Question LTE indoor antennas, worth the try?

[kamild_]

I use LTE for my home internet, and as far as performance goes, it's already pretty good. But after checking my signal strength stats on my router (Mikrotik Chateau LTE12) and looking them up, I found out there's possibly plenty of room for improvement. My signal strength metrics on average:

• RSRQ: -7 dB
• RSRP: -112 dBm
• RSSI: -84 dBm
• SINR: 12 dB

The only station I'm using is approximately 400 meters away, but between it and my router (which sits in the corner of my room) there are 2 concrete walls and a handful of trees. Is there any hope for improving signal strength with an indoor antenna located somewhere close to the router, or is this not worth even attempting and I shouldn't even approach this topic without being ready to mount an antenna outdoors, possibly on a roof/mast?

 

[bill001g]

So the first question is can you even attach a antenna to the router. Most external antenna connections are for wifi. Using antenna on cellular devices is illegal and rules require them to make it hard to add antenna.
The exception to this at least in the USA is that you can do it with the permission of the license holder ..ie the cell company. Problem is even if the cell company gives you permission they will never give you the paperwork that makes it legal.

Not that they enforce these laws much, technically putting larger antenna on your wifi is also illegal.

So if there is a antenna connector for lte....likely there will be 2 or more you might try a antenna. It is going to be the same antenna that you would use outside. This is a example of a really fancy one that has 4 antenna, many lte systems use more than 1 overlapping signal to get more speed.
You might get by with just a single antenna like this. This is more to show all the cables etc that you need. What you want to search for is "log periodic antenna".

https://www.amazon.com/Periodic-External-Antenna-Hotspots-Routers/dp/B09VVWMS2F/

It likely will work better if you could put it outside but maybe try just a single antenna inside. They are not real exepensive what tends to increase the price a lot is the long cables that run outside. You need quality cables that do not lose all the signal that the antenna adds.

 

[kamild_]

Yeah, my router has SMA connectors to connect an LTE antenna into. I'm not aware of legal issues regarding an installation of such an antenna in my country (Poland).

This router (from my understanding) already has an internal 4x4 MIMO antenna, so if I ever want to at least match the current speeds, I would need the same kind of an external antenna, right? The $400 price tag on the one you linked worries me a little...

 

[bill001g]

That is because it has all the parts you could need. You likely can save a bit by buying it separately. Hard to say I have not looked at this in detail for a number of years.

You can get single antenna for about $30. The tricky part is they come with "N" connectors in most cases. This is the standard type of conenctor used with antenna. Because of the legal restrictions you now must find a way to adapt this to what ever connector your router has.

Be very careful if it is SMA then it could be for LTE. RP-SMA is what they use for wifi and look similar but are actually reversed. This is the trick they did to make it hard to install normal antenna, but of course you can just buy adapters even for wifi.