TY - JOUR T1 - Hybrid-Level Fusion of Radar Imaging Methods AU - Onat, Emrah AU - Özkazanç, Yakup PY - 2025 DA - October Y2 - 2025 DO - 10.26833/ijeg.1611426 JF - International Journal of Engineering and Geosciences JO - IJEG PB - Murat YAKAR WT - DergiPark SN - 2548-0960 SP - 1 EP - 20 VL - 11 IS - 1 LA - en AB - In this paper, hybrid-level fusion of radar imaging methods generally used in fighter aircraft such as Real Beam Ground Mapping (RBGM), Doppler Beam Sharpening (DBS) and Unfocused Synthetic Aperture Radar (SAR) is explained. Historically, these methods are improved based upon previously developed methods. These methods that are considered in this paper chronologically are investigated in terms of theoretical aspects in detailed. The primary distinction between the methods lies in their cross-range resolutions. However, it is not feasible to generalize the resolution comparison among the methods, as cross-range resolution is influenced by both fixed parameters; such as real antenna beam-width, and dynamic parameters; range, including the aircraft's speed and the angle of the radar beam. These varying factors contribute to the differences in resolution across methods. Because of their some disadvantages against each other, the new method which is the fusion of them is proposed in order to defeat these deficiencies. With the help of the fusion algorithm, a new image can be generated dynamically by using different radar imaging methods for each pixel of the image depending on the real antenna beam width, momentary range, beam position and aircraft speed. So, an image with better resolution can be produced by fusion of radar imaging methods than the image they would produce alone. The article provides details about the hybrid-level fusion algorithm discussed, including its application to a reference image. Both the individual methods and the fusion algorithm were executed for comparison. Additionally, the improved DBS algorithm was also implemented for benchmarking purposes. The final images generated by each method and the fusion algorithm are presented, and evaluation metrics such as Root Mean Square Error (RMSE), Peak Signal to Noise Ratio (PSNR) and Entropy (EN) were calculated to compare the results. KW - Remote Sensing KW - Radar Imaging KW - Real Beam Ground Mapping KW - Doppler Beam Sharpening KW - Synthetic Aperture Radar KW - Hybrid-Level Fusion CR - Moir, I., & Seabridge, A. (2006). Military Avionics Systems-Aerospace Series. ISBN: 9780470016329 CR - Onat, E. (2014). An Investigation of Radar Imaging Methods Used in Fighter Aircrafts, Master’s Thesis, Hacettepe University, Department of Electrical & Electronics Engineering. 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