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This a framework to test new ideas in transmission technology. Actual development is a LDPC-coder in

ldpc_soft
=========


This LDPC-decoder is written to take successive symbols from
two input-streams with two independant SNRs. Additionaly,
the output of the decoder doesn't have a hard-decision, so that
it's most suited to fit into a successive interference cancellation
environment.


ldpc_decode_soft
----------------

LDPC-decoder-MIMO

Successive Interference cancellation is effected by the change in variance
for every 'outer loop' iteration. The variance is sum of the variance of 
thermal noise and the variance of other user(interferer).

The variance is collected from 'sic' module.

snr1 = H1'H1/var(interference)+var(noise1)
snr2 = H2'H2/var(interference)+var(noise2)

Inputs:
	SYMBOL_COMPLEX

outputs:
	DOUBLE_COMPLEX

Config:
	iterations<int>: 30
		How many iterations are done in this module

	ldpc_code_id<int>: 1
		The code for the ldcp. Only 1 is working, as it's the
		only one that is a multiple of 8

	sic<int>: -1
		Block-id of the SIC block. This will provide snr1, snr2.


Stats:
	dnodes<int>:
		How many data-bits

	var_xhat_1<double>:
		The variation on antenna 1

	var_xhat_2<double>:
		The variation on antenna 2


ldpc_encode
-----------

This is the standard LDPC-encoder from Bernhard Bruhn.

Inputs:
	U8

outputs:
	U8

Config:
	ldpc_code_id<int>: 1
		The index of the ldpc-code. For the moment, three codes
		are implemented:
		1 - rate .25, size 4000
		2 - rate .5, size 3992
		3 - rate .75, size 3992