Atmospheric models for over-ocean propagation loss

Humidity over the ocean tends to be higher than over land, and long-range links at frequencies above 10 GHz may experience large propagation loss due to atmospheric absorption. When high link reliability is required, the log-normal assumption used to estimate power margins from the loss mean and standard deviation is not accurate. To solve these problems, a set of atmospheric models has been developed from radiosonde profiles collected along the Atlantic coast of the US. The large quantity of radiosonde data available was used to identify radiosonde profiles that occur with specified probabilities at different times of year and locations. The result was used to estimate high-reliability SHF/EHF air-to-surface radio link performance in a maritime environment.