为了实现红外光谱被动测距技术的准确测距以及透过率的精确计算, 采用插值法进行了基线拟合算法研究。以氧气A带为例, 利用逐线积分计算出A吸收带两边的带外数据, 采用多种插值拟合方法来拟合, 进行了详细的理论分析和仿真验证。通过几种拟合结果的对比, 多项式插值拟合取得了比较好的结果, 拟合精度最高。结果表明, 多项式插值拟合基线算法为建立透过率和距离等条件的数据库提供了方法, 为被动测距的实时测量提供了坚实的基础。

In order to measure the range accurately and calculate the transmittance precisely with infrared spectrum passive ranging technology, baseline was fitted with interpolation method. Taking oxygen A band as an example, baseline fitting was completed through a variety of interpolation fitting methods making use of both sides of the absorption data from line-by-line radiative transfer model. Meanwhile, detail theoretical analysis and simulation verification were carried out, after comparing several algorithms, the accuracy of polynomial interpolation fitting is the best. The implementation of baseline fitting algorithm provides method for establishing a database of transmittance, distance and other conditions and provides a solid foundation for realization of passive ranging.