POLAR Encoder Definition: Difference between revisions

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== Example Flowgraph ==
== Example Flowgraph ==


Insert description of flowgraph here, then show a screenshot of the flowgraph and the output if there is an interesting GUI. Currently we have no standard method of uploading the actual flowgraph to the wiki or git repo, unfortunately. The plan is to have an example flowgraph showing how the block might be used, for every block, and the flowgraphs will live in the git repo.
This flowgraph can be found at [https://github.com/gnuradio/gnuradio/blob/master/gr-fec/examples/fecapi_polar_encoders.grc]
 
[[File:Fecapi_polar_encoders_fg.png|800px]]


== Source Files ==
== Source Files ==

Latest revision as of 15:02, 7 December 2020

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]