针对红外辐射计标定中的数据拟合问题，提出了一种基于PSO-AMLS算法的数据拟合方法。该方法结合了粒子群算法(PSO)和自适应移动最小二乘法(AMLS)。采用的PSO算法可以实现自适应移动最小二乘法中参数的最优化，提高了红外辐射计的校准精度。区别于传统的应用于红外辐射计校准中的数据拟合方法，文中提出的基于局部近似的PSO-AMLS数据拟合方法，不仅可以得到红外辐射计输出电压与准直辐射源辐射之间的对应关系，而且在数据处理中通过灵活的数据处理机制，可以降低因拟合数据不均匀分布对拟合结果产生的不利影响。实验结果表明，文中提出的PSO-AMLS数据拟合方法，优于红外辐射计校准中所用的传统数据拟合方法，可以提高数据拟合精度。

红外辐射测量技术是表征目标红外特征的重要手段，而大气修正是获得目标真实辐射的必要步骤。提出了一种提高远距离目标红外辐射测量精度的非线性大气修正（NLAC）方法。该方法利用近距离标准参考源测量（NRSRM）来计算实时环境中不同位置的实际大气透过率和程辐射。相应条件下的理论大气透过率和程辐射也可以从大气辐射传输软件中获得。应用神经网络技术对两者之间的非线性关系进行拟合。因此，可以预测远距离的大气透过率和程辐射，以实现大气修正。为了进行比较，还进行了简单的线性大气修正（LAC）与线性增强大气修正（LEAC）。实验结果表明，该方法的红外辐射测量平均误差为6.45%，远低于常规方法，线性大气修正方法和线性增强大气修正，分别为16.17%，11.27%和7.44%。

An absolute cryogenic radiometer (ACR) with a detachable optical window was designed and built for high accuracy optical radiant power measurement and photodetector spectral responsivity calibration. The ACR receiver is an electroplated pure copper cavity with a 50-μm-thick wall and inner surface coated with a specular black polymer material mixed with highly dispersible carbon nanotubes. The absorptivity of the cavity receivers was evaluated to be ≥0.9999 in the 250 nm–16 μm wavelength range and ≥0.99995 in 500 nm–16 μm. The cavity receiver works at the temperature of ～5.2 K with nanowatt-level noise-equivalent power. The relative standard uncertainty is 0.041% for the measurement of ～100 μW optical radiant power (250 nm–16 μm) and 0.015% for ～1 mW (500 nm–16 μm).

In this Letter, a method based on the effects of imperfect oscillators in lasers is proposed to distinguish targets in continuous wave tracking lidar. This technique is based on the fact that each lidar signal source has a specific influence on the phase noise that makes real targets from the false ones. A simulated signal is produced by complex circuits, modulators, memory, and signal oscillators. For example, a deception laser beam has an unequal and variable phase noise from a real target. Thus, the phase noise of transmitted and received signals does not have the same power levels and patterns. To consider the performance of the suggested method, the probability of detection (PD) is shown for various signal-to-noise ratios and signal-to-jammer ratios based on experimental outcomes.