# Gnuradio/gr-digital/python/digital/ofdm\_receiver.py **URL:** \ **Category:** GNU Radio\ **Created:** [June 5, 2014, 3:28pm UTC](https://www.ruby-forum.com/t/gnuradio-gr-digital-python-digital-ofdm-receiver-py/230229 "2014-06-05T15:28:27Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![jason\_sam](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/7993a0/32.png) [@jason\_sam](https://www.ruby-forum.com/u/jason_sam)\ **Post date:** [June 5, 2014, 3:28pm UTC](https://www.ruby-forum.com/t/gnuradio-gr-digital-python-digital-ofdm-receiver-py/230229/1 "2014-06-05T15:28:27Z")
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 ---
**Author:** ![xianda](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/b38774/32.png) [@xianda](https://www.ruby-forum.com/u/xianda)\ **Post date:** [June 5, 2014, 4:23pm UTC](https://www.ruby-forum.com/t/gnuradio-gr-digital-python-digital-ofdm-receiver-py/230229/2 "2014-06-05T16:23:19Z")
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 ---
**Author:** ![xianda](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/b38774/32.png) [@xianda](https://www.ruby-forum.com/u/xianda)\ **Post date:** [June 5, 2014, 5:33pm UTC](https://www.ruby-forum.com/t/gnuradio-gr-digital-python-digital-ofdm-receiver-py/230229/3 "2014-06-05T17:33:34Z")
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 ---
**Author:** ![xianda](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/x/b38774/32.png) [@xianda](https://www.ruby-forum.com/u/xianda)\ **Post date:** [June 5, 2014, 6:33pm UTC](https://www.ruby-forum.com/t/gnuradio-gr-digital-python-digital-ofdm-receiver-py/230229/4 "2014-06-05T18:33:42Z")
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