I have Ubuntu 12.10 64 bits kernel 3.5.0-22 running on a Dell Precision M6700. The wireless controller is a Broadcom BCM43228 (802.11abgn, the router also is 802.11abgn); it didn't install on a fresh install, so I added the bcmwl-kernel-source package and I got the wireless network working... sort of. This is a dual boot machine, and under the same conditions that the connection running Windows is stable, running Linux it is anything but; every now and then it disconnects itself, it doesn't manage to connect on its own to the router, requiring a repeater (which is not necessary with Windows) and even then there are times when it connects to the network without really working (e.g. pinging the router itself returns "unreachable"). Frequently when reconnecting it asks the network password again. At times it doesn't manage to connect at all, even with the repeater turned on. Things only really work if I am practically stuck to the router, but that sort of defeats the whole idea of wireless connections.
Any suggestions are greatly appreciated. Ken