Comtech EF Data SDM-309B - Manual (Page 110)

SDM-309B Satellite Modem M&C and Interfaces
MN/U-SDM309B Rev. # 4-4–33
Satellite Data Rates Supported N x 64 Kb/s,
N = 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20 r 24
(T1)
N = 1, 2, 3, 4, 5, 6, 8, 10, 12, 15, 16, 20, 24,
or 30 (E1)
N = 32 (E1_IBS)
N = 24+ (T1_IBS)
Satellite Overhead Rate 1/16 of Data Rate
per IESS-308 Rev. 6 and IESS-309 Rev. 3
Drop Time Slot Selection
(Time Slot 0 not allowed) 1 to 24 (T1)
1 to 31 (E1)
Arbitrary Order
Insert Time Slot Selection
(Time Slot 0 not allowed) 1 to 24 (T1)
1 to 31 (E1)
Arbitrary Order
Interface Type Transformer Coupled Symmetrical Pair
Data Rate T1 1544 Kb/s ± 100 b/s
E1 2048 Kb/s ± 130 b/6s
Pulse Width T1 324 ± 50 nsec
E1 244 ± 25 nsec
SD Amplitude T1 3.0 + 0.3/- 1.5 V pk into 100
!
E1 3.0 + 0.3/- 1.5 V pk into 120
!
RD Amplitude T1 3.0 ± 0.3 V pk into 100
!
E1 3.0 ± 0.3 V pk into 120
!
Pulse Mask T1 G.703.2
E1 G.703.6
Line Code Selectable AMI, B8ZS, HDB3
Jitter Attenuation T1, per AT&T 43802
T1, per CCITT G.824
E1, per CCITT G.823
Transmit Clock Reference Normal (derived from Drop SD)
Internal (10-5 accuracy)
External (RS-422 Input)
Plesiochronous Buffer Included in receive path
Buffer Clock Reference Derived from Insert Input
External (RS-422)
Internal
Buffer Depth
T1, T1_ESF, E1_CCS,
E1_IBS, E1_31_TS
1, 2, 4, 6, 8, 12,
24, or 32 msec
E1_CAS 7.5, 15, 30 msec
T1_IBS 6, 12, 18, 24 or 30 msec
Depth Status Monitored accurate to 1 %
Buffer Centering Automatic (start of service)
Manual
Overflows/Underflows Logged as stored fault
ESC Data Interface Type RS-232
ESC Data Rate 1/2000 of Satellite Data Rate,
Maximum (Oversampled)
ESC Data Circuits Supported SD, RD, DSR
Backward Alarms Supported 1, looped per IESS-309
Backward Alarm Output Sums into Secondary Alarm
Modulator Fault Open collector, 15 V max,
20 ma max. Used by Protection switch if in
System
Demodulator Fault Open collector, 15 V max,
20 ma max. Used by Protection switch if in
System