Performance; Table 1-1. Acquisition And Timing Performance Requirements; Table 1-2. Doppler Requirements - Comtech EF Data SLM-5650A Installation And Operation Manual

SLM-5650A Satellite Modem
Introduction
1.4.1

Performance

1.4.1.1 Acquisition and Timing Performance Requirements
The following reference E
with Reed-Solomon FEC not enabled.

Table 1-1. Acquisition and Timing Performance Requirements

Parameter
Initial Acquisition
Reacquisition
BCI
System Retention
Receive Timing Jitter
Doppler
Parameter
Doppler Shift in Hz
Doppler Rate of Change in Hz/sec
Doppler Acceleration in Hz/sec
/N is defined as the required E
b 0
Specification
The modem achieves initial acquisition within the times as specified within ± 30 kHz at
the reference E /N
b 0
For baseband data rates between 64 kbps and ≤ 128 kbps, the maximum
•
initial acquisition time is 500 seconds.
For Baseband data rates between 128kbps and ≤ 1544 kbps, the maximum
•
initial acquisition time is 30 seconds.
For baseband data rates > 1544 kbps, the maximum initial acquisition time is
•
1.5 seconds.
Reacquisition is achieved, as follows, after a period of up to 15 minutes of the absence
of signal when the carrier returns to within 500 Hz of its original frequency.
For baseband data rates between 64 kbps and 128 kbps, the maximum
•
reacquisition time shall be 45 seconds.
For baseband data rates between 128 kbps and 1544 kbps, the maximum
•
reacquisition time shall be 20 seconds.
For baseband data rates greater than 1544 kbps, the maximum reacquisition
•
time shall be 1 second.
With Tx and Rx random data, the mean time to loss of BCI due to falsely adding or
deleting bits is at least 3 days at the reference E
BCI over 50 consecutive bits of all ones or zeros, which occur no more than once in
10,000 bits, without employing data scrambling.
Synchronization and BCI are maintained for all E
(BPSK/QPSK/OQPSK/8PSK) for signal loss of up to 50 modulation symbol periods, with
a probability of at least 90 percent.
The Rx output clock peak timing jitter cannot exceed ± 5 percent at the reference E
when the modulated signal meets the modulation timing jitter requirement.
The modem meets the requirements with a Doppler shift, rate of change, and
acceleration for satellite inclination up to ± 7° as presented in Table 1-2, and an
additional 0.5 dB added to the reference E

Table 1-2. Doppler Requirements

C-Band
± 2475
± 226
± 243
2
1–14
MN-SLM5650AMN-SLM5650A
/N corresponding to a BER of IE-3
b 0
/N . In addition, the modem maintains
b 0
/N above the reference E
b 0
/N .
b 0
X-Band Ku-Band
± 3535 ± 6045
± 270 ± 490
± 290 ± 526
Revision 8
/N
b 0
/N
b 0
Ka-Band
± 11,810
± 1046
± 1124