Atoll Atoll.Std.x64.3.3.2.11009_RS EPRE per antenna port_Feature

[slava121]

Good day to all!
In Atool found a very unusual feature of calculating RS EPRE per antenna port.
The value of RS EPRE per antenna port depends on the Max Power (dBm) and PDSCH EPRE Offset / RS, PDCCH EPRE Offset / RS. The calculation was performed for the Calculated (with boost) mode.
In the LTE Cells table, Max Power (dBm) = 46dBm was set. The power of the reference signal PS Power = 18.23 dBm, with the PDSCH offset values ​​EPRE Offset / RS = 0 dB, PDCCH EPRE Offset / RS = 0 dB, for configuration: two antenna ports for transmission, two antenna ports for reception. BW = 20 mHz; RB = 100.
In the table Cells Details received the data: RS EPRE (CE) = 15.2 (dBm); PDCCH EPRE (CE) = 15.2 (dBm); PDSCH EPRE (CE) 15.2 (dBm), etc.

1. By what formula does the calculation of RS EPRE in Atoll?
2. What is the dependence of RS EPRE on PDSCH EPRE Offset / RS, PDCCH EPRE Offset / RS?

Regards, Slava

[slava121]

Good day!
Good afternoon!
Here are the values ​​of RS EPRE per antenna port (dBm) for various Max Power (dBm).
What is the formula for calculating RS EPRE per antenna port?
Regards, Slava.



Transmitter
Frequency Band
Max Power (dBm)
RS EPRE per antenna port (dBm)
SS EPRE Offset / RS (dB)
PBCH EPRE Offset / RS (dB)
PDCCH EPRE Offset / RS (dB)
PDSCH EPRE Offset / RS (dB)


156_LTE_2
E-UTRA Band 3 - 20MHz
46
15,4
0
0
0
0


156_LTE_3
E-UTRA Band 3 - 20MHz
46
15,4
0
0
0
0












156_LTE_2
E-UTRA Band 3 - 20MHz
49
18,4
0
0
0
0


156_LTE_3
E-UTRA Band 3 - 20MHz
49
18,4
0
0
0
0

[DANORM]

its all about relation between Pa Pb offset settings, rs power and total output power. Google the "LTE Downlink Power Allocation" documents and "Pa Pb offsets in LTE", it will make you clear about power allocation (you can find some docs on the forum also). Some formulas may be in "Technical Reference Guide" also but atoll is exactly copies the 3ggp standard about power allocation

[slava121]

Good afternoon, dear DANORM!
In Atoll, the concept of Pa, Pb is absent. Equivalent to the Pa - offset PDCCH, PDSCH, PBCH, SSS relative to the reference signal. Displacements can be understood as the values ​​of Pa, for example, in Wendor Huawei:


PA dB
3
2
1
0
-1.77
-3
-4.77
-6


This changes the values ​​of PDCCH, PDSCH, PBCH, SSS will change in the Cells Details table and in the LTE Cells table.
In Atoll, there are 5 modes of calculating RS EPRE:
1. Calculated (equal distribution of unused EPRE);
2. User defined;
3. Calculated (with boost);
4. Calculated (without boost);
5. Independent of max power
Which of the modes should be selected and which one is relevant?
It is not clear which formula is used to calculate the value of the reference signal.
In the training documents Huawei there is a formula:
RS Power = Total power per channel (dBm) - 10 * log (total subcarrier) + 10 * log (PB + 1) for the case with two antennas.
Regards

[slava121]

In the appendix, document 08 OEO107030 LTE eRAN6.0 Power Control Feature ISSUE1.00.
41528

Slava

[DANORM]

You can use that formula:

RS Power =ROUND(10*LOG10([each channel power(W)]*1000/([RB Num]*12*10^(PA(db)/10))),1)

I have that config Pa = -3 and Pb = 1 and atoll config

41529

[slava121]

Your formula, DANORM: RS Power = ROUND (10 * LOG10 ([each channel power (W)] * 1000 / ([RB Num] * 12 * 10 ^ (PA (db) / 10))), 1) interpreted differently:
RS Power = 10 * log (Pmax (Watt) * 1000) -10 * log (RB * 12) -log * 10 ^ (Pa (dB) / 10))
The formula can be interpreted differently, through the spectral density of the PSD.
The power of the reference signal is RS Power = PSD-Pa, where PSD = Pmax (dBm) -10 * log (RB) -10 * log (12), Pa = -3dB.
If we calculate by this formula, we also get PS Power = 15,2dBm
But how about Pb?

DANORM!
Why SS ERPE Ofset / RS = 0dB? It must be equal to PDSCH ERPE Ofset / RS /
What kind of payment mode do you have?


1.Calculated (equal distribution of unused EPRE);

2. User defined;

3. Calculated (with boost);

4. Calculated (without boost);

5. Independent of max power


Slava

[DANORM]

i have config-1

Pb not changing RS power level, its changing RE levels where RS elements are, so the Pa -3 and Pb 1 is the 100% utilization of your total power.

To be honest as i understand there is no Pb setting in atoll

[slava121]

DANORM!
Pb should affect the level of the PDCPCH EPRE signal?
Which hardware do you use?

[DANORM]

It will affect, I think so


DANORM!
Pb should affect the level of the PDCPCH EPRE signal?
Which hardware do you use?

