MikroTik Chateau 5G internal/external antenna wiring for 4x4 MIMO

[Seán]

The MikroTik Chateau 5G has no software configurable antenna settings, unlike the LTE12 model.  In its factory supplied state, the Chateau 5G only uses the two external antenna connections for 5G on band n77/78, i.e. the 3.6GHz band.  

To use the Chateau 5G with an external 4G antenna, it requires disassembly to either rewire the existing external antenna sockets or the addition of two 20cm or longer U.fl to SMA pigtails.  

To remove the cover, first remove the rear screw, then carefully separate the front seam at the top/bottom using a Spudger or similar DIY repair tool, until the front cover lifts off.  I came across this YouTube video for opening the Chateau LTE12, which has the same outer casing as the 5G model. 

The following shows the original wiring in the Chateau 5G:

   

Original internal antenna wiring:
A0 - Top-right antenna
A1 - Lower-right antenna
A2 - Small 4.6-5.9 antenna bottom wire
A3 - Small 4.6-5.9 antenna top wire
A4 - External antenna port ANT4
A5 - External antenna port ANT1
A6 - Top-left antenna
A7 - Lower-left antenna

Notes:  Take care when detaching a U.fl connector, gently tilt up from the wire end about 30 degrees and it should come off.  Do not use any tool as this can damage the port or connector.  These connectors only handle a few insertion/removal cycles.  When attaching, align the connector with the port, then push down.  The connector only requires a little force to snap on.

To convert the existing external antenna ports for 4G, swap antenna ports A0 and A1 with ports A4 and A5 on the PCIe card.  In this configuration, the router will use the external ports for 2x2 MIMO on all bands below 2690MHz, including 5G on these lower bands, such as n3.  If there is sufficient indoor coverage, it will use the internal antennae for 4x4 MIMO including on band n78, where available.  

Before powering on, ensure every port A0-A7 has an antenna attached.  Do not leave any ports empty. Before refitting the cover, ensure no wire passes over the circuit board or screw hole where it could get pinched inside the cover.


RG502Q-EA Cellular Antenna Mapping:

   

• 1) LTE LB_TRX1 is activated when 5G NR FDD low bands are supported in NSA mode.
  
• 2) LTE UHB frequency range: 3400–3800 MHz.
  
• 3) LTE MHB_TRX1 is activated when 5G NR FDD middle/high bands are supported in NSA mode.
  

Source: RG50xQ Series Hardware Design

Frequency bands in table
LB = Low Bands - All bands up to 960MHz
LMHB = Low/Middle/High Bands - All bands up to 2690MHz
MHB = Middle/High Bands - All bands from 1452MHz or 1710MHz to 2690MHz
UHB = Ultra High Bands - Bands from 3400 to 3800MHz

4G LTE Antenna connections
TRX = Transmit/Receive - Antenna #1 for 2x2 or 4x4 MIMO
DRX = Diversity Receive - Antenna #2 for 2x2 or 4x4 MIMO
PRX MIMO = Primary Receive #2 - Antenna #3 for 4x4 MIMO
DRX MIMO = Diversity Receive #2 - Antenna #4 for 4x4 MIMO
TRX1 = LTE Antenna #1 paired with a 5G NSA connection over FDD LMH bands (see table notes 1 & 3 above)

5G NR Antenna connections
TRX(0) - Transmit/Receive - Antenna #1 for 2x2 or 4x4 MIMO
DRX(0) - Diversity Receive - Antenna #2 for 2x2 or 4x4 MIMO
TRX1 - Transmit/Receive #2 - Antenna #3 for 4x4 MIMO
DRX1 - Diversity Receive #2 - Antenna #4 for 4x4 MIMO


External antenna configuration suggestions

If you have an existing 2x2 MIMO external antenna and would like to upgrade to 4x4 MIMO, you can purchase another of the same or similar 2x2 MIMO external antenna.  Mount the second MIMO antenna at a 45 degree offset to the primary antenna.  For example, if the primary MIMO antenna is polarised vertical/horizontal, mount the second MIMO antenna at +/-45 degrees.  For two Poynting XPOL-2's, the bracket has a 45 degree mounting position to mount the second XPOL-2 with a 45 degree offset.  Further info in this post.

For 5G band n78, the antenna must cover frequencies to 3.8GHz.  If the existing antenna does not cover band n78, another option would be to purchase a second MIMO antenna that covers up to 3.8GHz and go with configuration #1 or #3 below, using the band n78 capable antenna for leads #3 and #4. 


