WAN interface wireless client persistent uplink connection

[Koguni]

Have set up wireless client to internet uplink (AP)  on WAN interface as BSS infrastructure type interface, but it disconnects several minutes after connect and  don't retry again ever.

One method to bring it back up (for several minutes) is to reboot device or touch some settings (make this one time, didn't find what I've done again) at web interface.

How to make it persistent, or how to bring wireless link back up manually from vga console or ssh command line or web interface?