Hi,
From firmware 8.3 it is posible to enable the “2x antenna mode”, which allows us to use 5G with “some performance loss” according to the Peplink 8.3 webinar
Our customers ask us many times how much is some performance loss. For them, running the extra cables is a potential headache (we work on yachts) so it is important to quantify how much less performance they’ll get to make the decission.
I saw on one of the forum topics the user “Giedrus” posted the following:
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
My question is, how much slower is 5G in 2x antenna mode? At least in terms of theoretical maximum speed.
Also I’m concerned about the 5G band support in 2x antenna mode. I’ve seen in two Peplink retail websites the following statement:
“(When in 2x antenna mode) the cellular modem will not be able to use bands B42/43/46/48 of LTE and n48/n70/n77/n78/n79 of NR5G.”
Could you please confirm this? Band 78 is quite important in Spain, and not being able to connect to it with a 2x2 antenna is a big concern
Hi Santiago,
Welcome to the forum.
First off all the 2x2 antenna mode (the mode you enable in the GUI) is only available for 5GH models. You can see this when you check the SKU on the silver lable on your Peplink device next to the serial number.
When connection 2 antennas instead of 4 antennas it’s like going from a highway of 4 lanes to a highway of 2 lanes, simply explained. This will result in lower speeds when more bandwidth is required. So in your situation the yacht will have lower speeds when high bandwidth is required. @Captain_Nik can help with this too. Maybe a Dome solution would be better in that case so you don’t need to worry about the antennas connected.
In the post by Giedrius there is indeed mention of N78 not working, however this might be in some scenarios the case. We have tested on Private 5G with N78 and it does connect. However it is super fragile if there is a drop or frequency shadow on that Antenna element you can loos the connection to the cell tower easily. This is due to the way the bands are shared across the connectors. In your case this could be ship turns around and the antenna element is now blocked by the ships mast.
I have this overview, only looking at sub 6Ghz frequencies:
ANT0 / Connector A: n77/n78/n79 TX1/DRX.
Explains to:
Upload (TX1) as Diversity connector for n77/n78/n79 bands.
Download (DRX) as Diversity connector for n77/n78/n79 bands.
ANT1 / Connector B: n77/n78/n79 PRX MIMO.
Explains to:
Primary (PRX) MIMO download connector on the n77/n78/n79 bands.
ANT2 / Connector C: n77/n78/n79 TX0/PRX.
Explains to:
Upload (TX0) as Primary connector for n77/n78/n79 bands.
Download (PRX) as Primary connector for n77/n78/n79 bands.
ANT3 / Connector D: n77/n78/n79 DRX MIMO.
Explains to:
Download (DRX) MIMO Diversity connector on the n77/n78/n79 bands.
Hope this helps. 
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Hi AstroJoe,
Thank you very much for your extensive answer. Much appreciated.
1 Like
No problem happy to help!
Let me know if there is anything else