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Revision 10 8-22 450-SNUG
Table 8-7. TDRSS KaSA Return Service (cont’d)
Parameter (Note 4) Description (Note 4)
Reacquisition refer to paragraph 8.3.3.4
Orbital dynamics (free flight) 2
3
R 7.9 km/sec, R
11.4 m/sec , jerk .013 m/sec
Duty Factor 100 percent
Notes:
1. Operational considerations may limit choice of TDRS antenna polarization. The KaSA forward and return polarization must be the
same in order to obtain simultaneous forward and return services through the same TDRS SA antenna.
2. The BER is for a customer platform transmitting a signal on an AWGN channel which complies with the constraints defined in
Table 8-9. Refer to Appendix G for a discussion of the additional degradation applicable to the TDRSS KaSA return service
performance due to Ka-band RFI.
3. The required customer Prec must meet the Prec for BER, autotrack acquisition, or signal acquisition, whichever is greatest. Paragraph
8.3.3.2.b provides the required Prec description for each possible KaSAR data configuration. Refer to Appendix A, paragraph A.4, for a
definition of Prec. The minimum required Prec equations for BER produce the minimum Prec for a given data rate for all possible signal
characteristics. CLASS analysis will produce a more accurate performance projection based upon desired customer signal
characteristics, such as data rate, data type, and jitter values. SN support may be possible for customers whose Prec is less than the
required Prec for 10 -5 BER performance; however, such support shall be coordinated through GSFC Code 450.
4. All data rate values (and notes which modify these values, based upon specific signal format and encoding restrictions) are to be
interpreted as data bit rates, and not as data symbol rates.
5. For acquisition, the minimum Prec value listed applies to the total (I+Q)Prec. Acquisition requires the Prec to also be consistent with
the Prec required for BER, whichever is greater. Failure to provide the minimum P
rec
for autotrack acquisition at the start of service
may preclude successful TDRSS autotrack pull-in.