Patent ID: 6404360
Filing Date: 2002-06-11
Classification: H03M

Abstract:
Permutation method, characterised in that it makes an output rank from 0 to rÂ·mâˆ’1 correspond to each input rank from 0 to rÂ·mâˆ’1, the said method including the following steps:E1â€”a matrix S having r rows and m columns is considered, filled row by row by the successive numbers from 0 to rÂ·mâˆ’1, E2â€”each column in said matrix S is divided into a predetermined number &lgr; of sub-columns, such that r/&lgr; is not prime, E3â€”the sub-columns of S equal in number to &lgr;Â·m are designated by S&lgr;1&lgr;2 with 0&lE;&lgr;1&lE;&lgr;âˆ’1 and 0&lE;&lgr;2&lE;mâˆ’1 where &lgr;2 refers to the column of S where S&lgr;1&lgr;2 appears and &lgr;1 refers to the position of the sub-column S&lgr;1&lgr;2 in the column of index &lgr;2. E4â€”each sub-column S&lgr;1&lgr;2 is then written in the form of a matrix with R rows and M columns (with r/&lgr;=RM) and in this form it is interleaved by an interleaver of the so-called â€œwheelâ€  type defined by a circular permutation of each column of said matrix with R rows and M columns, said interleaver not being identity, E5â€”this matrix with R rows and M columns is reconverted, after said circular permutations on its columns, into a sub-column S*&lgr;1&lgr;2 which will occupy, in a matrix S*, the same position as that occupied by S&lgr;1&lgr;2 in the matrix S, E6â€”the permutation table consists of pairs each formed by an element of the matrix S and the element with the same position in the matrix S*.