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Encoder parameters

--enc-cw-size, -N

Type

integer

Examples

--enc-cw-size 1024

Note

This parameter value is automatically deduced if the H parity matrix is given with the dec-ldpc-dec-h-path parameter or if the G generator matrix is given with the enc-ldpc-enc-g-path parameter.

--enc-info-bits, -K

Type

integer

Examples

--enc-info-bits 512

Note

This parameter value is automatically deduced if the G generator matrix is given with the enc-ldpc-enc-g-path parameter.

Note

In some cases, this parameter value can be automatically deduced if the H parity matrix is given with the dec-ldpc-dec-h-path parameter. For regular matrices, K = N − M where N and M are the H parity matrix dimensions. For non-regular matrices, K has to be given.

--enc-type

Type

text

Allowed values

LDPC LDPC_H LDPC_DVBS2 LDPC_IRA LDPC_QC AZCW COSET USER

Default

AZCW

Examples

--enc-type AZCW

Description of the allowed values:

Value Description
LDPC Select the generic encoder that encode from a given G generator matrix (to use with the enc-ldpc-enc-g-path parameter).
LDPC_H Build the G generator matrix from the given H parity matrix and then encode with the LDPC method (to use with the dec-ldpc-dec-h-path parameter).
LDPC_DVBS2 Select the optimized encoding process for the H matrices (to use with the enc-ldpc-enc-cw-size and enc-ldpc-enc-info-bits parameters).
LDPC_IRA Select the optimized encoding process for the H parity matrices (to use with the dec-ldpc-dec-h-path parameter).
LDPC_QC Select the optimized encoding process for the H parity matrices (to use with the dec-ldpc-dec-h-path parameter).
AZCW See the common enc-common-enc-type parameter.
COSET See the common enc-common-enc-type parameter.
USER See the common enc-common-enc-type parameter.

Note

The LDPC_DVBS2 encoder type allow the simulation of the standard but without the code. All matrices described by the standard (Tables 5a/5b page 22-23) are available. You just need to give to the arguments enc-ldpc-enc-info-bits and enc-ldpc-enc-cw-size the real K and N dimensions, respectively.

--enc-g-path

Type

file

Rights

read only

Examples

--enc-g-path example/path/to/the/G_matrix.alist

--enc-g-method

Type

text

Allowed values

IDENTITY LU_DEC

Default

IDENTITY

Examples

--enc-g-method IDENTITY

Description of the allowed values:

Value Description
IDENTITY Generate an identity on H to get the parity part.
LU_DEC Generate a hollow G thanks to the LU decomposition with a guarantee to have the systematic identity. Do not work with irregular matrices.

LU_DEC method is faster than IDENTITY.

--enc-g-save-path

Type

file

Rights

write only

Examples

--enc-g-save-path example/path/to/the/generated/G_matrix.alist

Hint

When running the LDPC_H encoder, the generation of the G matrix can take a non-negligible part of the simulation time. With this option the G matrix can be saved once for all and used in the standard LDPC decoder after.