The FWMI prototype development is underway at USU/SDL. To develop the FWMI, USU/SDL is leveraging the successful implementation of a rocket-borne Michelson interferometer/spectrometer system that was designed by USU/SDL in the early 1980s and flown multiple times on sounding rockets. This sensor was designated the Rocket-Borne Field-Widened Interferometer-II (RBFWI-2). Utilizing modern designs, technologies, and components, the new prototype FWMI will significantly enhance the original RBFWI-2 to meet three technical goals: (1) extended spectral coverage, (2) higher spectral resolution, and (3) extended dynamical range. USU/SDL also intends to achieve large reductions in mass, volume, and power. The resultant prototype FWMI will then be a pathfinder for future missions that focus on addressing key scientific objectives and critical supporting science questions in auroral ionosphere-thermosphere energetics.
The successful flight of RBFWI-2 established a solid foundation for the development of the prototype FWMI. Based on that heritage, the current effort focuses on the development of a new optical detector system, a new sensor signal-conditioning system based on modern electronics, as well as extending the displacement of the optics to increase spectral resolution. These new techniques and other modern technologies will be added to the proven RBFWI-2 legacy design to allow the prototype FWMI to serve as the foundation for a flight FWMI version capable of meeting the targeted instrument specifications that are summarized below:
1. Spectral bandpass of 1300-8100 cm-1
2. Spectral resolution of ≤ 1.0 cm-1
3. Dynamic range characterized by a 10-13 W cm-2 sr-1(cm-1)-1 NER.