Implementation of signal processing techniques in a space based scatterometer

E-Systems, ECI Division under contract from NASA JPL, has designed the scatterometer electronics subsystem (SES) component of the SeaWinds scatterometer. The scatterometer transmits a variable width MSK modulated pulse at a nominal pulse repetition interval (PRI) of 200 Hz. Two beams are transmitted spatially orthogonal to each other, and each beams return power is measured to determine wind speed and direction at the ocean surface. Designing for the harsh environment of space presents special difficulties. This paper describes the design implementation of the signal processing circuits in the SES, with reliability requirements for space as the major design driver. Issues discussed include parts selection (radiation, derating for space, power consumption, packaging), worst case analysis, radiation issues, and design architectures to mitigate the effects of random circuit disruptions.