A Microwave Spectral Emission Model for Rocket Plumes

Use of the microwave spectral region (10,000-100 micron) for DoD applications is largely unexplored, but offers significant advantages. For example, early detection of missile launches is key for missile defense. However, detecting launches using airborne and space-based sensors under all illumination and weather conditions is extremely challenging. The microwave region offers excellent cloud penetration and is not subject to solar illumination effects. A key reason for the lack of exploration of microwave sensing applications is the lack of a microwave plume signature model. Spectral Sciences, Inc. will address this need through an innovative microwave plume radiative-transfer model. In Phase I, we developed a prototype microwave/far-IR version of the DoD standard plume code, SPURC, and used it to perform a feasibility study of space-based microwave remote sensing of missile launches. In Phase II, we will finalize development of SPURC, integrate the microwave/far-IR approach into the widely used DoD scenario simulation model FLITES, extend the potential range of applications to other problems of military and commercial interest (e.g., chemical agent detection, atmospheric moisture profiling, hazardous chemical releases from factory smokestacks), and analyze plume field and laboratory flame data of microwave emissions. BENEFIT: The end product will be SPURC-MT (Microwave Terahertz), an accurate end-to-end model of plume signatures in the 30 GHz to 12THz (10,000 to 25 micron) spectral region. The software models will include all necessary parameter inputs and algorithmic capabilities to perform both internal combustion chamber, far-field plume simulations, and many other applications involving gas releases. The microwave to terahertz electro-optical regions encompass many potential applications, including combustion monitoring, trace gas species detection, investigation of interstellar media, and control of industrial chemical processes. Recent development of sources and detectors in this region has spurred great interest in this domain. The commercial value of SPURC-MT will be its ability to model the performance of the many sensor concepts being proposed and evaluated. SPURC-MT will be packaged as stand-alone code and as a set of add-on modules with well designed interfaces allowing easy integration into our own and other third party scenario simulation and analysis software.