The Seasat Low Rate Data Processing System

SEASAT was a proof of concept mission designed to demonstrate techniques for the global monitoring of oceanographic phenomena by satellite remote sensing. Included in the techniques to be demon- strated were the ability to develop algorithms to produce geophysically useful measurements from the satellite data, and to distribute data to users in a timely manner. The ground data system which supported these objectives for the low rate sensors (that is, excluding the Synthetic Aperture Radar) included subsystems for the acquisition and pre-processing of telemetry; calculation of orbit and attitude data; decommutation, engineering unit conversion, and earth location of the measurements; instrument calibration; calculation of geophysical observables; data cataloging, and data distribution. This system provided data to sensor managers and experiment teams, allowing verification of sensor performance, refinement of processing algorithms, and distribution of processed data with known quality to the scientific user community.