[somnath dutta]

With some IMSI value,CCCH_CONFIG=0,BS_AG_BLK_RES=1,BS_PA_MFRMS=4,how to calculate the actual paging group?I want the actual value of the paging group.Plz help.

[Garry]

32 paging groups with non combined and 8 with combined.

[somnath dutta]

No I want the actual paging group which is assigned for me.That means how to calculate the actual paging group based on my IMSI/TMSI which is assigned to me.

[pix]

there’s a formula, that you can find in a 3GPP document.
http://www.3gpp.org

[somnath]

Actually I have tried to calculate the same using that formula…but there Im facing some prob where mod value is returning a ‘0’…which is meaningless…so I feel Im doing some mistake somewhere.So can you help?

[pix]

yes, but you’ll have to give me the formula, so i can give it a try. No time to look for the formula by myself, sorry…

[somnath]

pagging_group(0….N-1)= (IMSI mod 1000)mod N

N=(no of CCCH group in a multiframe-no of blk for AGCH)*no of multiframe between pagging
for instance no of CCCH blk available=9,AGCH blobked=1,
no of pagging between multiframe=4

plz help

[pix]

IMSI mod 1000 –> gives you the 3 last digits of the IMSI

3 last digits mod 48 –> in excel, type the formula
“=MOD(3digits;48)”

why 48 : because (9-1)x4 = 48

the result is the value of the paging group…

regards,
pix

[somnath]

It will be 32 instead of 48 because
(9-1)*4=32

[pix]

what a shame… thx somnath, i’m doing really stupid mistakes sometimes ! :))

i was even wondering how come a “modulo 48” was used, while there is about 20 to 30 paging groups normally… never crossed my mind that 8×4 = 32.

[anh]

Let say, we have 100 IMSIs belonging to paging group No.2
With paging request type 3 (4 MS per paging msg), how will these 100 IMSIs be paged?

Thanks,

[pix]

hi,
these Ms will be paged by their TMSI, if the MSC has allocated a TMSI to these MS, and if the “TMSI paging” method is defined in the MSC.

If anyone has more info, welcome to share…

regards
pix

[Mick]

In case of Paging Request Type the mobile stations are identified by their TMSIs (TS 04.08)

[Deepak]

CCCH-CONF Value tells,Whether you are using COMBINED or NON-COMBINED Configuration.
I dont remember exactly, What exactly CCCH_CONFIG=0 stands for.

First lets Consider COMBINED config

COMBINED : Total CCCH = 9
BS_AG_BLK_RES=1
So Channels reserved for Pagig = 9-1 = 8

BS_PA_MFRMS=4 : This tells After how many multiframes paging group repeats.

So total Paging groups = 8*4 = 32

Lets IMSI Value = x

Paging Group for a particular Mobile =

(x MOD 1000) MOD 32 where 32 is total Paging Groups.

e.g. if IMSI = 404685505601234
Paging Group = (404685505601234 MOD 1000)MOD32
i.e. => 234 MOD 32 => 10

Paging Group = 10.

NON-COMBINED:

Total CCCH = 3
BS_AG_BLK_RES=1
So Channels reserved for Pagig = 3-1 = 2

BS_PA_MFRMS=4
So total Paging groups = 2*4 = 8

Paging Group = (IMSI MOD 1000)MOD 8

e.g
404685505601234 MOD 1000 MOD 8
=> 234 MOD 8 = 2
Paging Group = 2

I hope this answers your query

[Author]

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