Construction of Turbo Code Interleavers from 3-Regular Hamiltonian Graphs

In this letter we present a new construction of interleavers for turbo codes from 3-regular Hamiltonian graphs. The interleavers can be generated using a few parameters, which can be selected in such a way that the girth of the interleaver graph (IG) becomes large, inducing a high summary distance. The size of the search space for these parameters is derived. The proposed interleavers themselves work as their de-interleavers.Comment: This paper has been accepted for publication in IEEE Communication Letter

A Trivalent Graph of Girth 17

A family of trivalent graphs is described that includes most of the known trivalent cages. A new graph in this family is the smallest trivalent graph of girth 17 yet discovered