Re: FEC in gnruadio

GNU Radio
1

implementation of the gr-fec so that I can go through the c++

We’re also about to merge in another approach to LDPC encoding and decoding
What’s your particular interest in FEC? Are you looking to use it or
implement other codes not already in gr-fec? For the FEC API itself, there
is no other reference than the manual page and a presentation from the
original author at our GRCons:

GRCon14 - Presentations — Rondeau Research
GRCon2013 - Presentations — Rondeau Research

Tom

Hi Tom,

Thanks for the links. I am targeting Turbo Codes mainly for short frame
size. I found one presentation on turbo codes

http://gnuradio.squarespace.com/storage/grcon14/presentations/Sep18_02_Karra_TurboCodes.pdf

but I could not find its source code in gnuradio. Are Turbo codes
implemented in gnuradio? if yes, in which version can I find it? One
more
question, I am targeting short frame length burst, currently which FEC
in
gnuradio can give me best gain in this case?

2

On Tue, Jun 16, 2015 at 1:03 PM, bob wole [email protected] wrote:

the
Have a look at the manual. The API itself is quite well described I think:

Johannes D. is working on polar codes this summer.

implemented in gnuradio? if yes, in which version can I find it? One more
question, I am targeting short frame length burst, currently which FEC in
gnuradio can give me best gain in this case?

–
Bob

Bob,

Yes, Kiran’s TPC work has been integrated as of 3.7.7.1. (I even pointed
out the links to the manual pages for the tpc_encoder and tpc_decoder
above.)

Tom

3

On Tue, Jun 16, 2015 at 11:41 PM, Tom R. [email protected] wrote:

through the c++ implementation more productively and add
gr-fec. I
Hi Bob,
GNU Radio Manual and C++ API Reference: gr::fec::tpc_decoder Class Reference
GRCon2013 - Presentations — Rondeau Research
GRCon14 - Presentations — Rondeau Research

Bob,

Yes, Kiran’s TPC work has been integrated as of 3.7.7.1. (I even pointed
out the links to the manual pages for the tpc_encoder and tpc_decoder
above.)

Tom

Thanks Tom,

I am going to test them soon for my bursty system :slight_smile: Lets see how it
works.

4

On Tue, Jun 30, 2015 at 2:00 PM, bob wole [email protected] wrote:

implementation of the gr-fec so that I can go through the c++
think:

Johannes D. is working on polar codes this summer.
Tom
but I could not find its source code in gnuradio. Are Turbo codes
Yes, Kiran’s TPC work has been integrated as of 3.7.7.1. (I even pointed

in gnuradio/gr-fec/examples/
fec.extended_encoder(encoder_obj_list=enc, threading=‘capillary’,

File “/usr/local/lib/python2.7/dist-packages/gnuradio/gr/top_block.py”,

fecapi_async_decoders.grc runs without any errors.

Any Ideas what could be wrong ?

–
Bob

Any comments on it ?

5

On Thu, Jul 2, 2015 at 8:10 PM, bob wole [email protected] wrote:

On Tue, Jun 16, 2015 at 11:41 PM, Tom R. [email protected] wrote:

followed during the implementation of the gr-fec so that I can go
I just stared working on FEC in gnuradio. I found that there is

GNU Radio Manual and C++ API Reference: gr::fec::tpc_encoder Class Reference
And the GSoC presentations:

Thanks Tom,
gnuradio version 3.7.7.1
File “/home/gnuradio/gr-fec/examples/ber_test.py”, line 267, in
File “/usr/local/lib/python2.7/dist-packages/gnuradio/fec/bitflip.py”,
Traceback (most recent call last):
RuntimeError: boost::thread_resource_error: Resource temporarily

Any comments on it ?

–
Bob

I hope somebody would reply on this.

6

On Tue, Jun 16, 2015 at 11:45 PM, bob wole [email protected] wrote:

–
It doesn’t cover the very recently added TPC and LDPC implementations.

there

Tom

Thanks Tom,

I am going to test them soon for my bursty system :slight_smile: Lets see how it works.

–
Bob

Hi list,

gnuradio version 3.7.7.1
ubunutu 14.04 32-bit

I am trying to use gr-fec and I am having issues running examples
located
in gnuradio/gr-fec/examples/

When I run ber_test.grc I get following error

Using Volk machine: avx_32_mmx_orc
Traceback (most recent call last):
File “/home/gnuradio/gr-fec/examples/ber_test.py”, line 267, in

tb = ber_test()
File “/home/gnuradio/gr-fec/examples/ber_test.py”, line 159, in
init
self.fec_extended_encoder_0 =
fec.extended_encoder(encoder_obj_list=enc, threading=‘capillary’,
puncpat=“puncpat”)
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/fec/extended_encoder.py”,
line 64, in init
self.blocks.append(fec.puncture_bb(len(puncpat),
read_bitlist(puncpat),
0))
File “/usr/local/lib/python2.7/dist-packages/gnuradio/fec/bitflip.py”,
line 47, in read_bitlist
if int(bitlist[i]) == 1:
ValueError: invalid literal for int() with base 10: ‘p’

Done (return code 1)

When I run tpc_ber_curve_gen.grc I get following error

Using Volk machine: avx_32_mmx_orc
Traceback (most recent call last):
File “/home/gnuradio/gr-fec/examples/tpc_ber_curve_gen.py”, line 450,
in

tb.start()
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/gr/top_block.py”,
line 106, in start
top_block_start_unlocked(self._impl, max_noutput_items)
File
“/usr/local/lib/python2.7/dist-packages/gnuradio/gr/runtime_swig.py”,
line
4860, in top_block_start_unlocked
return _runtime_swig.top_block_start_unlocked(*args, **kwargs)
RuntimeError: boost::thread_resource_error: Resource temporarily
unavailable

Done

fecapi_async_decoders.grc runs without any errors.

Any Ideas what could be wrong ?