Frequently Asked Questions
The AIS signal is more or less limited to line of sight to the horizon. From a height of 55 meters I get a range of around 35 miles out to sea. Inland, hills and buildings block the signal reducing the range For areas other than Liverpool, a network of shipping enthusiasts around the country gather their local AIS and contribute it to ShipAIS.
Each site needs an AIS receiver, an outdoor aerial and a PC to process and gather the data which is then sent to ShipAIS over the internet.