Path Balance

Path Balance (Huawei) Path balance stats are used to identify hardware issues in the base station. Therefore it is important to check path balance stats when you suspect hardware issues with degradation of KPIs. Following equation should be satisfied if up link and down link is balanced (Huawei). Downlink receiving level - Uplink receiving level – (MS sensitivity - BTS sensitivity) = 0 dB

The equation will be changed as per Huawei BTS sensitivity and MS sensitivity, Downlink receiving level - uplink receiving level - 6 = 0 (Rank6) Following table is used to matching path balance difference and Ranking. Uplink and downlink balance level

Downlink receiving level - uplink receiving level - 6 (dB)

Rank 1

≤-14

Rank 2

-13 ~ -11

Rank 3

-10 ~ -8

Rank 4

-7 ~ -5

Rank 5

-4 ~ -2

Rank 6

-1 ~ 1

Rank 7

2 ~4

Rank 8

5~7

Rank 9

8 ~ 10

Rank 10

11 ~ 13

Rank 11

≥14

In ideal case when all the samples should be Rank 6 if path is balance. But in actual case sample distribution will be as follows.

Sample distribution (TRX with balanced uplink & downlink) 18000 16000

Samples

14000 12000 10000 8000 6000 4000 2000 0

Rank 1

Rank 2

Rank 3

Rank 4

Rank 5

Rank 6

Rank 7

Rank 8

Rank 9

Rank 10 Rank 11

Rank

High path loss in down link If there is high path loss in down link, then downlink receiver level (MS receiver signal strength) will be low. Then path balance formula will result negative values. Downlink receiving level - uplink receiving level - 6 < 0 Then high portions of samples will have rank 1 to rank 5. Sample distribution (TRX with high downlink loss) 14000 12000

Samples

10000 8000 6000 4000 2000 0

Rank 1

Rank 2

Rank 3

Rank 4

Rank 5

Rank 6

Rank

Rank 7

Rank 8

Rank 9

Rank 10 Rank 11

Sample distribution (TRX with high downlink loss) 16000 14000

Samples

12000 10000 8000 6000 4000 2000 0

Rank 1

Rank 2

Rank 3

Rank 4

Rank 5

Rank 6

Rank 7

Rank 8

Rank 9

Rank 10 Rank 11

Rank

High path loss in up link If there is high path loss in up link, then uplink receiver level (BTS receiver signal strength) will be low. Then path balance formula will result positive values. Downlink receiving level - uplink receiving level - 6 > 0 Then high portions of samples will have rank 7 to rank 11. Sample distribution (TRX with high uplink loss) 14000 12000

Samples

10000 8000 6000 4000 2000 0

Rank 1

Rank 2

Rank 3

Rank 4

Rank 5

Rank 6

Rank

Rank 7

Rank 8

Rank 9

Rank 10 Rank 11

Sample distribution (TRX with high uplink loss) 14000 12000

Samples

10000 8000 6000 4000 2000 0

Rank 1

Rank 2

Rank 3

Rank 4

Rank 5

Rank 6

Rank

Rank 7

Rank 8

Rank 9

Rank 10 Rank 11