[GL-XE3000] Low and Unstable 5G NSA Throughput – Possibly Due to Limited 10 MHz LTE Bandwidth

Hello GL.iNet Support,

I'm using a GL-XE3000 (Spitz AX) router with the following setup and have encountered unstable and significantly lower throughput than expected when connected to a 5G NSA tower.

Device Info

  • Model: GL-XE3000 (Spitz AX)
  • Modem: Quectel RM520N-GL
    • FW: RM520NGLAAR03A03M4G
  • Firmware: 0704release5
  • Carrier: Orange Romania
  • SIM: Orange SIM in Slot 1

Configuration Steps Performed

  1. Band masking enabled in the GUI:
  • LTE bands selected: B1, B3, B7, B20
  • 5G NSA band selected: n1
  1. Also tested with various AT commands directly:
AT+QNWPREFCFG="lte_band",1:1,3,7,20
AT+QNWPREFCFG="nr5g_band",1:1
AT+CFUN=1,1

Verified 5G NSA and Carrier Aggregation is active:

AT+QCAINFO
+QCAINFO: "PCC",1600,100,"LTE BAND 3",...
+QCAINFO: "SCC",429610,1,"NR5G BAND 1",...
  • This confirms:
  • NSA connection is active
  • NR band n1 is aggregated
  • Ran speed tests via speedtest.net and iperf3.

Observed Behavior

Despite perfect signal (RSRP -67, SINR 13+, NR RSRP ~ -61), speeds remain low and unstable
Throughput fluctuates heavily between 15–60 Mbps, with rare bursts up to 120 Mbps.
AT+QCAINFO consistently shows LTE Band 3 operating at **10 MHz bandwidth.
Even during active downloads, Carrier Aggregation appears only briefly and **doesn't improve throughput consistently.
iPhone connected to the same tower (Band 3 + n1 NSA) consistently reaches 130–160 Mbps.

Analysis

  • It appears that the modem is limited to 10 MHz bandwidth on Band 3 (despite Band 3 normally supporting up to 20 MHz).
  • The modem does not aggregate other LTE bands (like Band 7), even though they are enabled and used by Orange.
  • NR Band n1 is active, but offers only limited bandwidth (likely 10 MHz), and does not compensate for the LTE bottleneck.
  • CPU and system resources are not the issue (95% idle).
  • Multiple attempts with LTE+NSA band combos and restarts yield the same results.

Request for Clarification / Help

  • Is there a known limitation or configuration in the RM520N-GL or GL-XE3000 firmware that restricts LTE Band 3 to 10 MHz only?
  • Can the device be forced to use 20 MHz on LTE Band 3, or to aggregate LTE Bands (e.g., B3 + B7)?
  • Is there any newer firmware (router or modem) that improves 5G NSA behavior or CA activation?
  • Would enabling 5G SA provide better stability/performance, and is this supported in the UI?

Thank you!

More evidence:

:page_facing_up: Additional Evidence: Vodafone SIM (Same Router)

When testing with a Vodafone Romania SIM, the same router and modem deliver significantly better and more stable performance:

:bar_chart: Speed Test via iPerf3

  • Average: 96 Mbps
  • Max: 198 Mbps
  • Min: 54 Mbps
  • Test Duration: 5 minutes, 5 streams

:page_facing_up: AT+QCAINFO Output on Vodafone:

text

CopyEdit

+QCAINFO: "PCC",1400,100,"LTE BAND 3",1,387,-74,-13,-42,6
+QCAINFO: "SCC",1256,50,"LTE BAND 3",2,1,-70,-12,-40,12,0,-,-
+QCAINFO: "SCC",500,50,"LTE BAND 1",2,355,-65,-12,-40,18,0,-,-
+QCAINFO: "SCC",6250,50,"LTE BAND 20",2,288,-51,-13,-21,14,0,-,-

OK

:white_check_mark: Carrier Aggregation is fully active:

  • 3x LTE SCCs (Band 3, Band 1, Band 20)
  • 50 MHz total aggregated bandwidth
  • Consistent throughput near 100–200 Mbps

:mag: Conclusion:

  • Confirms the router, firmware, and modem are functioning as expected.
  • Indicates that Orange Romania likely limits LTE Band 3 to 10 MHz and does not enable LTE CA on this tower/SIM profile.
  • Vodafone proves the hardware can easily exceed current Orange performance.

Based on > Orange Romania 5G - NR, 4G - LTE frequency spectrum bands, 3G - WCDMA, 2G - GSM, FDD, TDD, FR1, FR2 mmWave

:bar_chart: Orange Romania – Spectrum Allocation (Based on Your Table)

Band 3GPP Duplex Mode Downlink (MHz) Width (MHz) Use
700 MHz n28 FDD 758–768 10 MHz Coverage / 5G low-band
800 MHz n20 FDD 806–816 10 MHz LTE fallback / coverage
900 MHz n8 FDD 950–960 10 MHz Legacy / LTE rural
1500 MHz n75 SDL 1432–1472 40 MHz Supplemental Downlink
1800 MHz n3 FDD 1835–1855 20 MHz LTE primary / anchor :heavy_check_mark:
2100 MHz n1 FDD 2140.1–2154.9 ~15 MHz LTE & NSA 5G (your current NR link) :heavy_check_mark:
2600 MHz n7 FDD 2630–2650 20 MHz High capacity LTE :heavy_check_mark:
3500 MHz n78 TDD 3550–3710 160 MHz Mid-band 5G (likely SA only) :fire:

Conclusion

  • Orange technically has enough spectrum for much better throughput.
  • But in my specific tower/sector, they appear to:
    • Cap LTE Band 3 to 10 MHz
    • Do not activate CA with Band 7
    • Use Band n1 for NSA, but also limited
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