Patton electronics G.SHDSL NTU, User Manual

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G.SHDSL NTU User Manual V0.03 80
PCM30 and PCM30C / FAS+CAS and FAS+CAS+CRC4
FAS
0 1 2 3 4 16
31
Time Slot
64k 64k 64k 64k 64k 64k 64k 896k
17 ~ 30
CAS
5 ~ 15
704k
Data Rate (x) 960kbps Data Rate (y) 960kbps
Maximun Data Rate = x + y = 1920kbps
CRC4
The CRC-4 checksum bits are transmitted in the outgoing E1 data stream.
Also the received signal is checked for errors.
CRC-4 checksum cannot be sent in unframed mode.
Unframed
In this mode, user data is inserted into all 32 channels (64k x 32 = 2048k) of
the E1 stream. The object of running without framing is to utilize the full
bandwidth of the E1 line.
UNFRAMED
0 1 2 3 4 5 6 7
8 31
Time Slot
64k 64k 64k 64k 64k 64k 64k 64k 64k 64k 1408k
9 ~ 30
Maximun Data Rate 2048kbps
G.703 (E1) can supports data rate of 2048kbps, so the maximum data rate of SHDSL line, connected with E1 DCEs,
depends on data rate of E1, 2048kbps.
STU-C (E1)
STU-R (E1) DTE DTE
E1
E1 SHDSL
Frame E1
Data rate 2048
If the connection is E1 vs V.35 or V.35 vs E1, the frame has to be used N x 64k. In this case, the data rate depends on
value of N. Same as above case, SHDSL and V35 can support 2304kbps data rate (36 x 64k) but E1 supports
maximum data rate of 2048kbps (32 x 64k).