Page 1288 - 5G Basics - Core Network Aspects
P. 1288

2                                                 Transport aspects


                                             . 0  340362                 for    y   40   ppm

                                              0.268908               for    y    0  ppm             (I-18)
                                               . 0  878177               for    y   40   ppm

            In addition, stuff ratios of −2 and +1 are obtained for frequency offsets of −113.65 ppm and 83.30 ppm,
            respectively. The range of frequency offset that can be accommodated is approximately 197 ppm. This is
            50% larger than the range that can be accommodated by a +1/0/−1 justification scheme (see above), and is
            due to the additional positive stuff byte.

            ODU2 into ODU3 multiplexing
            The ODU2 nominal client rate is (see clause 7.3):
                                                         239
                                                     S       4 ( R 16    )                             (I-19)
                                                         237
            The ODU3 nominal frame time is:

                                                          ( 3824 )(  ) 4
                                                    T                                                  (I-20)
                                                         239 ( 16R  )
                                                         236     16
            The fraction p is 0.25. Inserting into equation I-3 produces:

                                         239        ( 3824 )(  ) 4  
                                             4 R 16                 3808   N                        (I-21)
                                         237       239 ( 16 R )    4
                                                   236     16
            Simplifying and solving for  produces:

                                                  236
                                                    ( 15296 )   4 N  15232                         (I-22)
                                                  237

            As before, let  = 1 + y, where y is the net frequency offset (and is very nearly equal to yc − ys for client and
            server frequency offset small compared to 1). Then:
                                          236                         236
                                            ( 15296 )  15232  4 N    ( 15296  y )
                                          237                         237                               (I-23)
                                             4 N   . 0  5400844  15231 . 459916 y

            The number of fixed stuff bytes N is zero, as given in clause 19.5.3. The client and mapper frequency offsets
            are in the range 20 ppm, as given in clause 7.3. Then, the net frequency offset y is in the range 40 ppm.
            Inserting these values into equation I-23 gives for the range for :
                                            . 0  0691740                  for    y   40   ppm


                                              . 0  540084 4                for    y    0 ppm        (I-24)
                                              . 1  149343                  for    y   40   ppm

            In addition, stuff ratios of −2 and +1 are obtained for frequency offsets of −95.85 ppm and 101.11 ppm,
            respectively. As above, the range of frequency offset that can be accommodated is approximately 197 ppm,
            which  is  50%  larger  than  the  range  that  can  be  accommodated  by  a  +1/0/−1  justification  scheme  (see
            above) due to the additional positive stuff byte.










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