# Maximum Transmit Power with mMIMO

Hi Experts,
Using AAU5711a (32R32R160W) in LTE1800 with mMIMO - 4 cells per sector. Can I I use 5 W (37dBm) as “Maximum Transmit Power”?

Is there interference problem?
Why would you not use 40 W per cell?

Today I have 35.2dBm (3.31W) per cell (1 sector).
Why can´t configure 37dBm (5W)?

I’ve 4 cells per sector using 32T32R (AAU).

From specs, Maximum OutputPower por PA (32T) for this AAU is 5W.

Is this total cell transmit power?
Or total RS Power?
Maybe a question to some Huawei mMIMO expert.

This is Maximum Transmit Power (0.1dBm) = 35.2 dBm.

5W is per antenna element, so you have 160 W for 32 antenna elements.

The max you will be able to configure is 1.25 W per PA per Cell.
Because 1.25 x 4 = 5 W.
5 W x 32 = 160 W.

1 Like

The Reference Signal Power (0.1 dBm) por cell is 9.7 dBm, Pb = 1dB and Pa = -4.77 dB.

OK.
How Huawei configured 3.31 W without alarm?

Very good question, we don’t create energy from nowhere…

Sure, this is the question.

I know you can configure less power per cell, and the remaining power can still be allocated to different layers to increase MCS distribution when you have high distribution of higher order layers utilization.
But it’s a very good question how the total power configured is higher than the RRU capacity.
Unless the allocation is dynamic among the 4 cells according to utilization (I don’t believe so).

Here you have an online calculator for rs power in LTE:

And bandwidth as well; just need to input 160 Watts and 4 TX for 4 x 4 mimo.and RS Power result is 18.2288.

Thanks @RFSpecialist, but AAU5711a has 32T32R.

32T32R are not refering to MIMO modes.
But to number of radiating antenna elements that generate the beamforming.

I know I cant use 18.22 dBm as RS.

What’s your Bandwidth? 20 Mhz or less?

15 MHz. And remember I have 4 cells per sector.

Ok, so it goes like this:
With 15 M hz and only 2 x 2 MIMO: 27.2494 dBm

I can’t set 27.24dBm per cell: 4 cells per sector.