This study carries out the calibration and validation of Antenna Temperature Data Record (TDR) and Brightness Temperature Sensor Data Record (SDR) data from the last National Oceanic and Atmospheric Administration (NOAA) Advanced Microwave Sounding Unit-A (AMSU-A) flown on the Meteorological Operational satellite programme (MetOp)-C satellite. The calibration comprises the selection of optimal space view positions for the instrument and the determination of coefficients in calibration equations from the Raw Data Record (RDR) to TDR and SDR. The validation covers the analyses of the instrument noise equivalent differential temperature (NEDT) performance and the TDR and SDR data quality from the launch until 15 November 2019. In particular, the Metop-C data quality is assessed by comparing to radiative transfer model simulations and observations from Metop-A/B AMSU-A, respectively. The results demonstrate that the on-orbit instrument NEDTs have been stable since launch and continue to meet the specifications at most channels except for channel 3, whose NEDT exceeds the specification after April 2019. The quality of the Metop-C AMSU-A data for all channels except channel 3 have been reliable since launch. The quality at channel 3 is degraded due to the noise exceeding the specification. Compared to its TDR data, the Metop-C AMSU-A SDR data exhibit a reduced and more symmetric scan angle-dependent bias against radiative transfer model simulations, demonstrating the great performance of the TDR to SDR conversion coefficients. Additionally, the Metop-C AMSU-A data quality agrees well with Metop-A/B AMSU-A data, with an averaged difference in the order of 0.3 K, which is confirmed based on Simultaneous Nadir Overpass (SNO) inter-sensor comparisons between Metop-A/B/C AMSU-A instruments via either NOAA-18 or NOAA-19 AMSU-A as a transfer.

中文翻译：

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Metop-C先进微波探测单元-A（AMSU-A）的天线和亮度温度的校准和验证

这项研究对上次飞行的国家海洋和大气管理局（NOAA）先进微波探测装置-A（AMSU-A）上的天线温度数据记录（TDR）和亮度温度传感器数据记录（SDR）数据进行了校准和验证。气象业务卫星计划（MetOp）-C卫星。校准包括为仪器选择最佳空间视图位置，以及确定从原始数据记录（RDR）到TDR和SDR的校准方程式中的系数。验证涵盖从发射到2019年11月15日的仪器噪声等效温差（NEDT）性能以及TDR和SDR数据质量的分析。特别是，通过分别与辐射传递模型模拟和Metop-A / B AMSU-A的观察结果进行比较来评估Metop-C数据质量。结果表明，在轨仪器NEDT自发射以来一直保持稳定，并在除第3通道以外的大多数通道上均符合规范，该通道的NEDT在2019年4月之后超过了规范.Metop-C AMSU-A数据的质量自发布以来，除第3频道外，所有其他频道均可靠。由于噪声超出规格，通道3的质量下降。与它的TDR数据相比，Metop-C AMSU-A SDR数据相对于辐射传递模型模拟显示出减小的且更加对称的扫描角度依赖性，这证明了TDR到SDR转换系数的出色性能。另外，