Page 177 - ISCI’2017
P. 177

n
             M = ∏   m i .) uniquely determines the corrective possibilities of error-correcting code nonpositional.
                  i= 1
            Correcting codes in SRC can have any value of the minimum  code distance (MCD)  d      min  ) . This
                                                                                                   (SRC
            depends on the values of redundancy  R . In SRC established between redundancy correcting code  R

            , the value  d min  )  of MCD and the number  k  of check bases. Correcting code has a value  d (SRC )  of
                         (SRC
                                                                                                      min
            MCD, if the degree  R  of redundancy is not less than the product of any  d (SRC )  − 1 bases SRC. On
                                                                                      min
            the one hand we have that

                                                           ( SRC
                                                          d min  ) − 1
                                                     R ≥   ∏    m ,
                                                                  i q
                                                            i= 1
            on the other hand, on the other hand –

                                                                    i ∏
                                          R =  M 0  / M = ∏  nk+  m i ∏  /  n  m =  k  m ni+  .
                                                        i= 1    i= 1    i= 1
                                                (SRC
            In this case, legitimately argue that d min  )  −=
                                                      1 k , or
                                                   d min  )  =  k + 1.                                  (1)
                                                     (SRC


               There are two approaches to the problem of ensuring NCS in SRC necessary corrective properties.


               The first approach. Knowing the requirements for correcting the NCS properties, for example, the
            number of errors witch detected t det.  or corrected t cor . , to introduce, by controlling the amount k  or


            magnitude  {m nk+  }  of bases  necessary redundancy  information  R . Information redundancy  R

                                                    (SRC
            determines the minimum code distance  d min  )   NCS  in  SRC.


               Then, in accordance with the theory of error-correcting coding (TECC) for the orderly  (m < m i+ 1 )
                                                                                                     i
            SRC have that

                                                  t det.  ≤  d min  )  −  1,                            (2)
                                                         (SRC
                                                     t det.  ≤  k ;                                     (3)

                                                        d (SRC )  − 1
                                                t cor .  ≤    min    ,                                (4)
                                                          2     

                                                           k 
                                                    t cor .  ≤   .                                    (5)
                                                           2
                                                          
               The second approach. For a given type of NCS  A SRC  = (a 1  || a 2  ||...|| a i−  1  || aa i+  1  ||...|| a n  ||...|| a n k+  )
                                                                                       ||
                                                                                      i
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