How do I band lock and carrier aggregate?


I have a RM500Q-GL and I’m trying to enable carrier aggregation manually with band locking (LTE). I have the manual for this module but i can’t seem to find out how to do it. Carrier aggregation doesn’t seem to function currently even though I have 100% signal strength and another band available on the tower.


Have you solved your problem? Are you 100% sure it is not aggregating? I’m waiting for an RM500Q-GL as well and am a bit worried.

Hi Rick, no I haven’t. I do not recommend this modem unfortunately. I know I’m not aggregating and there isn’t a way to manually band lock in the documentation unlike other quectel modems. Additionally, I know my tower has 5G bands, yet my modem isn’t connecting to any of them. I’m using rooter firmware on a router to host the modem. You’ll see that this 5G issue is a problem across other posts in this forum. I should have gone with a EM20G or something like that. I’m unhappy I took the plunge on such a untested, expensive modem.

There’s obviously no help from Quectel here either.

Does at least show you what band it is connected to? I do have the manual (not the unit yet) I’ll have a look. I also will be running it with the rooter software…

I am having the same issue with my engineering sample. There are 5G bands available (5G phone connects and gets 300 to 500Mbps download), but the RM500Q-GL does not connect to 5G, and the download is around 120Mbps. If anyone has any advice that could help get it working on 5G it would be appreciated. I have tried it with ModemManager and Quectel-CM with the qmi_wwan_q driver. That said, it may not be specific to Quectel, because the 5G SIMCOM module I have also exhibits the same behaviour.

From the manual:

AT+QNWPREFCFG=“lte_band”[,<LTE _band>]
AT+QNWPREFCFG=“nsa_nr5g_band” [,<NSA_NR5G_band>]

These can be used to lock one or more bands (4G or 5G)

Are you saying these do not work?

Addendum - module arrived.
I can actually decide which bands to consider with the command I posted above.
I cannot lock to a specific PCID unlike the LTE series of quectel modules, which is bad bad bad,

@fidelis can you please post here your modem revision as shown with the ATI command? Thanks

My modem is correctly aggregating, but does not report it in the QCAINFO command. Just FYI

Dear Fidelis,
could you tell me which firmware did you test? now the latest firmware can support to query CA on LTE by AT+QCAINFO

I’m using an older firmware version: RM500QGLAAR01A01M4G_BETA_20200330F

Can you send me the latest version, and instructions on how to update it?

Thank you

RM500QGLAAR01A01M4G is ES(engineer sample) sample, it is too old. please use CS2 sample to test. The order code is RM500QGLAB-M20-SGASA. By the way, ES sample can not upgrade CS2 firmware.thanks!

Hi Peter, thanks for the response. Are there any options at upgrading the firmware? I know you said you can’t but why is that? Are there physical differences? Can you please reach out to your engineers and see if there’s any way? Thank you

Hello, I have confirmed ES samples can not upgrade CS software, because of the hardware differences.thanks!

While talking to a Tmobile engineer in the US, I was told that in NSA (Non-Stand-Alone) mode, the tower can instruct the modem to stay in LTE modem and only engage 5G when it senses large amounts of data transfer. So it’s not unusual for the modem to idle in LTE mode till it’s instructed. In other countries which use SA (Stand-Alone) mode the modem will normally stay in 5G mode all the time. I cannot confirm the accuracy of this, but does make sense.
This is probably why the “-GL” global model which doesn’t have NSA mode on most US bands (missing NSA on n2/5/66/71 only has it on n41 according to initial specs, unless it has been changed in the firmware), doesn’t work well 5G mode in the US, while the “-AE” model does since it has NSA mode on all US 5G bands.


Hello,Bill,yes, it is true, and in America market, RM500Q-AE will be better.