METHOD OF PERFORMING MULTIPLICATION WITH ACCUMULATION IN A GALOIS BODY

A method is provided for performing multiplication with accumulation in a Galois Field on a first data, a second data, and a third data, with each of the data being coded on 2 n bits. A first multiplication, in the sense of the arithmetic of a Galois Field, is performed on the first data and the n lowest weight bits of the second data to produce a first intermediate result coded on 3 n bits, and a first addition, in the sense of the arithmetic of a Galois Field, is performed on the third data and the first intermediate result to produce a second intermediate result on 3 n bits. A second multiplication, in the sense of the arithmetic of a Galois Field, is performed on the first data and the n highest weight bits of the second data to produce a third intermediate result on 3 n bits, and a second addition, in the sense of the arithmetic of a Galois Field, is performed on the 2 n highest weight bits of the second intermediate result and the third intermediate result to produce a fourth intermediate result coded on 3 n bits. In a preferred embodiment, the 2 n highest weight bits of the second intermediate result are stored in an intermediate register and the n lowest weight bits of the second intermediate result in an output register.