Imaging Sensor Constellation for Tomographic Chemical Plume Mapping

In this SBIR effort Physical Sciences Inc (PSI) has proposed to develop a sensor constellation that can be used to determine the size (length, width, and height), location, and detailed concentration distribution of chemical agent simulant clouds released on test ranges. The system proposed by PSI will be capable of imaging in the 8-11 micron region with a spectral resolution of 8-10 cm-1, and an NESR of 1-2 µW cm-2 sr-1 µm-1. The system will be capable of detecting the chemical cloud from a standoff distance of 1.5 km, and to beyond 300 m downwind of the plume release point with a spatial resolution of 6 meters per pixel. The sensor constellation is based on the use of standoff passive multispectral infrared imaging to make simulant column density measurements through the chemical cloud from two or more locations around its periphery. A Computed Tomography (CT) inversion method will be employed to produce a three dimensional concentration profile of the cloud from the line density measurements. The system will also be able to determine the boundaries of the cloud (length, width, and height) from the concentration profile data. This information will be presented in real-time to the end-user.