| Oceanic evaporation duct is an excellent natural channel for microwave communication, but microwave signals are easily affected by the air-sea environmental factors when propagating in the duct. In this paper, the Extended Fourier Amplitude Sensitivity Test is applied to examine the sensitivity of the microwave propagation path loss to environmental parameters including air temperature, sea surface temperature, near-surface wind, and relative humidity. The results show a frequency-dependent dispersion characteristic, while the signal polarization has little effect. Among the four environmental factors. relative humidity has the greatest impact on the path loss. Within
the area of short distance and high altitude, the wind speed dominates the propagation. The sensitivities of air temperature and sea surface temperature is roughly equivalent. The influence of wind speed is rather complicated and requires extra attention in the analysis. The sensitivity analysis results in this paper have important reference significance for the evaporation duct observation experiment. For the environmental parameters with high sensitivity, high spatial-temporal resolution observations can be given priority. In addition, when using mesoscale numerical weather prediction models for evaporation duct forecasting, priority is given to the development of parameterization schemes for physical processes related to air-sea parameters with high sensitivity, which can save computing time and resources. |
