26 Mar 2025
| 26 Mar 2025
Frequency-Dependent Variations of the Antenna Reflection Coefficient Due to Different Wetness Conditions on the Antenna Radome
Department of Electrical Engineering, School of Computation, Information and Technology, Technical University of Munich, 80290 Munich, Germany
Christian Chwala
Institute of Meteorology and Climate Research, Karlsruhe Institute of Technology, 82467 Garmisch-Partenkirchen, Germany
Institute of Geography, University of Augsburg, 86159 Augsburg, Germany
Uwe Siart
Department of Electrical Engineering, School of Computation, Information and Technology, Technical University of Munich, 80290 Munich, Germany
Thomas F. Eibert
Department of Electrical Engineering, School of Computation, Information and Technology, Technical University of Munich, 80290 Munich, Germany
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Cited articles
Graf, M., Chwala, C., Polz, J., and Kunstmann, H.: Rainfall estimation from a German-wide commercial microwave link network: optimized processing and validation for 1 year of data, Hydrol. Earth Syst. Sci., 24, 2931–2950, https://doi.org/10.5194/hess-24-2931-2020, 2020. a
Leijnse, H., Uijlenhoet, R., and Stricker, J.: Microwave link rainfall estimation: Effects of link length and frequency, temporal sampling, power resolution, and wet antenna attenuation, Adv. Water Resour., 31, 1481–1493, https://doi.org/10.1016/j.advwatres.2008.03.004, 2008. a
Moroder, C., Siart, U., Chwala, C., and Kunstmann, H.: Microwave Instrument for Simultaneous Wet Antenna Attenuation and Precipitation Measurement, IEEE T. Instrum. Meas., 69, 5853–5861, https://doi.org/10.1109/TIM.2019.2961498, 2020. a
Overeem, A., Leijnse, H., van Leth, T. C., Bogerd, L., Priebe, J., Tricarico, D., Droste, A., and Uijlenhoet, R.: Tropical rainfall monitoring with commercial microwave links in Sri Lanka, Environ. Res. Lett., 16, 074058, https://doi.org/10.1088/1748-9326/ac0fa6, 2021. a
Pastorek, J., Fencl, M., Rieckermann, J., and Bareš, V.: Precipitation Estimates From Commercial Microwave Links: Practical Approaches to Wet-Antenna Correction, IEEE T. Geosci. Remote, 60, 1–9, https://doi.org/10.1109/TGRS.2021.3110004, 2022. a, b
Schleiss, M., Rieckermann, J., and Berne, A.: Quantification and Modeling of Wet-Antenna Attenuation for Commercial Microwave Links, IEEE Geosci. Remote S., 10, 1195–1199, https://doi.org/10.1109/LGRS.2012.2236074, 2013. a
Tiede, J., Chwala, C., and Siart, U.: New Insights Into the Dynamics of Wet Antenna Attenuation Based on In Situ Estimations Provided by the Dedicated Field Experiment ATTRRA2, IEEE Geosci. Remote S., 20, 1–5, https://doi.org/10.1109/LGRS.2023.3320755, 2023. a, b, c
Tiede, J., Chwala, C., Siart, U., and Eibert, T. F.: Supplementary Videos for Publication: J. Tiede et al., Frequency-Dependent Variations of the Antenna Reflection Coefficient Due to Different Wetness Conditions on the Antenna Radome, TIB AV-Portal [video], https://doi.org/10.5446/s_1877, 2025. a, b
Short summary
A hand sprayer is used to deposit droplets on the radome of an antenna. Before and during the drying process, measurements of the antenna reflection coefficient are performed repeatedly over time and frequency using a vector network analyzer. Continuous drifts from the wet state back to the initial dry state are demonstrated for individual antennas and frequency ranges. The obtained insights qualify the antenna reflection coefficient to be a promising indicator of momentary radome wetness.
A hand sprayer is used to deposit droplets on the radome of an antenna. Before and during the...
