Time-Delay Integration Imaging with ICON's Far-Ultraviolet Imager.

Area of Science:

• Space Physics
• Remote Sensing
• Instrument Development

Background:

• Earth's ionosphere emits Far Ultraviolet (FUV) light, particularly at 135.6 nm, providing insights into atmospheric dynamics.
• Observing these emissions from Low Earth Orbit (LEO) requires sophisticated imaging systems to compensate for spacecraft motion and optical distortions.

Purpose of the Study:

• To develop and present a Time-Delay Integration (TDI) image processing system for the ICON mission's FUV Spectrographic Imager.
• To enable motion-compensated imaging of Earth's nightside ionospheric limb and sub-limb.
• To provide corrections for optical distortions inherent in the FUV Imager's optics.

Main Methods:

• Designed a TDI system as a Field-Programmable Gate Array (FPGA) module.
• Implemented variable-range motion compensation for LEO observations.
• Integrated optical distortion correction capabilities.
• Developed processing for simultaneous 135.6 nm and 157.0 nm wavelength altitude profiles for dayside observations.

Main Results:

• The TDI system successfully compensates for motion and corrects optical distortions.
• Demonstrated simultaneous processing of multiple FUV wavelengths.
• Achieved minimization of on-board data throughput and telemetry, crucial for space missions.
• Validated system performance through simulation and Engineering Ground Support Equipment (EGSE) testing.

Conclusions:

• The developed TDI system is a robust solution for enhancing FUV imaging of the ionosphere.
• The FPGA implementation offers an efficient and effective approach for on-board data processing.
• The system meets the mission requirements for high-quality ionospheric observations from LEO.