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Muhammad Imran Rafique
2012-06-10, 04:44 AM
Dear All,

In E******* WRAN, these two parameters by default are set to 621 & 6000(49.9dBm & 600 secs). It means not activated at all, what can be optimal settings for externally interferred areas?

Has anybody tried it, kindly share any impact report.

BR//
Imran

ninjafine
2012-06-11, 01:59 AM
Dear All,

In E******* WRAN, these two parameters by default are set to 621 & 6000(49.9dBm & 600 secs). It means not activated at all, what can be optimal settings for externally interferred areas?

Has anybody tried it, kindly share any impact report.

BR//
Imran

Hi! In case of UL RSSI > iFcong then UL RTWP Congestion Triggered.
Depending on Interference level and iFcong you will get Drop RAB or RRC % increased and deceased CSSR RAB or RRC %.

Thanks and reps are appreciated.

Muhammad Imran Rafique
2012-06-11, 04:47 AM
Have anybody tried these two parameters, i am looking for an impact report.

BR//Imran

ritgail
2012-07-08, 02:20 PM
hi,

If you want to control UL RSSI, then this parameter needs tuning. Generally, you can tune it with

ifcong = thermal noise+noise figure+ul inconsistency+headroom for services
=-107 dBm+ 2+ 2+ c
= approx -98dBm

There is a parameter separately for EUL congestion.

the threshold (iFCong) & hysteresis (iFHyst) used for detecting &
resolving UL Cell Congestion. By default, this policy is disabled. Usually, UL
interference is not the main limitation and this setting is acceptable in most cases. If
there is a high degree of uplink interference in a cell, it can be relevant to tune these
parameters to resolve excessive cell breathing.

RBS counter pmAverageRssi can be used to measure RSSI distribution as an input to
set iFCong. Detection of UL Cell Congestion could be on a level which is around 2
dB extra noise rise (parameter iFCong). In general, the expected level of UL RTWP
is formed by the sum of the following components:
• Thermal noise floor (for example, -107.5 dBm)
• RBS noise figure (typically 2 dB with E******* ASC/TMA or 3 dB without)
• Noise rise due to load (60% loading in uplink corresponds to 4 dB)
• Compensation for inaccuracies in Radio Network algorithms (around 2 dB)
When setting parameter iFHyst, short duration of UL interference peaks should be
disregarded as, in general, they do not lead to uplink cell congestion.
The RTWP figures are likely to be affected by EUL introduction. Therefore, the
impact of EUL users and scheduler related parameters such as
eulMaxRotCoverage, eulMaxOwnUuLoad and eulMaxShoRate should be
considered in case the congestion control policy is activated.

JCarlos21
2012-07-12, 03:14 AM
Hi Rafique,

This feature is not likely used in case of external interference (high RSSI no caused by high traffic) because gives wrong idea to the RBS of UL Congestion.

When dealing with high RSSI you should do a few steps before applying UL Congestion Dectection (enabling iFCong/iFHyst):

1. See jumpers and connectors of RBS installation.
2. See attenuation for RSSI calculation.
3. Are there any repeater nearby the Node B.
4. High traffic should be optimized among neighbor cells or maybe another carrier.

Regards,



Dear All,

In E******* WRAN, these two parameters by default are set to 621 & 6000(49.9dBm & 600 secs). It means not activated at all, what can be optimal settings for externally interferred areas?

Has anybody tried it, kindly share any impact report.

BR//
Imran