ABSTRACT
In 1948 the world’s first harbour surveillance radar was installed, overlooking the approach to the Port of Liverpool. The facility was supplemented by the use of portable VHF radio equipment. From this beginning, a wide variety of vessel traffic services (VTS) has developed. Some facilities are to this day quite simple, being limited to the ability to broadcast routine general information. At the other extreme, highly complex traffic management centres exist. The latter may employ as many as thirteen VHF communication channels and thirty radars linked by a microwave network to one or more control centres. At such centres, computers process and analyse not only the radar signals but a host of other data relevant to the movement of traffic in the port.
