readme

软件无线电的平台

ldpc_siso_ics
=============


 LDPC codes are Low Density Parity Check codes used in favor of
convolutional codes. They are quite experimental and not widely
tested. Furthermore this module is not optimsed at all!
 This has been adapted a bit to the ICS-cards


ldpc_decode_siso_ics
--------------------

 Tries to decode the received slot. As it is really slow to do this,
this module should be SUBS_MSG_THREADed so that it has more than one
slot's time to decode.

Inputs:
	SYMBOL_COMPLEX

outputs:
	U8

Config:
	chest<int>: -1
		Define the matched filter to calculate the correct a/variance

	drop_blocks<int>: 0
		How many blocks to drop

	iterations<int>: 30
		The number of iterations that are done to decode the message.
		Each iteration contains a cnode->vnode->cnode cycle

	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


Stats:
	snr<double>:
		The calculated SNR in case of a AWGN channel


ldpc_encode_siso_ics
--------------------

 Encodes a slot. Needs to have a modulator-module with a QPSK
modulation.

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