The communications subsystem provides voice communications
through 1,000-watt single sideband HF transmitters and receivers as well as a 200-watt UHF
satellite terminal, and data retransmission through a 1,000-watt UHF satellite terminal.
Voice communications provide a link between the deployed aircraft and the ARIA Operations
Control Center (AOCC) at Edwards Air Force Base, California, for flight-following and mission update
during aircraft deployments. Data retransmission to the launch agency via satellite allows
instantaneous analysis of critical events onboard the spacecraft. The ARIA uses the FLTSAT
(Navy fleet satellites), LEASAT (leased satellites), LES (Lincoln experimental satellites)
and UFO (UHF follow-on satellites) satellite systems during satellite voice communications
and data retransmission.
Satellite Data
Retransmission
Narrowband data may be unlinked to a UHF communications
satellite for real-time monitoring at a ground station. Data bandwidth is limited by
ability and priority for scheduling satellite time. Typically, maximum allowable satellite
bandwidth is 25 kHz, but occasionally a very high priority mission may enable a bandwidth
of 50 kHz or more.
Secure SATCOM
Voice communications may be relayed through UHF satellites
on ARIA which are so equipped (eventually, all ARIA). The T-R unit is capable of plain or
cipher text voice or data, in satellite or line-of-site mode.
Voice/Data Encrypter
The SUNBURST II processor enables the T-R to operate in
secure modes compatible with several types of existing COMSEC equipment.
HF Voice
Communications
Three receiver/transmitter sets comprise the system for HF
mission communications. Two separate full duplex links (three over water using the
trailing wire antenna) may be used at one time. This system is separate from the flight
crew HF radios.
Audio Processing
Internally and externally generated audio signals can be
routed through several different systems, depending on mission requirements.
Interphone
Each crew station provides interphone capabilities to
allow operators to communicate with other crewmembers or external parties with appropriate
patching by the communications operator. The AIC-18 interphone system is divided into two
loops - aircraft and PMEE - but the two can be interconnected. The PMEE loop capabilities
have been expanded by the addition of a 376R-19 control indicator at the mission
commander's station and a 376R-21 control indicator at the communications operator's
station. Pushbutton switches in these units allow the respective operator to establish
additional unique interphone circuits.
HF Audio Control
The HF audio control, Collins model 376R-18, allows the
operator to select each individual HF sideband audio signal and route it to any of several
aircraft interphone circuits via a pushbutton matrix. A separate control is provided for
each transmitter/receiver.
Spacecraft Audio
Control
The spacecraft audio control, Collins model 376R-17, was
originally used for Apollo spacecraft audio distribution. It is now used only to enable
mission crew control of the transmit audio and key lines for the flight crew UHF radios to
facilitate an auto-relay. Visit the RCC/FTS section for more information on UHF relay.
Audio Patch Panel
The audio patch panel, Collins model 256Z-1, allows the
operator to manually interface the HF, UHF, SATCOM, and aircraft interphone audio circuits
in nonstandard configurations. It also provides an audio oscillator, dBm meter, and test
points for testing and calibration of T/R and interphone audio circuits and squelch
controls.
