USA-179 - ConclusionsThe two forms of transmission from USA-179 probably represent two pieces of equipment on the satellite. S-band may be the main payload or, more probably, it is command and control with the main payload operating in a different band entirely. USA-179 is a multi-tasking satellite and the VHF transmissions come from a payload that has its own radio transmission/reception requirements. The only other known current VHF payloads on an HEO are the AFSATCOM transmitters on 90025 and 90028 - the other two satellites in the same constellation. It is tempting to speculate that USA-179's VHF channels represent an alternative to AFSATCOM for some particular users. USA-179's near-rigid eight hour transmission schedule hints at a constellation of three satellites but, as yet, no HEO companions seem to exist. | |||||||||
