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Table 7-11. TDRS KuSAR IF Service Spacecraft and Ground Segment Channel
Characteristics (cont’d)
Notes:
1. The customer should schedule the TDRS receive center frequency to the KuSAR TDRS receive
center frequency, where the TDRS receive center frequency will be translated to the center of the IF
bandwidth. The signal and carrier frequency will be constrained such that the first null of the
spectrum falls between 14.8834 and 15.1234 GHz. The KuSAR IF service only supports noncoherent
frequencies. The KuSAR IF service supports only one Ku frequency through one TDRS at
a time. These frequencies do not include the effects of Doppler shift. The KuSAR IF service is not
required to provide a Doppler-corrected IF output signal. The customer provided receiver needs to
handle Doppler.
2. Constraint parameters are contributions from the TDRS spacecraft and the SN ground segment to
the IF interface. Not included in these aggregate distortion amounts are TDRS spacecraft gain
flatness, linear and parabolic allowances, and phase nonlinearity parabolic and cubic allowances as
described in 405-TDRS-RP-SY-001, WU-02-01, and SY1-89E. Customer and receiver signal
characteristics need to be considered to determine the end-to-end performance. Please contact
GSFC Code 450 for further information.
3. The 3 dB RF bandwidth is larger than the specified 225 MHz bandwidth value specified in Table 7-7.
This value has validated through spacecraft and ground terminal measurements, but may not be
applicable to future TDRS.
Table 7-12. Potential TDRSS KuSA IF Return Service Configurations (Customer
interfaces with the SN at a 370 MHz IF and Customer provides the Receiver)
BPSK
QPSK /
SQPSK
8PSK
Return IF Service Configuration
(notes 1, 2)
Potential Maximum Data Rates
(IF Service)
Rate 1/2 convolutional coded See Table 7-6
Uncoded See Table 7-6
Rate 1/2 convolutional coded See Table 7-6
Uncoded See Table 7-6
(128,120)x(128,120) TPC (note 3) 400 Mbps
(8176,7136) LDPCC (notes 3, 4) 400 Mbps
(2048, 1024) AR4JA LDPCC 200 Mbps
(128,120)x(128,120) TPC (note 3) 600 Mbps
(8176,7136) LDPCC (notes 3, 4) 600 Mbps
Uncoded 450 Mbps
Notes:
1. All data rates assume NRZ data format.
2. These service configurations and maximum data rates were based upon simulation
results only and have not been verified by testing. Other data rates and modulation
schemes may be possible. Please contact GSFC Code 450 for further information.
3. For the IF service, data rates up to 410 Mbps may be possible for QPSK/SQPSK
modulation with either TPC or (8176, 7136) LDPCC. For the 225 MHz IF service, data
rates up to 625 Mbps may be possible for 8PSK with either TPC or (8176,7136)
LDPCC. Please contact GSFC Code 450 for further information.
4. The code being supported is the (8160, 7136), the shortened version of the (8176,
7136) code.
Revision 10 7-48 450-SNUG