关键词: 图像增强, 纬度渐长率, 雷达回波, 数字高程模型, 图像处理单元

Abstract: In the traditional method of marine radar echo simulation, large numbers of polygons are obtained using the intersection of scanning fans and Electronic Navigation Chart（ENC）. A method of marine radar echo simulation based on Digital Elevation Model（DEM） image enhancement is proposed in this paper, so as to improve the poor real-time performance and lowly realistic echo image of traditional ones. The method establishes a heterogeneous system of Central Processing Unit（CPU） combined with Graphics Processing Unit（GPU）. The real-time echo is produced via cluster and connecting steps for reducing the number of polygons, after which the echo image is enhanced via the structure of GPU. In order to eliminate the impact of meridianal parts, DEM of the same harbor is used to modify the echo image by splitting harbor map into multiple segments. The process of simulation is according to principle of the producing of radar echo, and the sector-banded texture blending algorithm is used to replace the traditional ones based on the pixel-scan model. The simulation results show that the efficiency of image enhancement using GPU increases in large scenes, thus the overall speedup achieves 240 times than the traditional ones using CPU.

Key words: image enhancement, meridianal parts, radar echo, Digital Elevation Model（DEM）, Graphics Processing Unit（GPU）