基于数字天顶仪的视场角分析

运用数字天顶仪进行定位是一种高精度的天文测量方法。在定位的过程中需要设定概略位置和进行局部星图识别。局部星图识别是在以概略位置为中心的一定范围内进行的。在进行局部星图识别时一般用数字天顶仪的视场角来确定局部星图识别的范围,实际上这是不准确的。通过对数字天顶仪视场角的分析推导了局部星图识别时的经纬度范围,并通过局部星图识别的范围对概略位置进行了研究。实验数据的分析结果表明,在进行局部星图识别时选取的经纬度范围是要大于视场角的,且随着概略位置的设定值逐渐接近测站点真实值,识别的恒星数量也在逐渐增加。

Analysis of field of view angle based on digital zenith camera

Digital zenith camera has high precision in astrogeodesy. Identifying the star partially and setting the approximate position are needed when using digital zenith camera to orient. The scope is around the approximate position during star identification partially. Generally, the scope is usually replaced by field of view angle of digital zenith camera. Actually, this is not correct. The scope of star identification partially was deduced based on the analysis of the field of view angle of digital zenith camera. Then, the approximate position was analyzed according to the scope. The experimental data demonstrates that the range of longitude and latitude of identified stars should be above the field of view angle of digital zenith camera. Also, the recognized star number will rise when the approximate position is close to the true position.