Influence of atmospheric propagation effects on holographic imaging techniques

The paper assesses the influence of atmospheric propagation effects on holographic imaging with microwaves. Attention is focused on the inherent limitations of an ideal system in free space without consideration of atmospheric influences, and to atmospheric influences on coherence degradation and attenuation due to the refractive index structure, including fog and precipitation. It is shown that holographic imaging with real apertures, especially for millimeter waves, could be of interest for short range applications under conditions of bad visibility, where optical and infrared systems fail. It seems that decorrelation effects due to the turbulent clear atmosphere can be neglected in most cases. Whether this conclusion is also true in the presence of dense fog or rain is not certain and requires further investigation.