An apparatus and a method. The apparatus includes a receiver including an input for receiving a codeword of length mj, where m and j are each an integer; a processor configured to determine a decoding node tree structure with mj leaf nodes for the received codeword and receive an integer i indicating a level at which parallelism of order m is applied to the decoding node tree structure; and m successive cancellation decoders (SCDs) configured to decode, in parallel, each child node in the decoding node tree structure at level i.