Is sim slot A linked to antenna ports “A” & “B” ?


Is sim slot B linked to antenna ports “C” & “D” ?

Nope. ABCD are all used by the single 5G modem (and the modem uses either Sim A or Sim B at any one time). 5G uses MIMO for multiple carrier aggregation which requires data being sent and received on multiple frequencies at the same time. That in turn requires multiple antennas.

You can however just connect two antennas - but available bandwidth in some situations will be greatly reduced.

See: Peplink | Pepwave - Forum

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Thanks !

If we connect a Maritime 20G (2 cell coax cables) to A&B


leave the stock 6" plastic antennas on C&D

What should we expect performance relative to all 6" stock antennas?

In that post, it would seem to read that on the -5GD SKUs, antenna terminals A and C do Tx and Rx, while terminals B and D only do Rx. Do you know if that’s correct or is there another reasoning that A and C would be used in conjuction when needing to use 2 antennas. If you’re not certain, Maybe @Giedrius could confirm?

This question is always too complicated to answer as there are too many variables.

When it comes to cellular its always an additive thing, higher quality mobile network operators, better antennas, better cables, better antenna height and separation etc all typically improve performance - until they don’t (which happens sometimes).

However, typically you should expect better performance than with standard paddle antennas.


Yes, the reason you use the A & C terminals for that chipset is because those are the TX terminals… so you maximize your transmit MIMO capabilities. Your receive is only going to be 2x2 anyway… If you used another combination then you would have 2x2 recive and 1x transmit. The other 2 paddle antennas might receive some signal… they might not, the chipsets will decide based on the signal received.

All of these MIMO, QAM and CA choices are beyond your control. The Cellular provider and the modems negotiate them to the best of the ability of the current environment, and change them second by second. As Martin states, the performance is what you get… what the environment can handle and what the Carrier is willing to give you, and you just use the best modem and antenna set you can. The combination of technolofgies (MIMO, QAM, CA) all work together to maximize the complete connection. It will never be MAX performance for the technology as that is from a lab where 100% of the resources are dedicated to the test.

I linked to a technical paperl on MIMO here



That is the case yes. If you look at the specs for the Thales MV31-W which is seen a lot in 5G products, two antennas are RX/TX and two are RX only.


Hi Martin, the link this post isn’t working for me and I’m looking for clarification on which ports are Tx/Rx vs just Rx for a 5GH model of the BR1 5G Pro.

I don’t see this referenced anywhere in the datasheets, install guides or user manuals.


@Giedrius knows the answer for sure, but there is also a later post about this and software selectable’ 2 antenna mode’ somewhere on here… Search is not helping me find it yet.

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For BR1 5G Pro with -5GH option you should use antenna terminals A and D. Also, to make it work properly, you should enable 2x Antenna mode via UI. The 2x antenna mode support was added in 8.3.0 FW release. So please make sure you have the FW updated as well.

Below is a screenshot from the 8.3.0 release notes:

The main drawbacks once 2x mode is enabled are:

  • LTE category downgrade from 20 to 16.
  • 4x4 MIMO for some bands are changed to 2x2 MIMO support.
  • N41 band support is turned off.

Thank you, appreciate the information.

Thank you, appreciate the information.

Where in the UI is the menu option for 2 x antenna mode?


Post #45

Hi Liam,

below is how it looks on my BR1 Pro 5G (-5GH).

Click on cellular interface as shown below:

Then scroll down to Cellular Settings section. Click on the question mark at the top right corner and then click on Here link as shown below:

This will open a new configuration option allowing to enable 2x antenna mode. See screenshot below:


Sorry to bring up this ancient thread. But does this info also apply to the max br2 pro routers? I can’t find the 2 antenna setting in the 8.4.0 firmware. And if i wanted to connect only 2 antenna’s per modem on the max BR2. Which connectors do I use?

Hi Maarten,

2x antenna mode for -5GH SKU is available in 8.4.0 as well. The router model is not really important as it depends on a modem. So any product which has -5GH in its SKU (e.g. MAX-BR2-PRO**-5GH**-T-PRM) will support 2x antenna mode (BR1 Pro, BR2 Pro, MBX, etc). Once 2x antenna mode is enabled, please connect your antenna to A and D connectors.

In case your router has -5GN, then you should connect all 4x antennas as 2x antenna mode is not supported. For -5GD SKU doesn’t have special option to enable 2x antenna mode, but in case you need it, please connect antenna to A and C connectors.


To confirm 5GN doesn’t support two antenna mode , via the gui or just connecting two cables correct?
If so this needs to be added to all 5g product datasheets so customers/partners know.
Same with 5GD if it’s not really supported.
Are 5GH models still being made?

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Hi Jonathan,

5GN doesn’t support two antenna mode. You always need to connect 4 antennas.
As I remember, on Peplink WEB pages and also in the FW release notes it was mentioned that 2x antenna mode is available on -5GH models only.

In the long term -5GD and -5GH will be replaced by -5GN as this is based on a 2nd generation 5G modem chipset. For -5GH availability it would be best to contact your local VAD so that they could check which model you need and it if it is still available in the stock.

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