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 power is used by the communications system, mainly in its transmitters, and also by all other electrical systems on the satellite. The receiver-transmitter units are known as transponders.

This site was designed with the. 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. In this method, the body of the satellite rotates around its spin axis.

Attitude and orbit control system(AOCS) | Satellite Communication

Missions Show All Missions. So, the second gas jet will stop the motion of satellite in that axis direction. The maximum rotation speed of the reaction wheels is rpm.

Learn all you need in order to create a. The AOCS has also been designed to enable the satellite to operate in an autonomous mode for 36 hours, and during eclipses.

Then, it will resolve that issue by bringing the satellite into the correct orbit. Altitude and Orbit Control AOC subsystem consists of rocket motors, which are capable of placing the satellite into the right xommunication, whenever it is deviated from the respective orbit.


This drum is covered with solar cells. The tracking system is located at this earth station and provides information on the range and the elevation and azimuth angles communicatoin the satellite.

Likewise it will never point to within Most satellite antennas are designed to operate in a single frequency band, for example, C band or Ku band. If there is any change in satellite orbit, then it sends a signal regarding the correction to Orbit control subsystem.

If there is a change in altitude of the satellite, then the angles between the respective axes will be changed. Satellites are of this type are called as spinners.

Given XMM-Newton’s very specific orbit highly elliptical, irregular eclipse seasons, Sun avoidancethis required very complex hardwired logic within the unit. Before delivery for integration into the spacecraft, the AOCS system underwent several weeks of intensive testing, and subsequent System Validation Tests on the assembled satellite have confirmed its perfect operation.

It is usually composed of one or more antennas, which receive and transmit over wide bandwidths at microwave frequencies, and a set of receivers and transmitters that amplify and retransmit the incoming signals.

Let X, Y and Z are another set of Cartesian axes. A satellite which uses multiple frequency bands usually has four or more antennas.

For redundancy XMM-Newton carries a second star-tracker telescope. All eventual failures must be detected.


The communication subsystem is the major part of the satellite. These three axes define the altitude of satellite. Following xatellite the two methods to make the satellite that is present in an orbit as stable.

However, should any serious anomaly occur, such as a prolonged loss of contact, XMM-Newton will automatically enter a survival mode and wait for direct control to be ssatellite from Earth. These systems are partly on the satellite and partly at the controlling earth station. In general, it can be rotated at 30 to rpm in order to produce a force, which is of gyroscopic type. A vital requirement of the XMM-Newton mission is that its delicate science detectors cmmunication not be damaged by luminous sources in the sky.

ESA uses cookies to track visits to our website only, no personal information is collected. They will provide the rotation in communicatipn directions of the three axes.

The letter use is housekeeping, since these subsystems serve to support the communications system.

Satellite Communication – AOC Subsystem

Reaction wheel courtesy of MMS. An electric motor drives this communication system. The orientation of a commmunication in space is crucial, whether it be for telecommunications or Earth observation craft, or for astronomy missions like XMM-Newton.

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