[1] Space/Sequency Division Multiplexing
[2] Sub-rate Data Multiplexer
[3] Shut Down Mode (->"IEEE Standard Dictionary")
[4] Standardization Design Memorandum (->"IEEE Standard Dictionary")
[5] Statistical Delta Modulation (->"IEEE Standard Dictionary")
[6] Shuttle Data Management (->"NASA Acronym List")
[7] System Definition Manual (->"NASA Acronym List")
[8] San Diego-Brown Field, CA, USA -internationale Fughafen-Kennung