How to calculate RS power?

How to calculate RS power in LTE?

If i have 20 MHz bw, by 80 W power, what will be the exact RS on the field?
Vendor is Ericsson.

Generally rs power = pmax - 10 log 10 (number of rb * 12 ) + any mimo gain.

Please use above formula and check in sib2 if value matches or not for rs power you calculated.
Pmax in dBm in above formula.

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Find EPRE in type-A symbol and then use Pa, Pb values to find RS Power.

20 MHz BW, this implies 100 RB X 12 RE -> 1,200 RE

Total power = 8 W = 80,000 mWatt
Power per RE = 80,000 /1,200 = 66.66 mWatt

Let’s say Pa = -3, this implies Reference Signal is 3 dB stronger
(In Ericsson it’s equivalent to CRsgain = 300)
3 dB means double
So RS power will be 66.66 x 2 = 133.32 mili Watt

Convert it into dbm
10 log (133.32 mW / 1 mW) = 21.24 dBm

Assuming Pb = 1
Otherwise there will be power imbalance [either over or under Utilization]

Another assumption is 2x2 MIMO enabled.

Hope you got it :)… Cheers :blush:

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Appreciated. :slight_smile:

And how about if it have crsgain = 0?

It means RS power will be same as of EPRE.

So we calculated EPRE = 66.66 mWatt

In this case RS Power will be same i.e. 66.66 mWatt

Convert it into dBm.
10 log (66.66 mW / 1mW)
RS Pwr = 18.2386 dBm

:slightly_smiling_face:

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Nice explanation @AbdurRehman87, thanks! :wink:

How to calculate the RS Power in 5G

Is RS Power/PDSCH Power ‘configurable parameter’ or does system calculates it (RS Power/PDSCH Power) based on RU Power / CRS Port / Bandwidth used?

It is Vendor specific.

For ex: In Huawei it is ‘configurable’ while in Nokia is ‘system caculated’.

Hello Experts!

Could someone explain to me, or share some technical article about this calculation of RS ?
I would like to understand this equation (RSRP=RSSI-10log(12N)). Does this relationship between channel power (RSSI) and RSRP power come from where?
How to apply it in the calculation of the 5G RSRP, whereas the SSB occupies only 20RB’s within the entire band ? These topics I’d like to understand better.