- This topic has 16 replies, 1 voice, and was last updated 11 years, 3 months ago by Johny.
16th March 2011 at 16:46 #65980MuradGuest
Our Half rate usage very high in our BSC i want to remove HR on some rural sites but before i need to change threshold for TCH assignment for HR and FR. Can anybody tell me what is this threshold for & what can be the benefit if i change this threshold16th March 2011 at 20:01 #65981pixGuest
which equipment are you using ? alcatel ?17th March 2011 at 07:19 #65982fdrGuest
you can change this value. for example %30 half %70 full or %40 %60 ….
its mean that your cells FR usage for all timeslot 70 or big value that you must usage for other call just on the HR timesolt17th March 2011 at 16:36 #65983muradGuest
We are using NSN.ALU and huawei17th March 2011 at 19:26 #65984pixGuest
the thresholds might have different effects in different vendors, so be careful. I’m going to talk about alu only.
you say that there is too much HR usage in rural sites.
1/ could you give me the rtch_traffic_erlang_hr_bh and rtch_traffic_erlang_fr_bh in a typical rural area (the total value in a whole “rural” bsc)
2/ what is the rtch_na_congestion_rate_bh (RTCNACGR) in this bsc ?
pix18th March 2011 at 15:16 #65985MuradGuest
Thanks a lot for you reply. I checked and found out it is ok for ALU and worrying just for NSN
I found out below parametrs which needs to be change for reduce HR usage for AMR calls
BtsSpLoadDepTCHrate Upper –> Upper limit for FR TCH Resources (90%)
BtsSpLoadDepTCHrate Lower –> Lower Limit for FR TCH Resources (60%)18th March 2011 at 16:46 #65986bjushkaGuest
If you are going to deactivated HR for these cells, why dont you use default value of these two parameters: FRL = 100% and FRU = 0%.
bjushka19th March 2011 at 07:31 #65987pixGuest
i worry that by reducing the HR usage, you will increase congestion.
the upper limit = 90% –> increase it to decrease HR usage (100% means that HR can’t be used)
the lower limit = 60% –> when load goes below 60%, calls are setup in FR. –> increase it to decrease HR usage
upper limit = 95%
lower limit = 80%
what’s for sure is that if the load of the cell goes above 95%, HR will be used.
But if that’s the case, that’s very good… because if hr was not used, then the cell would be congested.
With your current setting (90%), i think your HR is already doing a very necessary job ! Don’t try to reduce HR usage… without it, congestion would jump !21st March 2011 at 08:28 #65988bjushkaGuest
I recommended these thresholds only in case HR is not needed for respective cells, and HR license would be removed. Murad are you going to remove HR license of you want only to reduce HR usage in the network without deactivating HR license? (this is traffic based)
bjushka23rd March 2011 at 07:16 #65989MuradGuest
Sorry for late reply
the upper limit = 90% –> increase it to decrease HR usage (100% means that HR can’t be used)–> i used this for non AMR calls
i am thinking to change this threshold for remote areas sites.
All these threshold are beased on free TS. ALU and NSN have different strategy for this threshold i mean in NSN THRESHOLD will start from 100% but ALU starts from 0%
Upper limit for FR TCH Resources (90%)–> Starts to calcualted from 100% to 0 % which means cell load from 90% to 60 % cells starts to Pack the TS to HL below 60 % all calls will be in FR
i dont know is it clear or not 🙂23rd March 2011 at 07:19 #65990MRDGuest
I will try to use on one cell let me see the result and will infrom you23rd March 2011 at 07:20 #65991MRDGuest
I want without deactivating the HR license to reduce HR usage28th March 2011 at 06:55 #65992bjushkaGuest
hi MRD (is the same name with MURAD?),
ok then, here is my opinion about these two thresholds:
(I will take an example with HR used for 8 TS)
– FRU(90%)means that FR TCHs are again allocated when the number of the free FR resources INCREASES above 90%.
example: 90% of 8TS = 7.2TS. In this case, FR TCHs will be allocated if 7 or more FR TCHs are
available, if FR TCHs are lower than 7TS, than HR TCHs will be allocated.
– FRL(60%)means that HR TCHs are allocated when the number of the free FR resources DECREASES above 60%
example: 60% of 8TS = 4.8TS. In this case, HR TCHs will be allocated if 4 or fewer FR TCHs are available.
So I think that HR usage is to high with these thresholds and I would recommend to use the above thresholds, in order to avoid even possible congestion:
FRU = 15% (15% of 8TS = 1.2TS)
FRL = 7% (7% of 8TS = 0.56TS)
I hope I could help
Any suggestion or correction is welcomed 🙂
bjushka28th March 2011 at 19:44 #65993pixGuest
yeah, totally different mechanisms between alu and nsn, i should have shut up 🙂 sorry if my explanations disturbed other helpers.
thanks for enlightning me 🙂29th March 2011 at 09:33 #65994bjushkaGuest
Yes these are the thresholds used with NSN features.
I am happy to help 😉