Need for 5G NR RSRQ,RSRP, SINR details

IoT Modules 5G Module
1

Hi,

Could you please answer to these two questions for a RM502Q-AE?

  • Are RSRQ, RSRP and SINR given by AT+QENG an average of the values measured at each antenna?

  • What reference signal is used by RM502Q-AE to calculate RSRQ, RSRP and SINR in 5G nr (CSI, SSS, …) ?

Thank you

2

Helo
The answer of your first question is Maximum RSRP value can be calculated based on maximum input UE power UE which is -25 dBm and minimal LTE bandwidth which is 1.4 MHz, i.e. 72 resource elements . Then -25 - 10*LOG(72) = -44 dBm. Absolute RSRP measurement accuracy is between ±6 and ±8 dB.
(2) In LTE, the UE measurements are done for RSRP, RSRQ and SNR associated with CRS (Cell Specific Reference Signal) . 5G NR uses SS (Synchronization Signal) and CSI (Channel State Information) instead of CRS, so 3GPP had put new definitions for UE measurements in place.
Best regards

Inayat

3

Hi,
Tank you for your reply.

I agree that we can calculate the RSRP from the RSSI and the bandwidth. I also agree that 5G uses SS and CSI as references.

But my questions were more about:

  • How does the modem caluclate the RSRQ, RSRP and SINR given by AT+QENG with multiple antennas? Does it calculates an average value? Does it take the values of the antenna with the best RSRP?

  • The AT Commands Manual for RM5xxQ Series does not specifies if the RSRQ, RSRP and SINR are SS-RSRQ, SS-RSRP and SS-SINR or CSI-RSRQ,CSI-RSRP and CSI-SINR. How to know which one is given by the modem?

Best regards

4

My experience leads me to believe that +QENG reports signal data from the main antenna.

You can read signals from all four antennas, where the RAT (LTE or NR5G) is reported:

AT+QRSRP
+QRSRP: -114,-115,-140,-140,LTE
OK
AT+QRSRQ
+QRSRQ: -17,-16,0,0,LTE
OK
AT+QSINR
+QSINR: 9,6,-20,-20,LTE
OK
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