- This topic has 5 replies, 1 voice, and was last updated 12 years, 1 month ago by TNS.
5th April 2009 at 21:08 #56727RQGuest
What should be the value for the rx_lev threshold for intracell handover for uplink and downlink (u_rxlev_ul_ih / u_rxlev_dl_ih)?
In our network its value is 30 (-80 dbm).Is it not high enough? I mean when there will be poor quality(quality worse then the threshold) and the rx_level for the serving cell is greater then -80 dbm it will always try for intracell handover.So by giving this value (-80 dbm) we are reducing the chance for quality based inter cell ho.Should I reduce it (for example default value is 45.i.e. -65 dbm)?…what is the drawback and benefit of using -65 dbm or -80 dbm if that network has lots of interferences(both in hopping and BCCH)
Any body please suggest the value for this threshold….6th April 2009 at 13:00 #56728RQGuest
Any 1 can help me please about that issue?
thanks6th April 2009 at 14:06 #56729TNSGuest
-65 dBm is oK.
It’s useless in case of hopping.
BR,6th April 2009 at 20:08 #56730RQGuest
Can u please describe why does it useless in case of hopping as u mentioned.
thanks7th April 2009 at 20:52 #56731RQGuest
by giving the threshold to -80 dbm I think we are giving more priority to the intracell ho.
So I think I should increase it like (-65 dbm)7th April 2009 at 21:20 #56732TNSGuest
So, this is the idea…
Let’s say you have two TRXs with BCCH freq 20 and TCH freq 35.
Without BBH you get a TCH on freq 35. Very good level -60 dBm but low quality => interference.
Then the BSC assign you a TCH on the BCCH TRX ( freq 20 ). There you have the same level but better quality due to clear BCCH freq.
With BBH you get a TCH on the TCH TRX. Very good level but bad average quality due to very bad freq ( BCCH 20 or TCH 35) or both.
You perform a intracell HO and you get a TCH on the BCCH TRX. The same level again, but the same quality because of the average value on the hopping sequence ( freq 20 and freq 35 ).
Then you perform a new intracell HO and again… and again…
A loop with unknown end :- )
Of course performing this HO we keep the freq band ( it’s not inner zone to outer zone HO and vs… ).