void golay24_table_(int cw[]) { // Compute arnd return the table of 4096 codewords for the Golay (24,12) code. // Array y contains the twelve rows (columns) of the parity-check matrix int y[12] = { 0x7ff, 0xee2, 0xdc5, 0xb8b, 0xf16, 0xe2d, 0xc5b, 0x8b7, 0x96e, 0xadc, 0xdb8, 0xb71 }; int c[2]; /* Codeword composed of 12-bit info and 12-bit parity */ int i,j,k; int aux; int weight(int vector); for(k=0; k<4096; k++) { c[0] = k; c[1] = 0; for (i=0; i<12; i++) { aux = 0; for (j=0; j<12; j++) { aux = aux ^ ((c[0] & y[i]) >> j & 1); } c[1] = (c[1] << 1) ^ aux; } cw[k]=4096*c[0] + c[1]; } }