How do I get signal strength for RM500Q?

IoT Modules 5G Module
1

Hello, I am using an RM500Q-GL 5G module connected to a Khadas Vim 4 board running Ubuntu 22.04. To connect, I am compiling quectel-CM by following the instructions here without problems.

Once I have connected how can I get signal strength (either from the command line or programmatically through python)?

Thanks.

2

Dear @Andreas_Gazis
You can use AT+QENG=“servingcell” to query. Detailed information please refer to the document which I sent to you via Message, please check.

3

Thanks. There appears to be an error in the documentation for AT+QENG . According to page 104, the response for AT+QENG=“servingcell” in EN-DC mode should be of the form:

+QENG: "servingcell",<state>
+QENG: "LTE",<is_tdd>,<MCC>,<MNC>,<cellID>,<PCID>,<earfcn>,<freq_band_ind>,<UL_bandwidth>,<DL_bandwidth>,<TAC>,<RSRP>,<RSRQ>,<RSSI>,<SINR>,<CQI>,<tx_power>,<srxlev>
+QENG: "NR5G-NSA",<MCC>,<MNC>,<PCID>,<RSRP>,<SINR>,<RSRQ>,<ARFCN>,<band>,<NR_DL_bandwidth>,<scs>

That is, three lines starting with +QENG.
The first two lines conform to the description, however, the third line (starting with +QENG: “NR5G-NSA”) should be followed by 10, comma separated values. I only get 6, example output:

+QENG: "NR5G-NSA",240,02,65535,-32768,-32768,-32768

Do you know why I am seeing this discrepancy and what the values returned correspond to?

4

Dear @Andreas_Gazis
+QENG: “NR5G-NSA”,240,02,65535,-32768,-32768,-32768
=>65535,-32768,-32768,-32768 are invalid values, it didn’t register to 5G.
Could you help to check AT+COPS? and AT+C5GREG? to query the status?

5

It connects somehow because I can ping the outside world over the modem’s interface.
Results of the commands you listed:

AT+COPS?
+COPS: 0,0,"hallon hallon",7

OK

and

AT+C5GREG?
+C5GREG: 0,0

OK

I also did the following:

AT+CREG?
+CREG: 0,1

OK

and

AT+CGREG?
+CGREG: 0,0

OK

and

AT+CEREG?
+CEREG: 0,1

OK

Hope this helps.

6

Dear @Andreas_Gazis
The device has registered on LTE, not 5G. So you saw the invaild values.

7

I see. But if I am connecting in LTE mode, why doesn’t AT+QENG=“servingcell” return the LTE mode response as described on page 104 of the manual, i.e.:

+QENG: "servingcell",<state>,"LTE",<is_tdd>,<MCC>,<MNC>,<cellID>,<PCID>,<earfcn>,<freq_band_ind>,<UL_bandwidth>,<DL_bandwidth>,<TAC>,<RSRP>,<RSRQ>,<RSSI>,<SINR>,<CQI>,<tx_power>,<srxlev>

At the moment, it returns the EN-DC response, containing a third line starting with: +QENG: “NR5G-NSA”

8

Hi @Andreas_Gazis,

you will typically see a “short” “NR5G-NSA” line when ENDC is available but no NR resources have been assigned to the UE by the network at the moment. HTH for clarification.

Regards,
Reinhard

9

Thanks. So, to recap, to see signal quality I can look at the RSSI and SINR in the response to AT+QENG=“servingcell”.

What about connection type though (3G, 4G, 5G etc)? Where is the definitive place to look for it?