The planning of sessions during the data relay and communication control with the help of MSDRS “Luch”
Central Research Institute of Machine Building, 4, Pionerskaya st., Korolev, Moscow region, 141070, Russia
The article presents materials about creation of general (long-term) and detailed (daily) plans for conducting of data relay and communication sessions in the Data Relay and Communications Control Center of Multifunctional Space Data Relay System “Luch”.
The planning of information relaying different types is carried out on the basis of applications consumers — Mission control centers of Low Earth Orbit spacecraft (SC), boosters, launch vehicles. Requests are subdivided: on long-term ones – during a weekly period, operational ones – are distributed in less than one day before the planned work beginning, emergency ones – may be issued in less than 3 hours before the planned relay session. Managing Space Objects are taking advantage of up to 3 relay satellites.
The aim of this work is to offer a satisfaction methodology of multiple received varying degrees of urgent requests with given limitations of applications by ground relay stations (GRC) and airborne relay systems, exceptions enabled the same ground relay stations by various spacecraft-subscribers with overlapping range of communications sessions opportunities. Hence it is needed to address the optimization of planning relay sessions.
As the objective planning mission function is taken by the functional, so we need to take into account the implementation of the planned relay sessions with the resource use of ground relay stations. The criterion of plan optimality is to ensure the maximum number of declared sessions presented to the alignment of all remaining resources used by GRC.
To solve the problem of optimal planning relay and communications sessions is used a so-called greedy algorithm. For this task, the principle of optimality can be formulated as follows: for the first step we obtain the certain (running) solution to the spacecraft (SCm) using a “greedy” algorithm. Then, the best solution to sessions distribution for the next spacecraft (SCm+1) is the set of “close” and current solutions. The resulting solution will be a new current solution. This process is repeated until you have examined distribution of sessions for all declared spacecraft.
The resulting method allows for anyone to quickly obtain a practical solution, which is close to the optimum.
So, one of the basic problem was scrutinized by the Data Relay and Communications Control Center of the sessions planning.
The methodology and the obtained results are interesting for researchers in the field of space technology, as well as for graduate and undergraduate students.
Keywords:data relay, communication, planning
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