Media propagation noises are amongst the main error sources of radiometric observables for deep space missions, with fluctuations of the tropospheric excess path length representing a relevant contributor to the Doppler noise budget. Microwave radiometers currently represent the most accurate instruments for the estimation of the tropospheric delay and delay rate along a slant direction. A prototype of a tropospheric delay calibration system (TDCS), using a 14 channel K_a/V band microwave radiometer, has been developed under a European Space Agency contract and installed at the deep space ground station in Malargüe, Argentina, in February 2019. After its commissioning, the TDCS has been involved in an extensive testbed campaign by recording a total of 44 tracking passes of the Gaia spacecraft, which were used to perform an orbit determination analysis. This work presents the first statistical characterization of the end-to-end performance of the TDCS prototype in an operational scenario. The results show that using TDCS-based calibrations instead of the standard GNSS-based calibrations leads to a significant reduction of the residual Doppler noise and instability.

中文翻译：

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用于高级无线电科学实验的 ESA 对流层延迟校准系统的性能表征

媒体传播噪声是深空任务辐射测量的主要误差源之一，对流层多余路径长度的波动代表了多普勒噪声预算的相关贡献者。微波辐射计目前代表最准确的仪器，用于估计沿倾斜方向的对流层延迟和延迟率。对流层延迟校准系统 (TDCS) 的原型，使用 14 通道 K _a/V 波段微波辐射计是根据欧洲航天局的合同开发的，并于 2019 年 2 月安装在阿根廷马拉圭的深空地面站。盖亚航天器的 44 次跟踪通过，用于执行轨道确定分析。这项工作首次展示了 TDCS 原型在操作场景中的端到端性能的统计特征。结果表明，使用基于 TDCS 的校准而不是基于标准 GNSS 的校准可显着降低残余多普勒噪声和不稳定性。