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I use RUTX09 with RUTX_R_00.02.06.01 FW.
I connect to an LTE BTS providing B28, B20 and B3. I get a very bad issue when B20 and B28 allowed at the same time.
When I select "auto" band selection or when in manual band selection I have both B20 and B28 selected, B28 cells never appear in neighbour cells (gsmctrl -I).
As soon as I use manual band selection and get B20 unselected, B28 cells appears in neighbour cells as expected.

As a consequence the best B28 cell is never used by the modem when B20 is selected regardless the closest B28 cells offer generally a significantly better radio link than the B20 ones.
And unfortunately manual B3 + B28 manual selection is not a workaround, as I then face to another issue where all B28 cells disappear after some time with no more possible carrier aggregation with B3, and I need a modem reset to get B28 reappear and getting B28+B3 carrier aggregation again, see the issue depicted here.

Following are some console captures to illustrate issue with B20+B28 selected at the same time. I just performed some gsmctl commands to print serving cell SINR, visible cells list and serving cell data:

I select in web UI "auto" band selection => no B28 cells visible and B20  PCI 404 selected as serving cell:

root@Teltonika-RUTX09:~# gsmctl --sinr ;gsmctl -I; gsmctl -K
3.5
+QENG: "neighbourcell intra","LTE",6400,404,-9,-96,-68,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,29,-18,-109,-78,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,45,-18,-109,-74,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,26,-19,-109,-74,0,-,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,230,-11,-116,-82,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,327,-18,-125,-97,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,143,-20,-125,-97,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,491,-20,-125,-97,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,14,-20,-125,-95,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,115,-20,-127,-96,0,-,-,-,-
+QENG: "servingcell","NOCONN","LTE","FDD",208,01,EDFA04,404,6400,20,3,3,3943,-96,-9,-71,13,-

Right after I select all bands except B20 => now B28 cells are there (and PCI 164 is very good !) and B28 PCI 164 selected as serving cell:

root@Teltonika-RUTX09:~# gsmctl --sinr ;gsmctl -I; gsmctl -K
11.5
+QENG: "neighbourcell intra","LTE",9310,164,-7,-98,-71,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",9310,366,-18,-108,-80,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",9310,186,-19,-113,-84,0,-,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,230,-7,-112,-83,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,327,-20,-127,-98,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,143,-16,-122,-98,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,48,-20,-125,-95,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,491,-20,-127,-98,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,0,0,0,0,0,-,-,-,-
+QENG: "servingcell","NOCONN","LTE","FDD",208,01,EDFA01,164,9310,28,3,3,3943,-98,-7,-73,16,-

Then selecting B3+B20+B28 => once again no B28 cells anymore and B20 is selected as serving cell:

root@Teltonika-RUTX09:~# gsmctl --sinr ;gsmctl -I; gsmctl -K
5.3
+QENG: "neighbourcell intra","LTE",6400,404,-10,-96,-67,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,45,-16,-105,-78,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,29,-20,-108,-77,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,202,-20,-108,-79,0,-,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,230,-9,-111,-81,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,327,-17,-124,-97,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,115,-16,-121,-96,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,14,-19,-125,-96,0,-,-,-,-
+QENG: "neighbourcell inter","LTE",1300,143,-20,-126,-97,0,-,-,-,-
+QENG: "servingcell","NOCONN","LTE","FDD",208,01,EDFA04,404,6400,20,3,3,3943,-96,-10,-70,12,-

Selecting only B20+B28 => still no B28 cells are visible and B20 is selected as serving cell:

root@Teltonika-RUTX09:~# gsmctl --sinr ;gsmctl -I; gsmctl -K
4.1
+QENG: "neighbourcell intra","LTE",6400,404,-11,-98,-69,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,45,-19,-108,-79,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,202,-20,-107,-78,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,29,-19,-107,-77,0,-,-,-,-,-
+QENG: "neighbourcell intra","LTE",6400,336,-18,-106,-77,0,-,-,-,-,-
+QENG: "servingcell","NOCONN","LTE","FDD",208,01,EDFA04,404,6400,20,3,3,3943,-98,-11,-67,11,-

Anyone having same issue or any workaround ?

1 Answer

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Hello,

Is this thread related to your other one: https://community.teltonika-networks.com/32467/another-selection-issue-with-leading-rutx09-router-becomes  ?

It would be nice if you keep related information in a single thread. I am investigating your latest issue.

Regards.

by

Hi,
The relationship between both thread is B28 management issue in modem.

However if both issues can be related, at this point it is not clear they have same root cause and this is te rational to have created a 2nd thread to not mix evrything but nevertheless taking care to refer each one to the other one to keep track of the relationship.
In this one, the point is when B20 selected, B28 cells are never visible and never use by the modem (while B28 performs better than B20).
In the second one (https://community.teltonika-networks.com/32467/another-selection-issue-with-leading-rutx09-router-becomes), the issue is when B28 is used with B3 (and then of course to have this happens I need to prohibit B20 selection), there is a point in time wher B28 cells are no more visible in neighbour cells and then never used anymore until modem is restart.

I thought this may help to separate both issues, especially this one is very easy to reproduce (at least at my side) as systematic and independant of radio condition (however need to have B20 and B28 simultenaously), while other one is more complicated to reproduce, e.g. at my side it can take up to 1 day to get it happen and I think it depends from relative radio condition between B3 and B28 (but not proven yet).

Whatever, if you prefer to keep evrything in the same thread I have no issue with this and I can close this one. Please let me know what is your preference.
YB

by

I will not continue this thread anymore. Please refer to this one which includes all the information: cat6 rutx09 router becomes only cat3 with B3+B28 band selection