End-to-end data flow on the Soil Moisture Active Passive (SMAP) mission

The Soil Moisture Active Passive (SMAP) satellite mission will provide measurements of the soil moisture and freeze/thaw state over the Earth's land surface, significantly enhancing knowledge of the Earth's water, energy, and carbon cycles. Collecting, transmitting, processing, and archiving the complete set of science and engineering data will be a major challenge. SMAP will fly a radiometer and a synthetic aperture radar, collecting data over the land and ocean, based on science requirements. The Command and Data Handling subsystem will then select and packetize data for downlink on multiple transmission links. The data will generate nearly 250 GBytes of distributable data products on a daily basis, most of which need to be generated and made available to scientists within 24 hours of acquisition. SMAP instrument hardware, ground software, and mission planning will incorporate design and operational mechanisms to reduce data loss from sources such as radio frequency interference.