MR1100 primary 4G band problem with distant 4G+ site

[SeánB]

I am in a rural part of Ireland where I pick up a 4G+ site quite far away with the help of an outdoor MIMO antenna.  The cell operates on bands 20, 3 and 1 and my previous LTE Cat 6 router worked fine operating either with 20+1 or 20+3 carrier aggregation, using band 20 as the primary upload band.

When I try attaching the antennas to my Netgear M1, it initially starts up fine showing 'B20' as the band in the status screen and '4G+' on its display.  During this time, I get over double the speed of my previous router as it seems to use all three bands for carrier aggregation. 

Within a minute, the M1 tries switching to either band 1 or 3, causing the connection to drop as I seem to be outside the cell's propagation limit for connecting to band 1 or 3 as the primary/upload band. When it does this, it gets stuck trying to use that band as shown in the screenshot. This seems to be a bug as my previous router never got stuck like this. 

While I can lock the router to band 20 using an "AT!BAND" terminal command, it loses the carrier aggregation, giving me a very slow connection, defeating the whole point of purchasing this router.  When I switch it back to "LTE All", I get full speed again for about a minute, after which the M1 drops the connection when it gets stuck trying to switch over to band 1 or 3.

Is there any way I can force the M1 to keep using band 20 as the primary band, without preventing it using the other bands for carrier aggregation? ... or better still, fix this bug.

The router has firmware version NTG9X50C_12.06.11.00.

[Blanca_O]

Hi @SeánB

Welcome to NETGEAR Community!

May we please know the device SKU (MR1100-xxxxx)? 

The following KB links will show list of supported bands: 

What cellular bands are supported by MR1100 Nighthawk M1 Mobile Router?

What cellular bands are supported by the external antenna connectors on MR1100 Nighthawk M1 Mobile R...

Regards,
Blanca
Community Team
 

[SeánB]

Thanks for replying.  The device SKU printed at the bottom is MR1100-100EUS and the H/W is 1.0.

Since posting above, it received a firmware update, current version is NTG9X50C_12.06.12.00.  The issue remains in this verson.

My provider operates on bands 1, 3 and 20, which that cellular bands article shows this covers.  Due to my distance from the cell tower, I can use band 20 as the primary band (transmit & receive) and bands 1 and 3 for carrier aggregation (receive only). 

From further testing, the M1 seems to switch to band 1 or 3 when the RSRP of either band is around -108dBm or less negative.  As a crude workaround, I attached extension leads to the antenna leads to deliberately attenuate the signal.  It now stays on band 20 longer while still being able to use the (now very weak) signal on bands 1 and 3 for carrier aggregation. 

Even with the signal weakened, it still occasionally jumps to band 3 as the RSRP fluctuates up/down depending on the weather, in which case I have go into the web interface to toggle the mode between band 20 and 'LTE ALL' to restore Internet access.  It appears that the router is not detecting that the cell is not allowing it transmit to it on bands 1 or 3 and in turn getting stuck trying. 

[W1lliam]

Possible improvement could be getting customized LTE antenna designed for B20 (below 1700MHz is fine), which can improve B20 signal quality then you probably can stay on B20 as main band. Plug into TS-9 ports should work.

[JohnPeng]

I agreed with William. You may have to get a better external antenna or adjust your antenna location to see whether the device can pick up better signal on B20. It is just tracky location for the device to work on B1, B3 and B20.

[SeánB]

I have a pair of 90cm (3ft) cross-polarised LOG periodic antennae that covers 700-900MHz, so gave this a trial run with a tripod.

With the current 1.05m (3.5ft) large wideband LOG periodic antennae that covers 700-2700MHz, I get about -100dB on band 20, band 3 and 1.  I have clear line of sight with the distant mast across a bay as usually vegetation attenuates the higher frequency bands.

With the 700-900MHz antennae on a tripod, I get about -90dB on band 20, -112dB on band 3 and -115dB on band 1.  The router didn't change from band 20 during the 30 minutes I had this temporary set up. 

Carrier aggregation also works, although with 60-70% the speed I got with the wideband antennae due to bands 1 & 3 being attenuated by 12-15dB. 

I presume being told to change my antennae means that this bug is not fixable, so will try swapping the antenna when I get a chance. 

[W1lliam]

Alternatively, you can have one 700-900MHz antenna plugged into one of TS-9 port and having wideband antenna used for another port, try and swapping them for comparison.

[mdcartstudio]

Hi everyone, the suppoted bands for the Netgear Nighthawk M1 Model MR1100-100NAS (North America)* are 1, 2, 3, 4, 5, 7, 12, 14, 20, 29, 30, 46 and 66 (14) Firstnet and you can select and lock the best band 😉 I recommend to unlock the device and if you live in a rural place get this signal booster!..

https://www.weboost.com/boosters/att-signal-booster

 For unlock follow this video..

https://youtu.be/WOvIF1A2MV4

And for band locking 😉 this one!

https://youtu.be/GtqLH6yzqdM

I hope this help you guys!

Warm Regards, Leo R.

[SeánB]

After a few days waiting for the weather to improve, I finally got the band 20 antennae installed. It took a few hours due to routing the cabling through the loft and getting the antennae aligned up.

Unfortunately, it was not successful.  Within 15 minutes of taking down the ladder, my Internet connection dropped.  I opened up the Nighthawk M1 status page and sure enough, it was stuck again on band 3!

I rebooted the M1 and it booted up showing band 20 with a -95dBm signal and 4G+.  A few minutes later, it switched again to band 3 showing a -108dBm signal. This rules out the theory that a much stronger band 20 signal will hold it on that band.

As Netgear is either unable or unwilling to fix this issue, I debating now on selling it as I'm back on my old router again that doesn't have this issue. 

[W1lliam]

There is another two internal antenna has impact on band(s) you like to stay, this can't be done without any rework on the device.