Configuration 1 - For best 4G or combined 4G/5G in all coverage areas

• 4G 2x2 or 4x4 MIMO on all 4G bands 1/3/20/28 and future bands 7/38/40
  
• 5G 2x2 or 4x4 MIMO on all refarmed bands such as n1 or n3
  
• 5G 2x2 MIMO on band n78 (No external upload MIMO)
  

A0 - Lead #1 of 2x2 or 4x4 MIMO antenna
A1 - Lead #2 of 2x2 or 4x4 MIMO antenna
A4 - Lead #3 of 4x4 MIMO antenna
A6 - Lead #4 of 4x4 MIMO antenna

Note: Eir and Three will use band 20 or 28 as the 4G carrier with a 5G NSA connection on band n3.  These low 4G bands use ports A0/A1, so this 4x4 configuration should work even where indoor 4G coverage is poor.


Configuration 2 - For best 5G band n78 performance, requires adequate indoor 4G coverage

• 4G uses internal antennas
  
• 5G 4x4 MIMO on band n78
  

A4 - Lead #1 of 4x4 MIMO antenna
A5 - Lead #2 of 4x4 MIMO antenna
A6 - Lead #3 of 4x4 MIMO antenna
A7 - Lead #4 of 4x4 MIMO antenna


Configuration 3 - For best aggregated 4G+5G upload performance in all coverage areas

• 4G 2x2 MIMO on all 4G bands 1/3/20/28 and future bands 7/38/40
  
• 5G 2x2 MIMO on band n78 with upload MIMO (faster upload than configuration #1)
  
• 5G 2x2 MIMO on all refarmed bands such as n1 or n3
  

A0 - Lead #1 of 2x2 MIMO 4G antenna
A1 - Lead #2 of 2x2 MIMO 4G antenna
A4 - Lead #1 of 2x2 MIMO 5G n78 capable antenna
A5 - Lead #2 of 2x2 MIMO 5G n78 capable antenna

[qatar2022]

thank you
but you didn't mention if i (( swap antenna ports A0 with witch port exactly A4 or A5 and A1 with witch ports A4 or A5 on the PCIe card ))
or it doesn't matter
best regards

[Seán]

You can swap them either way around. The only difference would be which rear antenna port becomes the primary port that transmits. This does not matter with MIMO antennas as the leads can also be attached either way around. The only time it would become an issue is when attaching just a single antenna for 3G only use, which must route to port A0 on the modem.

[Pepper911]

You can swap them either way around.  The only difference would be which rear antenna port becomes the primary port that transmits.  This does not matter with MIMO antennas as the leads can also be attached either way around.  The only time it would become an issue is when attaching just a single antenna for 3G only use, which must route to port A0 on the modem.

Hi, I would need some help by you...
when I looked at the router webfig menu I saw that on modem properties I could choose between the modem antennas from "both","main","diversity".

In my current situation it would be very helpful to connect to two different bts that are 150 degrees one from another, with different log antennas, and then have the ability to switch between one bts and the other.

I tried to point 2 log antennas (connected to port 0 and 4) to one bts, and point other 2 log antennas to the other bts (connected to port 1 and 5). The two bts are separated by an orientation of 150 degrees so the antennas should not connect to the bts to which I pointed the second 2 antennas.

no matter what I choose from modem properties ("both","main","diversity") I can never connect to the bts of port 1&5. I can always detect only the bts of antennas 0&4...

I don't understand what I'm doing wrong...

LTE bands of my zone are 1,3,7 and 20, and I don't have 5G coverage.

Could you please help me understand what's wrong?

Many thanks in advance!

[Seán]

Unfortunately, the Chateau 5G model does not have any actual hardware antenna switching capability, unlike the Chateau LTE12.  This circuitry is left out on the PCB above the modem and only present on the Chateau LTE12 model.  MikroTik has removed this setting in recent Winbox versions for the Chateau 5G. 

Modem ports 0 and 1 handle those LTE bands, so only use these two ports for a pair of LOG antennas.  Antenna ports 4 and 6 are only for 4x4 MIMO with a second pair of antennas pointing the same direction, e.g. one pair Horizontal/Vertical and another pair -45/+45 degrees all facing the same mast. 

The best option here would be to get SMA test connectors to attach to the end of the antenna leads (such as these).  This would let you quickly swap over the antenna leads between the antennas facing different directions.  Coaxial A/B switches would also work, however these are expensive and difficult to get hold of.

Another option would be to get the MikroTik LTE12 (or LTE18 if available) model and install two U.fl to SMA leads between the internal antenna ports and the two spare antenna ports on the rear.  This would let you switch between the two pairs of antennas in Winbox or the web interface with that Main/Both setting.

[Henrik]

The MikroTik Chateau 5G has no software configurable antenna settings, unlike the LTE12 model.  In its factory supplied state, the Chateau 5G only uses the two external antenna connections for 5G on band n77/78, i.e. the 3.6GHz band.  

To use the Chateau 5G with an external 4G antenna, it requires disassembly to either rewire the existing external antenna sockets or the addition of two 20cm or longer U.fl to SMA pigtails.  
[...]

Hi Sean,

If you want to go ahead with three Poynting XPOL-2's for best combined 4G/5G NSA coverage on band N78 alternatively N28, how would you mount the antennas 60 cm appart what angels on the different antennas and which lead goes to what antenna?

