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This Defense Intelligence Reference Document from the Defense Intelligence Agency, dated 1 November 2010, was produced under the Advanced Aerospace Weapon System Applications (AAWSA) Program. It describes nanosatellite technologies and proposes launching nanosats into orbit with laser Lightcraft propulsion. It also covers a weapon mission selection study and multi-megawatt laser options. The author recommends that the Department of Defense and NASA bring Lightcraft R&D back to the United States and restart the X-50LR flight demonstration program.
“The Advance”13 pages
UNCLASSIFIED/ /f81il 8ffl@IAI!: 1!181! 8••1::Y Because configuration (2) has a much smaller overall energy balance than configuration (1), it is much more sensitive to MLI properties and to internal power dissipation. However, eclipse performance improves. During the ~ 8 hour eclipse, internal temperatures drop by only 20°C, a marked improvement, with end-of-eclipse temperatures well within the range of most spacecraft components. It should be noted that the solar arrays, since they are now isolated from the body of the nanosat, drop to temperatures of about -1l0°C. Even these solar array temperatures should not pose a problem. For example, the solar arrays of many geosynchronous satellites drop routinely to temperatures of about -150°C during the 72 minute eclipse experienced by these spacecraft at each equinox season. The key feature of configuration (3) is that the equipment is coupled to an external radiator only with a two-phase heat transport device, such as a capillary pumped loop (CPL) or loop heat pipe (LHP). Operational temperatures are again maintained to temperatures of about 20°C nominal with a properly sized radiator. However, the temperature is also totally dependent on the proper operation of the two-phase "loop." The two-phase heat transport device can be made redundant by the addition of a second loop if single fault tolerance is desired. Note that redundancy is not a consideration for the other two configurations. During the ~ 8 hour eclipse, further improvement is realized, with internal temperatures dropping by as little as 6°C if the internal payload is well insulated from the exterior of the nanosat. As in configuration (2), the solar array temperatures drop to about -110°C. For certain equipment or science instruments, the temperature control afforded by this type of "active" design may be necessary. A moderate amount of technology development has been underway since 2000 to enable a two-phase heat transport system for use in a nanosat. The small size and low heat transport requirements of the nanosat will necessitate significant downsizing of today's flight qualified two-phase systems. This reduction will be accomplished by leveraging recent successful tests of a small cryogenic two-phase CPL. RF COMMUNICATIONS The onboard RF subsystem must be small, low mass, and low power. The system specifications are: • Mass: 0.5 kg. • Power consumption: 0.5 watt. • Transmission data rate: up to 100 kbits/sec. • Command reception data rate: 1 kbit/sec. • Range: 3 to 5 Earth radii. • Channel type: BPSK. • Effective isotropic radiated power: 0.15 watt (-8.2 dbW). • Carrier frequency: 8,470 MHz. The tracking system should be coupled with this communication subsystem to maximize efficiency in mass and power. 7 UNCLASSIFIED/ /f81il 8FFI&I.«1k WEE 0111 Y
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 77 pages are in the text index: search them above, or from the library's search.