In an RG530F-EU module we are trying to attach in 5G Standalone (SA) to a private mmWave n257 (28 GHz band, TDD) cell. The module camps on the cell and reads SSB/SIB1 (LIMSRV), but never transmits any uplink — AT+QNWCFG="nr5g_tx_pwr" stays 0 the whole time, so the module never sends a PRACH / never initiates random access, and therefore never registers or establishes a PDU session. The same module and SIM register and work fine on n78 (FR1) SA.
This matches your forum threads [#55114] and [#40155]: n257 SA is not enabled in the RG530F-EU firmware (n257 is supported in NSA only) and requires a Quectel-provided MBN profile + FR2-SA configuration/firmware to unlock.
We are requesting:
- The FR2 SA MBN profile and any firmware required to enable n257 (and/or n261) 5G SA on RG530F-EU for our firmware version.
- The FR2 SA Application Note for RG530F.
- Confirmation of which mmWave bands (n257 / n258 / n260 / n261) are supported for SA (standalone) vs NSA on this module, and the correct provisioning steps.
2. Module / firmware
ATI:
Quectel
RG530F-EU
Revision: RG530FEUEAR05A02M8G
- Variant: RG530F-EU
- Connection: USB, MBIM mode (wwan), AT port /dev/ttyUSB2
- SIM: test SIM, IMSI 001010000012257, PLMN 001/01 (private network)
3. Network under test
- Private 5G SA network, band n257, TDD, SCS 120 kHz, 100/200 MHz.
- SSB @ ARFCN 2065051 (27.153 GHz); also tried ARFCN 2079739 (28.034 GHz).
- gNB: OpenAirInterface (OAI) + O-RAN 7.2 mmWave O-RU. 5GC: OAI/Open5GS.
- The same gNB/UE/SIM on n78 (FR1) SA registers successfully (see §5), so the SA core, SIM provisioning and the module’s SA/TX chain are all functional — the problem is specific to n257 SA uplink.
4. UE configuration applied (per your FR2 setup guidance)
AT+QMMWENABLE=1 -> OK (mmWave front-end enabled)
AT+QNWPREFCFG="mode_pref",NR5G -> OK (NR5G only / SA)
at+qnvfw="/nv/item_files/modem/nr5g/RRC/fr2sa_enabled",01 -> OK
AT+QNWPREFCFG="nr5g_band",257 -> OK (accepted; no CME ERROR)
AT+QNWPREFCFG="nr5g_disable_mode",0 -> OK (SA+NSA)
AT+QMBNCFG="autosel",0 -> OK
AT+QMBNCFG="select","ROW_Commercial" -> OK
AT+CGDCONT=1,"IPV4V6","oai" -> OK
AT+CFUN=1,1 (hard reset)
Capability report:
AT+QNWPREFCFG="ue_capability_band"
+QNWPREFCFG: "nsa_nr5g_band",1:3:5:7:8:20:28:38:40:41:75:76:77:78:257:258:260:261
+QNWPREFCFG: "nr5g_band",257
(n257/n258/n260/n261 all listed under nsa_nr5g_band.)
5. Observed behaviour
On n257 (FR2) — FAILS: camps but never transmits UL
While the gNB is transmitting and the module is camped, polling every ~2 s:
state=LIMSRV RSRP=-65 dBm AT+QNWCFG="nr5g_tx_pwr" -> 0
state=LIMSRV RSRP=-70 dBm AT+QNWCFG="nr5g_tx_pwr" -> 0
state=LIMSRV RSRP=-77 dBm AT+QNWCFG="nr5g_tx_pwr" -> 0
... (nr5g_tx_pwr = 0 for the entire session, at all RSRP levels)
AT+C5GREG? -> +C5GREG: 0,2 (searching / not registered)
AT+QENG="servingcell"
+QENG: "servingcell","LIMSRV","NR5G-SA","TDD",001,01,000000001,0,1,2065051,257,13,-65,-11,...
AT+CGPADDR=1 -> +CGPADDR: 1,"0.0.0.0" (no PDU / no IP)
- The module camps on the correct NR5G-SA cell (PLMN 001/01, ARFCN 2065051, band 257) and reports good RSRP (down to −58/−65 dBm), but stays in LIMSRV (limited service).
nr5g_tx_pwr= 0 at all times → the module never keys the UL transmitter → no PRACH.- gNB confirms: no PRACH preamble is ever received (UL is at the thermal-noise floor whether the module radio is ON or OFF), i.e. the module is not transmitting Msg1.
- Result: no random access → no registration → no PDU session → no IP.
On n78 (FR1) — WORKS
Same module + SIM + core on band n78 (sub-6 GHz) SA: Registration Complete, UE reaches 5GMM-REGISTERED at the 5GC. So SA registration and the module’s UL transmit path work — the failure is confined to n257 SA uplink.
6. Our interpretation (please confirm)
The RG530F-EU firmware (RG530FEUEAR05A02M8G) appears to enable n257 in NSA only; in SA the module camps for limited service but will not initiate random access on n257 (uplink stays disabled, nr5g_tx_pwr=0). This is consistent with forum threads #55114 and #40155, where Quectel indicated an MBN profile + FR2-SA files/firmware are required to enable n257 SA.
7. Questions
- Is n257 5G SA supported on RG530F-EU with firmware RG530FEUEAR05A02M8G? If not, which firmware version enables it, and can you provide it?
- Please provide the FR2 SA MBN profile (and the FR2 SA Application Note) to enable n257 (and/or n261) SA uplink on this module/firmware.
- Which mmWave bands are supported for SA vs NSA on RG530F-EU? Is n261 (US 28 GHz) SA-capable out of the box, as an alternative to n257?
- Are there additional NV items / AT settings (beyond
fr2sa_enabled=01,mode_pref=NR5G,nr5g_band,nr5g_disable_mode=0) required to make the module perform SA random access on mmWave?