During Swap WiMAX Project in Country I, Operator S declared already shutdown all the BTS WiMAX under their network via NMS. Their LTE network will used the same allocation of frequency 2360~2390 MHz. During shutdown BTS WiMAX, some site have to be disconnected to ASN GW due to no power supply available. Cause Analysis: LTE and WiMAX that operator S implement using TDD Ratio 32:15 for and 3:1 for LTE. Without modified the timing shiting, it will be interferer WiMAX to LTE. Than by using the Huawei Spectrum Analyzer, we can find the signal form from interference source. Handling Process: We have to mapping the all site included WiMAX site that not yet shutdown before. After the the power available again the WiMAX BTS will transmit the signal even the core is not connected (in LTE technology, if eNB have problem in S1 interface will be not transmit the signal)

1. TD-LTE Project
www.huawei.com
www.huawei.com
Interference Investigation
TD-LTE Radio Network Optimization
Author/ Email: Ray Khastur
Version: V1.0(20130727)

2. Author / ID
Ray Khastur
Co-author / ID
Approver / ID
Description
VVIP Area Interference Analysis
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3. Interference Investigation
Using TD-LTE Spectrum Analyzer and eRAN
TDD FMA

4. M2000-Interference Monitoring
On the M2000 for site Imperial Arya Duta we can see there is high UL interference detected.
* UL Subframe 0 and 6 used for TDD Long Distance Interference Analysis
** UL Subframe 0 and 11 used for GPS Interference Analysis
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5. Call History Log Analysis
Based on CHR Data,
Service Drop occur
when UL Radio
Condition detected
UL Interference
5

6. MatLAB Analysis

7. PCI Conflict Check
There is no PCI
conflict detected
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8. Frame Structure
D
U
S
D
D
D
U
D
D
S
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9. Animation of Interference on Special Subframe
Dw Dw Dw Dw Dw Dw Dw Dw Dw Dw GP GP Up
Up
0
13
1
2
3
4
5
6
7
8
9
10
11
In Guard Period
should be there is
no activity detected
during this silent
period.
We can conclude
the Interference
occur in every time.
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12

10. Animation of Interference on UL Subframe
F1
F4
F2
F3
Subframe 2 used
for UL Data, there
are 4 in band
external source with
different signal
strength of
Interference
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