MiFi maximum throughput, no 4G?

Technical Support for Routers
1

Hi,

 

I am using a gl-mifi with a Quectel EC25-E in Singapore. My service provider uses LTE B3 and B7, and on my phone I am able to get upwards of 65 Mbps on the downlink (I don’t remember uplink but its similar). However, when I use my Sim card in the gl-mifi, I am consistently getting 21 Mbps on both the uplink and the downlink, which makes me suspect that the modem is only using 3G. I have the gl-mifi hooked up via Ethernet cable from the LAN port to my PC. I have tried using the AT command recommended in Overview - GL.iNet Docs to limit the modem to LTE, but I didn’t see any change in the speed. Also, if I run uqmi -d /dev/cdc-wdm0 --get-signal-info, the OS reports

{
“type”: “lte”,
“rssi”: -61,
“rsrq”: -7,
“rsrp”: -88,
“snr”: 192
}

SNR seems wrong, but otherwise it looks like LTE. So a couple of questions.

  1. How can I debug this further to maybe check whether LTE is really being used.

  2. What is the maximum uplink and downlink speeds I can expect? Is the speed somehow limited by the modem-ar9331 interface, or perhaps somewhere else?

 

thanks,

Aaron

 

2

Are you using QMI mode? Maybe it is because of the signal?

21Mbps is definitely 4G

3

Thanks for the quick reply.

According to what I’ve read hspa+ (3.5G) reaches 42Mbps so I’m confused. But how would I check if I’m in qmi mode? Also how do I know what band I’m using? I’ve been going through all the qmi commands but I’m a bit lost.

 

Thanks

Aaron

Edit:

Okay based on reading the datasheet, you are right and it must be 4G since the advertised hspa+ speed is nowhere near 21Mbps.

So what is the bottleneck (the modem itself, the USB interface…any hints)? I realise that the EC25 is an m2m/iot optimized device so perhaps throughput isn’t the main consideration?

BTW I am using the default firmware.

Thanks

 

4

I would not be surprised if the MiFi maxed out at around 21Mbps. Back before I accidentally nuked my EC-25A I was seeing almost that exact number when signal strength was at it’s best (otherwise it dropped slower as the the signal went down). Keep in mind the MiFi is powered by a 400 Mhz MIPS CPU, so if you’re using it to do NAT between your cell provider and your local device I would expect ~20Mbps would be a reasonable limit of what the processor could handle. Maybe Alzhao has some further details on that though, just my observations.

5

Actually I have an update on this. I flashed the openwrt CC domino firmware and the throughout improved a little (25Mbps DL, 29Mbps UL), but I was testing it at a location with better signal strength too so I can’t confirm why the throughout improved.

I’m also wondering if it’s a CPU limit, but I also have the gl-300m WiFi router and it can get around 90Mbps between the WiFi and the Ethernet interfaces. It’s not the same thing as LTE, but the difference is pretty huge considering the chipset upgrade is only small.

 

Regards,

Aaron

6

I think the greatest effect with speed limited for EC-25A is the antenna , becase the test in my environment, the mifi’ download is about 7Mbps and upload is about 6 Mbps. but when I unwrap the packing and exchange the antenna outside. the download will get to 17Mbps and upload will get to about 12Mbps.