利用大量外场实验数据,研究了红外测量系统输出灰度及定标背景偏置随环境温度的变化规律,分析了背景偏置变化对面目标辐射测量精度的影响。在此基础上,提出了一种基于背景偏置对消的面目标辐亮度计算新方法。该方法消除了对环境温度依赖较大的背景偏置项的影响,可有效提高动态目标红外辐射特性的测量精度。采用传统方法和新方法对某型飞机的动态特性测试数据进行了处理和比较,结果验证了新方法的有效性。

Based on a large amount of test data, the variations of the output gray value and the calibration background bias of an infrared measurement system with ambient temperature were analyzed. Further, the influence of background bias on the precision of the surface target-radiance measurements was assessed. Based on the results, a new method for calculating the surface target radiance based on background offset cancelling is proposed. This method can improve the measurement accuracy of the infrared radiation characteristics of dynamic targets by eliminating the influence of background bias, which is influenced by ambient temperature. The dynamic characteristics of a particular type of aircraft were calculated and compared using both the traditional and the proposed methods. The results verify the effectivity of the newly proposed method.