Hello Everyone,

I’m Manu, one of the GSoC student under GNU Radio this year. I worked on

LDPC Codes, mentored by Jens. Another GSoC student Tracie also worked on

LDPC Codes this summer. We both worked such that there is minimum

duplicates and both our work complemented each other.

As the final output I have an Out Of Tree module gr-ldpc which

implements a

generic decoder and a generic encoder for LDPC codes. The encoder block

expects an LDPC code specified in alist[1] format. There are two decoder

blocks, one for Binary Symmetric Channel model and another for AWGN

Channel

model. The decoder implements the sum product algorithm[2]. Also two

algorithms for construction of LDPC codes have been implemented. I

prepared

a video presentation of my work to be presented at GR Con 2013, and the

presentation is available at

http://home.iitb.ac.in/~manu.ts/presentation.pdf (presentation) and

http://home.iitb.ac.in/~manu.ts/presentation.ogv (video). The gr-ldpc

OOT

module is available at https://github.com/manuts/gr-ldpc. During the

project we also worked on porting the codes to fecapi, which is a

wonderful

framework for developing FEC blocks. I’m yet to finish porting gr-ldpc

to

FECAPI framework.

Overall, GSoC 2013 was a great experience. Frankly, I was not able to

meet

all the goals set in my proposal. I hope to fulfill all that I promised

in

the future. The encoder/decoder blocks have to be optimized. And in

future

I intend to bring more of Coding techniques into fecapi framework.

There is lot many people to whom I’m thankful for this wonderful

experience. I don’t pick any name just so that the mail is concise as

possible. I also thank the entire GNU Radio community for this

opportunity.

Hoping for the feedbacks on the module,

–

Manu T S

[1] http://www.inference.phy.cam.ac.uk/mackay/codes/alist.html

[2] http://www.cs.toronto.edu/~radford/ftp/LDPC-2012-02-11/decoding.html