- This topic has 11 replies, 1 voice, and was last updated 13 years, 5 months ago by GM.
23rd June 2008 at 09:00 #52872ahmadGuest
can any body help about HO due to uplink signal strength and what is the solutions ( Dactive Uplink PC,????)23rd June 2008 at 19:09 #52873pixGuest
well, if PC thresholds and HO thresholds are set to default values, then a high amount of UL SS HO means that you probably have path unbalance.
Check your hardware at BTS side, it is probably a TRX problem.24th June 2008 at 07:23 #52874ahmadGuest
can you specify generally HO threshold parameters.24th June 2008 at 10:59 #52875pixGuest
can you list down your parameters, and i’ll whether they are good or not 🙂25th June 2008 at 05:25 #52876ahmadGuest
HO parameters are.
1- DL Quality threshold,UL Quality threshod.
2- DL Quality thrsh for interference HO the same as for UL.
3-DL RX level thrsh for Interfernce , the same as for UL
the values for first item is 6.5 for both DL and Ul, for second item is 6 and for third item is for UL is -95dBm and for DL -85dBm.25th June 2008 at 07:14 #52877pixGuest
the item 3 is the RXLEV below which there is a HO due to DL/UL signal strength ?
And above this value, it is considered as a interference HO if the RxQual is above 6, is it ?
The item 3 is set quite high, normally you should have -93dBm for DL and -103dBm in UL. So perhaps those thresholds overlap with your Power Control’s parameters ? What are the lower thresholds of UL and DL PC ?
Pix25th June 2008 at 11:00 #52878ahmadGuest
DL RX level lower thrsh is -80dBm and UL RX levl lower thrsh is -85dBm.25th June 2008 at 11:18 #52879pixGuest
ok.. well, it looks like the PC thresholds and HO tresholds are set correctly. I just think the HO signal strength are too high.
Anyway, can you check the TRX Path Balance for each TRX of this cell ?26th June 2008 at 08:10 #52880RamiGuest
When you mention HO due to uplink signal strength, it menas that the MS reaches its’ level on UL for HO. There is a window for which the MS will either power up or down to stay within this window. and I think the DL and UL (items # 1 & 2 are too high, try to reduce it) thresholds are high.
Are you facing this case insdie the city or in rural areas?
Regards,28th June 2008 at 06:17 #52881ahmadGuest
when item 1,2 is changed there was alot of improve both for RX quality and HO what to mean by reduce if I reduce it mean I loss my improvement in the network29th June 2008 at 10:24 #52882RamiGuest
I was just confused, it is on a scale of 1-100…you are right!
Please check SSDESUL, and if it is set to high values such as -75 dBm try to bring it to -85 or -90 dBm. Please try this in steps and not as one shot in order not to affect the network.
You should check as well QDESUL, it should have a value of 20-30 dtqu depending on you how much clean is your frequency plan.
Good Luck5th July 2008 at 19:11 #52883GMGuest
Given that no equipment is broken:
If you calculate the power budget (Linkbudget) for up- and downlink carefully you will find in many cases an imbalance. Either the uplink or the downlink is weaker. If the HO due to signal strength is enabled, you can easily see wheter the uplink- or downlink path is weaker – there will be more handover shown in the statistics. If necessary in coverage limited planning scenarios, a tower mounted pre-amplifier can be used to improve the uplink.