POLAR code channel construction.
polar_channel_construction exposes functionality to calculate polar channels for different sizes. It may be used to calculate Bhattacharyya parameters once and store them in a file in '~/.gnuradio/polar'. Frozen bit positions are recalculated on every run.
polar_channel_construction provides a command-line interface for all the channel construction code. These features are also accessible via the Polar Configurator block in GRC.
BEC channel construction can be calculated explicitly because the BEC represents a special case which simplifies the task. All functionality regarding this channel is located in 'channel_construction_bec'.
In general channel construction for polar codes is a very time consuming task. Tal and Vardy proposed a quantization algorithm for channel construction which makes it feasible. The corresponding implementation is located in 'channel_construction_awgn'. It should be noted that this more of a baseline implementation which lacks all the advanced features the original implementation provides. However, simulations show that Bec channel construction with a design-SNR of 0.0dB yields similar performance and should be preferred here.