Introduction
New changes to port security address not only the normal or friendly traffic, but also systems that secure the normal port operation, and deter and prevent any hostile operation against the harbor.
The mere cost of an incident that halts normal operation of a major port will incur significant economical and operational consequences to a country or region. In this paper we will discuss threats from intruders, such as surface vessels, underwater vehicles, divers and swimmers, all being targets that will hide their real identity and intent.
Diver detection sonar systems with detection ranges from some hundred meters to 600-800 meters on a good day have been available for some time. But before countermeasures or reaction procedures can be set into operation, the security system will have to perform all the tasks from detection, classification, alerting the operator to confirmation of the threat being real by the operator before the operator chooses the best reaction procedure for the incident.
Studies have shown that the time to perform these tasks will be very limited, and thus work was undertaken to develop sonar and systems with larger detection ranges and integrate them into a system allowing the timely performance of port security.
The project discussed in this paper began in 2007, aiming to develop and test new long-range awareness sonar systems in a real environment at Haakonsvern Naval base, which could form the basis for a permanent installation at the base.
The sonar was to be integrated into a system including other above- and below-water sensors and reactors.
Above-water surveillance
Protection against illicit underwater activities in coastal areas, ports, harbours or in confined areas is complicated by the reverberant conditions, and the normally high levels of surface traffic.
To ease the burden on the operator, the system should only give a warning when something is unusual or abnormal and requires attention. This puts severe requirements on the signal processing and the ability to reliably reduce the number of ‘false alarms’ (i.e. events not requiring the attention of the operator.)
It is therefore very important to combine above-water information with sonar information in order to improve on classification and thus reduce false alarms. There are many VTS (Vessel Traffic Service) and Port Management Systems installed in important ports around the world. These systems already handle all important above-water sensors. Therefore, it was decided to integrate the sonar information in an existing platform, the C-Scope Vessel Traffic Management System, in order to provide a common operational picture on track level, for targets above and below the surface.
