No. It is not. Not if you are using a Fedora version later than Fedora Core 6. That is the last Fedora version to use bcm43xx. All of the following driver methods are known to work with the BCM4306 chipset in any version of Fedora after Fedora Core 6. Choose one and do it...
The native b43 driver
The b43 driver is a kind of reverse engineered driver for Linux but still requires firmware that has to be extracted from a Broadcom driver. It has been included as a module with Fedora kernels since Fedora 7 when it replaced its predecessor, the bcm43xx driver. The Linux Wireless site
(the home of b43 nowadays) lists the BCM4306 amongst the supported chipsets. And I use it with three wireless cards with the BCM4306 chipset. The steps to install the firmware for it are...
tar xjf broadcom-wl-18.104.22.168.tar.bz2
b43-fwcutter -w /lib/firmware wl_apsta_mimo.o
Now reboot and establish the connection using the NetworkManager tray icon (left-click it). If your router is broadcasting its SSID, then you should see your network (router SSID) in the list of available networks. Click it and give NetworkManager the information that it requests. If your router is not broadcasting its SSID, then you will not see your network listed. I recommend turning SSID broadcast on. If you insist that it be turned off, then left-click on the NetworkManager tray icon and choose "Connect to hidden wireless network" or "Connect to other wireless network". It not necessary to do anything in the old Network Configuration utility. I don't even have a wireless connection in the Network Configuration utility, and yet I am connected with b43 and NetworkManager now.
Dangermouse's autoten script
It's well-known around here. It installs a bunch of common things one of which is the firmware for the native b43 driver. Get it and the instructions here...
Autoten rpm for easy installation
Dangermouse also offers an RPM package that installs the firmware for the native b43 driver. It basically does what the autoten script does, but the autoten script does a bunch of other things, too. Here is where to get that RPM and the instructions...
Broadcom driver installation
There is also the option of using ndiswrapper to allow the card's Windows driver to work in Fedora. This driver method will work in any version of Fedora ever released. I used it for a long time with my three BCM4306 cards. But I prefer b43 and recommend that you try those two methods above before trying ndiswrapper. Details of this option are available if they become necessary. I doubt it will come to that with your card.