SPACE-FLIGHT DIGITAL SIGNAL PROCESSOR SYSTEM FOR ON-BOARD PROCESSING OF EXPERIMENT DATA

We have developed a digital signal processor (DSP) system to extend th e capabilities of a variety of scientific instruments used to make in situ ionospheric plasma measurements from sounding rockets and spacecr aft. The DSP system is extremely flexible due to the use of a field pr ogrammable gate array, sigma-delta analog-to-digital converters, and a highly integrated single-chip DSP. Using virtually identical circuitr y, we have operated DSP systems processing data from low-frequency ele ctric field detectors, Langmuir probes, and several radio-frequency re ceivers on several sounding rockets and spacecraft with different digi tal telemetry interfaces. The DSP system provides three major improvem ents to our instruments: (1) reduced telemetry bandwidth (data) requir ements, (2) improved signal-to-noise ratio, and (3) digital antialiasi ng filtering. We describe our DSP system and show three examples of ho w we have implemented it with our instruments. Similar systems should be of interest to researchers in many fields of research.