Figure 7-3 E1 Link Between The Bts And The Bsc (2) - Huawei BTS3900 GSM Commissioning Manual

7 FAQs for BTS Commissioning
l
Example Two: Check for UELP Faults Through Physical Loopback Test
7-4
1. Check for the crossed pair connection on the E1 cable between the DDF on the BSC
side and the BSC.
(1) Perform a physical loopback on each E1 cable at the DDF subrack of the BSC,
as shown in
(2) Run CHK E1T1CRS to query the results. If the results of all the ports are NOT
CROSS, you can infer that the E1 cable is correctly connected on the BSC side.
If the results are CROSS EXIST, correctly connect the E1 cable to this port.
(3) Restore the E1 connections between the BSC and the DDR. That is, connect port
C1 to port A1 and connect port D1 to port B1.
2. Check for the crossed pair connection on the E1 cable at the DDF subrack of the BSC.
That is, connect port A1 and port B1. The detection method is similar to that in 1.
3. Check for the crossed pair connection on the E1 cable between the DDF subrack of
the BTS and the DDF subrack of the BSC. That is, connect port C0 and port D0. The
detection method is similar to that in 1.
4. Check for the crossed pair connection on the E1 cable at the DDF subrack of the BTS.
That is, connect port A0 and port B0. The detection method is similar to that in 1.
E1 link between the BTS and the BSC (2): BTS→DDF on the BSC side→BSC, as shown
in Figure 7-3.

Figure 7-3 E1 link between the BTS and the BSC (2)

E1/T1
E1/T1
BTS
1. Check for the crossed pair connection on the E1 cable between the DDF subrack of
the BSC and the BSC.
(1) Perform a physical loopback on each E1 cable at the DDF subrack of the BSC,
as shown in
(2) Run CHK E1T1CRS to query the results. If the results of all the ports are NOT
CROSS, you can infer that the E1 cable is correctly connected on the BSC side.
If the results are CROSS EXIST, correctly connect the E1 cable to this port.
(3) Restore the E1 connections between the BSC and the DDR subrack. That is,
connect port C to port A and connect port D to port B.
2. Check for the crossed pair connection on the E1 cable at the DDF subrack of the BSC.
That is, connect port A and port B. For details, see 1.
NOTE
The physcial loopback test in this example is applicable to check for the improper E1 connection on the
BTS side.
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Figure 7-2. Connect port C1 and port D1
A
B
Figure 7-2. Connect port C and port D.
Commissioning Guide
C
E1/T1
E1/T1
D
DDF
Issue 02 (2009-04-20)
BTS3900(A) GSM
BSC