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kkagimu
2011-07-27, 04:18 PM
hello everyone
What is solution to high rtwp valves. there is a certain sector in the network experiencing a high rtwp valve. site has been on AIR for more than a year but the problem started recently

twenty8
2011-07-27, 04:27 PM
Hi,
Propose to check PrxNoise values in the cell. also check if there is high number of HSUPA usage in the cell as this can cause high noise rise especially > 1.4mbps on UL.

kkagimu
2011-07-27, 04:32 PM
wat counter can i use to find the prxnoise valve? thanks for your help?

balachandrun
2011-07-27, 06:20 PM
please check the cell load, monitor the cell TCP....hardware faults can cuase high RTWP.... like faults in feeder,connectors may cause IInter product modulation...

boring
2011-07-27, 06:28 PM
it is critical to see how ul interference behaves during a 24-hour period

is it during BH? then it could be because of HSUPA users (admission control must be configured properly)

HW issues could always be the problem. this will show high interference during night time in most cases

also don't forget external interference (but here you need to do a site visit and to use a spectrum analyser)

mulham_kh
2011-07-27, 08:42 PM
I think you have to check if there is a swap Feeders between two sectors or if there is any external interference , and the easiest way is to see if the high RSSI occurs in all Hours or in the peak hour only.

adewijaya
2011-07-27, 10:23 PM
which one alarm happend ?

1. ALM-26522 RF Unit RX Channel RTWP/RSSI Unbalanced
Possible Causes
a.The main RX channel or diversity RX channel of the RF unit is faulty.
b.The setting of attenuation on the RX channel of the RF unit is incorrect.
c.External interferences exist on the main or diversity antenna of the RF unit.
d.The feeder connected to the RF unit is faulty, which results in a high passive intermodulation power of the main antenna.

2. ALM-26521 RF Unit RX Channel RTWP/RSSI Too Low
Possible Causes
a.The setting of attenuation of the RF unit is incorrect.
b.The TMA is faulty.
c.The feeder installation is improper. For example, the feeder connector is loose, soaked or damaged, or the feeder is deformed.
d.The RF unit is faulty.

3. ALM-26239 RX Channel RTWP/RSSI Unbalanced Between RF Units
Possible Causes
a.The main RX channel or diversity RX channel of the RF unit is faulty.
b.The attenuation setting of the RX channel of the RF unit is incorrect.
c.External interferences exist on the antenna connected to the RF unit.
d.The feeder connected to the RF unit is faulty, which results in a high passive intermodulation power of the main antenna.
e.The RF unit malfunctions.

redtomato168
2011-07-29, 01:16 PM
it is critical to see how ul interference behaves during a 24-hour period

is it during BH? then it could be because of HSUPA users (admission control must be configured properly)

HW issues could always be the problem. this will show high interference during night time in most cases

also don't forget external interference (but here you need to do a site visit and to use a spectrum analyser)

our network also have high UL interference, high RTWP in BH, cause HSUPA users. How to correct configured?

jan74
2011-07-29, 04:29 PM
our network also have high UL interference, high RTWP in BH, cause HSUPA users. How to correct configured?

If you have high RTWP and your PrxNoise is still at normal values like -104dBm to -106dBm, the likelihood is that its caused by HSUPA users and its down to traffic. Check all your neighbours are in place to be sure.

boring
2011-07-30, 06:08 PM
our network also have high UL interference, high RTWP in BH, cause HSUPA users. How to correct configured?

which vendor are you using?
have you activated admission control in the uplink?

twenty8
2011-08-01, 10:26 PM
Hi PrxNoise will not take into account the traffic power,hence this is the first things to check. If abnormal readings (stronger then -100 dbm) , then you should check alarms , possible hardware or ext interference.

If PrxNoise is normal , the high RTWP could be due to HSUPA traffic. Can you check which feature of HSUPA is enabled ? ie. is it 1.4Mbps , 2.8Mbps, 4.2Mbps or 5.6Mbps. The higher the tp for HSUPA is enabled the higher is the noise rise , hence this needs to be inline with the planning strategy. You can use the UL interference margin parameter to control this noise rise which will in turn limit the throughput.

/28

adewijaya
2011-08-01, 10:43 PM
better you prove it with data or statistic ;)

zeezzoo
2011-08-01, 11:30 PM
does huawei have something called Prxnoise measurements ??

adewijaya
2011-08-01, 11:40 PM
no, its called RTWP on Huawei System

Philippe
2011-08-02, 01:08 AM
Prxnoise is the indicator name in NSN equipment for the total Noise level without load:

"PrxNoise defines the noise level in the BTS digital receiver when there is no load (thermal noise + noise figure)."

RTWP= PrxNoise + Interference Margin

twenty8
2011-08-02, 04:28 PM
Actually in NSN there is both PrxNoise and RTWP , as both counters serve a different purpose.

In Huawei case, without prxNoise measurements how would you identify cells which are experiencing high noise floor ?

Philippe
2011-08-02, 08:03 PM
You can also refer to the follwowing post http://www.finetopix.com/live-optimization/19641-what-prx-noise-prx-total.html

For a 2dB Noise Figure NodeB, the PRxNoise or RTWP without load should be around -106dBm (=-174+10*log10(3840000)+2).

kkagimu
2011-08-02, 08:26 PM
we are using alcatel_lucent.a

qt_raip
2011-08-08, 05:45 PM
Hi!

I'm a new member here and I would like to ask your help because we're having the same problem with our site.

We're experiencing high RTWP with 3 operators(shared in the same DAS system), also experiencing high number of sdrop? what would be tha cause of these problem "

twenty8
2011-08-09, 12:15 AM
High PrxNoise also occurs when you configure your PA or TMA incorrectly. In the case of inbuilding, I guess there must be some incorrect setting in the link budget ? What type of system are you using ? Active or Passive ?

qt_raip
2011-08-11, 04:55 PM
We are using passive design; is there any method that we can follow on isolating the problem if it’s coming from external or internal interference?