A generalized erasure channel in the sense of polarization for binary erasure channels
Yuta Sakai, Ken‐ichi Iwata · 2016
The polar transform of a binary erasure channel (BEC) can be exactly approximated by other BECs. Arikan proposed that polar codes for a BEC can be efficiently constructed by using its useful property. This study proposes a new class of arbitrary input generalized erasure channels, which can be exactly approximated the polar transform by other same channel models, as with the BEC. One of the main results is the recursive formulas of the polar transform of the proposed channel. In the study, we evaluate the polar transform by using the α-mutual information. Particularly, when the input alphabet size is a prime power, we examines the following: (i) inequalities for the average of the α-mutual information of the proposed channel after the one-step polar transform, and (ii) the exact proportion of polarizations of the α-mutual information of proposed channels in infinite number of polar transforms.