3.2.4.5.1. Polar MK Encoder parameters

3.2.4.5.1.1. --enc-type

Type

text

Allowed values

POLAR_MK AZCW COSET USER

Default

POLAR_MK

Examples

--enc-type AZCW

Select the encoder type.

Description of the allowed values:

Value	Description
POLAR_MK	Select the standard Polar MK encoder.
AZCW	See the common --enc-type parameter.
COSET	See the common --enc-type parameter.
USER	See the common --enc-type parameter.

3.2.4.5.1.2. --enc-sys

Enable systematic encoding. By default the encoding process is non-systematic.

3.2.4.5.1.3. --enc-pc-kernel

Type

list of (list of (boolean:including set={0|1}):limited length [1;inf]), elements of same length

Default

"10,11"

Examples

--enc-pc-kernel "111,101,011"

Set the polar code kernel (squared matrix only).

The Kronecker powers of the kernel matrix \(T_s\) defines the \(G\) generator matrix. The frame size \(N\) can only be a power of the matrix size \(s\). For traditional Polar codes \(s = 2\).

Note

This parameter can only be used to define mono-kernel polar codes.

3.2.4.5.1.4. --enc-pc-path

Type

file

Rights

read only

Examples

--enc-pc-path example/path/to/the/right/place/

Set the path to a file containing the polar code description (kernels definition and stages).

An ASCII file is expected:

# number of different kernels
2

# dimension of kernel 0
2
# kernel 0
1 0
1 1

# dimension of kernel 1
3
# kernel 1
1 1 1
1 0 1
0 1 1

# number of stages
5
# type of kernel per stage
0 0 0 0 1

The previous file describes a Polar MK code which is build from the following Kronecker product: \(G_{48} = T_2 \otimes T_2 \otimes T_2 \otimes T_2 \otimes T_3\) with \(N = 2 \times 2 \times 2 \times 2 \times 3 = 48.\)

Note

When this parameter is used it overrides the --enc-pc-kernel parameter.

Note

This parameter is the only way to define multi-kernel polar codes.

3.2.4.5.1.5. --enc-fb-gen-method

Type

text

Default

GA

Allowed values

GA GAA FILE

Examples

--enc-fb-gen-method FILE

Select the frozen bits generation method.

Description of the allowed values:

Value	Description
GA	Select the GA method from [Pmke-Tri12].
GAA	Select the GA method from [Pmke-Tri12] (works only for Arikan mono-kernel polar codes).
FILE	Read the best channels from an external file, to use with the --enc-fb-awgn-path parameter.

Note

When using the FILE method, the frozen bits are always the same regardless of the SNR value.

3.2.4.5.1.6. --enc-fb-awgn-path

Type

file

Rights

read only

Examples

--enc-fb-awgn-path example/path/to/the/right/place/

Set the path to a file or a directory containing the best channels to select the frozen bits.

An ASCII file is expected, for instance, the following file describes the most reliable channels optimized for a codeword of size \(N = 8\) and for an AWGN channel where the noise variance is \(\sigma = 0.435999\):

8
awgn
0.435999
7 6 5 3 4 2 1 0

Given the previous file, if we suppose a Polar code of size \(N = 8\) with \(K = 4\) information bits, the frozen bits are at the 0, 1, 2, 4 positions in the codeword. The strategy is to freeze the less reliable channels.

Warning

The FILE frozen bits generator expects a file and not a directory.

3.2.4.5.1.7. --enc-fb-dump-path

Type

folder

Rights

write only

Examples

--enc-fb-dump-path example/path/to/the/right/place/

Set the path to store the best channels.

Note

Works only for the GA and GAA frozen bits generation methods.

3.2.4.5.1.8. --enc-fb-noise

Type

real number

Examples

--enc-fb-noise 1.0

Select the noise for which the frozen bits will be optimized.

3.2.4.5.1.9. References

Pmke-Tri12(1,2)

P. Trifonov. Efficient design and decoding of polar codes. IEEE Transactions on Communications (TCOM), 60(11):3221–3227, November 2012. doi:10.1109/TCOMM.2012.081512.110872.