POLAR Encoder Definition

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POLAR encoder

Polar codes are based on this paper by Erdal Arikan "Channel Polarization: A Method for Constructing Capacity-Achieving Codes for Symmetric Binary-Input Memoryless Channels", 2009 block holds common information for encoders and decoders.

Expects values with MSB first. It needs a full information word and encodes it in one pass. Output is a codeword of block_size.

Parameters

Packed Bits
Choose 1 active bit per byte or 8 active bit per byte. if false, VOLK polar encoder is used.
Parallelism
For parallel execution of multiple instances of the block (more info is needed on this)
Dimension 1
For parallelism
Dimension 2
For parallelism
Block size (N)
Codeword size. MUST be a power of 2.
#Info Bits (K)
Represents the number of information bits in a block. Also called frame_size. <= block_size
Frozen Bit Positions
Integer vector which defines the position of all frozen bits in a block. Its size MUST be equal to block_size - num_info_bits. Also it must be sorted and every position must only occur once.
Frozen Bit Values
Holds an unpacked byte for every frozen bit position. It defines if a frozen bit is fixed to '0' or '1'. Defaults to all ZERO.

Example Flowgraph

This flowgraph can be found at [1]

Fecapi polar encoders fg.png

Source Files

C++ files
[2]
Common code
Public header files
[3]
Block definition
[4]