A Case Study in NASA-DoD - The Black Vault

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energy storage capacity as the STPSS, and (3) the communications system
is changed to be compatible with SGLS.
Listed below are the detail modifications to the MMS communication
module needed to achieve this compatibility. Again, these modifications
consist mainly of replacing MMS communication equipment with
STPSS equipment that performs a similar function. The necessary
changes to increase the data rate to 128-256 kbps have not been
considered as requirements.
SGLS Compatibility
a
Replace S-band transponder with STPSS S-band SGLS
transmitter and receiver.
* Replace or modify command decoder with STPSS decoder.
* Replace premod processor with STPSS dual baseband unit.
Increase Data Rate
* Replace data bus controller ) with STPSS bus
" Replace clock and format generator controller (data
* Replace standard computer interface formatter).
* Replace remote interface unit with STPSS data interface
unit.
Although the parallel battery-charging design used in the MMS
power module has been of some concern to the Air Force, it was not
considered necessary to change it (see Appendix B), since the power
regulation unit will have adequate redundancy to meet Air Force requirements,
and the MMS power system will be a flight-proven design
before the missions considered in this study are undertaken.
SPACE TEST PROGRAM MISSION MODEL
In accordance with the directions provided by the Work Statement
for this study, Space Test Program missions (26) to be flown during the
It should be noted that if the Air Force Solar Infrared Experiment
(SIRE) is flown on the MMS, these changes in the communication
module will have already been made before any of the missions considered
in this study. As noted later in this section, the MMS cost estimates
are based on this assumption, hence the nonrecurring cost associated
with these changes is not included in the study.