SBIR-STTR Award

The primary goal of Phase I of this SBIR is an exploratory development to determine the instrument requirements needed to measure neutral winds in the upper atmosphere (90-300km) by passively measuring the Doppler shift of atomic oxygen airglow emission lines with a field-widened Doppler Asymmetric Spatial Heterodyne interferometer (DASH) instrument aboard a satellite platform in low Earth orbit. DASH interferometers are a new development of the optical technique of Spatial Heterodyne Spectroscopy (SHS) and offer the potential to provide low-power, light weight miniaturized instruments capable of wavelength resolutions required for measuring upper atmospheric winds to an accuracy of better than 20m/s through Doppler shift measurements. The conceptual flight design to be completed in Phase I will determine the mass, power, size and estimated cost of building a miniaturized DASH instrument to observe both the upper atmospheric green line and red line airglow emissions at 557.7nm and 630nm, covering the requirement altitude range of 90-300km. The secondary goal for Phase I is to complete a conceptual breadboard design for a ground-based DASH instrument to measure upper atmospheric winds. A breadboard design provides the basis for a Phase II SBIR where a DASH breadboard instrument would be built and fielded.

Keywords:
Neutral Winds, Shs, Miniaturized Interferometer, Passive Optical Instrument, Atmospheric Composition And Structure, Airglow, Space Weather, Small Satellite

This scope of this Phase II proposal is to develop a space flight prototype Doppler Asymmetric Spatial Heterodyne (DASH) spectrometer for the measurement of upper atmospheric winds.  A space flight prototype instrument will be built and tested to show DASH can successfully measure simulated Doppler winds in an environment similar to the environment it would be operating in on orbit.  This Phase II proposal builds on the recent laboratory demonstration that Spatial Heterodyne Spectrometers (SHS) can be modified to passively measure extremely small changes in wavelength from an emitting source (Englert et al, 2007).  DASH is a modified SHS and is a new type of Fourier transform spectrometer which requires no scanning mechanical components, can be built in a compact monolithic configuration, and maintain the same throughput as the best FTS instruments currently known.

Benefit:
There currently does not exist an operational satellite instrument, or ground-based instrument based capability to measure real time global atmospheric winds in the Mesosphere and Thermosphere.  The DoD recognizes the necessity of obtaining global upper atmospheric winds as an operational need for forecasting communications/navigation outages and for accurately predicting satellite drag affecting satellite orbits.  DASH holds the potential of being a low cost, compact, robust solution for obtaining global atmospheric winds from space.

Keywords:
Neutral Winds, Shs, Miniaturized Interferometer, Passive Optical Instrument, Atmospheric Composition And Structure, Airglow, Space Weather, Small Sate