Title: Real-Time On-Board Processing Validation of MSPI Ground Camera Images
Primary Author: Pingree, Paula
Organization: Jet Propulsion Lab
Co-Author(s): Thomas Werne and Dmitriy Bekker

The Earth Sciences Decadal Survey identifies a multiangle, multispectral, high-accuracy polarization imager as one requirement for the Aerosol-Cloud-Ecosystem (ACE) mission. JPL has been developing a Multiangle SpectroPolarimetric Imager (MSPI) as a candidate to fill this need. A key technology development needed for MSPI is on-board signal processing to calculate polarimetry data as imaged by each of the 9 cameras forming the instrument. With funding from NASA’s Advanced Information Systems Technology (AIST) Program, JPL is solving the real-time data processing requirements to demonstrate, for the first time, how signal data at 95 Mbytes/sec over 16-channels for each of the 9 multiangle cameras in the spaceborne instrument can be reduced on-board to 0.45 Mbytes/sec. This will produce the intensity and polarization data needed to characterize aerosol and cloud microphysical properties. Using the Xilinx Virtex-5 FPGA including PowerPC440 processors we have implemented a least squares fitting algorithm that extracts intensity and polarimetric parameters in real-time, thereby substantially reducing the image data volume for spacecraft downlink without loss of science information.

The MSPI project consists of three phases: Ground-MSPI, Air-MSPI, and Space-MSPI. Ground-MSPI is a ground-based camera demonstration focused on characterizing the imager optics and performance. Air-MSPI will be an updated version of the ground system to be flown on an ER-2 aircraft in 2010. Lessons learned from the ground- and air-based demonstrations will be used in the design of the satellite-based Space-MSPI instrument. We have developed a modular demonstration system to test and verify the real-time processing of the FPGA-based on-board processing system first with simulated data, then with ground camera input via a Camera Link interface, and finally with the AirMSPI camera system. Collaborative efforts continue with the AirMSPI development team to integrate the OBP solution with their FPGA design. At this time we will showcase the results of our real-time OBP validation of MSPI ground camera images using the Virtex-5 FPGA.