Improving router's coverage


Dec 18, 2013
I have an adimax br6208ac router with 3 antennas in a closet with cinderblock walls. I cannot relocate it because it connects to 5 Ethernet cables originating in the closet: one to the modem, 4 to wired Ethernet wall sockets plus the supply bloc. It seems to me that these antennas cannot be detached from the router. Is there a method to have a better coverage under these conditions, preferably with no additional repeater?
Thanks for your time
From what I can find online, this router uses a U.FL connector for the antenna, probably inside the unit. You can get a different U.FL antenna with higher gain, crack open the case, and screw it on in place of the standard antennas. Or you can get a directional antenna and screw it on, and point it at a direction which covers more of your house.

Or you can get a pigtail adapter which converts from U.FL to something more common like N or RP-SMA, and get an antenna that uses one of those connectors. Don't make the pigtail too long though, as the signal will degrade the longer (and thinner) the pigtail is, possibly canceling out any benefit from using a better antenna.

Or you can get a new router which uses screwn-on antennas. Probably RP-SMA, and get an appropriate antenna upgrade.

Be aware that the "omnidirectional" whip antennas are actually omnidirectional only in a plane. Their beam pattern is torus-shaped (like a donut), with the strongest signal strength out to the sides (perpendicular to the antenna), tapering down to almost zero signal strength up/down (parallel to the antenna).

So if you've got a multi-story house, you can improve coverage by tilting some of the antennas so the meat of their donut covers the different floors.

Also, higher gain antennas achieve higher gain by flattening the donut. They gain signal strength out to the sides (giving more range), but lose strength up/down in exchange (reduced range at an angle). So a higher gain antenna may not be ideal for a multi-story house (unless you tilt it).
You can buy another router and use it as a AP in another location in the house. You could if you really wanted to put one in every room that has ethernet ports. Many times people put in a wired only router in closets that are not in optimum places