Page 62 - Satellite Communications, Fourth Edition
P. 62

42   Chapter Two

                                From Eq. (2.11):

                                                           nK 1
                                                     K
                                                         2
                                                               2 2
                                                        a (1   e )
                                                        6.544 deg/day
                                From Eq. (2.12):

                                                    d
                                                         K cos i
                                                    dt
                                                         0.981 deg/day


                                From Eq. (2.13):

                                                    d              2
                                                         K(2   2.5 sin   i)
                                                    dt
                                                          2.904 deg/day


                                Example 2.6 Calculate, for the satellite in Example 2.5, the new values for w and
                                Ω one period after epoch.
                                Solution From Table 2.1:
                                       NN   14.23304826 day ; w 0   113.5534°; Ω 0   251.5324°
                                                          −1
                                The anomalistic period is
                                                           1
                                                     P A
                                                          NN
                                                          0.070259 day


                                This is also the time difference (t   t 0 ) since the satellite has completed one rev-
                                olution from perigee to perigee. Hence:

                                                         d
                                                    0      (t   t 0 )
                                                         dt
                                                    251.5324   0.981(0.070259)
                                                    251.601°


                                                       d
                                                     0    (t   t 0 )
                                                       dt
                                                   113.5534   ( 2.903)(0.070259)
                                                   113.349°
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