RM500Q-GL does not aggregate LTE carriers

Just received a RM500Q-GL module and to my dismay it does not aggreate carriers - it always uses only one of the available bands (my tower is 4CA capable) - how comes? The specs says this module is CAT20 and can go up to 7CA!!

Firmware is RM500QGLABR10A01M4G

Normally CA is not active, you have to be transferring continuous data like downloading or streaming video.
First start watching any YouTube video, then send these commands while still streaming to see the CA info:

AT+QCAINFO
AT+QNWINFO
AT+QENG=“servingcell”

Hey Bill, Rick here, we exchanged emails recently :slight_smile:
I normally run a speedtest , either on the laptop or using rooter’s netperf based one.
Both should trigger a CA. They do on my EG12 based Mikrotik Chateau.
Also, other people on this forum is saying the same.

Have you been able to see the QCAINFO report something with this modem in your tests?

Thanks
Rick

The QCAINFO command should be universal for all Qualcomm chipsets, however I just read one of the posts from a Quectel engineer that Qualcomm hasn’t released the 5GNR commands for some strange reason. On the other hand I’ve seen some undocumented 5G specific commands found by some members on the Whirlpool forum for both Quectel and Simcom 5G modems (the commands should be interchangeable).
You may want to check it out at > https://forums.whirlpool.net.au/thread/3vx1k1r3

I have installed the libqmi and qmicli tool on my router and I can see that the modem IS actually aggregating!
Example:

Every 1.0s: qmicli -d /dev/cdc-wdm0 -p --nas-get-lte-cphy-ca-info                                                      Fri Sep 25 15:18:10 2020

[/dev/cdc-wdm0] Successfully got carrier aggregation info
DL Bandwidth: '10'
Primary Cell Info
        Physical Cell ID: '273'
        RX Channel: '3350'
        DL Bandwidth: '20'
        LTE Band: 'eutran-7'
Secondary Cell 1 Info
        Physical Cell ID: '400'
        RX Channel: '150'
        DL Bandwidth: '10'
        LTE Band: 'eutran-1'
        State: 'activated'
        Cell index: '1'
Secondary Cell 2 Info
        Physical Cell ID: '400'
        RX Channel: '1650'
        DL Bandwidth: '20'
        LTE Band: 'eutran-3'
        State: 'activated'
        Cell index: '2'

So, what is actually broken is the AT+QCAINFO which does not return anything.

Nice job… as we talked about it, the QCINFO is not yet or wrongly implemented by Qualcomm.
This is what happens when rushing products to market.
Now the big question is, will it display the CA info in 5G mode, since you can only test it in 4G-LTE.

I think all the development effort in this module is on the 5G, so I bet it will in that mode.
Yes no 5G here yet (at least where I live).

Dear Rick,
RM500Q-GL can support LTE 3CA, RM502Q can support LTE 5CA.
Can you tell your company name, we will ask local FAE to support.

The preliminary sheet for RM500Q says this is a CAT16 LTE modem, and therefore should support 4CA not 3CA. Do you have the “official” sheet with all the CA combinations supported by RM500Q in LTE mode?

Thanks
Rick

of course, please tell your company name and e-mail address, we will send to you.thanks.

can you please send me that document to me too? thanks

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