Unique Model of Plume RF Signatures for Missile Detection, Identification, Characterization, and Tracking

To provide the MDA with new space-borne intelligence-gathering passive-sensing techniques for the detection, identification, characterization, and tracking (DICT) of hostile ballistic and cruise missiles and other advanced systems, we are expanding our unique physical models that allow for the interpretation of radio frequency (RF) signatures of missile plumes in a way that is directly traceable to the radiating source. The signature is the result of both thermal and nonthermal radiation. The latter is defined by electric charge separation and acceleration. The usual thermal radiation theory must be expanded to include electric charge separation in hot, ionized combustion gases in order to calculate accurately the electrical conductivity within the plume and, therefore the absorption/transmission of the radiation from the plume. The output of any appropriate quasi-steady plume flow field computer code becomes the input to our post-processor 3-dimensional radiation code RFPLUME. Previously, we applied the theoretical model of nonthermal RF radiation to that from axisymmetric quasi-steady plumes in the upper atmosphere and also to that from an unsteady plume impacting the launch pad. This work will now be extended and generalized to 3D flows resulting from multiple rocket nozzles and/or oblique interactions with the launch pad. More realistic missile configurations, more ionized species, and more sophisticate equations of state of the combustion products will be considered.