等距圆量距法在海图上的扩展应用研究

为了解决双重极球面投影极区航海图上准确便捷量距的问题,根据等角纬度和大地纬度的关系,从理论和数值方面分析了将等距圆量距法推广应用到双重极球面投影海图的可行性、误差水平并给出了修正公式,以满足双重极球面投影航海图的极区导航应用需要。并研究了将等距圆量距法扩展到基于大地纬度应用的可行性,以满足双重极球面投影极区航海图上便捷准确的量距需要。误差分析表明,双重极球面投影海图上,基于大地纬度的等距圆量距法可行,量距误差可按相应公式修正。

The Extended Application of Distance-measuring Method Based on Stereographic Charts

In order to solve the problem of accurately and conveniently measuring distance on the nautical chart of the double polar sphere projection plane,according to the relationship between the equilateral latitude and the latitude of the earth,this paper analyzes the feasibility and numerical aspects of using equidistant circular distance method for the double polar sphere projection,and analyzes the error level and gives the correction formula to meet the needs of the double polar sphere projection sailing chart for navigation in polar region.The feasibility of extending equidistant-circle distance-measuring method on geodetic latitude instead of conformal latitude is also studied in this paper.Theoretical and numerical error analysis results indicate the feasibility of the method based on geodetic latitude on double stereographic polar charts.The results also show that distance-measuring errors can be corrected by the proposed formulas.