Signal amplitude limiter based soft distance decoding algorithm for polar codes over impulsive noise channels

In this paper, the BER performance of a soft distance successive cancellation decoder for Polar codes is analyzed in the presence of impulsive noise, modelled using both the Middleton's Class A model and the symmetric alpha-stable model, for impulsive noise channels. This algorithm avoids estimation of the signal-to-noise ratio of the channel, and simplifies the initialization step of the classic successive cancellation decoder for Polar codes. These two simplifications are obtained without any significant loss in BER performance with respect to the classic SC decoder operating over the same channels, as we show by means of BER performance simulations. Impulsive noise is characterized by strong peak amplitude values that are added to the amplitude of the transmitted signal, thus significantly increasing the BER. A simple strategy based on the use of signal amplitude limiters can be used to mitigate this effect. We have applied limiters to both decoders, resulting in significant BER performance improvements.