All DrayTek routers and access points are supplied with 3dB omni-directional antennas as standard; These use an RP-SMA connector and can be replaced with higher gain antennas to alter the signal or to beam the signal in a specific direction. A common reason for replacing an antenna may be to use a directional antenna for point to point WLAN bridge with a couple of AP's or to direct the signal in a way that's more appropriate for the environmental topology. For further information on Antenna Theory please see here
When replacing antennas, it is recommended to replace the antennas that are used for both Transmit and Receive rather than a Receive Only antenna to make the most difference to signal range and achievable throughput and to maintain the diversity that having multiple antenna offers.
Please check the Antenna Usage table for the purpose of each antenna, this image shows how the numbering scheme works for each device:
1 - The DrayTek Vigor 2860Ln router has four antennas, the outer two antennas are the 2.4GHz wireless LAN antennas in the locations displayed in the image above. The two inner antennas are SMA fitting for the LTE radio. This is covered in more detail here.
Using a single antenna
In some scenarios i.e. when making a point to point wireless link using an antenna such as the DrayTek ANT-2510 10dB directional antenna, it is best to replace the two transmit/receive antennas to retain the MIMO functionality but if replacing just one antenna, using that antenna along with the standard antennas will cause problems with the antenna diversity functionality and could give a less usable wireless connection than with the standard antennas.
To resolve that, the routers can be set to use a single antenna which may give a reduction in speed potentially but can improve range over allowing it to use all three antennas.
Access the router’s telnet interface and enter “wl ht antenna 3” followed by “wl restart” and the router will then use only antenna number 1 (refer to the earlier antenna image).
It can be put back to its original state by entering “wl ht antenna 0” followed by “wl restart”.
On the Vigor Access Points (AP-710, AP-800, AP-810, AP-900), this can be set from the [Wireless LAN] – [General Setup] page by changing the Antenna setting to 1T1R.
- First Published: 25/09/2014
- Last Updated: 10/01/2017