You have two options... one is to run the script:

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#!/bin/sh
rmmod wl12xx
modprobe wl12xx
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which you can put into a text file and use "chmod +x" to make the file executable.

The easier way is to use "Wifi Switcher", first disable and then enable the wifi. I use this way every time I run kismet or aircrack-ng.

thanks for that