Dynamic Abis dimensionning [edge]

Hii PIX
thnks …..
plz explain me Tandem Free operation and it takes place at where BTS,BSC ,TRAU
regards

Hi Pix,

I have a few question regarding the activation of Edge in Alcatel B9 network.

1. what is the minimum required extra_ts on abis if I activate the Edge? At which MCS shall I start for this minimum extra_ts?

2. at the BSC what are the parameters that I need to enable to activate the Edge?

3. how do I define these extra_ts on the abis?

hi pix,

thanks for the reply it was enlightening but I have a few more questions:

1. where do I get to check that the trx are edge capable because we just migrated to B9 and we want to activate the edge for commercial use?

2. is it automatic that if we migrate to B9 all trx will be edge capable or these will only be on sites with twin trxs? what’s the difference between twin and regular trx?

3. like I said for commercial use what would be the safe number of extra_ts to be defined in order to ensure good throughput somebody told me to define at least 2 extra_ts? I know it depends on the traffic but initially I do have to define some extra_ts right? and these should be define on all the cells of edge capable trx?

4. these extra_ts, are they dependent on the abis capacity of the network? what if we dont have enough capacity on the abis?

5. lastly, what are the important KPIs that I need to check for EGPRS so I would know if the performance is good or not? what are the indicators that I must monitor to ensure that our Edge network is ok.

I am new to this Edge/GPRS technology so I have a lot of questions and believe me once it gets operational I will have a bundle. Thank you so much!

Paolo

hello paolo,

i’m gald i could help.
1- use the remote inventory (optionnal feature) to list all your hardwares in the network. The R.I. is accessible from the Icon Box, through a HTTP interface, as far as i remember.
if you don’t have the R.I., then you’re in trouble : you need to check each TRX one by one in the BSSUSM.

2- Twin TRX are EDGE capable, and so are the TRAG, TRAD, TRAGE and TRADE.
the Twin TRX contains actually two TRE’s into a “single TRE” sized module. That’s the main difference. In terms of “behaviour”, it is like any other TRX (I think they are based on TRAGE and TRADE)

3- obviously you need to perform a dimensioning for your network ! make assumptions on the expected packet traffic, the peak usages, the types of users, the GoS you want to provide, and so on. It is a very long and complex process, to be performed cell per cell on a radio planning tool.
If you want a simple answer, then yes, you can put 2 extra TS per BTS. You can also put 3, or 4, or 1. Or none. Or 15. It really depends on your traffic.

4- if you don’t have enough capacity on your abis, you add a secondary abis.

5- check the TBF establishment and drop rate (UL and DL). Check the Ater congestion (at GPU level). Check the average number of PDCH per cell. Check also the GPRS Distribution indicators (= GPRS RMS)

Paolo, you should contact Alc-Luc : they can put one expert on your network that can assist you on this project. If you don’t want that, then you could purchase a 3 or 4 weeks training course.. And the least you could do is to read the customer documentation : twin trx, secondary abis, extra timeslots : all this is described !
I’m afraid it’s a bit dangerous to improvise yourself as a EGPRS dimensioner and planner. You need some basic knowledge and documentations.

Do you have A9155 RNP tool ?

Regards,

hi pix,

thanks for the reply it helps a lot. No, we don’t have the A9155 Planning tool we only have the A9156 RNO tool. Anyway, I need to check on the documentations available so I could read more info on this. Again, thank you so much.

Paolo

trag and trad are EDGE capable.
the only drawback is the very low TX power they provide.
(column 1&2 : GMSK power, col.3&4 : 8PSK power)
TRAG 45W 46,5 15W 41,8
TRAGE 45W 46,5 30W 44,8
TAGH 60W 47,7 25W 44,0 (old high power trx)
TAGHE 60W 47,8 30W 44,8 (new high power trx)

Hi Pix,

So all these TRXs are edge capable but only with reduced TX power (less coverage area) – which means that the can use all the CS and MCS – right ?

Hi, Fahim.

“EDGE capable TRX” means that this TRX has a functional unit which is 8-PSK modulator/demodulator.

Because of the constant symbol rate in the radio path the difference between the MCSs is a different proportion between the useful data and the noise protection bits.
It’s more software than hardware.

In fact the high MCS depends on max MCS allowed ( parameter ), radio conditions ( C/I ) and Abis resources ( additional TSs )…
So it’s logical that the TRAGE could give you better C/I when transmitting DL TBF than the TRAG could.
But it’s wrong to say that this will give you a higher MCS automaticly.

In brief:
The abreviation means the max power of the hardware unit for the different modulations.
Yes, you can use all CS and MCS ( if it’s possible – permission, C/I, Abis ).

BR,

TNS