Router as Wifi client with multiple antennas in RV

In my RV, my devices have terrible Wifi/mobile reception. I want to implement the following setup on a x86 Mini PC:

  • external antenna on the roof of my RV in order to connect to Wifi of the camping ground
  • internal antenna for my client devices (not quite sure if this is necessary, maybe if the antenna is outside, but still very close the reception is fine)
  • my own wifi network with own subnet etc.
  • 4G with external antenna as a fallback in case there is no Wifi to connect to (following this guide)

Before I commit to this idea I want to ask for a bit of feedback from you. I mainly have the following questions:

  • Assuming I want to have an external antenna as well as an internal antenna, do I need two wifi cards?
  • Same question but assuming I only use the external antenna
  • If both using one or two wifi cards is possible, are there any reasons to choose one over the other option?
  • Am I correct, that for my planned setup I don't need to follow the guides for dumb AP or Wifi extender (because these use DHCP from the main router), but instead follow Connect client wifi and basic wifi?
  • Anything else that's worth to consider/keep in mind?

External antennas never work as well as moving the whole radio outside, so I'd look at mounting something like a UAP-AC-Mesh or an EAP-225 Outdoor on the roof.

Campgrounds and 4G will not have enough speed to require an x86 CPU, lower power hardware will be fine for this use.

As far as the networking, you'd run a routed client. The upstream network is untrusted so consider it part of the Internet and keep it outside your firewall.


About what kind of performance reductions are we talking with external antennas? I need to run one anyway for my 4G card, so I thought I can combine it with Wi-Fi as well and skip the extra hardware. I would like to try that first and see if it’s technically feasible. If there are any quirks or I’m not satisfied with the performance, I can always buy the outdoor AP later and add it to the setup.

So, my question about one or two Wi-Fi cards is still open (also I’m interested in the answer for an unrelated project, where I might do something similar, even if I end up getting an outdoor AP).
Are there any (cheap) outdoor Wi-Fi/LTE/5G AP available, that do all the failover to mobile stuff internally? Then I could move all that logic to this device and use the mini pc as a basic Wi-Fi AP. The only products I found also use an external antenna (that’s where my idea came from, if it’s just an external antenna anyway, I can do that myself in Openwrt).

I know x86 is overkill, but an LTE router is in a similar price range, so I guess I can get a mini pc for the same money and have a lot more flexibility regarding upgrades or just raw performance for some other stuff (docker containers mainly).

It depends on the kind of cable. Generally the thicker cable the lower the loss (that's a simplification but works). Almost all wifi devices on the board side use U.FL connectors which limit the size of cable you can use. RG178 is about as thick as will work well with U.FL connectors and it has a loss close to 3db per meter at those frequencies. Which means you're dropping your signal in half every meter of cable.

Could you use, say, an inverted small plastic tote or other radio transparent cover to protect a normal device from the elements? Build yourself a small radome.

You might want to look at Banana Pi router boards. The router boards come with mPCIe and SIM slots you can add 5G cards to. They run OpenWRT quite well. You could build an outdoor device with one with not too much trouble.

Improvising may sound tempting for a 1 week in a livetime event, but you sound like a camper for life.

any indoor device which gets regularly exposed to UV rays, heat, outdoor humidity, night cycle (variation of humidity and temp) or salty sea weather will quickly corode or wear down metal connectors or electronic components. Probably some indoor plastic cases are not UV-resistant either.
A custom made plastic foil cover will have its limits, when edges need to be air-toght.

Plugging an extension cord between wifi antenna and wifi receiver likely will not result in good wifi signal results.
the access point part of the overall solution may need to cover clients used on the outside vicinity of the RV as well.

I would try to be flexible and get several combined devices: probably get 1 outdoor device + 1 indoor device + probably rather 1 outdoor-labeled LTE router, not just a regular indoor USB stick.
You dont need expensive stuff, the WAN pars probably will not give you more than 150mbits.

You could probably also check specialized forums for RVs and campers.