[DANORM]

you can set "PDCCH Overhead (No. of Symbol Durations per Subframe)" in "Frame Configuration" in Network Settings

[slava121]

PDCCH can not be 0

[slava121]

Good day to all!
I found an explanation for my question. Formulas for calculating RS EPRE are presented in Atoll 3.3.2 Technical Reference Guide Radio. The formulas themselves look like this:

41538

41539

[slava121]

Good day to all!
I found an explanation for my question. Formulas for calculating RS EPRE are presented in Atoll 3.3.2 Technical Reference Guide Radio. The formulas themselves look like this:

41538

41539


41542

41541

41543

The first application, in fact Atoll 3.3.2 Technical Reference Guide Radio.part1. Why did it happen so I do not know.
Chapter 6.4 Calculation Details provides an explanation for all my questions.
I hope it will be useful not only for me.

With best regards, Slava.

P.S. In order to make it easier to download the manual I attach the link:
https://cloud.mail.ru/public/4Nns/F9A8RoUsj

[DANORM]

can you specify which are the offsets in that formula?

[slava121]

Good afternoon, DANORM!
When calculating the Reference Signal EPRE power, the offset is taken into account according to the formula in the picture!

41544

[Fran1234]

you can set "PDCCH Overhead (No. of Symbol Durations per Subframe)" in "Frame Configuration" in Network Settings

found this in the help i am a bit confused because i tought you can set only 3 DB extra depending on the amount of ports either on PBCH or PDCH
but it looks like i can set as much as i want on all the channels





Max power (dBm): The cell’s maximum transmission power. You can enter or modify this value if the RS EPRE option under the Advanced options on the Global Parameters tab of the LTE Network Settings folder’s Properties dialog box is set to any of the following:






•

Calculated (equal distribution of unused EPRE)






•

Calculated (with boost): This option corresponds to a 3 dB boost in the RS EPRE with 2 transmission antenna ports and 6 dB boost with 4 ports.






•

Calculated (without boost)






•

Independent of max power




The transmission powers corresponding to different channels are calculated using Max power, the energy per resource element offsets defined for the SS, PBCH, PDSCH, and PDCCH, and the number of resource elements corresponding to each channel, all of which are also calculated by Atoll.
Max power is calculated by Atoll from the user-defined RS EPRE value if the RS EPRE option in the Global Parameters of the LTE Network Settings folder is set to User-defined.


•

RS EPRE per antenna port (dBm): The reference signal energy per resource element. You can enter or modify this value if the RS EPRE option under the Advanced options on the Global Parameters tab of the LTE Network Settings folder’s Properties dialog box is set to User-defined or Independent of max power.




This value is calculated by Atoll from the user-defined max power value if the RS EPRE option under the Advanced options on the Global Parameters tab of the LTE Network Settings folder’s Properties dialog box is set to any of the following:


•

Calculated (equal distribution of unused EPRE)






•

Calculated (with boost): This option corresponds to a 3 dB boost in the RS EPRE with 2 transmission antenna ports and 6 dB boost with 4 ports.






•

Calculated (without boost)




For more information, see Global Network Settings.


•

SS EPRE Offset/RS (dB): The difference in the energy of a resource element belonging to the synchronisation signals with respect to the energy of a reference signal resource element. This value is used to calculate the transmission power corresponding to the primary and secondary synchronisation signals (PSS, SSS).






•

PBCH EPRE Offset/RS (dB): The difference in the energy of a resource element belonging to the PBCH with respect to the energy of a reference signal resource element. This value is used to calculate the transmission power corresponding to the physical broadcast channel (PBCH).






•

PDCCH EPRE Offset/RS (dB): The difference in the energy of a resource element belonging to the PDCCH with respect to the energy of a reference signal resource element. This value is used to calculate the transmission power corresponding to the physical downlink control channel (PDCCH).






•

PDSCH EPRE Offset/RS (dB): The difference in the energy of a resource element belonging to the PDSCH with respect to the energy of a reference signal resource element. This value is used to calculate the transmission power corresponding to the physical downlink shared channel (PDSCH).




Atoll first calculates the energy per resource element corresponding to the reference signal resource elements, the SS, PBCH, PDSCH, and PDCCH. Once the energies available for each of these resource element types are known, they are converted into transmission powers for further calculations. In the offset fields above, you must enter the offsets, i.e., the difference in the energy levels, for one resource element of each type. For example, if a resource element belonging to the SS has 3 dB less energy than a resource element of the downlink reference signals, you should enter -3 dB in the SS EPRE Offset. Atoll will then calculate the actual transmission power of the SS, i.e., all the resource elements of the SS, from this offset and the number of SS resource elements per frame.


•

Instantaneous RS power (dBm): The instantaneous reference signal transmission power calculated from the maximum power or RS EPRE and the EPRE offsets.






•

Instantaneous SS power (dBm): The instantaneous SS transmission power calculated from the maximum power or RS EPRE and the EPRE offsets.






•

Instantaneous PBCH power (dBm): The instantaneous PBCH transmission power calculated from the maximum power or RS EPRE and the EPRE offsets.






•

Average PDCCH power (dBm): The average PDCCH transmission power calculated from the maximum power or RS EPRE and the EPRE offsets.






•

Average PDSCH power (dBm): The average PDSCH transmission power calculated from the maximum power or RS EPRE and the EPRE offsets.




If the cell’s transmitter has a beamforming smart antenna equipment assigned to it, the transmission powers of the cell increase by http://www.finetopix.com/newreply.php?do=postreply&t=50754 (in dB), where n is the number of antenna elements of the beamforming smart antenna. This gain in transmission powers is referred to as the AAS power combining gain.

[Fran1234]

Good afternoon, DANORM!
When calculating the Reference Signal EPRE power, the offset is taken into account according to the formula in the picture!

41544


http://www.sharetechnote.com/html/Handbook_LTE_RSRP_EPRE_TotalPower.html