BG77 / CatM1 - Lock onto specific tower at command

Technical Subjects Software General Function
1

Hello,

I’m wondering if there’s an AT command to connect to a specific tower. We have a scenario where there’s two towers, both showing up as the same network provider in a remote area. One seems to transmit data for us fine and the other always fails and seems to screw up network searching. The provider has indicated that the tower that seems to have the issue is a tower provided by a third party for them that restricts some of their ability to debug.

To attempt to resolve that issue/keep debugging on my end I’d like to attempt to connect to the other working tower even if it has worse RSSI as a last ditch effort to get some sort of connectivity. Both towers are on the same band, so band locking doesnt work.

Something like AT+QNWLOCK looks like it might be what I’m looking for, but that command does not appear to be supported by the BG77.

2

Can you just lock to the provider you want by PLMN (MCC & MNC).

Eg: AT+COPS=1,2,"50502" for Optus AU.

1 Like
3

Thank you for the response!

Unfortunately I’m realizing I used network providers incorrectly in my question. Both towers show up as Verizon Wireless for us. I’ve already reached out to Verizon about this and they’ve indicated that while they have a third party contract for the seemingly problematic tower to show up as Verizon Wireless, it’s not their tower in the same way that the working tower is, which is apparently hindering their ability to get proper network logs for either them or us to figure out the issue.

I’ll edit my post to make it more clear.

Edit: I’ve updated the original post.

4

Maybe you can still provider-lock to get the cell you want. In my list of PLMN codes published by the ITU, I find all of these allocated to Verizon within the USA:

310010
310012
310013
310350
310590
310820
310890
310910
311110
311270 through 311289 without any gaps
311390
311480 through 311489 ditto
312770

While I’m sure not all are in use, you might be lucky.

5

Have you tried the test syntax: AT+QNWLOCK=?

6

Yeah the module returns ERROR. I’m on BG77LAR02A04_011.005.01.005 which isnt the newest software, but I dont see anything in the release notes about it being added to any of the newer revisions.

I also have a BG770A and the test code for that returns ERROR as well.

I haven’t seen any reference to that command getting used for the catm1/nbiot modules.

I appreciate the suggestion though!

7

My BG96:

ATI
Quectel
BG96
Revision: BG96MAR02A07M1G
OK
AT+QNWLOCK=?
+QNWLOCK: "common/4g",<num of cells>,[[<freq>,<pci>],...]
OK