Wireless connected but asks for connection authentication every couple of minutes and won't let me get on Firefox

I finally got my computer to recognize my wireless card and I see a signal from the icon for wireless at the top right of the screen, but it will not let me get on the internet and asks for authentication by wireless network every couple of minutes. The driver is loaded (assuming it is the proper one) for a Broadcom BCM 4318 (using update via ethernet cable). Any suggestions? I have confirmed my passcode for my router.