FEC and small FFT functions
AFF3CT : (all FECs)
https://aff3ct.github.io/fec_libraries.html
Radford Neal (LDPC in C) :
http://radfordneal.github.io/LDPC-codes/index.html
IT++ (LDPC)
https://itpp.sourceforge.net/4.3.1/tutorial.html
CML (LDPC, Turbo, Matlab/C)
http://www.iterativesolutions.com/index.html
(LDPC, 收费)
https://www.ldpc-decoder.com/
Rob Maunder (法研的版本)
https://github.com/robmaunder
GIT上的列表
https://github.com/cihatkececi/ChannelCodingProjectList
Small FFT Program
https://www.nayuki.io/page/free-small-fft-in-multiple-languages
https://www.guitarscience.net/papers/dffts.c