The attitude and orbit control subsystem (AOCS) provides attitude information communications service equipment, and scientific instruments. Control is. An operating communications satellite system consists of Physical Structure. Attitude and Orbit Control System. (AOCS). Power System. Thermal Control. oriented framework for Attitude and Orbit Control System or AOCS of satellites. Understanding the case study requires some familiarity with the AOCS domain.

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The maximum rotation speed of the reaction wheels is rpm. All eventual failures must be detected. Based on telemetry data received from the satellite and sztellite data obtained from the tracking system, the control system is used to correct the position and attitude of the satellite.

The TTCM subsystem present at earth station monitors the position of satellite. Altitude control subsystem takes care of the orientation of satellite in its respective orbit. You can also try this books 1. For redundancy XMM-Newton carries a second star-tracker telescope. The satellites, which perform this kind of operation are called as de-spin.

Satellite Communication – AOC Subsystem

So, the second gas jet will communicatkon the motion of satellite in that axis direction. Note that this is not a bright source avoidance cone, but driven by requirements on the spacecraft’s alignment with respect to the Sun to ensure sufficient energy supply and thermal stability. It is responsible for the detection of anomalies of whatever origin and their correction. Create your website today. All communications satellite derive their electrical power from solar cells.


ESA Science & Technology: Engineering

The power is used by the communications system, mainly in its transmitters, and also by all other electrical systems on the satellite. The communication subsystem is the major part of the satellite. The telemetry system sends data derived from many sensors on the satellite, which monitor the satellites health, via telemetry link to the controlling earth station.

In this method, we can stabilize the satellite by using one or more momentum wheels. A satellite which uses multiple frequency bands usually has four or more antennas.

Reaction wheel courtesy of MMS. By continuing to use the site you are agreeing to our use of cookies. We know that satellite may deviates from its orbit due to the gravitational forces from sun, moon and other planets.

Attitude and orbit control system(AOCS) | Satellite Communication

They will provide the rotation in both directions of the three axes. If there is a change in altitude of the satellite, then the angles between the respective aovs will be changed.

In general, it can be rotated at 30 to rpm in order to produce a force, which is of gyroscopic type. The orientation of a satellite in space is crucial, whether it be for telecommunications or Earth observation craft, or for astronomy missions like XMM-Newton.

The direction of this motor will be opposite to the rotation commnuication satellite body, so that the antennas point towards earth. Given XMM-Newton’s very specific orbit highly elliptical, irregular eclipse seasons, Sun avoidancethis required very complex hardwired logic within the unit.


In this method, the body of the satellite rotates around its spin axis.

Communication subsystem is placed on top of the drum. In this way, the AOC subsystem takes care of the satellite position in the right orbit and at right altitude during entire life span of the satellite in space. This drum is covered with solar cells. In addition, a solar communicaation angle within the range must be maintained at all times.

Altitude and Orbit Control AOC subsystem consists of rocket motors, which are capable of placing the satellite into the right orbit, whenever it is deviated from the respective orbit. Due to this, the spin axis gets stabilized and the satellite will point in the same direction.

This subsystem consists of rocket motors that are used to move the satellite back to the correct orbit when external forces cause it to drift off station and gas jets or inertial devices that control the attitude of the satellite.

These three axes define the altitude of satellite. These systems are partly on the satellite and partly at the controlling earth station. The fully redundant AOCS represents some kg of electronics: