Apolar coding method comprising: determining, from N sub-channels that are defined by a code and that have associated reliabilities for input bits at N input bit positions, a number Kof the sub-channels to carry bits that are to be encoded; determining a partial order of the N sub-channels, wherein the partial order defines an order of the N subchannels with respect to their reliability and wherein not every sub-channel has a reliability relative to all other sub-channels that is transmission independent, wherein the partial order comprises a plurality of groups of sub-channels comprising subsets of the N sub-channels, wherein reliability increases with each group from the bottom to the top of the partial order in the sense that each group includes one or more subchannel(s) having a higher reliability than a sub-channel in a lower group and one or more subchannels having a lower reliability than a sub-channel in a higher group, the method further comprising: determining, based on one or more coding parameters, a localization area that includes a plurality of the N sub-channels and is located below fewer than K of the N sub-channels in the partial order of the N sub-channels; by determining a group of the plurality of groups to which a Kth sub-channel from a highest end of the partial order belongs; determing the localization area as a number of groups adjacent to and including the group to which the Kth sub-channel from the highest end of the partial order belongs selecting the fewer than K sub-channels of the N sub-channels above the localization area in the partial order; selecting a number of sub-channels from the plurality of sub-channels in the localization area, wherein the selected fewer than K sub-channels and the number of sub-channels selected from the plurality of sub-channels in the localization area comprise K sub-channels to carry the bits that are to be encoded; encoding the bits that are to be encoded onto the K selected sub-channels to generate codewords, and transmitting the codewords. determining, from N sub-channels that are defined by a code and that have associated reliabilities for input bits at N input bit positions, a number Kof the sub-channels to carry bits that are to be encoded; determining a partial order of the N sub-channels, wherein the partial order defines an order of the N subchannels with respect to their reliability and wherein not every sub-channel has a reliability relative to all other sub-channels that is transmission independent, wherein the partial order comprises a plurality of groups of sub-channels comprising subsets of the N sub-channels, wherein reliability increases with each group from the bottom to the top of the partial order in the sense that each group includes one or more subchannel(s) having a higher reliability than a sub-channel in a lower group and one or more subchannels having a lower reliability than a sub-channel in a higher group, the method further comprising: determining, based on one or more coding parameters, a localization area that includes a plurality of the N sub-channels and is located below fewer than K of the N sub-channels in the partial order of the N sub-channels; by determining a group of the plurality of groups to which a Kth sub-channel from a highest end of the partial order belongs; determing the localization area as a number of groups adjacent to and including the group to which the Kth sub-channel from the highest end of the partial order belongs selecting the fewer than K sub-channels of the N sub-channels above the localization area in the partial order; selecting a number of sub-channels from the plurality of sub-channels in the localization area, wherein the selected fewer than K sub-channels and the number of sub-channels selected from the plurality of sub-channels in the localization area comprise K sub-channels to carry the bits that are to be encoded; encoding the bits that are to be encoded onto the K selected sub-channels to generate codewords, and transmitting the codewords. selecting a number of sub-channels from the plurality of sub-channels in the localization area, wherein the selected fewer than K sub-channels and the number of sub-channels selected from the plurality of sub-channels in the localization area comprise K sub-channels to carry the bits that are to be encoded; encoding the bits that are to be encoded onto the K selected sub-channels to generate codewords, and transmitting the codewords.