This paper is mainly aimed at the development requirement of infrared seeker precision guided weapon system. The infrared sensor of seeker is modeled and simulated, and the image sequence is output. The imaging simulation quality of infrared seeker sensor and the adaptability of terminal guidance algorithm based on simulation real-time graph are evaluated from the perspectives of multi-granularity similarity parameter index system construction, multi-saliency fusion feature consistency and bio-visual feature similarity evaluation. At the same time, the analytic hierarchy process (AHP) model is applied to the process of similarity evaluation to solve the comprehensive decision-making problem in multi-index similarity evaluation, and to evaluate the performance of the simulation system from the perspective of the combination of human-computer intelligence, so as to guide the improvement of the simulation system. Based on the above research results, a set of mature and reliable simulation similarity evaluation software is formed. The research results are of great significance to the development and standardization of the whole infrared simulation technology.
Forest canopy height is a very important forest structural attribute. LiDAR and SAR are able to penetrate the forest canopy to obtain information on the understory and canopy vertical structure. But the single data of LiDAR or SAR has its own shortcomings in forest height extraction. We jointly use LiDAR and ALOS PALSAR data to retrieve forest canopy height. First, the extinction degree of the canopy is extracted using airborne LiDAR. The canopy is assumed to be uniform, and the extinction degree is divided by the canopy height to obtain the average extinction coefficient. Then, the extinction coefficient is substituted into random volume over ground (RVoG), and the forest canopy height is obtained. Experimental results showed that the collaborative inversion algorithm based on RVoG model proposed in this paper improves the accuracy of forest canopy height retrieval.
Aiming at vehicle detection on the ground through low resolution SAR images, a method is proposed for determining the region of the vehicles first and then detecting the target in the specific region. The experimental results show that this method not only reduces the target detection area, but also reduces the influence of terrain clutter on the detection, which greatly improves the reliability of the target detection.
When hypersonic vehicles have high-hypersonic flights in the atmosphere, high-temperature IR windows become the main factor of complicated aero-thermo-radiation effects, which would reduce the performance of IR detection systems, or even make these systems fail. By analyzing thermal radiation transfer in IR windows, an experimental platform is established to measure thermo-radiation characteristics of IR window materials. And a method is proposed to evaluate thermo-radiation characteristics of IR windows with uneven temperature distribution. Take a MWIR detection system of a hypersonic vehicle as an example, thermo-radiation characteristics of a sapphire IR window is evaluated. The results indicate that, thermo-radiation characteristics of the sapphire IR window material in 3.7μm-4.8μm have an approximate cubic relationship with temperature at 100°C~350°C. With the rise of temperature, the transmittance of the sapphire material decrease, while the window self-radiation increase. As the sapphire IR window is exposed in high-temperature and high-speed airflow, the transmittance drops 4%, still bigger than 95%, self-radiation enhance about 9 times, while temperature of the window rises rapidly. Self-radiation can drive detector into saturation easily, of which the influence on the MWIR detection system is bigger than that of transmittance.