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: AZCWRANDUSERUSER_BINDefault: RANDExamples: --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 [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: FASTSTDDefault: STDExamples: --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¶
| [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. |