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Decodes LDPC code based on the standard message-passing schedule, which is a version of the flooding schedule. According to the flooding schedule, all the symbol nodes, and subsequently all the check nodes, pass new messages to their neighbors in each iteration.

The message that is sent from message node (v) to the check node (c) must not take into account the message sent in the previous iteration from c to v. The same is true for messages passed from check nodes to message nodes.


parity check matrix

The sparse parity check matrix generated by MT LDPC Generate Regular Parity Check Matrix or MT LDPC Generate Irregular Parity Check Matrix. You can also set a parity check matrix that is not rank deficient in this parameter.



The likelihoods of the received symbols.


maximum number of iterations

The maximum number of iterations for the iterative decoding process. The decoder stops iterating after the number of iterations exceeds the value of the maximum number of iterations or if the decoder satisfies other conditions.

Default: 100


error in

Error conditions that occur before this node runs. The node responds to this input according to standard error behavior.

Default: no error



A Boolean that determines whether the internal state of the decoder is cleared.

TRUE Clears any buffered bits from previous iterations.
FALSE Continues decoding from the previous iteration. Any buffered bits from the previous iteration are added to the beginning of the input bit stream prior to decoding.

Default: TRUE


output bit stream

Bit sequence decoded by this node.


error out

Error information. The node produces this output according to standard error behavior.