

ofdm_txrx.py is new. But not as much Python as the old code, and that’s
a feature.

   3.I'm now working on the ofdm.But in the catalogue

gnuradio/gr-digital,there are so many old and new ofdm code mixed.Can
you tell me which is the new code?

Anything referenced in ofdm_txrx.py is new. Rest is old.

M