Popis: |
Search and rescue (SAR) and maritime patrol missions pose a number of challenges for an imaging system. Systems must work in low light level, low visibility conditions to find and identify small targets for both search and rescue and law enforcement roles. Passive low light and thermal imaging systems are often unable to discriminate small targets against sea backgrounds due to low thermal contrast and non-cooperative targets. Active gated television (AGTV) as implemented in the ALBEDOS system, enhances the reconnaissance, surveillance, and SAR capabilities of maritime organizations by generating high resolution video imagery regardless of ambient light and conditions or target thermal properties. Active television uses a laser source to illuminate a scene being viewed by a low light television (LLTV) camera, can filter out unwanted light sources, and also limit the image depth of field. AGTV systems generate video for display or recording under conditions that are typically difficult for other sensors. AGTV systems have demonstrated their ability to provide long range detection of SAR targets, to allow the positive identification of people, and to read license plates and ship or aircraft markings covertly at long ranges. This paper summarizes the advantages of AGTV for reconnaissance and surveillance missions, briefly discusses the theories of operation, and compares AGTV performance to that of conventional sensors. A compact airborne AGTV configuration being developed for trials by the Canadian Forces is described. |