| 摘要 |
<p>An apparatus, for use in a Reed-Solomon decoder, calculates coefficients of an error evaluator polynomial, according to OMEGA (X) = 1+(S1+ sigma 1)X+ (S2+S1 sigma 1+ sigma 2)X<2>+...+ (ST+ST-1 sigma 1+ ST-2 sigma 2+...+ sigma T)X<T>, wherein Si is an (i)th syndrome value, sigma i is an (i)th coefficient of an error locator polynomial, i ranging from 1 to T, T being a predetermined number. The apparatus comprises: a coefficient input block (10) for sequentially providing the coefficients ( sigma i) of the error locator polynomial as a first output and the syndrome values (Si) as a second output in a predetermined order; a multiplier (11,31) for sequentially multiplying the first output and the second output provided from the coefficient input block, to thereby sequentially provide multiplication results; T memories (R0...R3), an adder (13,33) for adding each of the multiplication results provided from the multiplier to the contents of one of the T memories, to thereby provide an addition result; and a second multiplexor (17,37) for selectively providing the first output or the addition result to the T memories (R0...R3). Thus, only a single Galois Field multiplier and a single Galois Field adder are necessary for the determination of the error evaluator polynomid OMEGA (X). The apparatus might also comprise a first multiplexor (15a) for providing contents of one of the T memories in a predefined order to said adder (13); and a demultiplexor for providing the first output or the addition result provided from the second multiplexor to one of the T memories, to be stored therein.</p> |
