红外与激光工程
紅外與激光工程
홍외여격광공정
INFRARED AND LASER ENGINEERING
2013年
6期
1502-1507
,共6页
唐圣金%郭晓松%周召发%蒲鹏程
唐聖金%郭曉鬆%週召髮%蒲鵬程
당골금%곽효송%주소발%포붕정
星敏感器%质心法%亚像元%三次样条插值%非线性加权
星敏感器%質心法%亞像元%三次樣條插值%非線性加權
성민감기%질심법%아상원%삼차양조삽치%비선성가권
star tracker%centroid algorithm%sub-pixel%cubic spline interpolation%nonlinear weighting
为提高星点图像的质心提取精度,针对星点亚像元定位的系统误差和随机误差提出了一种改进补偿方法。采用三次样条插值函数表示质心位置与系统误差之间的关系,利用该函数进行系统误差补偿,极大地减小了误差采样点的数量和计算量。为了进一步抑制随机误差的影响,在系统误差补偿的基础上,采用非线性加权算法计算星点质心位置,并通过仿真实验确定了该算法的最优加权系数。在没有加入噪声的情况下,改进算法可以将质心法的精度从1/50 pixel提高到10-4 pixel;加入服从N(0,22)分布的高斯白噪声后,改进算法可以达到0.0054pixel的精度,远小于质心法的0.0184pixel。实验结果表明:文中提出的改进补偿算法计算简单,精度高于质心法,满足了高精度星敏感器质心提取的要求。
為提高星點圖像的質心提取精度,針對星點亞像元定位的繫統誤差和隨機誤差提齣瞭一種改進補償方法。採用三次樣條插值函數錶示質心位置與繫統誤差之間的關繫,利用該函數進行繫統誤差補償,極大地減小瞭誤差採樣點的數量和計算量。為瞭進一步抑製隨機誤差的影響,在繫統誤差補償的基礎上,採用非線性加權算法計算星點質心位置,併通過倣真實驗確定瞭該算法的最優加權繫數。在沒有加入譟聲的情況下,改進算法可以將質心法的精度從1/50 pixel提高到10-4 pixel;加入服從N(0,22)分佈的高斯白譟聲後,改進算法可以達到0.0054pixel的精度,遠小于質心法的0.0184pixel。實驗結果錶明:文中提齣的改進補償算法計算簡單,精度高于質心法,滿足瞭高精度星敏感器質心提取的要求。
위제고성점도상적질심제취정도,침대성점아상원정위적계통오차화수궤오차제출료일충개진보상방법。채용삼차양조삽치함수표시질심위치여계통오차지간적관계,이용해함수진행계통오차보상,겁대지감소료오차채양점적수량화계산량。위료진일보억제수궤오차적영향,재계통오차보상적기출상,채용비선성가권산법계산성점질심위치,병통과방진실험학정료해산법적최우가권계수。재몰유가입조성적정황하,개진산법가이장질심법적정도종1/50 pixel제고도10-4 pixel;가입복종N(0,22)분포적고사백조성후,개진산법가이체도0.0054pixel적정도,원소우질심법적0.0184pixel。실험결과표명:문중제출적개진보상산법계산간단,정도고우질심법,만족료고정도성민감기질심제취적요구。
In order to improve the accuracy of centroid location for star images, a modified systematic error compensation algorithm was proposed. First, the cubic spline interpolation function was used to represent the relationship of the systematic error and the actual position and compensate the systematic error. By using the cubic spline interpolation method, the number of error sample points and computational complexity was reduced greatly. Finally, after compensating the systematic error, the nonlinear weighting method were applied to reduce the effects of random error and the optimal weighting coefficient was obtained by the simulation experiment. The simulation results show that the accuracy of star position can be enhanced from 1/50 pixel to 10-4 pixel by using the modified compensation algorithm. When the additive Gaussian noise in the star image obeys N (0,22) distribution, the accuracy of modified compensation algorithm 0.005 4 pixel, which is far less than 0.018 4 pixel from the common centroid algorithm. The conclusions show that the modified compensation algorithm can satisfy the requirement of the high accuracy centroid location for star images due to its simple calculation and accurate result.