低空目标探测中的大气折射误差快速算法  

A Fast Algorithm of Atmospheric Refraction Error in Low Altitude Target Detection

作　　者：张瑜[1,2] 翟艳雪 甘利萍[1] 

机构地区：[1]河南师范大学物理与电子工程学院,河南新乡453007 [2]河南省高等学校电磁波特征信息探测重点学科开放实验室,河南新乡453007

出　　处：《雷达科学与技术》2016年第2期220-224,共5页Radar Science and Technology

基　　金：国家自然科学基金(No.61077037)

摘　　要：为了利用雷达对低空和超低空飞行器进行精确探测,必须对影响雷达测量精度的大气折射误差进行实时修正。针对目前大气折射误差计算存在处理时间较长、不能满足实时性要求的现状,提出了一种利用虚高进行折射误差修正的快速算法。根据等效地球半径中电波射线为直线的情形推出计算接近目标真实高度的虚高方法,利用虚高将折射误差公式中的积分项分为两部分,最影响折射误差修正处理时间的部分采用一次积分完成,另一小部分利用变步长的迭代方法完成。仿真实验表明,在保证与目前公认高精度的射线描迹法相同的精度条件下,利用虚高进行大气折射误差修正可实现快速计算,计算速度至少提高一倍,且计算速度随雷达仰角的增大而增快。In order to use radar to accurately detect the low and very low-altitude aircraft,the atmospheric refraction error which influences the measurement accuracy of radar must be corrected in real-time.Taking into account of the current situation that the calculation of atmospheric refraction error needs longer time and cannot meet real-time requirement,this paper proposes a fast algorithm by using virtual-height method to modify the refraction error.Regarding the radio wave ray as straight line in earth＇s equivalent radius,the virtual-height method which can calculate the close height with the true altitude is derived.By using virtual-height the integral terms of refraction error formula can be divided into two parts.One part that has a strong impact on the treatment time of refraction error modification can be calculated by one time integration and the other part can be calculated by variable step iterative method.The simulation results show that the computation time of virtual-height method can reduced by half under the condition of the same precision as the high precision ray tracing method,and the speed gets faster with the radar＇s elevation angle increasing.

关 键 词：低空目标 折射误差修正 快速算法 虚高 等效地球半径 

分 类 号：TN012[电子电信—物理电子学]