Interleavers for turbo codes that yield a minimum distance growing with blocklength

This paper presents the study of interleavers that both use a reduced amount of random choice and moderate algebraic structure. The interleaver is essentially chosen at random among a family that produces quasicyclic turbo codes. A typical interleaver produces a turbo code with minimum distance log N. For moderate lengths these interleavers turn out to be also quite practical, comparing favorably with S-random interleavers in a number of instances.