Sensor Pod Handles Ticklish Flying
High-speed military aircraft pose challenges in designing weapons systems that allow the pilot to react within fractions of a second. This important requirement makes ultramodern navigation and targeting systems a condition for mission success. Precise identification of a target, accurate delivery of the weapon, and reliable damage assessment are critical capabilities of a fighter aircraft’s systems.
An airborne targeting and navigation pod from Zeiss Optronik, Oberkochen, Germany, provides all of the required critical features as well as the ability to operate in day, night and adverse weather conditions. The Litening aircraft pod merges targeting and navigation functions into a single system, providing a high-performance multisensor system, according to Bernd Preber. He is the Zeiss vice president for marketing, Central Europe. The Litening pod is easily adaptable to all fighter aircraft.
The pod contains a high-resolution forward looking infrared (FLIR) system with three fields of view, FLIR images projected on a head-up display to enable low-level flight at night using navigation aids, and two high-resolution charge-coupled device (CCD) cameras with different fields of view for daytime operation and target verification. A high-performance laser target designator and rangefinder allow accurate delivery of laser-guided bombs. A laser spot detector also enables cooperative missions with target hand-off. Electronic image processing for derotation and avoidance of breaklock when tracking at the nadir is another Litening feature.
A strap-down inertial navigation system (INS) on the gimbal provides pod-to-aircraft automatic boresighting and improved target tracking during high-g maneuvers and target obscuration, Preber asserts. The versatility of sensor functions are accommodated in the pod through a unique design, he emphasizes. The sensors—FLIR, CCD, laser designator, laser spot detector and INS—are part of the same payload and share the same optical bench leading to a stable boresight of the lines of sight.
In low-level missions, the pilot is supported by the FLIR image superimposed in a 1-to-1 aspect ratio on the head-up display. This allows night flying at very low altitudes. The air-to-ground mission includes detection, recognition and identification of targets—armored vehicles, tanks and bridges—target designation, rangefinding and laser spot detection. In the air-to-air mission, Litening is able to perform identification and tracking of airborne targets.
Another development by Zeiss is a high-definition infrared (HDIR) camera that provides pinpoint reconnaissance capability through its high-resolution images. This sensor system produces an analog and digital video signal that meets international standards for high-definition television.
HDIR consists of modules that can be combined in a thermal camera. The case and telescope, which determines the field of view, are variable. HDIR creates an image of 1,152 lines per 1,920 pixels for early target recognition and acquisition. In comparison with standard thermal cameras, HDIR provides a field of view enlarged five times while maintaining the same resolution. This technology offers nearly four times better resolution within a 33 percent wider horizontal field of view and the same vertical field of view.
Through its thermal resolution, HDIR recognizes objects where there is minimal temperature difference between the objects and their surroundings, and the camera performs well even at long distances. Together with image processing, an intelligent sensor can be formed for automatic 360-degree search and object identification. Automatic target tracking is also possible with extensions and a laser rangefinder and laser target illuminator. —CAR