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Appendix E. Customer Platform and TDRS Signal Parameter
Definitions
E.1 General
This Appendix defines the salient characteristics of the TDRSS forward service to a
customer platform and the parameters which constrain the customer platform
transmitted signal. The specifications of these parameters are given in Tables 5-3
(MAF), 6-4 (SSAF), 7-3 (KuSAF), 8-3 (KaSAF), 5-11 (MAR), 6-12 (SSAR), 7-9
(KuSAR), and 8-9 (KaSAR), respectively.
E.2 Symbol (Data) Asymmetry
a. For the NRZ signal format, symbol (data) asymmetry is defined as follows:
length of long symbol - length of short symbol
length of long symbol + length of short symbol
100%
b. For the Biphase format signal (S-band DG2 only), data asymmetry applies to
both the entire symbol and to each half-symbol pulse. Therefore, for Biphase,
symbol (data) asymmetry is defined as follows:
1. For the entire symbol:
length of long symbol - length of short symbol
length of long symbol + length of short symbol
2. For the half-symbol pulse:
100%
length of long half symbol pulse - length of short half symbol pulse
length of long half symbol pulse + length of short half symbol pulse
100%
E.3 Symbol (Data) Rise Time
Symbol (data) rise time is the time required to switch from 90 percent of the initial data
state to 90 percent of the final data state as a percentage of symbol duration. Symbol
(data) rise time is illustrated in Figure E-1.
1
.9
0
-.9
-1
INITIAL
STEADY
STATE
DATA
TRANSITION
TIME
FINAL STEADY STATE
Revision 10 E-1 450-SNUG