[srsran-users] Unable to find the ENB 4G network using u-blox SARA-R422S-01B-00 modem

[sobol6803 at gmail.com]

Hi,

Thank you for responding! I have since moved on to 2G, at least until I 
switch to a different modem. Is "LTE Cat 1 bis" supported by srsRAN 4G?

On 2024-02-09 16:18, Robert Falkenberg wrote:
> Hi,
>
> the modem seems to only support "LTE Cat M1", "LTE Cat NB2", "2G GPRS 
> / EGPRS".
> I can't see it supporting plain LTE.
>
> (Also note Cat M1 is 1.4MHz, whereas the config you posted has 
> "n_prb=15" = 3MHz.)
>
> Best regards,
> Robert
>
> On 07.02.24 18:47, sobol6803 at gmail.com wrote:
>>
>> Hello,
>>
>> My current configuration:
>>
>>   * EPC and ENB runs on Intel i5-9400 (all cores in performance
>>     mode), Ubuntu Server 22.04.3 LTS (kernel 5.15.0-92-generic)
>>   * UE's: an Android tablet and a custom device with u-blox
>>     SARA-R422S-01B-00 modem (3GPP Release 13 LTE Cat M1)
>>   * Ettus USRP B210 with all 4 antennas connected, external power, no
>>     external clock
>>   * sysmocom sysmoISIM-SJA5-9FV sim cards
>>
>> Everything works on the Android tablet - I can find my network and 
>> connect to it. The 4G works and so does the internet.
>>
>> But the SARA modem cannot even find the network. It can read the 
>> sysmocom sim card (CCID, preferred MCCMNC), it works with other 
>> commercial sim cards (and their corresponding networks), but it just 
>> will not find my custom 4G network. I have tried to modify the IMSI 
>> and preferred MCCMNC of the sim card from the default 99970 to one of 
>> a commercial network from another country, but it did not help 
>> (worked on the tablet though).
>>
>> Sending "AT+COPS=?" to the modem returns only commercial networks in 
>> range.
>> Sending "AT+COPS=1,2,"MCCMNC",7" returns "+CME ERROR: no network 
>> service" and both EPC and ENB logs do not show any connection attempts.
>>
>> Current configuration:
>>
>> # epc.conf
>> [mme]
>> mme_code = 0x1a
>> mme_group = 0x0001
>> tac = 0x0007
>> mcc = 999
>> mnc = 70
>> mme_bind_addr = 127.0.1.100
>> apn = srsapn
>> dns_addr = 8.8.8.8
>> encryption_algo = EEA0
>> integrity_algo = EIA1
>> paging_timer = 2
>> request_imeisv = false
>> lac = 0x0006
>>
>> # enb.conf
>> [enb]
>> enb_id = 0x19B
>> mcc = 999
>> mnc = 70
>> mme_addr = 127.0.1.100
>> gtp_bind_addr = 127.0.1.1
>> s1c_bind_addr = 127.0.1.1
>> s1c_bind_port = 0
>> n_prb = 15
>> tm = 2
>> nof_ports = 2
>> [rf]
>> dl_earfcn = 1934
>> tx_gain = 80
>> rx_gain = 40
>> device_name = UHD
>> device_args = auto
>>
>> # user_db.csv (anonymized)
>> sim1,mil,999701111111111,11111111111111111111111111111111,opc,11111111111111111111111111111111,9000,000000000464,9,dynamic
>>
>> Everything else is default.
>>
>> Do you know what could be the problem? Is the ENB misconfigured, or 
>> is the modem somehow incompatible with my network?
>>
>> _______________________________________________
>> srsran-users mailing list
>> srsran-users at lists.srsran.com
>> https://lists.srsran.com/mailman/listinfo/srsran-users
>
> -- 
>
>
>       RobertFalkenberg
>
> Senior Engineer
>
> Software Radio Systems
>
> 	
> 	
> 	
> 	
>
> 	robert at srs.io <mailto:robert at srs.io>
>
> 	www.srs.io <//www.srs.io>
>
> 	Dortmund, Germany
>
>
>
>
> 	
> twitter <https://twitter.com/srssystems> 	
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://lists.srsran.com/pipermail/srsran-users/attachments/20240215/abacaab3/attachment.htm>