5G repeaters, do they exist?

I know it's a very big long shot, but is anyone aware of any sort of device that can boost / repeat 5G signals? I get great 5G coverage outside but get barely any inside, regardless of the network. Thought it'd be pretty awesome to stick a 5G antenna outside, hook it up to some sort of repeater device and create a little mini 5G network inside. I would opt for a 5G router and connect it to an outdoor aerial, but that would mean having to have two separate SIM cards rather than just having the one SIM card and tethering other devices to my phone.

Does anyone or any device need the internet when you go out with your phone? For example simply recording a live internet TV program from a station with no catch-up?

I had to get a router to support my cloud-linked security cameras when I got those.

In reply to a post by RebootTheRouter:

I know it's a very big long shot, but is anyone aware of any sort of device that can boost / repeat 5G signals? I get great 5G coverage outside but get barely any inside, regardless of the network. Thought it'd be pretty awesome to stick a 5G antenna outside, hook it up to some sort of repeater device and create a little mini 5G network inside. I would opt for a 5G router and connect it to an outdoor aerial, but that would mean having to have two separate SIM cards rather than just having the one SIM card and tethering other devices to my phone.

Have a look at https://signalboosters.co.uk/collections/products

An alternative solution would be an external 4/5G router (such as a Zyxel MC7010) then just take the Ethernet indoors and reticulate as needed. Much cheaper than the boosters. You can always mount the router in a parabolic (like a sky dish) to optimise it’s signal reception.

In reply to a post by RebootTheRouter:

I know it's a very big long shot, but is anyone aware of any sort of device that can boost / repeat 5G signals? I get great 5G coverage outside but get barely any inside, regardless of the network.

Common for most as majority of 5G today is in the 3.5 GHz band which gets through glass but not through brick. Some homes have insulation in the walls that stops mobile signals. Some networks are starting to use other frequencies for 5G where 3G and 4G used to be.

Outside of enterprise settings or where there is a requirement to provide indoor coverage to visiting members of the public (shopping centres, stadiums etc.) the attitude that networks have now to this problem is to use Wi-Fi calling.

The cost of any Cel-Fi type device is going to exceed the costs of another SIM with external router, and I think they all top out at 4G currently anyway.