1 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

Company Confidential

208 Report Analysis

2 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

Company Confidential

Case1: Jumper from TRX 4 to combiner loose (check connectors at both ends)

Case2: Jumper from Duplexer to TRX 4 (check connectors at both ends)

Case3: Check common feederline from Top of cabinet to Antenna port ( loose connector’s at either end or High VSWR problem, TRX 2&4 in this case use the same feeder)

In this case, the Path imbalance (DL-UL) varies between +1.6 to -4dB which doesn’t tell much

BUT DL pathloss variations between TRX’s is from 112.8 to 136dB

& UL pathloss variations between TRX’s is from 111.2 to 140dB

DEFINITELY A PROBLEM!

3 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

Company Confidential

Use OSS Data to identify & pinpoint HW faults faster

Sector A

0.00

10.00

20.00

30.00

40.00

50.00

60.00

70.00

80.00

>70dBm 70-80dBm 80-90 90-100dBm <100dBm

Downlink Signal Strength

TRX3

TRX4

TRX5

TRX6

Sector B

0.00

20.00

40.00

60.00

80.00

100.00

120.00

>70dBm 70-80dBm 80-90 90-100dBm <100dBm

Uplink Signal Strength

TRX3

TRX4

TRX5

Path Balance Reports help understand any imbalance between UL and DL

Whereas

Eg.Pathloss comparisons between TRX’s of same sector can help identify loose cables or hardware faults, taking other TRX’s as reference case

Eg. In Sector A:TRX 3 &4 have only 20% of DL SS samples <-100dBm whereas TRX 5 & 6 have 70% of their DL SS samples <-100dBm.

Prob:1 Combiner Faulty

In Sector B TRX 5 clearly had a difference in signal strength only in Uplink.

Prob: Rx cable found to be loose

The same faults can also be seen using Rxlevel statistics from OSS shown in this slide, but 208 is faster for analysis!

4 © 2005 Nokia V1-Filename.ppt / yyyy-mm-dd / Initials

Company Confidential

How to identify the worst cells in your network?• Import DL & UL pathlosses for all

TRX’s of all cells into separate columns

• Use a pivot table to get Min and Max values of dL and Ul pathlosses in a cell

• Identify all cells with DL TRX pathloss variatons >10dB(for a NW with huge TI quality issues , sstart with 15dB)

• The same can be done for UL also

• A combined analyses for DL& UL with >10dB diff gave a list of 58 cells for UP(West) attached below.

• Go back to 208 report for detailed analysis

208_HW issues