3.2.4.10.1. Turbo Encoder parameters

3.2.4.10.1.1. --enc-info-bits, -K Required

Type:integer
Examples:--enc-info-bits 1

Set the number of information bits \(K\). The codeword size \(N\) is automatically deduced: \(N = 3 \times K + 4 \times \log_2(ts)\) where \(ts\) is the trellis size.

3.2.4.10.1.2. --enc-type

Type:text
Allowed values:TURBO AZCW COSET USER
Default:TURBO
Examples:--enc-type AZCW

Select the encoder type.

Description of the allowed values:

Value Description
TURBO Select the standard Turbo encoder.
AZCW See the common --enc-type parameter.
COSET See the common --enc-type parameter.
USER See the common --enc-type parameter.

3.2.4.10.1.3. --enc-sub-type

Please refer to the RSC --enc-type parameter.

3.2.4.10.1.4. --enc-json-path

Type:file
Rights:write only
Examples:--enc-json-path example/path/to/the/right/file

Select the file path to dump the encoder and decoder internal values (in JSON format). Those values can be observed with the dedicated Turbo Code Reader available on the AFF3CT website: http://aff3ct.github.io/turbo_reader.html.

Note

Using this parameter will slowdown considerably the encoder and decoder throughputs.

3.2.4.10.1.5. --enc-sub-no-buff

Disable the buffered encoding.

Without the buffered encoding, considering the following sequence of \(K\) information bits: \(U_0, U_1, [...], U_{K-1}\), the encoded bits will be organized as follow: \(X_0^{sn}, X_0^{pn}, X_0^{pi}, [...], X_{K-1}^{sn}, X_{K-1}^{pn}, X_{K-1}^{pi}, X_{0}^{sn^t}, X_{0}^{pn^t}, [...], X_{\log_2(ts)-1}^{sn^t}, X_{\log_2(ts)-1}^{pn^t}, X_{0}^{si^t}, X_{0}^{pi^t}, [...], X_{\log_2(ts)-1}^{si^t}, X_{\log_2(ts)-1}^{pi^t}\), where \(sn\) and \(pn\) are respectively systematic and parity bits in the natural domain, \(si\) and \(pi\) are respectively systematic and parity bits in the interleaved domain, \(t\) the tail bits and and \(ts\) the trellis size.

With the buffered encoding, considering the following sequence of \(K\) information bits: \(U_0, U_1, [...], U_{K-1}\), the encoded bits will be organized as follow: \(X_0^{sn}, [...], X_{K-1}^{sn}, X_{0}^{sn^t}, [...], X_{\log_2(ts)-1}^{sn^t}, X_0^{pn}, [...], X_{K-1}^{pn}, X_{0}^{pn^t}, [...], X_{\log_2(ts)-1}^{pn^t}, X_{0}^{si^t}, [...], X_{\log_2(ts)-1}^{si^t}, X_0^{pi}, [...], X_{K-1}^pi, X_{0}^{pi^t}, [...], X_{\log_2(ts)-1}^{pi^t}\), where \(sn\) and \(pn\) are respectively systematic and parity bits in the natural domain, \(si\) and \(pi\) are respectively systematic and parity bits in the interleaved domain, \(t\) the tail bits and and \(ts\) the trellis size.

3.2.4.10.1.6. --enc-sub-poly

Please refer to the RSC --enc-poly parameter.

3.2.4.10.1.7. --enc-sub-std

Type:text
Allowed values:CCSDS LTE
Examples:--enc-sub-std CCSDS

Select a standard: set automatically some parameters (can be overwritten by user given arguments).

Description of the allowed values:

Value Description
CCSDS Set the --enc-sub-poly parameter to {023,033} according to the CCSDS standard (16-stage trellis) and select the CCSDS interleaver (see the --itl-type parameter).
LTE Set the --enc-sub-poly parameter to {013,015} according to the LTE standard (8-stage trellis) and select the LTE interleaver (see the --itl-type parameter).