Lawrence Livermore National Lab work on the Small Boat Threat

In our work, we continue to evaluate concepts of operation for small boat monitoring. For example, in San Francisco Bay we established a simulated choke point using two RHIBs. Each RHIB had a large sodium iodide radiation sensor on board, mounted on the side nearest to the passing potential target boats. Once detections were made, notification over the network prompted a chase RHIB also equipped with a radiation sensor to further investigate the potential target. We have also used an unmanned surface vessel (USV) carrying a radiation sensor to perform the initial discovery. The USV was controlled remotely and to drive by boats in different configurations. The potential target vessels were arranged in a line, as a choke point and randomly spaced in the water. Search plans were problematic when weather,waves and drift complicated the ability to stay in one place.

A further challenge is to both detect and identify the radioactive materials during the drive-by. Our radiation detection system, ARAM, Adaptable Radiation Area Monitor, is able to detect, alarm and quickly identify plausible radionuclides in real time. We have performed a number of experiments to better understand parameters of vessel speed, time, shielding, and distance in this complex three-dimensional space.

At the NMIOTC in September 2009, we employed a dual detector portal followed by a chase. In this event, the challenge was to maintain communications after a lapse. When the chase went past the line-of sight reach of the Tactical Operational Center’s (TOC) antenna, with interference from a fortress island in Suda Bay, Wave Relay extended the network for continued observation. Sodium iodide radiation detectors were mounted on two Hellenic Navy SEAL fast boats. After making the detection one of the portal boats maintained line-of sight while the other pursued the target vessel. Network access via Wave Relay antennas was maintained until the conclusion of the chase scenario.

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Excerpt from www.naval-technology.com

Detection and protection

AIS is a mode of ship self-reporting (identity, position, destination and more) that was originally designed for collision avoidance, but can also be used for security. Military and civilian analysts are developing ways to automatically detect anomalies in ship behaviour that may indicate criminal or terrorist activity while technology developers are advancing ways to collect AIS data in real time on global scales, from shore stations and from space. However, although AIS can help in detecting and prosecuting criminal and terrorist activity involving large ships, it would have been of no use for Mumbai because the Kuber (a 14m fishing vessel) and the landing dinghy (perhaps 5m long) fell well below AIS carriage requirements.

Extension of the AIS carriage requirements to smaller vessels is being debated in Europe, but it is unlikely ever to extend to vessels of the size involved in Mumbai. Other AIS-like self-reporting systems for small boats do exist, and at least one large commercial port now requires all small boats to employ a particular monitoring system.

Tests conducted with radar in the port of La Spezia, Italy, in November 2009 indicate that the probability of detecting non-compliant, non-reporting boats in a busy port would be high. If such monitoring were in place, then the attackers would face a high risk of immediate radar detection in an unregistered boat. The complication of hijacking a registered boat or the exposure to background checks or post investigation if a registered boat of their own were used – each, as a minimum, exerts a degree of deterrence by threat of ruined surprise that was lacking at Mumbai.

“Non-compliance in the face of clear warnings signals hostile intent and justifies a stopping force.”
The practical implications of such measures are vast. 100% small-boat reporting should therefore be viewed as a long-term security enabler in particularly critical ports or during long periods of high threat.

In the short term, random stop and inspection of small boats may be an equally effective deterrent, provided that the attacker’s perceived risk of early detection and loss of surprise is sufficiently high.

Research at the Nato Undersea Research Centre (NURC) gives preliminary indication of the minimum stop-and-inspection levels necessary for such deterrence.

If systematic checks and their deterrence are not possible, then security providers face the challenge of quickly identifying hostile persons amid many benign activities. Hostile intent betrays itself through open displays of non-compliance to rules and challenges that friendly persons would ordinarily obey.

It is usual therefore to create clearly marked exclusion zones around protected assets into which none but authorised personnel are allowed. Strict exclusion can be enforced on a small scale in ports using floating barriers. Some barriers will wreck a fast small boat, others will entangle it with little risk of harm to its occupants, as demonstrated during Tanglex 2009, an exercise that tested pre-deployed and launched non-lethal entanglement barriers. If an exclusion zone and its barriers interfere with essential business in a port, then it may be necessary to post visual demarcation buoys and to challenge and oppose unauthorised boats that disobey or fail to see the floating signage.

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OBJECTIVE: Develop an innovative method to exploit coherent temporal processing techniques in the discrimination of small boats and semi-submersible vessels in the presence of highly variable Doppler spectra characteristics of littoral environments.

DESCRIPTION: Radar detection of small boats and semi-submersible vessels in the littoral environment can be very challenging because the radar reflectivity is masked by the much stronger reflectivity of the surrounding sea. If the Doppler spectra of the small boat’s return can be adequately separated from that of the sea then improved detection performance is possible. The Doppler spectra of the littoral seas varies from being rather homogeneous to being highly inhomogeneous with large discrete Doppler packets associated with free and trapped capillaries riding on surface gravity waves and swell. Likewise the target Doppler spectra of the small boat target set of interest can be highly variable containing relatively narrow Doppler spectra from the vessel itself and a much wider response from the speed dependent boat wake and spray.

The goal of this effort is to develop robust detection, discrimination and tracking techniques for small boat and semi-submersible vessel operations in the littoral environment. In order to be effective, techniques to mitigate target obscuration due to internal clutter motion along with robust and efficient tracking techniques need to be developed. The techniques shall be developed using analytical and numerical analysis combined with strong empirical evidence obtained from representative experiments.

Navy SBIR 2011.1 – Topic N111-020

Visual surveillance has been an active research area due to its crucial role in helping military intelligence and law enforcement agencies to fight against crime and terrorist activities. The goal of a visual surveillance system is to detect abnormal object behaviors and to raise alarms when such behaviors are detected. It is feasible to classify the moving objects in a scene into pre-defined categories, so that their motion behaviors can be appropriately interpreted in the context of their identities and their interactions with the environment.

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