Patent ID: 6560362
Filing Date: 2003-05-06
Classification: G06T,H03M

Abstract:
Encoding method, characterised in that:1/ it takes into account: two predetermined integers M1 and M2, equal to or greater than 1, a number K, greater than or equal to 1, of sequences ai (i=1, . . . ,K) of binary data representing a physical quantity, each sequence ai having: a polynomial representation ai(x) which is a multiple of a predetermined polynomial gi(x), and a number of binary data items equal to the product of any integer number M and the integer N0, the smallest integer such that the polynomial xN0+1 is divisible by each of the polynomials gi(x); 2/ it has an operation of convolutional encoding of the sequences ai into K+M2 intermediate sequences di, 3/ it has a first production operation for a number (K+M2)*M1 of permuted sequences, dij*, (i=1, . . . ,K+M2; j=1, . . . ,M1), each sequence dij* being obtained by a permutation of the corresponding sequence di, the said permutation being, in a representation where the binary data items of each sequence di are written, row by row, into a table with N0 columns and M rows, the result of any number of elementary permutations, each of which: either has the property of transforming the cyclic code of length N0 and with generator polynomial gi(x) into an equivalent cyclic code with generator polynomial gij(x) which may be equal to gi(x), and acts by permutation on the N0 columns of the table representing di, or is any permutation of the symbols of a column of the said table; and having, in consequence, a polynomial representation dij*(x) which is equal to a polynomial product cij(x)gij(x), at least one permuted sequence aij* being different from the corresponding sequence ai; 4/ it has a second production operation for M1 redundant sequences, the polynomial representation of which is equal to &Sgr;fij(x)cij(x), for i=1, . . . , K+M2 and j=1, . . . ,M1, each polynomial fij(x) being a polynomial of degree at most equal to the degree of the polynomial gij(x) with the same indices i and j.