Three dimensional refraction-diffraction of EM waves through rocket exhaust plumes

The effects of a missile plume on radio communication with the missile are examined with a three-dimensional wave propagation model, R3D3. The model is formulated by combining plume and three-dimensional wave propagation models. The electron densities in the plume are calculated with account taken of resultant refraction and diffraction effects. Comparisons are presented of model predictions with experimental and MX missile flight test data. Refraction is found to have a minor role in the received signal strength, while alkali propellants cause diffraction similar to that around an opaque disk.