Timely prediction of low-altitude radar performance in operational environments using in situ atmospheric refractivity data

A shipboard radar decision aid that may be used to predict low-altitude radar performance and assist the radar operator in maximising system capabilities in the existing propagation environment is discussed. The system, developed for use aboard US Navy AEGIS-class ships, uses expendable rocketborne radiosondes to make high-resolution measurements of the atmosphere. A version of the Johns Hopkins University Applied Physics Laboratory´s electromagnetic parabolic equation (EMPE) propagation model is used to calculate the effects of the measured refractivity environment on the propagation of energy radiated by the radar. A radar model uses these data in predictions of the system´s low-altitude target detection capabilities. The effects of many radar operator controllable options on target detectability may be evaluated in the propagation environment with this system. A significant portion of the data acquisition-to-display process has been automated. Design and implementation of this system and results of at-sea testing are discussed