Real-time data processing for an advanced imaging system using the Xilinx Virtex-5 FPGA

The multi-angle spectro-polarimetric imager (MSPI) is an advanced camera system under development at JPL for possible future consideration on a satellite based Aerosol-Cloud-Environment (ACE) mission as defined in the National Academies 2007 Decadal Survey. The MSPI project consists of three phases: Ground-MSPI, Air-MSPI, and Space-MSPI. Ground-MSPI is a ground-based 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. Lessons learned from the ground- and air-based demonstrations will be used in the design of the final satellite-based Space-MSPI instrument. In order to capture polarimetric data, the data collection algorithm oversamples the desired spatial resolution by a large factor. The actual polarimetric information can be efficiently extracted from this oversampled data. It has been proposed to do this extraction on the spacecraft for the purposes of reducing the total downlink data rate. As described in, the processing can be done in non-realtime on a Xilinx Virtex-4 FPGA. We have shown that this processing can be done in real-time on a Xilinx Virtex-5 FXT FPGA. Pseudo-random data simulating Ground-MSPI data stream is processed on the FPGA and the resulting polarimetric parameters are output using an Ethernet link to a host PC for verification. This demonstration is a stepping stone to an effective implementation for the Space-MSPI instrument.