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7.1.3 Customer Acquisition Requirements
Acquisition and reacquisition by the customer platform of the TDRS transmitted signal
requires prediction by the customer MOC of the customer platform receive frequency
over various projected time periods. Similarly, acquisition and reacquisition by the SN
ground terminal of the customer platform signal requires prediction by the customer
MOC of the customer platform transmitter frequency over various projected time
periods. The frequency predictions are ultimately incorporated in the SHO as customer
platform frequencies for the specific service support periods. Refer to Section 9 for
additional information on TDRSS tracking services that can assist customers in
predicting their local oscillator frequencies.
7.1.4 TDRSS Acquisition Support to Customers
For each scheduled TDRSS service support period, the customer requirements for
signal acquisition/reacquisition, and the TDRSS capabilities to aid acquisition/
reacquisition, are as follows:
a. Customer Epoch Uncertainty
1. Autotrack. The maximum epoch time uncertainty of the applicable
customer platform ephemeris supplied to the TDRSS shall be +4.5
seconds and +3.2 seconds for customer platform operations requiring the
TDRSS KuSA return service autotrack process within the TDRSS Primary
FOV and EEFOV, respectively. Similarly, the maximum epoch time
uncertainty of the customer platform ephemeris shall be 4.5 seconds for
the TDRSS KuSA return service autotrack process within the TDRSS
LEOFOV.
NOTE:
KuSAF EEFOV autotrack support and KuSAR EEFOV
autotrack support shall be coordinated through GSFC Code
450. Autotrack service is not available through the Ku-band
return IF service.
2. Program track. The maximum epoch time uncertainty of the applicable
customer platform ephemeris supplied to the TDRSS shall be +4.5
seconds and +3.2 seconds for customer platform operations using TDRSS
KuSA open-loop pointing within the TDRSS Primary FOV and EEFOV,
respectively.
3. LEO Program track. The maximum epoch time uncertainty of the
applicable customer platform ephemeris supplied to the TDRSS shall be
+1.5 seconds for customer platform operations requiring the TDRSS KuSA
open-loop pointing for customers within the TDRSS LEOFOV.
b. Customer Frequency Uncertainty. The customer MOC must know the
operating frequency of the customer platform to within +5 kHz.
Revision 10 7-2 450-SNUG