Ship detection probability analysis for a possible long-range AIS system

There is an increasing requirement for global tracking of sea-going vessels. This report investigates the possibility of optimising the existing Universal Shipborne Automatic Identification System (AIS) for long-range AIS (LRAIS), and suggests to do so by implementing; 1) a separate VHF channel for LRAIS, 2) short LRAIS messages, and 3) longer ship reporting interval. The analyses show that the suggested system could be suitable for LRAIS, and that such an LRAIS system could be optimised to handle more than 10 000 ships with a ship detection probability of 99% or better.