Changing PA in LTE

Hi Telecom family,
In which case we can change the PA (PA for even power distribution):question:
If we have one antenna we need to change PA to another value❓
What’s the consequences if done a wrong configuration❓
Vendor is Huawei

There is rule for it.
Combination of PA, PB and RS power depend on what purpose you want.
The concept is you can modify your RS power (-3 to 6) without changing RRU power by modifying PA & PB.
If done wrongly your script will be failed or sometimes cell down.

The rules said:
For PA
If we have a single antenna the PA is 0 dB;
If we have 2 or 4 antenna PA -3… And
PB range:
0 to 3
And if PA = 0 & PB =1 RS & PDSCH having same power
And RRU 20W.
If we change the RRU for 40Watt or 80Watt with a single antenna what we have to do use or configure❓

Yes all are true.
Antenna here means ports.
Single antenna = 1T1R; 2 or 4 means 2T2R or 4T4R.
Huawei by default using PA -3 and PB 1 not depend on RRU power.
Are you sure using only 1 antenna port without mimo?
For indoor maybe

MIMO 2 * 2 and 4 * 4…
One antenna

So consider as 2 and 4 antennas/ports at that description.
Fyi PA similar like dlrsboost in nok and crsgain in Ericsson.
For Huawei you can use the default value PA -3 and PB 1 which mean boosted by 3dB.

But for Huawei default PA= 0 & PB= 1 and Reference Signal 152 for RRU 20Watt
Band 20 MHz…

Its depend on your strategy, its ok if you want to have 0dB boost.
Will have better sinr, there is tradeoff.
Maybe other can give better understanding here.

Is there any PA PB parameter in Nokia?

Yes.
PA= dlrsboost
PB=hardcoded
But if your dlrsboost=0db you can set PB to 0 by set allowpbindexzero.

PB value is always zero irrespective of dlrsboost or will it change accordingly?

In Nokia it will change according to dlrsboost. 0-3 dB PB=1; 4.77db PB=2; 6db PB=3.
Can confirm from sib2 as well.

1 Like

hi,
let me correct here dlrstboost only for RS signal not for PA
allowpbindexzero for PB
no parameter for PA

show us your reference. We have many references and practical results.

allowPbIndexZero–>The cell specific PDSCH EPRE ratio to the cell RS EPRE (PB) can be set to zero.
If allowPbIndexZero is set to ‘false’ and dlRsBoost is equal to 0dB, then index 1 is chosen for pbIndexPdsch (instead of index 0)
dlRsBoost–>Transmission power of the downlink reference signals in a cell is boosted (positive value) respectively deboosted (negative value) compared to PDSCH

If dlrsboost modified will it affect to Pa ? The answer is yes. You can go deep detail in nokia reference for this.

Nothing need to be corrected in above explanation.