Method of interleaving a binary sequence

Abstract

To interleave a binary sequence a represented by the polynomial a ⁡ ( x ) = ∑ i = 0 n - 1 ⁢ a i ⁢ x i , where n=R.M with R≧M, i being an integer which may be written i=r.M+c, r and c being integers, r≧0 and c ε [0, M−1], there is obtained, from the sequence a, an interleaved binary sequence a*. The interleaved binary data sequence a* represented by the polynomial a * ⁡ ( x ) = ∑ i = 0 n - 1 ⁢ a i ⁢ x i * where i*=[r−h(c)].M+c mod n, the h(c) being obtained by the choice of an M-tuple h0=[h0(0), . . . , h0(M−1)] of non-negative integers less than R−1 such that, given a predetermined set Π of circulating matrices P of dimension M×M, for any matrix P of Π, the residues modulo R of the components of the vector h0.P are not nil; and the corresponding choice of an M-tuple h obtained from h0 by the application of a permutation moving h0(c) to position L×c mod M, the integer L being relatively prime with M. (It is noted that the above underlining of the variables, and the above single bracketing, is in the original and is meant to be permanent.)

Dependencies are inferred from the claim text.