THE EFFECTS OF ATMOSPHERIC CIRCULATION ON LINE-OF-SIGHT MICROWAVE LINKS

This paper presents an investigation of a lake-land breeze atmospheric circulation responsible for strong horizontal and vertical inhomogene ities of moisture distribution which affected the refractivity in the neighborhood of a microwave line-of-sight link, as observed during a m ulti-instrument radiometeorological experiment carried out in Sao Paul o, Brazil. A boundary layer and mesoscale atmospheric model was used t o simulate the local circulation within the link region and to compute the time evolution of the vertical structure of the atmospheric refra ctive index. A ray-tracing model was also used to calculate the intens ity of the received signals from the measured refractive index vertica l profiles. The integrated simulation results were then compared with the measurements. The good agreement obtained between the measured and the simulated characteristics of the temperature and moisture advecti on, as well as between the measured and the calculated received signal levels, indicates that the lake-land breeze circulation mechanism is a likely source of the propagation phenomena observed in the microwave link.