I have a WMP54G that also has the BCM4306 chipset, and it has worked well for years with the b43 driver module that is included with the Linux kernel. But it needs firmware that I have to install. Here is what I would do...
Confirm that the b43 module is being loaded by the kernel...
If b43 is in the list generated by that, then open a terminal and install the firmware for it by running these commands while using a wired connection to the Internet (you can paste them from here directly into a terminal)...
tar xjf broadcom-wl-18.104.22.168.tar.bz2
b43-fwcutter -w /lib/firmware wl_apsta_mimo.o
Those commands merely download a Broadcom driver source file, extract the firmware from it, and copy about thirty .fw files to a folder named /lib/firmware/b43. And that's all that they do. Anyway, after those complete successfully, reboot or restart NetworkManager and check for available networks.
If you don't have a wired connection to do the wget step, then download that tarball using another computer. Somehow transfer it to the wireless computer and continue on with the other steps.
Another acceptable option is to install the package b43-openfwwf (yum install b43-openfwwf
) which installs open source firmware that also should work with a BCM4306 chipset. If that yum command fails (since Fedora 14 has been archived), or if you have no Internet connection, then download the rpm file from the archives
and manually install it with yum or rpm. Reboot or restart NetworkManager and check for available networks.