Patent ID: 6993698

Claim:
A method of turbocoding for the transmission of information in which, a first polynomial with binary coefficients g(x) of degree d and with a constant term equal to 1 having been predetermined, first the information is presented in the form of binary sequences u of length k=p−d, where p is a predetermined multiple of the period N of the polynomial g(x), and then, for each of said sequences u , there is produced a triplet v of binary sequences ( a , b , c ) intended to be transmitted and obtained as follows: the sequence a is of length p and obtained by extending the sequence u by means of d padding bits so that the polynomial a ⁢ ( x ) = ∑ i = 0 p - 1 ⁢ a i ⁢ x i associated with a is divisible by g(x), the sequence b is represented by the polynomial b ( x )= a ( x )· f 1 ( x )/ g ( x ), where f 1 (x) is a second polynomial with predetermined binary coefficients, without a common divisor with g(x), and the sequence c is represented by the polynomial c ( x )= a *( x )· f 2 ( x )/ g *( x ), where a * ⁢ ( x ) = ∑ i = 0 p - 1 ⁢ a i ⁢ x π ⁢ ( i ) , where π(i) is a predetermined permutation of the integers i lying between 0 and (p−1), where g*(x) is a third polynomial with predetermined binary coefficients, of degree d and with a constant term equal to 1, π(i) and g*(x) being chosen so that, whatever the polynomial a(x) divisible by g(x) (mod. 2), a*(x) is divisible by g*(x) (mod. 2), and where f 2 (x) is a fourth polynomial with predetermined binary coefficients, without a common divisor with g*(x), in which there is taken for π(i) the residue modulo p of the product (i·e), where e is a predetermined strictly positive integer, relatively prime with p, congruent with a power of 2 modulo N, and not congruent with a power of 2 modulo p, from which it results that g*(x) is identical to g(x).