Method for calculating the duration of communication sessions with a spacecraft under constraints of the communications coverage of the command and tracking station

Consideration is given to a method for calculating the duration of communication sessions of the command and tracking station with a spacecraft (SC), which enables to make an efficient use of the session time when planning control operations in order to avoid their premature performance or contingency termination in the event of constraints in the ground site coverage. Thanks to the developed method, it was possible to identify communication coverage with limited radio visibility and exclude the times of constraints from the total session duration providing a zone of stable radio exchange with SC while performing control operations, thereby increasing reliability of their performance in the communication session. The method was successfully applied in control of the Resurs-P SC constellation, where it demonstrated its capabilities and efficiency. It can be used to control other advanced SC.