| 摘要 |
PURPOSE:To execute the cascade connection of an arithmetic part and to obtain an error position polynomial and an error evaluation polynomial by decreasing successively a degree while the maximum degree of a syndrome polynomial and an initial polynomial specified by the number of symbols to be corrected is multiplied. CONSTITUTION:As initial conditions, flags CR=H and IX=1 are obtained, a syndrome polynomial S(X), an initial polynomial B(x)=x<2t> and 1 and 0 of the data are inputted to respective P, Q, R and S series transmission lines of a control part 1. To the P type and Q type product sum arithmetic part of an arithmetic part 2 cascade-connected under the control of a cross control circuit 3, S(x) and X<n>B(x) are inputted respectively and to registers 14 and 16, maximum degrees (f) and (g) of these polynomials are respectively and simultaneously loaded. The arithmetic part 2, while the maximum degree of the polynomial S(x) and the polynomial x<2t> is multiplied, decreases successively the degree, and calculates polynomials h(x) and g(x) to satisfy f(x).B(x) +g(x).S(x)=h(x)+g(x), [where, degree of h(x)<degree of g(x)]. These polynomials respectively give an error position and error evaluation polynomial.
|