Option 1:
A0 - Lead #1 of 2x2 or 4x4 MIMO antenna
A1 - Lead #2 of 2x2 or 4x4 MIMO antenna
A4 - Lead #1 of 4x4 MIMO antenna
A5 - Lead #2 of 4x4 MIMO antenna
A6 - Lead #3 of 4x4 MIMO antenna
A7 - Lead #4 of 4x4 MIMO antenna

Option 2:
A0 - Lead #1 of 2x2 or 4x4 MIMO antenna
A1 - Lead #2 of 2x2 or 4x4 MIMO antenna
A4 - Lead #1 of 4x4 MIMO antenna
A6 - Lead #2 of 4x4 MIMO antenna
[b][b]A5 - [/b][/b]Lead #2 of 4x4 MIMO antenna
A7 - Lead #4 of 4x4 MIMO antenna

Please explain any differences/advantages or disadvantages of the options above or other option?

Many thanks.

[Seán]

I suggest mounting two antennas in a square position (i.e. Horizontal / Vertical) and one antenna in a diamond position (i.e. +/- 45 degrees).

Connect them as follows:
A0 - Lead #1 of antenna #1 (Square)
A1 - Lead #2 of antenna #1 (Square)
A4 - Lead #1 of Antenna #2 (Diamond)
A5 - Lead #1 of Antenna #3 (Square)
A6 - Lead #2 of Antenna #2 (Diamond)
A7 - Lead #2 of Antenna #3 (Square)

When it connects on 5G band n78, it will use A0+A1 for 4G MIMO #1 (Antenna 1). If the 4G connection is 4x4 MIMO capable, it will use A4+A6 for 4G MIMO #2 (Antenna 2). For 5G, it will use A4+A6 for MIMO #1 (Antenna 2) and A5+A7 for MIMO #2 (Antenna 3)

When it connects on 5G band n28, it will use A0+A1 for 4G MIMO #1 (Antenna 1). If the 4G connection is 4x4 MIMO capable, it will use A4+A6 for 4G MIMO #2 (Antenna 2). For 5G, it will use A0+A1 (Antenna 1). Antenna #3 is unused with 5G band n28.

[Seán]

MikroTik has announced two new Chateau models, the Chateau LTE18 ax and the Chateau 5G ax with the following new features / improvements:

• Wi-Fi 6 (802.11ax)
  
• USB3 port (faster tethering from a USB3 capable 5G phone)
  
• 2.5G Ethernet port (and 4 Gigabit ports)
  
• Cat 18 modem on the Chateau LTE18 ax model.  
  
• 2 external Wi-Fi antennas
  
• 1GB RAM (vs 256MB)
  
• 128MB storage (vs 16MB)
  
• 64-bit architecture (vs 32-bit)
  
• 1.8GHz 4-core CPU (vs 716MHz)
  

Note: The two black antennas on the LTE18 ax and the two outer antennas on the Chateau 5G are Wi-Fi antennas.  This means it is still necessary to install two additional U.fl to SMA pigtails internally to provide 4x4 MIMO for external antennas.

Product information links:

Chateau LTE18 ax:  https://mikrotik.com/product/chateaulte18_ax
Chateau 5G: https://mikrotik.com/product/chateau_5g_ax

[123com]

MikroTik has announced two new Chateau models, the Chateau LTE18 ax and the Chateau 5G ax with the following new features / improvements:

• Wi-Fi 6 (802.11ax)
  
• USB3 port (faster tethering from a USB3 capable 5G phone)
  
• 2.5G Ethernet port (and 4 Gigabit ports)
  
• Cat 18 modem on the Chateau LTE18 ax model.  
  
• 2 external Wi-Fi antennas
  
• 1GB RAM (vs 256MB)
  
• 128MB storage (vs 16MB)
  
• 64-bit architecture (vs 32-bit)
  
• 1.8GHz 4-core CPU (vs 716MHz)
  

Note: The two black antennas on the LTE18 ax and the two outer antennas on the Chateau 5G are Wi-Fi antennas.  This means it is still necessary to install two additional U.fl to SMA pigtails internally to provide 4x4 MIMO for external antennas.

Product information links:

Chateau LTE18 ax:  https://mikrotik.com/product/chateaulte18_ax
Chateau 5G: https://mikrotik.com/product/chateau_5g_ax

Here pictures of the chateau 5g ax incl antenna mods

[Seán]

Thank you for sharing images of the Chateau 5G AX internals, looks like a complete PCB redesign compared to the original Chateau 5G. Clearly requires further disassembly such as removing the PCB to install the pigtails. At least the m.2 modem remains removable as a future upgrade option.

With the external antenna connections, you will unlikely need to connect anything leading to modem ports A2 or A3 as these are for 5G band n79 (4.4-5GHz), which is currently only used in a few Asian countries such as China, Hong Kong and Japan.