Issue with connecting to different networks

IoT Modules MC/EM Series
1

I have an EM9293 and a 5G/LTE sim card inserted. For some reason, it never connects to 5G or LTE. It’s stuck in WCDMA. For a different carrier’s SIM card, I can only get LTE connection, not 5G or 3G. I’m sure that I have 5G, 4G, and 3G service in the area for those carriers.

For reference, I used AT+COPS=? which allows me to see all the available operators (3g, lte, 5g for various carriers) but when I try to select them, it says no service (except one of them which works). Also, I tried forcing it by using AT!SELRAT=

I have tried updating firmware to the specific carrier, tried on both Windows and Raspberry Pi, and tried on both EM9191 and EM9293 modems. Is the issue with the modem or something else?

2

Did you check at!band?

Also you can check at!sdpref? To see what band is supported

I remember if there is no data traffic, it might stay in lte mode instead of 5g mode

3

Yes, I’ve checked AT!BAND and tried variations of setting it to All Bands or just 3G, or 4G, or 5G, etc.
This is AT~SDPREF?:

AT!SDPREF?
RATs : WCDMA,LTE,NR5G
GWC  : B1,B2,B4,B5,B6,B8,B19
LTE  : B1,B2,B3,B4,B5,B7,B8,B12,B13,B14,B17,B18,B19,B20,B25,B26,B28,B29,B30,B32,B34,B38,B39,B40,B41,B42,B43,B46,B48,B66,B71
TDS  : 
NRSA : n1,n2,n3,n5,n7,n8,n12,n13,n14,n18,n20,n25,n26,n28,n29,n30,n38,n40,n41,n48,n66,n70,n71,n75,n76,n77,n78,n79
NRNSA: n1,n2,n3,n5,n7,n8,n12,n13,n14,n18,n20,n25,n26,n28,n29,n30,n38,n40,n41,n48,n66,n70,n71,n75,n76,n77,n78,n79

It could be data traffic, since when I tested the sim cards on a phone, they connect to the different networks. How can I get that data traffic on my PC (raspberry pi or Windows)?

4

If you are using mbim mode, there should be user interface in windows to connect cellular network

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image1012×1569 91.1 KB

For linux, you can use mbim-network

5

I will try and help. I see two different problems.

1 - WCDMA problem - I think what is happening here, the SIM + module is trying to register on LTE but getting rejected and then the module goes to WCDMA mode.

2 - not getting 5G service - you have to browse the web, meaning generate traffic and then the network will hand up to 5G because you need it based on your traffic profile.

6

On Windows user interface, it says 5G but I did AT!GSTATUS which showed that it was still in LTE. Using the internet or pinging doesn’t seem to force it to 5G.

7

Yes, I think it keeps getting rejected on LTE (and 5G) for the sim that only works on 3G. And for the sim that only works on LTE, I think it’s getting rejected on 5G (and 3G) for some reason.

8

then maybe your SIM card can only register LTE.

9

But for the sim that only connects to WCDMA on the EM9293, I tried on my phone and LTE worked.

10

did you connect 4 antennas?

BTW, did you set up the correct APN in AT+CGDCONT?

11

Thank you very much, those two steps did it. Quick question for AT+CGDCONT, is there a way so that I can add two profiles (1 for each sim)? Because right now when I switch sims using AT+UIMS, I have to set up the correct APN again.

12

I think you need to set up apn in profile 1 again whenever switching sim