Page 202 - Satellite Communications, Fourth Edition
P. 202

Electromechanical tracking
                                                                  Flat panel antenna


                                                                  Motor for EL scanning
                                                                  Wave-guide distributor

                                                                  Down-converter
                                                                  Tracking PCB

                                                                  Motor for AZ scanning
                                                        (a)

                                                 Combinational tracking

                                                             Flat panel antenna
                                                             Phaseshifters EL scanning
                                                             Wave-guide distributor

                                                             Down-converter
                                                             Tracking PCB

                                                             Motor for AZ scanning


                                                        (b)

                                                   Electronic tracking


                                                             Flat panel antenna

                                                             Wave-guide distributor


                                                             Phaseshifters EL scanning

                                                             Down-converter

                                                             Tracking PCB
                                                        (c)
                              Figure 6.33 Assembly details of a planar array. (a) electromechanical
                              tracking, (b) combined electromechanical and electronic tracking, (c) elec-
                              tronic tracking. (Courtesy of Michael Parnes. Source: http://www.ascor.
                              eltech.ru/ascor15.htm)

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