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Measuring RSRP in 5G

Started by dgshaw6 6 days ago1 replylatest reply 6 days ago77 views

Hi all,

In the 3GPP standard 38.215 Section 5.1.19, there is a reference to the definition of the RSRP for SRS.
It appears to simply be the average of the power in the occupied bins/elements containing SRS.
In the MatLab 5G Toolbox, there is a test example for CSI-RS RSRP measurement, but all the values generated and measured are very small IQ values for elements in the rxGrid. (O(1e-6) for the reference of -97 dBm)

I am trying to figure out how I find the scaling that tells me how to map the integer IQ values that I get from the RU, to the correct mapping to match the requirements of the testing process from the standard mentioned.

Any help gratefully accepted.

David

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Reply by kazJune 21, 2022

In a general sense a digital power needs to be referenced to a given point for example antenna receiving signal. Any gain between antenna and SRS is implementation dependent and needs to be known for example your ADC, filters, AGC, FFT. The ADC data should tell relation between dB and dBm.

Then you reference power back accordingly. I expect FFT transfer to be less obvious since unity gain does not mean unity exactly due to discarding noise bins but I am not sure if this is defined in the standards.