Sitecom WLX-5000 Manual page 20

Root AP SSID
Site Survey
In 'Universal Repeater' mode, this device can act as a station to
connect to a Root AP. You should assign the SSID of the Root AP
here or click 'Select Site Survey' button to choose a Root AP.
Click 'Site Survey' button, then a "Wireless Site Survey Table" will
pop up. It will list all available access points nearby. You can select
one access point in the table and the access point will join wireless
LAN through this access point.