# SOCIS project update 2

**URL:** <https://www.ruby-forum.com/t/socis-project-update-2/242294>\
**Category:** GNU Radio\
**Created:** [June 12, 2015, 6:39pm UTC](https://www.ruby-forum.com/t/socis-project-update-2/242294 "2015-06-12T18:39:56Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![musicdenotation](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/m/ea666f/32.png) [@musicdenotation](https://www.ruby-forum.com/u/musicdenotation)\
**Post date:** [June 12, 2015, 6:39pm UTC](https://www.ruby-forum.com/t/socis-project-update-2/242294/1 "2015-06-12T18:39:56Z")

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Hey GNU Radio’ers!

Another week has passed. Thus, it’s time for my next project update.  
The week started with a fairly good event. I found a bug in the  
decoder which led to incorrect results.  
I studied various papers and algorithms for decoding performance  
improvements. Especially Successive Cancellation List Decoding SCLD  
caught my attention. Also, papers exist which describe vector  
optimization for x86 CPUs and SIMD utilization. I will get back to  
this once I’m working on VOLK optimization later in the project.  
In order to have meaningful codes available, I started working on some  
channel construction code. First of all, BEC channels can be  
calculated efficiently, but I don’t consider them to be interesting  
for GNU Radio. Let me know if you have a different opinion on this.  
And why. I consider BSC as the most interesting case.  
There exist algorithms which approximate Z-parameters or channel  
capacities quite well. Also, Monte-Carlo simulations yield usable  
results. I’ll stick with them for now and will work on more  
sophisticated algorithms later. Just as outlined in my timeline.

Next week will bring some C++ coding. Encoders and decoders are  
waiting to be implemented in C++ for FECAPI.

More info and current project progress can be found in [1] and [2].

Cheers  
Johannes

[1] [GitHub - jdemel/gnuradio: GNU Radio](https://github.com/jdemel/gnuradio)  
[2] [GitHub - jdemel/socis-2015-gr-results: ESA SOCIS 2015 files and information](https://github.com/jdemel/socis-proposal)

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**Author:** ![jdejong](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/j/a9a28c/32.png) [@jdejong](https://www.ruby-forum.com/u/jdejong)\
**Post date:** [June 12, 2015, 6:52pm UTC](https://www.ruby-forum.com/t/socis-project-update-2/242294/2 "2015-06-12T18:52:13Z")

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On 12.06.2015 09:36, Johannes D. wrote:

> channel construction code. First of all, BEC channels can be  
> calculated efficiently, but I don’t consider them to be interesting  
> for GNU Radio. Let me know if you have a different opinion on this.  
> And why. I consider BSC as the most interesting case.

Hey Johannes,

in the since-abandoned channel-coding toolbox that was once started at  
CEL, there are blocks for BSC as well as channels based on Markov-chains  
(e.g. for burst errors within BSCs). Both would be interesting to GNU  
Radio, and you could simply port those into GNU Radio. IIRC, I wrote  
both those blocks myself, so there would be no copyright issue here, and  
might save you some work.

Cheers,  
Martin