A Carrier Roll Angle Control Algorithm for Satellite Communication

In order to ensure the stability of the satellite communication link, it is necessary to ensure that the antenna of the communication terminal on the carrier directs to the communication satellite in real time.However, the drastic changes of the carrier attitude may cause the antenna of the communication terminal cannot direct to satellite accurately, which resulting the interruption of satellite communication link finally. To solve the problem, a carrier roll angle control algorithm is proposed in this paper. Firstly, it is assumed that the roll angle of the carrier is 0°. Then, according to the position(longitude, latitude, altitude)and the attitude(pitch, yaw, roll) of the carrier, the angle of the antenna directing to communication satellite is calculated and the projection of the direction angle on the cross section of the carrier is obtained. Finally, the included angle of this projection and the above direction of carrier is the optimal roll angle. When the attitude and the position of the carrier are unchanged, this optimal roll angle can make the angle of the antenna directing to communication satellite to be minimized, thus to obtain the antenna gain maximally and improve the performance of satellite communication greatly.