Poor mobile phone coverage is a very common problem in large ships. There are two main reasons for this.
The first is that ships are often far from land, and therefore, also far from the nearest base station.
2: The second reason is that ships are made of steel, with small windows, and those windows are usually made of very thick glass. The ship is effectively a “Faraday cage”. A Faraday cage is an enclosed metal box that blocks mobile phone signals. A simple test you can do yourself demonstrates this. Make a phone call using your mobile phone. During the call, place your phone in an old biscuit tin, and close the lid for a few seconds. Take out the phone. The call will have dropped. The closed biscuit tin acts as a Faraday cage and blocks all signal.
On the positive side, there are no objects out at sea that can block the signal like trees and hills and consequently a mobile signal can theoretically reach out more then 40 km from the coastline.
Boost mobile coverage on Large Commercial Ships
Commercial ships are surprisingly large. Take a container ship. Most of the ship is cargo, but the part where the crew lives and works is usually 4 to 6 stories high. It is as big as a modern office block. Not only is the exterior of the ship made of steel, the interior walls are also made of steel. So even if mobile phone signals manage to get into the outermost sections of the living quarters, it is almost impossible to penetrate further into the interior of the ship.
The StellaMarine repeater solves this problem
The solution to this problem is a mobile phone signal repeater which is designed to boost mobile coverage. An omni-antenna should be used as the exterior antenna, as the ship can be any orientation to the base station on land. A low gain omni should be used as these have a wide vertical beam-width, and this is important as ships can tilt during storms etc.
Because large ships have many rooms, it is best to use a 4-port repeater. In this way you will provide excellent connectivity to at least 4 rooms, and possibly more, if extra splitters and internal antennas are used. If you only need 2 of the 4 ports, the unused ports can be left unterminated. They are automatically terminated internally. They can be used at a later date if further coverage is required.
Below is a promo video for the StellaDoradus Marine repeater which shows you how it all works.