A.M. Kuznetsov - Post-graduate Student, Engineer, Open Society «Russian space systems». E-mail: amk.rss@gmail.com A.A. Romanov - Dr. Sc. (Eng.), Deputy Director, Open Society «Russian space systems» A.A. Romanov - Dr. Sc. (Eng.), Professor, Deputy General Director for Science, Open Society «Russian space systems»

For the sake of maritime safety many information and communication systems are mounted on board the ships, one of them is automatic identification system (AIS). Using these systems ships can exchange navigation and service messages in broadcast regime using automatic identification system (AIS), ships positions, velocity, type, sizes and other parameters can be determined after decoding these messages. Owing to SOLAS convetion AIS transponders must be installed at all large passengers and cargo ships, the total number of such ships is 90 thousands. Ships in open sea are continued to transmit AIS signals, power of them is sufficient to receive data on board the low-earth satellite. AIS protocols were not intend for the satellite usage, that-s why AIS signals from several ships can be received simultaneously on board the satellite, making so called «messages collision». Most part of the messages can-t be separated from the collisions and information included in such messages is missed. In this article new algorithm for collision separating is presented. This algorithm doesn-t need any apriori information about the messages that exceeds number of detected ships. The efficiency of using this algorithm is demonstrated on basis of modeled signals processing.

 

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