NPOESS VIIRS design process

This paper presents an overview of the Visible and Infrared Imaging Radiometer Suite (VIIRS) design process that achieved exceptional competitive IPO ratings for system optimization, sensor system design, and systems engineering, integration and test (SEIT). A novel aspect of the competition was provision to the sensor competitors of a specification of geophysical measurement requirements called "Environmental Data Records" (EDRs), rather than a sensor hardware specification. The contractors were required to derive optimal VIIRS hardware specifications from the EDRs, and Raytheon's process is the subject of this paper. VIIRS will become the next-generation United States polar-orbiting operational environmental imaging radiometer, with the first launch scheduled for 2005 aboard the National Polar-orbiting Operational Environmental Satellite System (NPOESS) Preparatory Project (NPP) spacecraft. Beginning in 2008, the NPOESS VIIRS instrument will be launched into 1330, 1730, and 2130 local-time ascending-node sun-synchronous polar orbits as the single operational source for dozens of civil and defense environmental and weather products(1), as well as climate research data(2). VIIRS will replace three different currently operating sensors: the Defense Meteorological Satellite Program (DMSP) Operational Line-scan System (OLS), the NOAA Polar-orbiting Operational Environmental Satellite (POES) Advanced Very High Resolution Radiometer (AVHRR), and the NASA Earth Observing System (EOS Terra and Aqua) MODerate-resolution Imaging Spectroradiometer (MODIS)(3). A critical VIIRS challenge was design optimization to differing requirements from the three user agencies (DoD, NOAA, and NASA) represented by the NPOESS Integrated Program Office(4).