The mean radiative temperature ( $T_{mr}$ ) is a key function controlling the sky noise temperature in microwave receiving systems. A generalized parametric prediction (GPP) model of $T_{mr}$ for microwave slant paths in all-weather conditions is formulated and presented. The proposed GPP model is aimed at being multifrequency and surface-temperature scaled, valid for elevation angles from 5° to 90° and for frequencies ranging from 5 to 95 GHz within the three transmission windows delimited by the water vapor and the oxygen absorption peaks. The core of the GPP model is a parametrization driven by a physically based radiative transfer approach taking into account extinction, emission, and multiple scattering. The expression of $T_{mr}$ is normalized to the surface temperature of the considered site. The GPP model is verified with measurements available from the multiinstrument Italian Satellite (ITALSAT) campaign in Spino d’Adda, Milan, Italy, in 1994–1997, obtaining a fractional mean error ranging from 0.045 to 0.068. A comparison of the GPP model with the current ITU-R model shows a reduction in the root mean square error up to about 20 and 30 K, depending on the considered frequency.

中文翻译：

---

全天候条件下微波斜径平均辐射温度的广义参数预测模型

平均辐射温度 ( $T_{先生}$ ) 是控制微波接收系统中天空噪声温度的关键功能。广义参数预测 (GPP) 模型 $T_{先生}$ 制定并介绍了全天候条件下的微波倾斜路径。提议的 GPP 模型旨在进行多频率和表面温度标度，对 5° 至 90° 的仰角和由水蒸气和氧气吸收峰界定的三个传输窗口内的 5 至 95 GHz 的频率范围有效。GPP 模型的核心是由基于物理的辐射传输方法驱动的参数化，同时考虑了消光、发射和多次散射。的表达 $T_{先生}$ 归一化为考虑地点的表面温度。GPP 模型通过 1994 年至 1997 年在意大利米兰斯皮诺达达的多仪器意大利卫星 (ITALSAT) 活动中可用的测量值进行了验证，获得了范围从 0.045 到 0.068 的小数平均误差。GPP 模型与当前 ITU-R 模型的比较表明，根据所考虑的频率，均方根误差降低了约 20 和 30 K。