Parabolic equation modelling of the effects of multipath and ducting on radar systems

The parabolic equation approach to the modelling of clear-air propagation, and in particular to the assessment of radar performance in the presence of multipath and ducting, is described. The derivation and solution of the parabolic equation by means of the split-step algorithm are described. A discussion of the radar equation is given to provide a connection with conventional assessment methods. The model is applied to the problem of anomalous propagation and the influence of the ground. One of the main advantages of the parabolic equation approach over alternative ray and mode methods is its ability to make quantitative predictions for two-dimensional refractive-index structures without the need for a priori identification of the structures. New applications, such as wideband effects and the influence of refractive-index fluctuations and measurement errors on prediction accuracy, are discussed. Clutter modelling and other extensions to the model are briefly mentioned