Collision Reduction Methods and Decollision Processing Algorithms in the Space Segment of AIS

In the AIS satellite monitoring system, the key problems are the presence of message collisions and Doppler frequency shifts of received signals, which greatly affects the degradation of signal detection quality. This paper considers ways to reduce the probability of message collisions and methods to combat and resolve collisions in the event of their occurrence. The paper studies the efficiency of various non-coherent detection algorithms under the above-described conditions. Joint application of decollision processing algorithms is considered. An increase in the probability of correct detection and demodulation of colliding signals has been demonstrated. In addition, a study was conducted on the influence of the orientation of the antenna system to reduce the probability of collisions occurrence.