METHOD FOR DEMODULATING SIGNALS FROM A MULTI-ACCESS SYSTEM ABLE TO COLLIDE AND EQUIPMENT FOR IMPLEMENTING SAME

摘要

The present invention relates to a method for demodulating time-multiplexed signals able to mutually collide, in particular in the case of an AIS (Automatic Identification System), being a communications system between ships which allows collisions between these ships to be limited and which allows the maritime traffic in view from the coasts to be monitored thanks to coastal stations that listen to the communications. When these colliding signals are sufficiently "distinct" (in frequency, in power or in time), algorithms exist for discriminating between them. The demodulator provided in the framework of the invention offers the possibility of demodulating two colliding signals, whose collision parameters (difference in frequency, in power or their non-synchronization) are sufficiently small to make them virtually inaccessible otherwise. This invention therefore allows the satellite AS system to utilize cases of signal collisions that were hitherto detrimental in order to improve the overall performance.