Connect external antenna

Is it possible to setup the following idea?

Currently I have this setup.
ISP Internet router ---> cable to linksys 1200AC router which has openwrt on it ---> Home WiFi hotspot.

But would this be possible?
ISP Internet router ----> External WiFi antenna connected via USB in AC1200 where the internet is coming in ----> Home WiFi hotspot

So basically receive the internet via external antenna isntead of UTP cable directly connected to the ISP router.


I assume you mean a USB Wifi Adapter, or?
You actually even could just use one of the radios of the AC1200 to connect to the ISP internet router (assuming that router supports wifi).

In general, USB wireless cards are ~errm, how to phrase this PG-13~ 'not good'…

  • tiny cases, prone to overheating when used over longer periods of time.
  • antennas too close too each other for (Mu-)MIMO to work properly
  • antennas too small (and often just PCB traces anyways) for good range
  • AP mode would open another can of worms (driver and firmware deficiencies)

Yes, you pay the repeater effect by reusing your AP's internal wireless card for an uplink connection and as your local AP, but that's usually a small price to pay compared to the 'fun' of USB wireless cards.

Exceptions may apply, but I haven't found any among the ~30 different USB wireless cards I worked with over the last 18 years.


A wired connection will have higher performance.

The best way to do this, if you have to, is to use one router as the client of the ISP box, wired to another router some distance away on a separate radio channel, as the AP for users.

The second best way is to run AP and STA on the same internal radio, so those operations will be synchronized to each other. Two radios on the same band in close proximity (like a USB stuck in the back of the router between the antennas) tend to jam each other.

The problem is that the internet router is like 250 meters away. The AC1200 antenna can't reach it so have to use an external directional antenna to receive the signal from the ISP Router. But how do I configure that external directional antenna if I connect it via USB?

Identify the chipset in the USB adapter and install the drivers for it. If the chipset is Linux compatible (and it has to be for it work with OpenWrt), plugging the adapter into a laptop or desktop running a full Linux distro will show which driver it uses.

Once the adapter is recognized and attached by a driver, it should appear as an additional radio on the network--wireless page.

Very few standard wifi products can bridge that gap, even in ideal conditions (open air, line-of-sight, and little-to-no RF interference). If you have any obstructions (walls, windows, trees, etc.) or non-ideal RF conditions, it will be even harder. A typical USB dongle is almost certainly not going to be able to do what you want. You would need one with a very high gain directional external antenna and a high performance radio section.

As said earlier, a wired link is always preferred when possible. Is there a reason that you are trying to eliminate that connection? And is that connection really running 250m? That would be 2.5x the maximum spec'd length of standard ethernet (there are some cables that advertise this capability, and ethernet doesn't magically break at 101m or anything like that, but it is out of spec and isn't considered reliable >100m. Fiber can go the distance without issue.

If you really need a radio link between the main router and your downstream network, you probably need devices that are designed specifically for that purpose -- known as point-to-point radios -- they are not traditional wifi, but are designed to bridge larger gaps transparently like a 'wireless wire.'


Exactly, cable with hubs in between is just a pain all the time so have to go for the wireless solution on this one.
I have a very strong directional yagi that can bridge the distance without any obstacle, i also have a dish that goes like 7km if without obstruction. So the distance is not the issue. Will connect tomorrow again and see if it appears as a radio. It has a rtl something in it, can check that tomorrow as well with an lsusb on kali or so.