How does the IMAGE satellite collect and transmit data to the ground?

The Central Instrument Data Processor (CIDP) onboard the satellite will handle routing commands from the ground to the various instruments, receive streams of data from each instrument, and format and transfer this data to the spacecraft's telemetry system at a rate of 2.2 megabits/sec from a mass memory 'buffer'. The scientific instruments will produce a variety of binary 'bit streams' at a total rate of 26,000 bits/sec. There will also be about 2,000 bits/sec of spacecraft 'housekeeping data'. This data cannot be telemetered to a ground station until a scheduled time of the day, so the data has to be cashed in a 2 billion bit bulk memory 'buffer'. The expected actual data will account for 1.78 billion bits, and at a telemetry rate of 2.2 megabits/sec, it will take about 13.5 minutes for the ground station to receive the previous day's data.

The Jet Propulsion Laboratories 'Deep Space' tracking network will make contact with the satellite, and the data will be recorded, and then relayed to the Science and Mission Operations Center at the Goddard Space Flight Center via a satellite link.

For more on the CIDP, visit the IMAGE Preliminary Design Review report which discusses it in more technical detail.


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