I'll wait for more but I'd be guessing you want to supply the internet to other devices. Google this and it might help.
I have been using a Linksys wireless-n wrt160n with my envoy to have enternet connection but no longer have cable internet. The envoy connects by rj45. I now have at&t air card for my internet connection. I am using Windows7 on my PC. I ned to know what hardware I need to connect the envoy to connect wireless to At&t air card. Thank You