Radar-based Investigation of Electromagnetic Waves Under Different Temperature and Humidity Conditions

This paper presents investigations of the influence of temperature and humidity variations on electromagnetic signals within the frequency range of 68 GHz to 92 GHz. Assuming the environmental air acts as a frequency-dependent dielectric material, the propagation of electromagnetic waves depends on the thermal and molecular composition, and consequently, influences the measured phase. Two main scenarios are explored: varying temperature at constant relative humidity and varying relative humidity at constant temperature. Experimental data is collected using an W -band radar system within a controlled environment of a climate chamber. They validate theoretical models, providing insight about the relationship between temperature, humidity, and phase differentials. The conclusive measurements reveal that phase variations induced by fluctuations in air temperature and humidity are detectable.