Pre-Hardware Optimization of Spacecraft Image Processing Algorithms and Hardware Implementation

1 Pages·2002·0.08 MB·English

by  Kizhner, Semion

Pre-Hardware Optimization of Spacecraft Image
Processing Software Algorithms and Hardware
Implementation
Semion Kizhner, David J. Petrick, Thomas P. Flatley, Phyllis Hestnes, Marit Jentoft-Nilsen
National Aeronautics and Space Administration
Abstract the PC environment, the necessity of RC
hardware implementation for bottleneck code
Spacecraft telemetry rates and telemetry product became more evident. The problem was solved
complexity have steadily increased over the last beginning with the methodology described in
decade presenting a problem for real-time [1], [2], and implementing a novel methodology
processing by ground facilities. This paper for this specific application. The PC-RC
proposes a solution to a related problem for the interface bandwidth problem for the class of
Geostationary Operational Environmental applications with moderate input-output data
Spacecraft (GOES-8) image data processing and rates but large intermediate multi-thread data
color picture generation application. Although streams has been addressed and mitigated. This
large super-computer facilities are the obvious opens a new class of satellite image processing
heritage solution, they are very costly, making it applications for bottleneck problems solution
imperative to seek a feasible alternative using RC technologies. The issue of a science
engineering solution at a fraction of the cost. The algorithm level of abstraction necessary for RC
proposed solution is based on a Personal hardware implementation is also described.
Computer (PC) platform and synergy of Selected Matlab functions already implemented
optimized software algorithms, and re- in hardware were investigated for their direct
configurable computing hardware (RC) applicability to the GOES-8 application with the
technologies, such as Field Programmable Gate intent to create a library of Matlab and IDL RC
Arrays (FPGA) and Digital Signal Processors functions for ongoing work. A complete class of
(DSP). It has been shown in [11 and [2] that this spacecraft image processing applications
approach can provide superior inexpensive development using re-configurable computing
performance for a chosen application on the technology to meet real-time requirements,
ground station or on-board a spacecraft. including methodology, performance results and
However, since RC technologies are still comparison with the existing system, is
maturing, intensive pre-hardware steps are described in this paper.
necessary to achieve the benefits of hardware
implementation. This paper describes these steps Table of Context
for the GOES-8 application - a software project
originally developed using the Interactive Data Abstract
Language (IDL) (Trademark of Research Introduction
Systems, Inc.) on a Workstation/UNIX platform. 1.0 Problem engineering complexity and
The solution involves converting the application solution methodology
to a PC/Windows/RC platform, selected mainly 2.0 Heritage application and its operations
by the availability of low cost, adaptable high- overview
speed RC hardware. In order for the application 3.0 Porting the UNIX/IDL application to the
to run on this PC/RC hybrid system, the IDL PC/Windows platform, modifying code,
software was modified to account for platform compilation and run
differences. It was interesting to examine the 4.0 Application performance timing
gains and losses in performance on the new methodology
platform, as well as unexpected observations 5.0 Timing tests on the PC/Windows98 platform
before implementing RC hardware. After 6.0 Algorithm definition, optimization and RC
substantial pre-hardware optimization steps in hardware implementation