Sensorteknologi for fremtidig UAV
The document addresses the enabling technologies of sensor suite supporting UAV-procurement planning and UAV-system midlife update. According to image interpreters and analysts, an electro optical image is preferred. Provided that the UAV is operating below the sky, the electro optical imaging product received is likely to have very good resolution. To support 24-hour below the sky operations a forward-looking infrared sensor is essential. Electro optics and infrared sensors have limited visibility through clouds. In view of delivering images with better contrast (especially in hazy conditions), visible cameras could be replaced by near infrared cameras. Thermal imagers work fairly in adverse weather conditions and can penetrate moderate natural and manmade obscurants. A synthetic aperture radar (SAR) is considered to be a principal sensor technology. A SAR has day/night capability because it supplies its own illumination. A SAR has all-weather capability because radio waves propagate through clouds and rain with only limited attenuation. Drawback of the SAR is the heavy and sophisticated signal processing. Presently, most UAVs are using on ground SAR signal processing requiring a high information data rate for the down-link in order to send raw SAR data to the ground station. According to this, a high or medium altitude long endurance UAV with imaging radar (SAR), operating together with a low altitude UAV observing with electro optics and thermal sensors is tending to be an optimal solution. The future sensor suite would cover the multi-spectral range of VHF frequency to visible wavelength and the multi-dimensional parameters of contrast, two-dimensional shape, three-dimensional shape, temporal and polarization signatures of the target.