Terrasat IBUC 3, Operation Manual

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IBUC
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, IBUC
3 G
Operations Manual: Functional Description
Engineered to Endure
Monitor and Control
Each IBUC is equipped with extensive monitor and control (M&C) capabilities. Such
capabilities can be accessed via:
• the M&C 19-pin circular connector J2 utilizing two-wire RS485. This method
requires that a separate cable be run and connected to J2.
• the J2 connector using RS232. This method requires that a separate cable be run
and connected to J2.
Figure G.1 on page G-2 contains a drawing for fabricating your own cable.
• the J4 connector using TCP/IP. This method requires a separate Ethernet cable.
Figure G.2 on page G-3 contains a drawing for fabricating your own cable.
• the L-band input N-connector or F-connector J1, utilizing Frequency Shift Keying
(FSK). Using this method requires no additional cables but does require that the
FSK be multiplexed onto the L-band cable.
Note:
Some modem manufacturers offer built-in FSK capabilities for communicating with
the IBUC through the L-band IFL. Refer to the modem manufacturer’s documentation
for more information.
RF Signal Flow
L - band input to the IBUC is through the J1 connector (Type N or Type F). Required
inputs include an L - band signal at - 20 dBm or less and a 10 MHz sine wave reference
signal b5 dBm and - 12 dBm (for those units that do not have the optional
internal 10 MHz reference signal).
The US National Institute of Standards and Technology defines single sideband (SSB)
phase noise as the ratio of the spectral power density measured at an offset frequency
from the carrier to the total power of the carrier signal. The phase noise unit of
measure most generally used has been the single sideband power within a one hertz
bandwidth at a frequency f away from the carrier referenced to the carrier frequency
power. This unit of measure is represented as L (f) in units of dBc/Hz. An internal
phase-locked Local Oscillator provides excellent phase noise when locked to an
external 10 MHz reference. Single sideband phase noise using an external reference
signal is listed in Table 2.3 .