E.6 frame formats – Comtech EF Data CDM-625A User Manual
Page 597
CDM-625A Advanced Satellite Modem
MN-CDM625A
Appendix E
Revision 3
E–7
E.6 Frame Formats
Figure E-3 shows the supported E1 and T1 Frame Formats. Note that, for D&I++, the smaller
overhead frame structure does not support CAS signaling, although E1 timeslot 16 may still be
one of the channels transmitted.
Figure E-3. Supported T1 and E1 Framing Formats
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15
16 17 18 19 20 21 22 23 24 25 26 27 28 29 30
0
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
1
2
3
4
5
6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
1
2
3
4
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6
7
8
9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
1
2
3
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7
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9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24
E1-CCS (Common Channel Signalling)
2048 kbps E1 Frame Maximum channels to drop = 30 = 1920 kbps n x 64 kbps, n = 1,2,3,4,5,6,8,10,12,15,16,20,24,30
Time
Slot
No.
Time
Slot
No.
Reserved for
Framing
Reserved for
Framing
May be reserved for Signalling. All signalling
information is common to all 30 TS and no signalling is
transmitted.
Reserved for Signalling. All signalling is transmitted
for TS's dropped in IBS overhead (500Hz per TS)
Signalling information in TS 16 is associated to
specific TS's.
E1-CAS (Channel Associated Signalling)
2048 kbps E1 Frame Maximum channels to drop = 30 = 1920 kbps n x 64 kbps, n = 1,2,4,6,8,12,16,24,30
Time
Slot
No.
Time
Slot
No.
T1-D4 (D4 Framing)
1544 kbps T1 Frame 12-Frame multi-frame structure. No IBS multi-frame signalling will be transmitted.
Maximum channels to drop = 24 = 1536 kbps n x 64 kbps, n = 1,2,3,4,5,6,8,10,12,15,16,20,24
T1-ESF (Extended Super Frame)
1544 kbps T1 Frame 24-Frame multi-frame structure. No IBS multi-frame signalling will be transmitted.
Maximum channels to drop = 24 = 1536 kbps n x 64 kbps, n = 1,2,3,4,5,6,8,10,12,15,16,20,24