Space Shuttle Tests Extra Terrestrial Fiber Optic Capabilities
The primary purpose of the coupler card was to provide attenuation and signal splitting between the HOST payload (a NASA Goddard experiment), and the shuttle's PGSC computer. The PGSC housed both the coupler card and a fiber optic transceiver card. The design provided an in-line means to monitor/troubleshoot the Fiber Optics Flight Experiment (FOFE) system without disconnecting cables/harnesses. During the transmission, the shuttle purposely flew through the South Atlantic Anomaly, part of the Van Allen radiation belt, to test the effect of high levels of radiation and electromagnetic interference on data transmission.
In future shuttle upgrades, fiber optic communication lines may be used in order to reduce weight and increase internal communication capability. Fiber optic lines will simplify data and communication interfaces and allow for more efficient payload processing and testing on the ground. Additionally, optical fibers are not susceptible to electromagnetic field such as those encountered in the Van Allen radiation belt.