3.2.2. Source parameters

The source generates \(K\) information bits: it is the simulation starting point.

3.2.2.1. --src-info-bits, -K

Type

integer

Examples

--src-info-bits 64 -K 128

Select the number of information bits \(K\).

Warning

This argument is required only with the UNCODED simulation code type (cf. the --sim-cde-type, -C parameter).

3.2.2.2. --src-type

Type

text

Allowed values

AZCW RAND USER USER_BIN

Default

RAND

Examples

--src-type AZCW

Method used to generate the \(K\) information bits.

Description of the allowed values:

Value	Description
AZCW	Set all the information bits to 0.
RAND	Generate randomly the information bits based on the MT 19937 PRNG [Src-MN98].
USER	Read the information bits from a given file, the path can be set with the --src-path parameter.
USER_BIN	Read the information bits from a given file in binary mode , the path can be set with the --src-path parameter.

Note

For the USER type, when the number of simulated frames exceeds the number of frames contained in the files, the frames are replayed from the beginning of the file and this is repeated until the end of the simulation.

Note

For the USER_BIN type, raw data is read from the file that is open in binary mode. When the end of the file is reached, the source goes back to the beginning of the file and continues to generate bits from there.

3.2.2.3. --src-implem

Type

text

Allowed values

FAST STD

Default

STD

Examples

--src-implem FAST

Select the implementation of the algorithm to generate the information bits.

Description of the allowed values:

Value	Description
STD	Standard implementation working for any source type.
FAST	Fast implementation, only available for the RAND source type.

3.2.2.4. --src-path

Type

file

Rights

read only

Examples

--src-path conf/src/GSM-LDPC_2112.src

Set the path to a file containing one or more frames (informations bits), to use with the USER or USER_BIN source type.

With the USER_BIN source type, raw binary data is directly read from the file.

With the USER source type, an ASCII file is expected:

# 'F' has to be replaced by the number of contained frames.
F

# 'K' has to be replaced by the number of information bits.
K

# a sequence of 'F * K' bits (separated by spaces)
B_0 B_1 B_2 B_3 B_4 B_5 [...] B_{(F*K)-1}

3.2.2.5. --src-no-reset

Do not reset the source (start to the beginning) if the file reach EOF and pad with zeros after EOF (work only for USER_BIN source type).

3.2.2.6. --src-fifo

If the FIFO (or pipe) reach the end, then reset the EOF flag and retry to read in loop.

3.2.2.7. --src-start-idx

Type

integer

Default

0

Examples

--src-start-idx 42

Give the start index to use in the USER source type. It is the index of the first frame to read from the given file.

3.2.2.8. References

Src-MN98

M. Matsumoto and T. Nishimura. Mersenne twister: a 623-dimensionally equidistributed uniform pseudo-random number generator. ACM Transactions on Modeling and Computer Simulation (TOMACS), 8(1):3–30, 1998. doi:10.1145/272991.272995.